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String Theory - Science topic

Discussion of problems of string theories.
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Hello Research Gate team!
Looking at the Weekly Report for 2-9 August I’ve got a Question for you.
The results that were DISPLAYED by Research Gate DURING that week (I check/record them DAILY) were:
Motley String Book: +1/28 reads
Triangulation of Elliptic Curve: +1/66 reads
Breakthrough to Higher Dimensions with Motley String, Anyone (for Stanford team): +3/21 reads
Motley String theory Project Update (new “Motley String and Quantum Mechanics” paper, posted on Friday 7 August): +5/49 reads
Which means that Total for that week SHOULD have been: 5+3+1+1=+10/760 (from 750 previous week)
But Weekly Report I received from Research Gate said that it was: +6/756.
That is -4 (MINUS FORTY Percent) with respect to DISPLAYED reads DURING the week!
Therefore, I wonder WHICH type of Mathematics have you used to arrive at YOUR Total?
P-adic, Quantum or something else? Possibly Minsk or Kremlin type of “calculus”??
Can you EXPLAIN please?
Best regards,
George Matveev
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Last week (August 14-21, 2022) my Research Index was 27.2.
But today (23 August 2022) RG says that my Research Index became 26.2 WOW!
Any Explanation for this my statistics going DOWN???
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1) Can the existence of an aether be compatible with local Lorentz invariance?
2) Can classical rigid bodies in translation be studied in this framework?
By changing the synchronization condition of the clocks of inertial frames, the answer to 1) and 2) seems to be affirmative. This synchronization clearly violates global Lorentz symmetry but it preserves Lorenzt symmetry in the vecinity of each point of flat spacetime.
Christian Corda showed in 2019 that this effect of clock synchronization is a necessary condition to explain the Mössbauer rotor experiment (Honorable Mention at the Gravity Research Foundation 2018). In fact, it can be easily shown that it is a necessary condition to apply the Lorentz transformation to any experiment involving high velocity particles traveling along two distant points (including the linear Sagnac effect) .
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We may consider the time of a clock placed at an arbitrary coordinate x to be t and the time of a clock placed at an arbitrary coordinate xP to be tP. Let the offset (t – tP) between the two clocks be:
1) (t – tP) = v (x - xP)/c2
where (t-tP) is the so-called Sagnac correction. If we call g to the Lorentz factor for v and we insert 1) into the time-like component of the Lorentz transformation T = g (t - vx/c2) we get:
2) T = g (tP - vxP/c2)
On the other hand, if we assume that the origins coincide x = X = 0 at time tP = 0 we may write down the space-like component of the Lorentz transformation as:
3) X = g(x - vtP)
Assuming that both clocks are placed at the same point x = xP , inserting x =xP , X = XP , T = TP into 2)3) yields:
4) XP = g (xP - vtP)
5) TP = g (tP - vxP/c2)
which is the local Lorentz transformation for an event happening at point P. On the other hand , if the distance between x and xP is different from 0 and xP is placed at the origin of coordinates, we may insert xP = 0 into 2)3) to get:
6) X = g (x - vtP)
7) T = g tP
which is a change of coordinates that it:
- Is compatible with GPS simultaneity.
- Is compatible with the Sagnac effect. This effect can be explained in a very straightfordward manner without the need of using GR or the Langevin coordinates.
- Is compatible with the existence of relativistic extended rigid bodies in translation using the classical definition of rigidity instead of the Born´s definition.
- Can be applied to solve the 2 problems of the preprint below.
- Is compatible with all experimenat corroborations of SR: aberration of light, Ives -Stilwell experiment, Hafele-Keating experiment, ...
Thus, we may conclude that, considering the synchronization condition 1):
a) We get Lorentz invariance at each point of flat space-time (eqs. 4-5) when we use a unique single clock.
b) The Lorentz invariance is broken out when we use two clocks to measure time intervals for long displacements (eqs. 6-7).
c) We need to consider the frame with respect to which we must define the velocity v of the synchronization condition (eq 1). This frame has v = 0 and it plays the role of an absolute preferred frame.
a)b)c) suggest that the Thomas precession is a local effect that cannot manifest for long displacements.
More information in:
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There is a difference between Lorentz transformations and scale transformations.
Special relativity satisfies Lorentzian symmetry due to the constancy of the speed of light and the special relativity principle.
However, in reality, the aether makes the speed of light locally invariant, so the Lorentz transformation is not necessary.
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My understanding is the universe is usually considered to be n-dimensional, and thus metrizable. But is this a necessary consequence of physical theory, such as string theory?
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That n from n-dimensional merely shows how many properties one needs to locate things.
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If something is next to something without extension that itself has no extension, it never manages to actually be SPACE.  Instead it is the juxtaposition of non extended singularities, manufactured into a matrix in whose connection singularities are impossible.  It makes no sense to me how space can be the juxtaposition of non extended and non extendable single locales who generate a system of ways of articulating spacial relations of all objects made up of material. 
How can material be made of nothing more than frequency of strings working harmoniously.  It makes no sense quantum Mechanics...it must be wrong as a model goes, even though it's models are enormously precise in some of their predictions. 
IF I am wrong and it is correct can anyone please explain to me how something non extended can be next to something else non extended to between the two of them form a displacement? It's impossible right?  So please explaing Quantum Mechanics to me then.
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They cannot have extensions .They act in such a manner as to mathematically represent extensions .
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Subatomic particles create the situation above matter in the universe, and so the quality of the object on matter is formed by differentiating from subatomic, so why is that so? Sub-item and sub-item reasons do not work in the same way. Let's think that matter consists of six protons, electrons and neutrons, there are quarks, etc. They also consist of these 3 values. Let's see. If proton positive. If the electron is negative neutron has no charge, there is a mirror substance under the atom, just like the mirror neuron in our brain. Because being a neutron means no load, that is symmetrical. It means equal positive and negative charge. So what does this mean? We first put forward this based on the mirror neuron. First of all, let's look at the property of the mirror neuron: they provide the quality of imitating each other. Mirror matter is also subatomic. Thus, when the proton and electron imitate each other subatomic, a movement takes place in two places at the same time. So how do we reconcile it with string theory? String theory of the subatomic. He says that protons and electrons are composed of one-dimensional filamentous structures. What happens if one filamentous structure imitates the other filamentary structure? At the same time, in more than one place, the same function and action becomes a filamentous substance. Here, the mirror matter feature occurs when the protons and electrons in the string theory, that is, the structures that the subatomic contains, act in the same way. From here, the proton and electron, which are in two places at the same time, multiply the information. And this knowledge is the knowledge of matter. For the supermaterial state, protons and electrons, which can be in two different places at the same time according to quantum and string theory, depending on the same mutual movement of gold, that is, proton and electron. When the electron acts like a proton, it goes beyond matter. When protons act like electrons, they form matter gold. thanks
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Hakan Unal You might be interested in the nature of matter and electric charge explained in this presentation:
Richard
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You can find the wording in the attached file PR1-v3.pdf. Any comment will be wellcome.
More on this topic at:
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I think that an interesting point is that, using units with c = 1, the 4-velocity (dt,dx,0,0) is a 1-tensor that is the same for any offset of clocks of the inertial frame. Then we have that the 4-velocity (dt,dx,0,0) transforms the same for any synchronization, it satisfies the Einstein addition of velocities and consequently it also satisfies the principle of constancy of speed of light. On the other hand, as it behaves like a tensor under Lorentz transformations, the relativity principle holds for it an for all derived 1-tensors like velocity, acceleration and so on.
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A fascinating question in theoretical physics is whether it is possible to extend Einstein's ideas beyond gravitation to all aspects of physics. The energy-momentum tensor is usually defined extrinsically over the space-time manifold. But could it rather be derived from the geometry alone ? Likewise our local subjective notion of time is given by a local orientation which need not be globally consistent as in Gödel's famous model.
It has been proposed that space-time may have a foam- or sponge-like fine-grained structure (possible involving extra dimensions) which explains energy and matter and the other fundamental forces in a Kaluza-Klein style. That is, "microlocally" the topology of the space-time manifold is highly complex and there may be even a direct relationship between mass, energy and cohomology complexes in an appropriate derived category. At this fine scale there may even be non-local wormholes that connect distant regions of space-time and explain quantum entanglement.
But why not consider the universe as a Thom-Mather stratified space (one can think of this as a smooth version of analytic spaces or algebraic varieties) rather than a manifold ? In this case "singularities" would be "natural" structures not pathologies as in black holes. It is difficult not to think of matter (or localised energy) as corresponding to a singular region of this stratified space. Has this approach been considered in the literature ?
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Clarence Lewis Protin I had a look on Wikipedia to find out about Thom-Mather stratified spaces:
It mentions its use in the study of singularities. My comment about trying to apply this approach to cosmology is based on the Spacetime Wave theory:
From this worldview, singularities do not exist in physics and the laws of physics apply everywhere and for all time. Also the idea that spacetime may have a sponge like or fine grained structure (quantum fluctuations in empty space) is ruled out by the adoption of the Einstein equations of GR as the fundamental equations of spacetime at all scales. This means that if the Mass Energy tensor is identically zero then spacetime curvature must be identically zero.
This the idea of quantum fluctuations in empty space from quantum theory has to give way.
Richard
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at large scale, do earth goes around sun or particles of the earth goes around the particles of the sun?
i am proposing new theory which says; the Gravitational force in between two objects depends on the most probable distance in between them.....
my dear unique scholars welcome to your valuable feedback, answers, comments....
thank you
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In chord space, chord interaction is manifested as spatial interaction, the basic way is: separation and combination.
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Chord language is a natural information system, The basic forms are: chords (quantized discrete spectrum), chord geometry (open, closed, membrane strings), and mathematical models of chords (temperament, harmonics), often used in time (music) ), space (painting), life (meridians) and other chord semantic expressions; chord semantics comes from the chord spectrum, which is the manifestation of natural spirit and natural laws.
The impression of chord observation is: the language of chords is the language of time-space (life); the language of all things.
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Music and physics are connected by sound waves and accoustics. Music could not exist without it's physical aspect.
Diana Ambache
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Question solved. We overviewed possible theories of mass defect in gravitation. Energy is conserved in SR and QM (see NOTES), but matter is not conserved in SR or in QM. This is not dependent on any of Noether's theorems. Our previous work may be helpful here:
NOTES:
I am not trying to convince anyone that Minkowski SR is right, and that is the only SR we use in physics That was the thing to do, though ineffective, 100+ years ago. Today, we just watch with mild disbelief, and some amusement.
There are other differences in the SR treatment. For example, matterless energy exists, such as a photon. But, there is no "energyless" matter. Motion is always relative in SR, as well. This is a simple impediment for matter to change with motion, or speed, or acceleration. A fast neutrino passing nearby cannot change one's amount of matter. Motion cannot change mass, even if very fast.
Why, then, two masses reduce their mass when put closer together? Newton gravity theory does not explain. Einstein gravity theory neither. What is your qualified opinion?
NOTES:
  1. Minkowski special relativity (SR) and Bohr quantum mechanics (QM) apply certainly.
  2. QM and SR are no longer subject to physics discussions at this level, and not in CS, maybe in History. Maxwell equations are incorrect, and do not explain (e.g.) diamagnetism or lasers. We do not accept the Copenhagen interpretation, nor any "measurement effect" or "wave collapse".
  3. The laser was invented already circa 1958, uses QM and SR, contradicts the Maxwell equations, and these topics disqualify who question them. More than 55,000 patents involving the laser have been granted in the United States.
  4. We declare that resolved issues are off-topic, such as "relativistic mass" (not in nature), Maxwell equations (incorrect), QM (cannot be denied), and SR (cannot be denied).
  5. We will not respond to off-topic comments, valuing the discussion quality not the points.
  6. Off-topic comments are directed to the history of Physics or Mathematics.
  7. These and other examples of unacceptable behavior by participants here and prohibited by the RG ToS, even when presented as "ironic" or "joking," include ad hominem attacks and lack of civility. Lack of immediate enforcement by RG is not acceptance.
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Yes, we no longer see particles in the entire universe, present and past for 13.8 billion years. Therefore, we also should not consider mass -- but we can can consider matter and energy. What replaces then, the most famous. equation in Physics, E = mc^2?
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I think the chaos applies to all theory because chaos existed in classical physics itself so the chaos should exists in quantum and relativity
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No-because chaos is known as a property of classical systems; so it doesn't have anything to do with providing an obstacle for quantizing gravity, i.e. finding the quantum theory, whose classical limit is general relativity. The obstacle to that, rather, is finding the-qantum-degrees of freedom that can resolve the singularities, that appear in gravitational collapse.
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What is the physical significance of the study of compact object in higher dimensions i.e., beyond 3+1 dimensions? We know that 10D exists in case of string theory but the idea of string theory is in theoretical stage, the observational evidence can't be found till now , on the other hand the compact star is an observable object.
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André Michaud : I DO think that progress may eventually be made. I simply see that all of the arguments made in favor of extra dimensions in this and every other discussion I've read in the last 50 years include not only great enthusiasm about the concept of extra dimensions, but also note that to date, not one theory has succeeded in convincing the general community that it is valid. Here and there, the comments above state that there are advantages to thinking of extra dimensions in one way or another, but they always include the caveat that the theory involved has yet to be proven or has been abandoned (unsaid is the reason that it proved incapable of producing any testable predictions). So I believe that we need a "quantum leap" in our mathematical and physical understanding of things before any useful theory using extra dimensions has any hope of becoming generally accepted. And although strictly speaking a quantum anything refers to the smallest step imaginable, in its usage as a phrase, 50+ years of reading about so-far useless theories convince me that although at some distant date someone may develop an extra-dimensional theory that is not only mathematically "useful" but also produces testable predictions, none of us will still be alive to read about it. I don't consider that view pessimistic, but pragmatic. Why waste my time reading about probable nonsense, when there are so many things to read about that produce useful results? So along that line, though everyone is free to criticize that viewpoint, I will not be reading any more of the comments about this thread. Instead, I'll be working on projects that are producing useful results, at least in the opinion of my colleagues and students. However, I do keep up with news about cosmology and associated fields, such as the numerous efforts to use extra-dimensional mathematics to solve cosmological problems, and in the unlikely event that I live long enough to read about an extra-dimensional theory that does produce testable and provable results, I will be perfectly happy to accept it as a realistic possibility.
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Specifically I am interested in knowing if anyone has had students compare  the concepts of parallel universes (multiverse) proposed by both theories?
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Nice Dear Elizabeth Marie Watts
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Hello Everyone,
as you probably know All existing String theories are formulated in High-Dimensional space time.
Motley String theory has successfully established connection between High-Dimensional String theories (All models) and Observable 4-dimensional world and as result solved ALL SIX major problems the Standard Model could not solve.
Quite recently Motley String theory has also explained Gravity’s extreme weakness and absence of Supersymmetric particles (so called SPARTICLES) via High-Dimensionality, see file Matveev-MotleyStringSUSYUniverse.pdf attached.
The question of Experimental Verification of Motley String theory is therefore theoretically addressed (until the Proposed Experiment is carried out) via Indirect method of measuring slopes of W, Z BOSONS Scattering, similar to the Regge slopes of HADRONIC resonances, see WZScatterExperiment.pdf file for details of the Proposed Experiment.
The BIG Question that REMAINS to be answered is this: HOW we can make DIRECT measurements of High-Dimensional Physics phenomena using some New types of Detectors and Sensors?
Is it possible at all?
Which Physical Principles and Engineering Solutions can be used to make such measurements today?
The Other side of this Question has possibly something to do with our MIND and HUMAN BRAIN activity as described in both Scientific and General Literature.
TWO major examples of this PSYCHOLOGICAL Approach are mentioned in the first paper attached: W.Pauli and C.G.Jung collaboration and Brian Josephson’s Mind-Matter Interaction project at Cavendish Laboratory of Cambridge University.
Any Ideas are Very Welcome, from Physicists as well as Engineers!!
Possibly even Psychologists and Biologists could contribute their two cents to this?
Best regards,
George Matveev
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I suggest
visit this websitess://www.researchgate.net/project/Motley-String-Theory
More than detector about this work .
I think G.M detector as best of all
Kind regard
Qusay Kh. Al_Dulamey
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Hello LHCb team.
This is W Z Bosons Scattering Experiment Proposal.
Experiment goal: carry out Experiment similar to MESONS (quark-antiquark) scattering experiments where Regge slopes were measured and check if experiments with BOSONS produce different slopes.
See details in GM-WZScatterExperiment and GM-MotleyStringSUSYUniverse PDF files attached.
Motivation: according to the Motley String theory, String Tensions T(i) are Different in i-th spacial dimensions.
Therefore, by scattering W and Z BOSONS we may see Different slope values compared with Regge slopes known from HADRONS scattering experiments.
If that is indeed the case, as Motley String theory suggests, it would mean that Bosons leave in a HIGHER Dimensional Space-time from Fermions (e.g. mesons). Heterotic String model also implies this.
Benefits: This experiment could help us identify SINGLE String theory as Valid Candidate for Theory of Everything (ToE) and give us Much Better Understanding of Physics Beyond the Standard Model and even beyond our current understanding of String Theory!
This Experiment Proposal was initially submitted in late July 2019 as part of my application for job at CERN.
Best regards,
George Yury Matveev
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Hi
Javad Fardaei
, nice to see your Interest in the High-Dimensional Physics/Universe!
My paper suggests and implies that we must FIRST CONFIRM that we indeed live in a Higher-Dimensional Universe. As a FIRST STEP.
AFTER that we will be BETTER prepared to IDENTIFY and ANALYSE the possible DOMAINS with (POSSIBLY) Different Spacial dimensions (both Motley String theory and Heterotic String Model suggest that) and BEGIN STUDY of them in earnest, using some NEW Methods that still REMAIN to be IDENTIFIED!
In my "W, Z bosons Scatter Experiment" proposal for CERN I suggested and described ONE such method.
David Deutsch has described ANOTHER method of CONFIRMING High-Dimensionality of the Universe using INTERFEROMETER and MIRRORS in his well known book.
Most likely there are some OTHER Methods and Techniques of making measurements of High-Dimensional Physics??? That is still OPEN Question.
Possibly Quantum Mechanics Experts (like yourself) can come up with one or two new PRACTICAL Ideas? ;-)
Best regards,
George Matveev
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Hello Everyone,
as you probably know All existing String theories are formulated in High-Dimensional space time.
Motley String theory has successfully established connection between High-Dimensional String theories (All models) and Observable 4-dimensional world and as result solved ALL SIX major problems the Standard Model could not solve.
Quite recently Motley String theory has also explained Gravity’s extreme weakness and absence of Supersymmetric particles (so called SPARTICLES) via High-Dimensionality, see file Matveev-MotleyStringSUSYUniverse.pdf attached.
The question of Experimental Verification of Motley String theory is therefore theoretically addressed (until the Proposed Experiment is carried out) via Indirect method of measuring slopes of W, Z BOSONS Scattering, similar to the Regge slopes of HADRONIC resonances, see WZScatterExperiment.pdf file for details of the Proposed Experiment.
The BIG Question that REMAINS to be answered is this: HOW we can make DIRECT measurements of High-Dimensional Physics phenomena using some New types of Detectors and Sensors?
Is it possible at all?
Which Physical Principles and Engineering Solutions can be used to make such measurements today?
The Other side of this Question has possibly something to do with our MIND and HUMAN BRAIN activity as described in both Scientific and General Literature.
TWO major examples of this PSYCHOLOGICAL Approach are mentioned in the first paper attached: W.Pauli and C.G.Jung collaboration and Brian Josephson’s Mind-Matter Interaction project at Cavendish Laboratory of Cambridge University.
Any Ideas are Very Welcome, from Physicists as well as Engineers!!
Possibly even Psychologists and Biologists could contribute their "two cents" to this?
Best regards,
George Matveev
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Hej,
appreciate your LONG reply message.
It is mentioned in my question, there SEEMS to be INDIRECT and QUITE SIMPLE way for us to CONFIRM that we indeed live in HIGH-Dimensional Universe!
It is similar to Regge slopes of Hadronic Resonances.
You can find description of "W, Z Bosons Scatter Experiment Proposal" for CERN attached to the Question or on my Motley String Project.
I first sent the Proposal to CERN Theory Division and TOP Management people in August 2019.
Not sure what THEY think since there was NO REPLY so far...
Managers are VERY BUSY and IMPORTANT people, do not like to be disturbed by researchers... :-)
If you have ANY comments regarding the Proposed Experiment, you are Most Welcome to provide them!
Until some one carries out the Proposed Experiment, String theory Researchers will have NO Choice but to Develop Theories that FIT their Models...and Provide ANSWERS to existing problems.
Motley String theory SOLVES ALL EXISTING Problems of High Energy Physics!
Cheers,
George Matveev
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Hello Stanford team!
Anyone is ready/looking for Extra Spacial Dimensions?
Motley String Theory is based on two simple Postulates:
Postulate 1: Every spacial dimension of String has a unique intrinsic property which we call "color".
Postulate 2: There is force between spacial dimensions of string such that it makes dimensions of complementary colors (Red_i , Green_i, Blue_i) interact and unite in a colorless threads perceived as observable dimensions.
As a result, Motley String theory solves ALL SIX Major Problems the Standard Model
could not explain:
1. Number of elementary particles (6 quarks + 6 leptons)
2. Quarks Fractional Charges
3. Quarks Confinement
4. Quarks Oscillations
5. Neutrinos Oscillations
6. Dark Energy/Mass problem
One web page overview of the Motley String theory is on my web site:
Moreover, in August 2019 I created a W Z bosons Scatter Experiment Proposal (see attached document Matveev-WZScatterExperiment.pdf with details) for CERN SPS or LHC.
The Proposed Experiment is somewhat similar to the one conducted by SPS team in 1983,
but one needs to use BOSONS instead of Hadrons.
The Expected RESULT and GOAL of the Experiment is to identifying the UNIQUE String Theory (Motley Heterotic String) as our Leading Candidate for ToE (Theory of Everything).
Major reason for such Experiment Result is the FACT that Motley String Model is EQUALLY APPLICABLE to BOTH Superstring model and Bosonic string model and thus to Heterotic String model for reasons explained in the attached document.
As far as I can see there is NOTHING that prevents Stanford Accelerator team from conducting the proposed Experiment and Discovering TRUE Dimensionalit{y,ies} of the Universe we live in.
Also Motley String offers Plausible Explanation for “Dark Energy/Mass” problem of modern Astrophysics.
My first book “Motley String or What Everything is made of” was first published by German Scholars Press in June 2018.
Third extended Edition (with New Chapter on Elliptic Curve – Hydrogen Atom Link) was published in April 2019.
The book is available on Publishers web shop:
as well as on about a dozen of other web shops: Adlibris, Amazon, etc.
Your Constructive EXPERIMENTALIST Feedback would be Much Appreciated!
Best regards,
George Yury Matveev
P.S. other Particle Accelerators with comparable to SPS/LHC characteristics could possibly try to carry out the Proposed Experiment as well.
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"Spatial" , or "spacelike", not 'spacial'. Just sayin'.
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What is the difference between loop quantum gravity and string theory?
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In loop quantum gravity, space-time is a network, and nodes replace the smooth background of Einstein’s theory of gravity. Loop quantum gravity studies bits; on the other hand, string theory studies the behavior of objects within space-time.
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I would like to ask what is the structure of space-time in string theory. Is it discrete as it is in loop quantum gravity or causal dynamical triangulations? Or is it described by a manifold as it is the case in general theory of relativity?
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Rica ederim, dear Furkan Semih Dündar. Glad to help.
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In the context of string theory, it has been concluded that space is not fundamental but a phenomena emerging from quantum entanglement. To start a debate on what the core principle behind such mathematical conclusion could be, I suggest that the reason why space cannot be fundamental is because it contradicts the fact that energy is impermanent or otherwise said: continuously changing (and therefore continuously arising).
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Space and other conceptual notions have been historically used to describe what we perceive in mathematical form. They can be understood in the context of conventional agreements, necessary to formulate theories and gain insights into natural phenomena.
In turn, conclusions gained from such theories as well as experimental findings have helped question our sensorial perception.
For example, we might tend to perceive physical objects as individual and even unchanging units yet we know no surface can be actually found that marks the end/beginning of any object.
Space is in the view here presented of a similar quality: is conventionally agreed upon and ingrained in our human experience when sensorial perception is taken as absolute truth.
If we want to understand energy beyond our limited perception, space needs to be examined/questioned.
Relenting to endeavour in such investigation is (in our view) the cause why general relativity and quantum physics cannot be merged and why concepts such as entanglement can remain mysterious or contradictory with grosser / classical aspects of energy.
So space can describe reality to certain level of practicality as you mentioned, yet it cannot describe reality ultimately.
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There is a plenty of examples of classical solutions to low-energy effective theories that were proved to have vanishing α'-corrections to all orders and hence be also perturbatively exact string solutions in the literature, see e.g.
Since in all the literature I'm familiar with, the proof of α'-exactness of leading-order solutions relied heavily on the fact that the corresponding spacetime metric admits a covariantly constant null Killing vector, I'm currious if this is always the case.
Is anyone aware of some paper which proves α'-exactness for leading-order solutions beyond those with spacetime backgrounds admitting a covariantly constant null Killing vector?
(I'm aware of the fact there are also different approaches in finding exact string solutions that do not relly on proving α'-exactness of leading-order solutions and hence may yield exact string backgrounds with no covariantly constant null Killing vectors but the present question is focused strictly on this approach.)
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Stam Nicolis So, your problem with my question lies in the terminology I used - correct? Specifically, is it the term "string solutions", by which I mean solutions of effective field equations for the background fields?
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What are Ramanujan's modular functions, what are they for and how do they apply in relativity, quantum physics and string theory? And where can I consult bibliography about it?
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Dear Carlos,
I think a good introduction to Ramanujan modular forms (an advanced subject) is:
S. Kanemitsu et al.: Ramanujan's Formula and Modular Forms, Number Theoretic Method-Future Trends; Kluwer (2003). See pages 159-212.
Fabio M. S. Lima
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Opinion on how we and our school is doing in terms of identifying string theory in our ordinary business of life. The synthesis of new Physics and New Economics which happens as the resultant of complex forces and particles accelerated by light environment in the solar system and the learning field.
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> Opinion on how we and our school is doing in terms of identifying string theory in our ordinary business of life.
Directly I cannot see any way to link string theory with our everyday lives. String theory deals with a proposal of a unification scheme. It potentially gives a framework in which to discuss physics well outside of our usual experiences and the energy scales of collider experiments.
In directly, mathematical methods and ideas that originate in string theory (and related things) could find applications in other areas such as engineering, economic theory etc. However, right now I cannot think of a great example. Maybe one day.
And then there is the philosophical benefit of questioning the nature of our reality. This desire to know more is part of who we are.
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Greetings,
Completing Bachelors in Engineering this June'19, I thought I'd start with Masters/PhD in Gravitational Physics this fall but I received rejections from almost every graduate school I applied to. To where I received an offer from, I won't be able to pay off the tuition fees.
Of course I knew that to receive an offer, one needs to have some experience with the subject. With the engineering curriculum on one hand, I tried to manage my interests in gravity. From watching lecture videos by Frederic Schuller and Leonard Susskind to reading books by Sean Carrol and to even doing a summer research internship on black hole geometries, I tried to gain experience on the subject.
I wish to understand relativity from a mathematical point of view.
" A good course in more abstract algebra dealing with vector spaces, inner products/orthogonality, and that sort of thing is a must. To my knowledge this is normally taught in a second year linear algebra course and is typically kept out of first year courses. Obviously a course in differential equations is required and probably a course in partial differential equations is required as well.
The question is more about the mathematical aspect, I'd say having a course in analysis up to topological spaces is a huge plus. That way if you're curious about the more mathematical nature of manifolds, you could pick up a book like Lee and be off to the races. If you want to study anything at a level higher, say Wald, then a course in analysis including topological spaces is a must.
I'd also say a good course in classical differential geometry (2 and 3 dimensional things) is a good pre-req to build a geometrical idea of what is going on, albeit the methods used in those types of courses do not generalise. "
- Professor X
^I am looking for an opportunity to study all of this.
I would be grateful for any opportunity/guidance given.
Thanking you
PS: I really wanted to do Part III of the Mathematical Tripos from Cambridge University, but sadly my grades won't allow me to even apply :p
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There are two sides to your problem: the practical and the ambitional. You will have to look after both. Recognize the practical issues but don't let go of your ambition. You may have to get a temporary job just to live, but that does not mean you give up on your dreams.
Your problem is not unique and has been overcome by famous scientists. Faraday started working for a bookbinder and ended as a revered scientist. His personal drive got him through. Dirac got a first degree in electrical engineering and ended as a revered theorist. Einstein worked early on in a Patent office and ended as a revered theorist. Other examples can be found, such as Ramanujan. Now there's a great example of talent beating disadvantage. So you see, it's not the end of the world if there are practical difficulties in your way at this time in your life. If you keep your spirits high, focused on what really interests you, you may succeed. It may be very hard, but don't give up.
You should understand that training is not enough. You have to practice being creative. Some people on this forum will probably disagree with the following suggestion, but have a go at writing a paper on a novel topic and seeing the reaction. It may take time to find a problem that you can work on, and you may very well get rejection. But having a go will teach you more than doing a lecture course on analysis. Papers do not all have to be in quantum field theory or relativity. Go on the arXives and see what sort of topics are viable for you. Most likely, at this stage, it might be in the General Physics section. But at least you might start from there.
Good luck in your ambition. Never give up.
George Jaroszkiewicz
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The classical limit of loop quantum gravity is Einstein-Cartan theory (EC), not general relativity (GR). I would like to know whether the other main approach to quantum gravity - string theory - also has as its classical limit EC, with torsion and the spin-torsion field equation. Or is its classical limit GR or something else?
At the April APS meeting:
(a) I attended a presentation on a loop quantum gravity model of the origin of cosmic inflation. I asked the researcher what quantization contributes to the model, compared to just using classical EC (which causes inflation-like expansion). The presenter thought the classical limit of loop quantum gravity is GR.
(b) A researcher at a major university told me that the Hamiltonian and other mathematical properties of EC as so much superior to those of GR that they do all their theoretical research based on EC and not GR.
Is EC quietly displacing GR as the foundation of quantum gravity research, and do some of the researchers not recognize this is happening?
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Dear Stam,
The continuum limit may be unnecessary for someone like you who sees EC as a modest extension to GR that enables modeling exchange of intrinsi and orbital angumar momentum (and improse some other things like elminating some singularities from GR).
However, I believe 99% of the graviational researchers (maybe 99% of researchers ove age 40) dont' accept this point of view. For them, the derivation of translatonal holonomy from a single Kerr mass and the continuum limit of distributions of Kerr masses might, just might, ignite a flame insight, or at least respect.
As an example of the problem, in January 2019, I submitted a slightly edited version of " to Phys Rev D, after trying CQG And GRG journals in the past year or two. I have appended the vebatim referre report below, and my response. Every sentence of the review after the first one is unmitigated horsefeathers.I have been on this case for 30 years, and I know what passes for competence out there.
The editor's response was brief: he stands by the original review.
Planck wrote: “A new scientific truth [that alters the elements of a field] does not triumph by persuading its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
--Max Planck, “Scientific Autobiography and Other Papers,” 1949, p 33-34.Quoted in “The Structure of Scientific Revolutions,” by Thomas Kuhn, 4th edition, 2012, p 150.
I would prefer that someone who sees the light like you would help to get this into the mainstream.
Referee report from Physical Review D (verbatim)
The aim of the manuscript is to derive Einstein-Cartan theory form General Relativity by showing that in some GR configurations involving a distribution of Kerr black holes, there exists torsion using the concept of "translational holonomy." It is not at all clear what "translational holonomy" is supposed to be. The usual holonomy that defines curvature (what the author calls rotational holonomy) has the structure that it does precisely because torsion cancels. Therefore, I do not see how one can "derive" torsion when none existed in the first place. Moreover, the configuration that the author uses to "prove" this is not a stationary configuration as the Kerr masses will feel an attractive force with respect to one another.
My rebuttal
The first sentence of the review correctly states the most important claim of the work.
1) “It is not at all clear what ‘translational holonomy’ is supposed to be.”
The concept of holonomy is defined in references [1] page 87 and [2] page 71.
Translations are not treated the same as rotations in spacetime gauge theory. The root issue is that the geometric structure group (symmetry group) of GR and EC is the semidirect product of the Lorentz group and translations (which has a fixed origin point), not the Poincaré group (which has no preferred origin point). See [3] page 128 for a rather abstract statement of this positon. Therefore we must modify the definition of holonomy for translations.
The definition and construction of translational holonomy is discussed in the manuscript in sections 3.1 and 3.2.
I have provided a brief intuitive description of translational holonomy in section 3 of this document.
2) “The usual holonomy that defines curvature has the structure that it does precisely because torsion cancels.”
This statement is false in Riemannian geometry and in RC. It is a denial that RC can exist.
I believe the referee has in mind the derivation of Riemannian curvature by constructing a piecewise almost–closed loop from four geodesic segments. In this construction, the “failure-to-close” vector is generally nonzero for finite loops. The quantity that vanishes is:
limit[t → 0] (failure-to-close vector)/t^2 = 0.
The manuscript uses only closed loops, in which the “failure-to-close” vector is by definition zero. It use no geodesics.
In RC, my derivations of rotational curvature from rotational holonomy and of translational curvature (affine torsion) from translational holonomy work fine. See manuscript section 3.2. “Definition of curvature in terms of holonomy.”
(manuscript equation 3) limit[t → 0] (rotational holonomy)/t2 = rotational curvature
(manuscript equation 4) limit[t → 0] (translational holonomy)/t2 = translational curvature = torsion
3) “I do not see how one can ‘derive’ torsion when none existed in the first place.”
The disruption of ordinary geometry (singularity?) inside each Kerr mass makes this possible, just as the core of a dislocation in a crystal enables torsion to exist around a dislocation, when there is none in the lattice outside the dislocation.
4) “The configuration that the author uses … is not a stationary configuration…”
This referee’s statement is true. However, non-stationarity does not invalidate the result, any more than the non-stationarity of cosmological solutions in GR, invalidate GR.
The manuscript (constraint m << r in Table 2 in section 5.1) states that the present computation is valid only if the distance between Kerr masses is sufficiently large.
Here is why non–stationarity does not invalidate the results in the manuscript.
a) My configuration of Kerr masses starts with zero relative velocity. Therefore a finite time interval will pass before the attraction causes the Kerr masses to get so close that the computation requires additional terms. Throughout this time interval, translational holonomy (before the continuum limit is taken) and torsion are present.
b) We can do the computation in an expanding universe, so the torsion appears before the configuration begins to contract. I did not do this computation because argument (a) is adequate, and because adding expansion would make a complicated computation more complex.
5) Definition of translational holonomy
This definition applies to structure groups that are inhomogeneous linear groups (groups that include translations).
5.1) Development of curves
“Development of a curve” is defined in section 3.1 of the manuscript. See also references [1] page 98 and [2] page 131.
The rationale for development of curves is to distinguish the influence of manifold geometry and acceleration of a curve.
5.2) Definition of translational holonomy in terms of development of curves
Section 3.2 of the manuscript contains a theoretical and procedural definition of translational holonomy in terms of development of curves into Euclidian space.
The basic idea is to develop a spacetime loop into a Euclidean space, and use the “failure-to-close” vector of the “almost–closed” loop in Euclidean space to define the torsion translation in spacetime.
6. References
1. Geometry of Manifolds, 1964, by Richard J. Bishop and Richard L. Crittenden, Academic Press. For physicists, I recommend [1], which is more geometrical and intuitive, over [2] which is more abstract.
2. Foundations of Differential Geometry, vol 1, 1963, by Shoshichi Kobayashi and Katsumi Nomizu, John Wiley and Sons.
3. Transformation groups in Differential Geometry, 1972, by Shoshichi Kobayashi, Springer Verlag.
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Can someone please point me to where an explicit computation of the critical dimension of superstring theory in the RNS formalism is done? Preferably a calculation involving the commutator of the Lorentz generators.
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You should get your answer in standard books (eg. Green, Schwartz, Witten), however you may have a look at the following online material from NIKHEF; it includes a fairly rigorous derivation of central charge and critical dimension, and also the relation a=(D-2)/24
Introduction to String Theory, by A.N. Schellekens
tps://www.nikhef.nl/~t58/StringLectures2014.pdf
Section 3.9
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Within the most general linear axions Einstein Maxwell dilation model(EMD), translational and rotational symmetry are both broken. Recovering translation invariance is not as much as simple to restore the rotational one. For the latter it is enough to set the condition Yx(φ)kx2=Yy(φ)ky2 while for the former it is not so straightforward.
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Also see this Ph.D thesis, from Universidad Aut ́onoma de Madrid, by Amadeo Jim ́enez, which discusses various ways of symmetry breaking in Holographic models, Spontaneous breaking, Anomalous breaking, transport phenomenon and so on, http://inspirehep.net/record/1607633/files/fulltext.pdf
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Is there an alternative theory that accommodates mind and matter? After all, the universe we observe has a logical structure that the mind can understand. If we do not understand something, it must have some measure of illogic. Can we unify all known theories...String Theory, SR, GR, QT, MOND, Standard Model, Big Bang, and so on. Is it possible to unify mathematics and physics (not in the sense of one can explain the results of the other) but in the sense of principles that govern the two? Can science explain miracles, TIME, SPACE, the forces of Nature? Why is gravity? Was Einstein right? Is a complete theory of nature able to explain even notions of God? There is such a theory. It starts with understanding how the mind processes information. Read Book 1..
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If "feeling" and "consciousness" are ignored, I think mind and matter could be accomodated in a single theory framework. In contrast, we indeed never assign "consciousness" to matter, and henceforth, the origin of the entire hardship of our concern obviously.
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What is the most interesting and powerful application of Group Theory?
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Find some interesting applications of group theory in the following link:
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In reference to the attached presentation material regarding the sum of the following infinite series 1+2+3+4+... the following comments are due
• The obvious answer is a huge positive whole number beyond our imagination
• But what if a theory wants the answer not to be so?
• Are we allowed to challenge the theory?
• Are we allowed to bend the rule or even cheat to get the desired value?
• Is this bending, of the rule, only applies for exceptional cases or can be exercised freely?
My conclusions are
  • It is a well-known fact that how feeble tricks are used in mathematics to obtain some haphazard values from divergent series to baptize certain theories in physics.
  • Three types of tricks are used to obtain the desired results
  1. Ignoring or hiding divergent quantities
  2. Ignoring or hiding conditions for formulas
  3. Extending the domain of a formula
  • These tricks simply erode confidence in mathematics as a sure scientific tool.
  • It is a legitimate question that if these flagrant deceptions are exercised to fool ourselves, who knows what other tricks are used to obtain desired results from complicated mathematical derivations?
The main question is; why for heaven’s sake, mathematics needs cheating in dealing with new challenges in science. Either it is not competent enough to cope or it is just a subjugated slave in the hand of any popular theory
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Ziaedin Shafiei Dear Ziaedin,
The problem depends on how one defines and accepts a trick. If we understand by a trick a "skillful act" that can be put in simple sequences of logical steps, then it is a mathematical act. If we understand by a trick an act intended to "deceive or mystify" others or oneself, then this clearly cannot be accepted. The problem is accepting illogical ideas put in deceptive bright capsules.
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I was very excited about the potential of the AdS/CFT duality to link physical phenomena to models in string theory, especially quantum gravity. Indeed, I was very interested to pursue my Master thesis in this subject.
However, I was wondering if doing research in this area would be to risky as there are even fewer post-doc positions in this field, since string theory seems to be slowly losing support after the experimental data at LHC. In particular, I like both the mathematical formalisms of theories and the experimental confirmation of models, and I would like to involve at least some computing in the mix.
Should I still pursue this field or it would be safer to switch to something more concrete?
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I'm a postdoctoral researcher and I have been working with the AdS/CFT correspondence for the past 5 years.
Personaly, I don't think that the AdS/CFT can be used to make precise predictions about the real physical world, but I do think that it provides us a large class of toy models that we can use to learn a few things about the physical reality. Let me give you a few examples:
- the most known example of AdS/CFT correspondence is the duality between the so-called N=4 super Yang-Mills (SYM) theory and type IIB supergravity. As you probably know already, some quantities that are very hard to calculate in the SYM theory can be easily calculated in the gravitational description. So, intead of doing complicated calculations in a very complicated quantum theory, you can do some classical calculations in the gravitational description.
One of the first pratical applications of the AdS/CFT correspondence was its use to study the quark gluon plasma (QGP) formed in heavy ion collisions. Of course, the plasma formed in such collisions is in principle described by QCD, but there are a lot of physical quantities of the plasma that cannot be studied (or are very hard to study) using the framework of perturbative or lattice QCD.
One possible approach to this problem is to use the N=4 SYM as a model for QCD and to do the calculations using the gravitational description provided by the AdS/CFT correspondence. The N=4 SYM theory does not describe anything in the real physical world, and indeed is very different from QCD. However, when one considers both these theories at finite temperature, they are not so different after all, and there are some universal quantities that do not depend very much on the specific model that one considers. So, when you use the AdS/CFT to study the QGP, you are not studying the real-world QGP, but you are actually studying some other 'plasma' that is not so different from the real thing. So, I guess what I'm trying to say is that the phylosophy here is that you have a toy model, from which you hope to learn something about the physical reality.
With these approach people have proposed, for instance, that the shear viscosity of the QGP should be very small, and this indeed was confirmed by the experiment.
There is also a similar approach involving applications of AdS/CFT to study condensed matter systems.
The AdS/CFT duality has also provided inspiration for several other developments in the theoretical physics, for instance:
(1) the development of a hydrodynamical theory in the presence of conformal anomaly;
(2) a brand new description of quantum chaos;
(3) connection between gravity and information theory.
The last two topics are very popular right now. In (1) and (2), the first calculations were done using AdS/CFT, and this inspired some developments which did not rely in the existence of a gravity dual.
Some people might say that AdS/CFT might provide a precise description of reality, but I personally don't know whether this is true. My phylosophy is to consider AdS/CFT a toy model and use that to learn something about the physical reality. From my experience in the field, I can say that this approach has been very successful and it is still very popular. Note that with this phylosophy it does not matter whether string theory has experimental confirmation or not, because you're just using it as a toy model.
Regarding the number of postdocs in the field: I think there is a decreasing number of people working exclusively with string theory, but there is an increasing (and already large) number of people working with AdS/CFT (the two communities are not necessarily the same).
All the best,
Viktor
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unification theory, string theory
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i follow
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In other words, if you project the ten-dimensional space of string theory onto a four-dimensional space-time, is the resulting space-time, which will have an uncertainty principle in the coordinates at the Planck scale, accurately represented by a spin foam?
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I don't enjoy the aggressive tone used by many contributors to blogs on RG. I believe that people who know me do not blame me to be arrogant; and I don't think that I am particularly stubborn. I actually only try to sometimes comment on questions. People who do not like my comments are not obliged to study them! I am retired, and I do not have to make a career, anymore. But sometimes I am still thinking about science, and I am interested in upholding intellectual honesty. (There are no benefits to be gained from kidding oneself into believing that certain problems are understood or, at least, promise to be understood, soon, when they are very poorly understood.)
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What is the possibility that I'll get a PhD job for research in String Theory and Particle Physics? I'm currently in my 3rd Year of Undergraduate Studies and have done research work in Photonics. Due to unavailability of faculty specialized in relativity, cosmology, particle physics etc., I chose to do research in Photonics. To manage my interests, I studied relativity, particle physics from online resources. What are the chances that I'll get a PhD job at institutes like Perimeter Institute of Theoretical Physics, Institute of Theoretical Physics, Stanford, Kavli IPMU etc.?
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Before you start investigating textbooks and study programs in fields of science, you should seriously contemplate whether you want to invest your life and talents in these areas.
The Standard Model of Particle Physics were completed in the mid-1970's. Try to explore which new, experimentally verified, ideas have emerged in the field of theoretical particle physics since then. Likewise, string theory was invented in the late 1960's and superstring theory during 1970's. Try to find out what these theories have contributed to observed physics.
The recent discovery of gravitational waves have opened new ways to explore cosmology and astro(particle) physics. This will hopefully lead to new insights and increased activity, both observationally and theoretically.
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My theory gives a solve to gravity and the rest of forces on the universe. Only can be a unificated theory of everything. 
At this point this is in draft so there may be many questions and are welcome.
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Does String Theory provide specific numerical data information on atomic particles such as electron, proton or netron?
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The answer to the question raised is a simple No.
String Theory is not a theory in the sense of a 'physical theory' *). It is a collection of mathematical ideas and promises for the future. From Wikipedia: "It is not known to what extent string theory describes the real world." Nevertheless, there is a lot of public propaganda (“The Elegant Universe”) and hopefulness (in 2001), as expressed by the sentence:
"The successes of the theory depend on a sequence of amazing discoveries that is just not plausible if the theory is an accident, rather than part of the description of nature." (E. Witten: Lecture notes "String Theory", Princeton, Oct. 2001)
Considering that the 'amazing discoveries' are of purely mathematical nature (without any hope of experimental verification), everybody can agree that they are not 'an accident'. But the conclusion that, therefore, they must be 'part of the description of nature' is not based on empirical observations, but rather on this argument: The mathematics is too amazing not to be the real description of nature.
* A physical theory is a model of physical events. It is judged by the extent to which its predictions agree with empirical observations (from Wikipedia: Theoretical Physics). An Advocatus Diaboli could ask: Where are the physical events, where are the predictions, where are the empirical observations, on which String Theory is based.
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The Lagrangian of a tachyonic scalar field T can be expressed as
LT = - V(T)( 1 - du T du T)1/2
When T only varies with the cosmological time t, the energy of density is
rhoT = V(T)( 1 - dtT dtT)-1/2
where dtT is the tachyonic velocity.
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what if the Tachyon is neither matter nor energy but a third kind of entity which is only defined by it's speed being greater than that of light? in my book, which i have uploaded on this website, called, "Musings of a Neurologist", there is a theorem on Tachyon(s). they do not interact with either matter or energy. however, we can know about their existence indirectly. this indirect existence of Tachyon(s) is if we see matter moving at speeds greater than that of light in vacuum. i believe, the astronomers have observed many galaxies moving at speeds that is greater than that of light. they have tried to explain this by saying that if we add up the speeds of the galaxy to the rate of expansion of the universe, then the observed violation is only apparent and not real. however, this goes against the very basic idea of relativity, which says that what you observe is the truth for your frame of reference. also, one cannot use the galilean addition of speeds and the relativistic addition of speeds at the same time. thanks. 
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"In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. It describes how these strings propagate through space and interact with each other."  -- Wikipedia.
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One dimensional objects are not observed anywhere in nature. Strings are just an idea of locations best represented physically as the intersection of two surfaces. Vibration modes can be made to represent fundamental particles, depending on the character of the intersecting sources.
Infinities are not observed in nature either. There is no way to measure them. So in principle the structure of scientific theory cannot be derived from infinities.
The soundness of string theory is debatable. It needs 26 dimensions or a super symmetry of 12 dimensions. A family of Dark Matter particles is essential in the super symmetry, but the Dark Matter particles have not been found. I give the 26 dimensions a better chance of success.
For your question the answer should be no. Infinities do not help a physical theory. 
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Greetings Bianca,
I'm interested in your research interests, several of which closely match my recently uploaded paper: AI Peer Review Challenge: Standard Model of Physics vs 4D GEM EOS. Naturally then I would value your opinion of it.
In particular, I find your interest in an AdS/CFT background independent encouraging--which, as I am sure you are aware, is an interest shared by the Clay Mathematics Institute regarding the Yang-Mills mass gap problem. I'm currently working on a slightly revised Maplesoft Application Center version of the paper, which of course features Python code conversion, wherein I'll also be making reference to the Perimeter Institute Tensor Networks Initiative.
Please consider then the attached 4D GEM EOS paper and its Mathematica code establishes a total field formal frame optimized lattice gauge group in direct accord with the Tensor Networks Initiative.
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Alright Bianca, Dibakar,  et al,
I’ll see ALL YOUR QUANTUM FIELD THEORY TEXTBOOKS…and raise you the 2017 CRISIS IN PARTICLE PHYSICS: “Spiropulu in 2014 compared the current crisis in particle physics to the situation before 1905 when the concept of the classical materialism ether as the medium for all electromagnetic waves could not be verified, stating that if sparticles and dark matter are not detected within the next few years, then radical new ideas will be required.”
[12] M.Spiropulu,TheFutureoftheHiggsBoson,2014.http://meetings.aps. org/Meeting/APR14/Session/A1.2
[13] American Physical Society, Particle Physics Gathering Storm, 2014. http://physics.aps.org/articles/v7/42
Check the calendar, it’s 2017 and radical new ideas are still required—which you will not find in your outdated textbooks or conference proceedings. The current path your 4D quantum geometries and torsion project is on is not going to solve anything either, since the dirty little secret (DLS) of the prevailing theories of modern physics is all your “explanations” ultimately depend on “hidden dimensional unknown material mechanisms”—all of which are conjectured to act by unobservable AdS/CFT background in direct contradiction to the observed forces you claim to be describing!
Scandalous. For example, Bianca, Dibakar, et al, find the sections in your textbooks where the strong nuclear force is said to act by the unobservable AdS/CFT background of quark-gluon-quark fluxtube continuous emission-carrier-absorption. The fundamental contradiction being it is always observed any such emission-carrier-absorption always results in a repulsion from any would-be line of attraction.
Note the opposite of quantization and reproducibility is divergence…and now in the 2017 CRISIS IN PARTICLE PHYSICS the entire Standard Model of Physics is diverging en masse into Supersymmetry sparticles…all of which are zero-dimensional (0D) imaginary-invisible mathematical point particles having the 4D spacetime measurements of nothingness…containing all of your Tensor Network Initiative 4D quantum geometry torsion project hidden dimensional unknown material mechanism compounded ethers…all of which, so you say, exploded from the original Big Bang 0D mathematical point having the 4D spacetime measurements of nothingness…before spacetime existed! If you are looking for just how to characterize the source of the 2017 CRISIS IN PARTICLE PHYSICS…there you have it.
The problem with dark energy is it’s difficult to assign yet another compounded hidden dimensional unknown material mechanism to “explain” dark energy because that indicates everything is connected just like in rejected pilot wave theory.
The fundamental multiverse self-contradiction by self-definition is an “infinite number” of random unobservable disordered universes are conjectured to “explain” the observed finely-tuned ordered universe.
Multiverse theory is a bait-and-switch scientific con game—starting with its “infinite randomness” conjecture: In an “infinite number” universes anything imaginable (e.g., a “miracle” cure of all ALS cases) has a 100% probability of occurring in an “infinite number” of so-called “trivally real” parallel universes.
Infinity being the bait is of course not a number, so infinity must be switched out for some number: 10^(400) universes says Hawking, no no there are 10^(500) says Linde re their Higgs Boson Doomsday conjectures. Notice however switching infinity for some number—pulled out from wherever…constitutes semi-intelligent design. Nevertheless that is what all of your promising Phd careers are based on right now.
Thus hidden dimensional unknown material mechanism multiverse pseudoscience constitutes the most sophisticated and longest running con game in history, wherein the 10,000 CERN LHC physicists are paid to speculate!
Funny story: When I was an undergraduate intern at the Lawrence Berkeley Laboratory, Nuclear Science Division, I asked my mentor, Dr. Hans Georg Ritter, Director of the Theoretical Physics Group, “How is it you think the virtual quark-gluon-quark interaction—in its virtual state—carries the attractive strong force, contrary to the always observed repulsion of emitter-absorber pairs from the would-be line of attraction?” He answered:“Everyone makes their own little toys to explain it.” I thought it was the best answer he could have made, except I didn't like those toys. I didn't want to play with those toys, which never worked like they say they do anyway.
The point being Bianca, Dibakar, et al, right now all you are doing at the Perimeter Institute Tensor Network Initiative 4D quantum geometry torsion project is constructing yet more fatally-flawed imaginary toys that will never work = CONTRADICTION BY AI FAILURE.
Sadly the Perimeter Institute Tensor Network Initiative is the closest match I’ve found to the radical new idea of my 4D GEM EOS optimized lattice gauge group spin-stress pressure tensor wavetrain integrations group operation—leaving me more convinced than ever the only way to prove the conjecture (other than just by clicking through the Mathematica code) is by AI-ATP Peer Review.
Once added to the Mizar corpus, Standard Model researchers, such as at the Perimeter Institute, could then modify the conjecture python code to attempt to find your infinite variations of hidden variables—if the Perimeter Institute has any interest in actually doing so. I rather doubt that though. Like the growing list of Phd’s before you, I’ll wager you are thinking about deleting these comments right? Talk about it first.
OK fine, at this posting there’s only been 16 project reads. So I’ll just sign-off with the following all upper-case conclusion:
IN THE BEGINNING OF THE PERIMETER INSTITUTE, TENSOR NETWORK INITIATIVES, 4D QUANTUM GEOMETRIES TORSION PROJECT WERE THE ASSUMPTIONS…AND THE ASSUMPTIONS WERE VOID.
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we will try to write matrices whose obeys to some algebra to describe the graviton. is that is possible? if your answer is no, why ? 
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"Can we write Dirac equation with replacing gamma matrices with others that we construct in the aim to describe graviton?"
Yes, it is possible (but not simple!). The Dirac algebra corresponds to spin-½. The Kemmer algebra corresponds to spin-1. The graviton (if it exists) would be a massless spin-2 particle. There is a general theory of “spin-s” field equations (see for example Corson’s book https://archive.org/details/IntroductionToTensorsSpinorsRelativisticWaveEquations.
investigated the spin 3/2 and spin-2 algebras.
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Erik verlinde said; this emergent gravity constructed using the insights of string theory, black hole physics and quantum information theory(all these theories are struggling to take breath)..its appreciation to Verlinde of his dare step of constructing emergent gravity based on dead theories ..we loudly take inspiration from him...!!!!!!!
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@ Adrian Sfarti ;;
my dear Adrian Sfarti do you have any objection if i comment? arey faltu he constructed his theory on string theory go and read once again empty vessel...
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Just read "Inflation and the Measurement Problem". If I understand correctly, they proposed a model with interaction between Fourier modes. By tuning parameter one will obtain Harrison-Zel’dovich scale-invariant
power-spectrum as well as Gaussian Random field. What I don't understand is that I think it still need measurement to form a classical field configuration. Did I misunderstand it?
Thanks for answering.
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I am doing project in Quandles . And I am reading Thesis by David joyce An Algebraic Approach to Symmetry with Applications to Knot Theory . In its Section 4.5 Knot quandles page number 46 there is a line " when a loop in X-K links once with K " , I am not getting what it means . And after that knot quandle is defined as nooses linking once with K upto homotopy which is also not clear to me . I have not done course in Algebraic topology and knot theory but I have read fundamental groups myself . If possible please explain through figure.
Any type of help will be appreciated.
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See the activities of V. O. Manturov
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Can I find a mathematical model of vibration phenomena where the speed of propagation is missed, or unknown for some reason ?
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All discrete objects in the universe are modules or modular systems and all modules are observers. Sets of elementary modules exist that configure all other modules. These elementary modules. Does their way of observation represent consciousness? If the answer is positive, then this form of consciousness is certainly the most primitive form of consciousness. All observers receive their information via vibrations or deformations of the continuum that embeds them. Elementary modules receive that information in the most primitive way.
Elementary modules are pointlike objects. Physics knows them as elementary particles.
Elementary modules are represented by coherent and dense swarms of clamps. These swarms contain a huge number of elements. Each clamp carries a standard bit of mass. The clamps represent the most primitive form of matter.
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I think that the most primitive form of consciousness is humanity. It exists among all creatures. Its vibration harmonizes with nature and transmitting in the universe without fading. It links with the rightness Qi and nourishing particles.
There are tangible world and intangible world coexist in the universe. The intangible world regulated the tangible world with invisible power. However, this power is hard to be noticed if anyone refuses to recognize its exist. If only study the tangible world, the wisdom is limited and leave many mysteries without explained. If put both of the tangible and intangible into consideration, wisdom generated, time-test solutions coming out that solve the real-world problem from the root level. It does not harm the other creatures and can last long to pass the time test.
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Should time be considered continous or are there definitions for a time quantum (e.g. shortest time for anything to happen)?
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Newton and Einstein's theory treats time as continuous flowing in one direction from past to present to future. In my theories I consider this as imaginary time. And since space time are not independent of each other, both are imaginary. The reality is based on wavelengths and periods of the particle waves. So time is periodic in nature. Definition of this periodic time quanta comes from de Broglie formalism as discussed in following article. The shortest time for anything to happen is Planck time 10^(-43) sec. When the period of the wave gets any smaller than this, it crosses the compton limit on wavelength 10^(-35) m. and this will make the particle wave to collapse leaving no mass gap. So energy of the particle will become perfectly motionless.
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Regarding my understanding string theories — type I, type IIA, type IIB, (heterotic) SO(32) and (heterotic) E8×E8 — to one another and to eleven-dimensional supergravity (a particle theory). The discovery of these connections led to the conjecture that all of the string theories are really aspects of a single underlying theory, which was given the name ‘M-theory’ (though M-theory is also used more specifically to describe the unknown theory of which eleven-dimensional supergravity is the low energy limit). The rationale, according to one kind of duality (S-duality), is that one theory at strong coupling (high energy description) is physically equivalent (in terms of physical symmetries, correlation functions and all observable content) to another theory at weak coupling (where a lower energy means a more tractable description), and that if all the theories are related to one another by dualities such as this, then they must all be aspects of some more fundamental theory. Though attempts have been made, there has been no successful formulation of this theory: its very existence, much less its nature, is still largely a matter of conjecture.
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as string theoreticians saw that the theory isn`t completely they introduced more dimensions, branes, m-branes; nonstandard Analysis (where a*b=-b*a) and so on. string theory won`t sove the Problems physicians have (that`s what I Postulate) 
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Professor F.Ngakeu has stated in his important article "Levi-Civita Connection on Almost Commutative Algebras" that the coefficients of Levi-Civita of example 3.8 is a consequence of theorem 3.7. How can I obtain those?
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Yes, there is a free pdf of paper on google.
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Dynamics in the complex space to describe the quantum dynamics is  a very interesting approach. In the other hand, classical control is a strongly develop theory. Is it possible solve Quantum control problems using complex dynamics? Any reference? any advice?
Your descripción,  Is it related to Clifford algebra?
Thanks and congratulations for your works
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As pointed out above, the fundamental difference between Quantum and classical mechanics is the algebra of the obervable operators. Classical mechanics in the Hilbert space was introduced by Koopman and von Neumann.
In this way, the classical equation of motion is linear and very similar to Liouville's equation. The price to pay for having a linear equation of motions is that it becomes a partial differential equation, which is in most cases more difficult to solve. This represents an important challenge at the time to apply control. Nevtheless, it is possible as shown in one of my preprint publications.
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Proposed in late 1997, this correspondence is a theoretical result which implies that M-theory is in some cases is equivalent to a quantum field theory
  • How does one show the equivalence?
  • What is the structure of this quantum field theory ?
  • Is it a 4 dimensional local gauge model ?
  • Are there any phenomenological implications ?
  • What is anti - deSitter space ? Is there a set of transformations from Cartesian coordinates ?
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The AdS/CFT correspondence is one of the largest areas of research in string theory. AdS/CFT stands for Anti-de Sitter/Conformal Field Theory, an expression that’s not particularly elucidating.
AdS/CFT is a particular, and deeply surprising, example of a duality. It relates two very different theories and at first sight seems obviously wrong.
It states that there is a duality between theories of gravity in five dimensions and quantum field theories (QFTs) in four dimensions. This correspondence was first formulated by Juan Maldacena in 1997, and is generally thought to be the single most important result in string theory in the last twenty years.
The original example of AdS/CFT linked two very special theories. The gravitational side involved a particular extension of gravity (type IIB supergravity) on a particular geometry (5-dimensional Anti-de-Sitter space). The QFT was the unique theory with the largest possible amount of supersymmetry. There’s a specific dictionary that translates between the theories.
This relationship has no formal mathematical proof. However a very large number of checks have been performed. These checks involve two calculations, using different techniques and methods, of quantities related by the dictionary. Continual agreement of these calculations constitutes strong evidence for the correspondence.
The first example has by now been extended to many other cases, and AdS/CFT is more generally referred to as the gauge-gravity correspondence. Formally this is the statement that gravitational theories in (N+1) dimensions can be entirely and completely equivalent to non-gravitational quantum field theories in N dimensions.
The AdS/CFT correspondence has a very useful property. When the gravitational theory is hard to solve, the QFT is easy to solve, and vice-versa! This opens the door to previously intractable problems in QFT through simple calculations in gravity theories.
Moreover AdS/CFT allows a conceptual reworking of the classic problems of general relativity. Indeed if general relativity can be equivalent to a QFT, then neither one is deeper than the other. Finally physicists can use it to develop new intuitions for both QFT and general relativity.
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In my paper in Phys. Letts..vol 68A (1978)409-411, I have discussed a metric
projectively related to Friedman/R-W metric with identical geodesics.Questions:
Are there other such solutions for this case or for other conformaly flat
spaces? One such solution defines an infinite succession. Is there a computer
program to find infinite succession of (covariant)Einstein tensors.; the
change represents the erruption of matter-energy in assumed spontaneous
projective change. on approach to a singularity. Physically the change is
caused by intervention of Gauge fields to avoid gravity-induced collapse.
The point is that addition to Christofell connection of a term (Identity tensor
times Vector) leaves a system of geodesics unchanged,and is in accord
with equivalence principle. This way one can relate both gauge field and
Q.M. with G .R..Details on request.See also Matsience Report no92(1978)/
paper 9,14pp (www.imsc.res.in/Library)-Black Body Structure of a Black
Hole. And  Lie Structure of Quasiconformal Maps in R*(*=N). And Physics of
String Theory in Quantum Field Theory. QM,& Optics- Ed VV Dodonov &
V I Manko , Moscow (1990) Nova Publishers (N,Y)vol 187 of Proc 0f Lebedev Phy. Inst.Acad. 0f Sciences 0f the USSR./pp113-116..
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Your interesting general question reminds me of my more specific question of whether or not someone is strong enough to write down the field equations in such a way that the speed of light c is a global constant (and not just an everywhere locally valid constant)?
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L= r x p is a 3 dimensional relation. In 4 dimensions r and p are 4 vectors and L is a 4x4 matrix. We want to discuss conservation laws related to angular momentum in 4 space time dimensions. Then discuss the issue of angular momentum of a Black Hole.
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For the Kerr (-Newman) black holes this is given by the Komar integral belonging to the Killing field, associated to the SO(2) isometry group. For details, see e.g. my GR- book (Springer 2013), eq. (8.187).
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The string detained between two points can sustain harmonic motion.  At the string midpoint, the potential and kinetic energy are inverse, so that when the string is in the mid-line, the kinetic energy is 1 and the potential energy is 0. When the string is at the boundary the string stops for an instant, so the kinetic energy goes to zero while the potential energy is 1.
A node is defined as a point on a string where there is no movement possible, so that both the kinetic and potential energy are zero.  The fixed-point theorem says if pitch is a real function defined on [0, 1], then there must be a fixed point on the interval.
Since the kinetic and potential energy is just the result of basic trig functions sin and cos, it seems clear to me then that wave reflection cannot occur at the string endpoints.  The endpoints are fixed points which are in effect fulcrums with a fixed-point position so that length L = 1 is a bound variable.  The fulcrum allows the fundamental in the monochord to drive the string on the other side of a node, but the condition for wave reflection does not exist at the node. 
When a sin wave crosses zero there is no requirement that the point is fixed, so the boundary cannot simply be added to the wave function arbitrarily without changing the nature of Fourier analysis.
If the waves reflect at endpoints, do they also reflect at nodes that are not enpoints? Of course not!  But then, in the 1/3 mode, what makes the middle wave where there are 4 nodes and 3 waves?  Is the middle wave the reflection of 2 traveling waves between the two non-endpoint nodes?
The boundary condition for traveling wave reflection is 1, 0 , 1 which is clearly a false statement.
Significantly, the frequency and the wave length are bound by the string and not free variables subject to real analysis as continuous variables.  Nodes and waves cannot add at the same point.
If physicists really think there are two traveling waves on a string moving in opposite directions that make a standing wave, but no one can see or demonstrate these waves, then maybe they have action-at-a-distance wrong, too.  After all, the basic error is assuming frequency is continuous, and then using functions with free variables adjoined with arbitrary integers.
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But in the typical reflection the kinetic energy goes to zero at the wall while the potential energy is at a maximum so there is a force that explains the reflection,  If a wave travels down a funnel it does not reflect.  So I say these imaginary traveling ways are nonsense.  Where is the equation of motion if the wave is standing?  Where is the stroboscopic image of these two waves that some how reflect to make one.  There is a curve lifting function between the string at rest and the string in wave form that is point-for-point so the only force vectors are orthogonal to the string axis.
Statements about the string without quantifiers are provable.  Can you prove there is a mode lower than the fundamental with wavelength 2L? Of course not.
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i would like an answer from experts in string theory, quantum physics...
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This Is a good question with many possible answers.
Let A be an n-dimensional geometrical figure represented by.a set
of points on an n-sphere S^n (hypersphere). And let
f: S^n --> R^n be a continuous mapping such that f(A) is a
feature vector that describes A, e.g.,
f(A) = (area(A), diameter(A), ...) in R^n
Then represents (describes) A.
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I think it is clear classic string theory is defined in Z2, if only because waves are 1 and nodes are zero. 
If we assume the string waves and nodes are defined in Z2 as a deductive system, the fundamental is defined on the interval [0, 1] with the wave boundary condition 0, 1, 0 and the identity of the fundamental is [0, 1].
In "Ideals, Varieties, and Algorithms" by Cox, Little, and O'Shea (Springer, 2007) the F2 = {0, 1} field is described, but I am having trouble with the way that multiplication and addition are defined.
I would like to know if this is the only way that addition and multiplication in the F2 field can be defined.  Or, is it possible the way it is in the text is a natural representation of the string wave boundary that I don't get?
The book says these are the rules for F2:
0 + 0 = 1 + 1 = 0
0 + 1 = 1 + 0 = 1
0 x 0 = 0 x 1 = 1 x 0 = 0
1 x 1 = 1
But it seems more like it should be;:
1 + 1 = 1
1 x  1 = 1
The reason I think this is because if we add two waves we get a new mode.  If we add two octaves we get a new octave.  If we add two strings we get a new unit. The 1 + 1 = 1 equation describes the behavior of projective sets and other topologic sets like algebraic fields (and I think nullstellensatz).  If two closed sets can form a closed union and intersection, then they make an arrow with a 1. Or just a 1.
I want Z2 to be the the principle ideals of the algebra of the string.  The string is the union, intersection, and complimentaion of two disjoint sets (which are the pitch and position set defined on the string).
I think that since the boundary and matrices for [ Z2]n cannot add or multiply if the dimensions are not equivalent, this shows waves with different dimensions do not add.
The string has to be an integral domain and not the sum of an infinite series.
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No, sorry, most of this does not make sense to me.  The bottom line is that there is no way you are going to make the two-element set F2 into a field with operations + and * that are the same.
If you are trying to model the notes in an octave via an interval on the real line and you want to identify notes that differ by an integer number of octaves as the same, the natural way to do that would seem to be the quotient group R/Z (the real numbers modulo the integers), which is isomorphic to the circle group S1.  Note that this is only a group, though, not a field.
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In classic string theory the string vibrates in multiple modes of vibration so that the string is the sum of all the possible modes that are demonstrated using the monochord.
For instance, I was taught that plucking the string and then detaining the string at the 12th fret shows that the first octave harmonic is inside the string and merely revealed by dampening all the other modes of vibration.  That implies the string has 2 states of system at the same time.
Classic string theory then implies that the string can have many different fundamentals at the same time so the state of system of the string is not a constant but an infinite series. 
It seems more likely that the string always vibrates in the lowest mode and can only  be forced into a higher mode by an additional point of detainment.  The third point of detainment creates a new fundamental.  Only the octave is true, the higher overtones are not in the diatonic order and do not have the metric of the octave.
Since we know by Euler the string is detained in a concatenation (not a sine wave), it is not possible that the higher modes of vibration can co-exist with the lowest mode.  This is clear at the string ends (the angle of deformity is greater with higher modes), as well as at the nodes which cannot co-exist without cancellation.
Since the concatenation is not a sin wave it is clear the string mode of vibration and the sounded emitted in radiation are orthogonal and independent.  If the string emits frequency that is not the fundamental, then those vibrations are not defined in the musical state of system; they are incidental and have some other fundamental that has no simple arithmetic  relation to the tone value system. 
Absurdly, many authors claim that vibrating string is an example of the string theory of closed and open strings.  Many experts say the wave moves along the string over time, apparently because this allows the introduction of trigonometric functions.  (If we assume the frequency domain is a sin wave then it looks like the trigonometric functions are the elemental property of music but this violates the principle of spectral resolution in which frequency is a winding number but defining points between frequency cycles calls for an assumption. Assume frequency is a sine wave, then pitch is a sin wave, too. But frequency must be a 1 or a 0 in measure theory.  1 is a homomorphism which is not a function of time.
It seems to be overlooked that music is a theory of strings that are at once open to polyphonic union and closed by the octave.  Strings are clopen and nonreducible, so we cannot separate the pitch from the string state of system. This is not the modern string theory where strings are either open or closed, but not both at once. The problem of how the string is a musical set is resolved in projective space where lines are always circles too.  The natural overtones are not a closed system, and to make 12-tones you have to go to many higher partials.
It seems clear then that neither classic or modern string theory applies to music theory.
Is there some well-respected official of modern or classic string theory who wants to try to revive classic string theory for music? Or can we agree the 300 year-old theory of the musical string is dead?
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The wave equation is an equation, for the amplitude of vibration, which is a function of position and time. What the wave equation expresses, is a relation between the spatial and time derivatives of the amplitude. So to solve this equation means to search for a function of position and time, whose derivatives satisfy the appropriate condition. Now an arbitrary function of position isn't, necessarily,  an eigenfunction of the spatial derivative operator (defined on the space of functions that satisfy the boundary conditions appropriate to the problem), which is a linear operator. Therefore it can be expressed as a linear combination of the  eigenfunctions of this operator, that are called, in this context, the modes of vibration. Since the spatial derivative and the time derivative, defined as operators that act on the function space referred to, can be shown to commute, it's possible to expand the amplitude in a basis of functions that are common eigenfunctions to both operators.
If the wave equation is a linear equation, then each mode, also, is a particular solution of the wave equation. 
That's all there is to it. 
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Can the dynamics in concentrations, structures, interactions and location of all the entities in the produce cellular states defined as state of "energy" with extra-dimensions?
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They need not be, but, indeed, what matters is that the scale, where they're relevant, is that where gravitational effects become comparable to quantum effects, which is much smaller than the scale of the cell, where electromagnetic effects dominate.
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Doing a comparison with special relativity for example, the event is described by a point which has four coordinates in space time, but string is what? And came from what ?
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In elementary particle physics, particles assume zero volume, that is they are point particles. If uncertainty in position is zero, then uncertainty in momentum is very large. Therefore, while calculating amplitudes of physical processes, one has to integrate over momentum from zero to infinity. The physical cross sections therefore diverge. One has to then renormalize the theory.
One may ask whether it is possible to get rid of this problem by considering particles as extended objects such as strings. Strings are not points, but they are one dimensional objects living in more than four dimensions. We know that a particle sweeps out a world-line when it moves in 3D. In a similar manner a string sweeps out a world sheet. Which is a two dimensional surface. Space time coordinates Xμ (μ=1,2,..10)  are functions of world sheet coordinates, that is, they are described as scalar fields Xμ(σ,τ) . They are determined by a two dimensional field theory defined on the world sheet. One such (2D) field theory model is given by the Nambu-Goto action.  Another more sophisticated model is given by the Polyakov action. In this way space-time coordinates (including the compact ones) are dynamically generated in a string picture.
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Physics has a lot of abstracts like energy, or momentum that are properties of something. Is there a something equivalent for strings? Something that can be related back to what I can sense directly even if the story is a long one.
Or are strings a new invention whose value is in its explanatory power?
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Strings represent a theoretical concept possibly useful to provide a mathematical description of a certain subset of natural phenomena. Modern physics does not talk about "substance" (such as ether, heat,...), anymore; i.e., we do not ask what things like particles, fields or strings are made of. Instead, these notions refer to theoretical concepts that appear as mathematical objects in some of our theories. The success of these concepts is gauged according to whether those theories yield accurate descriptions of natural phenomena, or not. - For the time being, string theory isn't really a THEORY, but, rather, a surprisingly coherent set of rules enabling the experts to perform many amazing calculations and mathematical operations. It retrodicts a large set of physical phenomena from a fairly unified point of view; but it has not made any specific predictions that could serve to prove it wrong or right.
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Any physical phenomena that occupies space in time has to be described by coordinates and the optimal minimal number of coordinates required for this description determines what is called the dimension of the space-time in which the object is and properties of this physical phenomenon can be studied either as evolution along its temporal axis or by its spatial behavior in terms of rates of change across the coordinate axes. One of the fascinations intuitionists of string theory create is the claim that space is not actually 3+1 dimensional but is of higher than that.
The intuition is that a one dimensional linear string from a distant when observing up close yields a three dimensional feature than one dimensional and therefore all the three dimensions we all know extrapolated to generate 9 dimensions of space with new six extra invisible dimensions that are curled to be seen. But if these somehow intuitively sensed dimensions which need to have variables of curled coordinates are not detected and manifest themselves during mathematical descriptions of positions and behaviors in time or independent of time, then either they do not exist at all and mere intuition or the formulations of differential equations we all along use to describe fundamental laws of physics are not formulated correctly and incomplete.
If their existence is very small (minimally small to the extent of not being observed), then unlike the usual coordinates and the usual derivatives, we might create another structural concepts in mathematics to incorporate such existences. But giving a mathematical meaning to something which does not exist is a mathematical paradox and loses it place in mathematics it self and therefore in reality. In line with this,Tom Morley puts in his short article (see attachment below) that space is 3+1 dimensional and I put the question in line with his arguments.  
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This is a very interesting question with lots of possible answers.
A place to start in looking for answers to this question is in
Sujan Dabholkar, Exploring Warped Compactifications of Extra Dimensions, Ph.D. thesis, Stony Brook University, 2014:
In this thesis, we have higher-dimensional views of the universe, e.g.:
5D view: 5-dimensional Minkowski space M5, the Anti de Sitter (AdS) Universe is a hypersurface, p. 67.
7D view: This 7D view results from considering Buscher rules along z direction.
1D, 2D, 3D and 4D views of space-time are considered in
Maroun, Michael Anthony, Generalized Quantum Theory and Mathematical Foundations of Quantum Field Theory, Ph.D. thesis, UC Riverside, 2013:
See Section 5.1.1., starting on page 72, on counting the dimensions of space.
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I want to accelerate my research in topological quantum field theories, I know that in N=1 super Yang-Mills there is conformal twist, but how to get to obtain topological twist in this case is actually my problem, does somebody have any idea?
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Dear Nounahon,
                               I would suggest you take a look at my papers on Haag Theorem and Politcial Environment and Stock Markets papers on my RG page. They might be helpful. Although I do not know what exactly you mean by topological twist is it conformal flows or heterotic flows that you are looking for? SKM QC FEPS(D)
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We know that Classical Mechanics can be shown as special and approximated case of General Relativity and Quantum Mechanics.
Is the case similar here?
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No. We do not have even a consistent theory for quantum gravity(and it seems probable that Einstein's theory cannot be quantized at all)
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I was wondering about the AdS/CFT correspondence basics. It is constructed on the idea of conformal compactification, in which a open manifold M is homeomorphic related to a closed one N through a conformal transformation of both metrics. The open manifold acquires a conformal boundary in which the conjecture is stabilized. If one thinks on the Index Theorem, a single issue appears: a pseudo differential operator (e.o.m) on the topological boundary does not have a well defined index, so would not be possible to extend the idea of holography to closed compact spaces?
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In general, one can have a holographic correspondence for open manifolds. Maldacena conjectured that all information of a string theory in AdS_5\times S_5 is contained a 4d N=4 Super-Yang-Mills theory. The correspondence can be reasonable generalized only for few other cases. The particular case that I have mentioned is substeined by calculations' tests, but it was not demonstrated.
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The graviton is a hypothetical elementary particle that mediates the force of gravitation in the framework of quantum field theory. If it exists, the graviton is expected to be massless and must be a spin-2 boson. The spin follows from the fact that the source of gravitation is the stress–energy tensor, a second-rank tensor. But by no means is it universally accepted.
But there are many articles about the interaction between Photon and graviton or graviton-photon scattering.
How can graviton's mystery be solved?  Should graviton be detectable or like photon (same as photoelectric effect) be able to explain the physical phenomena?
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Gluons don't interact-directly-with photons, because gluons don't  carry electric charge and photons don't carry color, the charge of the strong interactions. Of course, since gluons do interact with quarks and quarks do carry electric charge, also,  it is possible to describe an effective gluon-photon interaction this way and is a standard calculation. While electromagnetic waves are affected by variations of the spacetime metric, an example being bending of light, the weakness of the interactions is such that it isn't possible to detect individual photons interacting with individual gravitons. In any case, however, the interaction is known since Reissner and Nordstrom and can be found in all textbooks. It is also relevant for describing perturbations in the early universe.
While ``graviton shot noise'' may not be observable, that gravitational waves can be described as coherent superpositions of spin-2 excitations is a well-known property of general relativity and the agreement between the calculation of the variation of the period of binary pulsars with time, and its measurement-that resulted in the award of the Nobel Prize in Physics to Hulse and Taylor isn't possible otherwise.
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Some time ago I saw a program where Lee Smolin talked about how Einstein was originally interested, at least some what, with Kaluza-Klein theory. But, after some time he became disinterested in Kaluza-Klein and other extra spatial dimension theories. Smolin claimed Einstein thought about the possibility of extra spatial dimensions, but rejected it on some fundamental principles/insights. I've tried, so far unsuccessfully, to find Einstein's article/text to which Smolin referrers. Does anyone know Einstein's reasoning/insight against extra spatial dimensions? Or, perhaps, the article that Smolin refers to?
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I don't know to what paper or text Smolin was referring, but Einstein's thoughts on Kaluza-Klein are discussed in some detail in Pais's scientific biography of Einstein.
At first, Einstein sought singularity-free, empty space solutions of the 5-dimensional theory. I.e., he was hoping that Kaluza-Klein might produce a solution that corresponds to an electron in our four dimensional spacetime. Together with Grommer (Scripta Jerusalem Univ. 1, No. 7, 1923) he showed that no such centrally symmetric singularity-free solutions exist. In 1926, in a letter to Ehrenfest, he expressed his misgivings that Kaluza's theory is "too unnatural". But then, in 1927, writing to Lorentz, he stated that unification was "achieved in a completely satisfactory way in by the five-dimensional theory".
In 1931, with Mayer (PAW, 1931, p. 541), he presented a new formalism in which the fifth dimension was no longer an "extension of the physical continuum". However, in this formalism it was necessary to assume that Fkl is the curl of a 4-vector, and the field equations were not derivable from an action principle. This approach was abandoned after 1932.
Later, in 1938, Einstein once again considered a five-dimensional theory. This time around, his hope was that the quantum nature of our four-dimensional world would arise from a classical five-dimensional field theory. (Einstein and Bergmann, Ann. Math. 39, 683, 1938; Einstein, Bargmann, and Bergmann, T. von Kármán Anniversary Volume, p. 212, CalTech 1941.)
When this ho