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Black Holes - Science topic
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Questions related to Black Holes
I just watched the Leonard Susskind lecture at Berkeley,
and I wish somebody could answer me a question.
Do entangled Black holes exist in the real world?
Because it seems to me that it's pretty hard for particles (lots of them) to first become entangled and then go on to separately form 2 distinct Black holes.
And I also guess that not all the particles that comprise the two Black holes would have been entangled prior to the Black holes formation. How does that affect the entanglement of the Black holes? Let's say that only 10% of the particles that formed the 2 Black holes were entangled at their formation. Will the Black holes still be entangled. And will they be fully or partially entangled?
Mathematically, it is posited that the cosmic or local black hole singularity must someday become of infinite density and zero size. But this is unimaginable. If an infinite-density stuff should exist, it should already have existed.
Hence, in my opinion, this kind of mathematical necessities are to be the limiting cases of physics. IS THIS NOT THE STARTING POINT TO DETERMINE WHERE MATHEMATICS AND PHYSICAL SCIENCE MUST PART WAYS?
In the gravitational collapsing phenomenon, if density and Kretschmann curvature scalar diverges uniformly at t-> infinity.
Is it a singularity?
if yes, then what is the nature of singularity -Black hole, Naked or eternally collapse?
Are there any other theories similar to Participatory Universe or SuperDeterministic Universe?
It is known to all that the propagation of gravitational field is not instant.
So for black holes, the gravitational field generated by the singularity of the black holes needs time to travel before exerting gravitational pulling forces on other celestial bodies.
According to gravitational time dilation, the time near black holes are extremely dilated to infinity.
This indicates, given the limited age of the universe, the gravitational field generated by the singularity of any black holes have NOT exert any pulling forces on any celestial bodies yet.
Thus, we can conclude, it is impossible for any current celestial body to be pulled by the gravity of any black hole and orbit around a black hole. actually there should be no celestial bodies now gravitationally pulled by any black holes at all.
But, this conclusion is apparently absurd.
Any professor can explain this please?
DARK MATTER AND DARK ENERGY
Dark Matter cannot be detected by any device invented till the date.
Dark matter is so light and spread over the universe indefinitely.
Dark Energy is much more faster than light.
Dark energy is also cannot be detected by any devices.
Dark Energy is Transparent to all other matter.
Dark Matter and dark energy emitted simultaneously when a matter converted to any type of detectable energy. This may cause the quantum tunnelling, a chance transporting detectable particle with dark energy.
- Atoms do not have empty space; all the empty space we consider are occupied by dark matter.
- Atoms- nuclear force controlled by dark matter present in the nucleus.
- Dark matter particles actually repel each other, But at certain condition(P/T) it may come close each other and make other normal particle to coagulate.
- In Black hole Dark matter also absorbed and helps to convert another type of new elements by fusion reaction of the matter in black hole.
- Finally, all black hole will collapse and converted to singularity.
- Then A new universe will form after another big bang, the second universe
- The new universe may consist of new elements which are not in the periodic table available now.
- The next generation universe may contain electromagnetic energy without LIGHT ENERGY.
Incoming material approaching the event horizon of a black hole when viewed from a stationary object somewhere outside the hole travels at the speed of light. At the same time, the event horizon of a black hole rotates at speeds close to the speed of light. How do these factors relate to the dynamics at the black hole's surface? What is the relationship between incoming matter and centripetal force?
I have not directly studied Hauwking's radiation, I only know what my teachers told me about it and which is constantly repeated in popular science texts.
It says: If a pair of virtual particles materializes on the black hole's event horizon, one of them may move away, while the other falls into the hole, so that the black hole emits a radiation and gradually evaporates.
I don't understand this evaporation process as in the process the black hole gains a particle, so that its mass increases instead of decreasing. Worse, the universe outside the hole is also gaining mass to the detriment of the void.
Could somebody help?
We assume this to be true and this may be the reason why the rule,
[Two 3D bodies of different shapes cannot have the same volume to area ratio unless both have the same volume and area?]
applies to half-spheres but not full spheres.
We know that the massive stars at the ends of their lives turn up to be black holes, and we know that in the center of each galaxy there's a massive or super massive black hole. Does this mean that we can say that the galaxy is a remnant of that star after it exploded?
Singularity in a center of a black hole is a wrong idea. Here is my preprint https://zenodo.org/record/7276801
After one month of intense research, I did not find one article that would give proof of astronomical observation has confirmed the singularity of a black hole.
Please help, I'm in trouble!!
Black holes do not emite light/radiation because light/radiation cannot scape from them or because light is not generated in a black hole - since the strong gravitacional field and time change compications do not permit the energy level transition of electrons/nuclear particles (energy level colapse)?
How would we go about specifying the position of our solar system in the universe, let us say
to an intelligence residing in an unknown part of the universe (assuming for simplicity that we can neglect the sun's motion in our galaxy).
Are there any objects or "landmarks" in the universe that could be used as known points of reference that could be used to specify our location to other intelligent beings residing in a distant part of the universe ? I am thinking of an exact analogue of longitude and latitude for the earth's surface.
An obvious answer would be simply to specify the aspect of the sky (and all known data) as seen from earth or the sun. But would this really be helpful, even if this did specify uniquely our position ?
Relativistic considerations further complicate matters.
I invite anyone to participate to an open discussion on the latest “findings” on Black-Holes' research. The motive of this thread is a set of articles appeared in the issue of September 2022 (p. 26-51) of Scientific American magazine under the title “Black Hole Mysteries solved”.
I have proposed a new way of thinking about Nature/Reality NCS(Natural Coordinate System) (https://www.researchgate.net/publication/324206515_Natural_Coordinate_System_A_new_way_of_seeing_Nature?channel=doi&linkId=5c0e3a7d299bf139c74dbe81&showFulltext=true) and I would ask whether you recognize any basic distinction between the above preprint(and the following Appendices) and the articles of Sci. Am.. This thread is intended to be an open– in respect to time and subject - discussion forum for the latest results of Black Hole research in order to advance new perspectives based on NCS and to put the proposals of NCS to the public assessment.
In order to seed points of arguments, I picked up some phrases from the articles of SciAm in comparison to phrases or references from NCS preprint.
- “Paradox Resolved” by G. Musser. “Space looks three-dimensional but acts as if it were two-dimensional.” (p.30) → NCS (p.11-13, 49-52).
- - “It says that one of the spacial dimensions we experience is not fundamental to nature but instead emerges from quantum dynamics” (p.31) → NCS (p.11-13).
- - “Meanwhile theorists think that what goes for black holes may go for the universe as a whole” (p.31) → NCS (p.31-38, 46-47).
- “Black Holes, Wormholes and Entanglement” by A. Almheiri- “The island itself becomes nonlocally mapped to the outside” (p.39) → NCS (p.44-47), https://www.researchgate.net/publication/345761430_APPENDIX_18_About_Black_Holes?channel=doi&linkId=5facf0fe299bf18c5b6a0d4d&showFulltext=true .
- “A Tale of Two Horizons” by E. Shaghoulian- The whole article is about BH-Horizon, Holographic Principle, Observer, and Entropy → NCS (p.31-38, 44-47, 54-61, 6-7), https://www.researchgate.net/post/What_is_Entropy_about_Could_the_concept_of_Entropy_or_the_evaluation_of_its_magnitude_lead_us_to_the_equilibrium_state_of_a_system .
- “Portrait of a Black Hole” by S. Fletcer- The article is about the history of the observation of Sagittarius A* (the BH at the center of Milky Way galaxy). There is no obvious connection with NCS.
PS. This discussion is NOT open for new “pet-theories” apart from NCS.(!!!)
There are some famous corollaries of the equivalence principle:
1. Unruh effect is locally equivalent to Hawking radiation near the horizon, therefore "static" observer outside a blackhole will see radiation, while a free-fall observer will not.
2. Firewall, i.e., a free-fall observer will be evaporated at the horizon, is forbidden by the equivalence principle.
However, there is no physical law saying that no inertial observer will see thermal radiation or Firewall (it is bizarre, but not forbidden) in flat spacetime. The problem is the equivalence principle only restricts the evolution rule of the system but has no hint on boundary conditions. When people are using the above corollaries, are they assuming some particular boundary conditions?
How can we apply the equivalence principle in general?
The uniform accelerated observer sees isotropic thermal radiation with no net energy flux.(Gerlach, Ulrich H. 1983 as an example) However, people naturally believe Hawking radiation causes blackhole evaporation, assuming non-vanishing energy flux for an outside observer. The only difference is blackholes do not have a uniform gravity field, but I cannot see why it causes anisotropic radiation.
By the way, even if there is some correction causing anisotropic radiation, can we still observe some thermal radiation moving from infinity to the blackhole, which is implied by the Unruh effect?
This finding has caused quite a stir in the physics community, as it seems to imply that information can be lost forever in a black hole. However, Hawking has since proposed a solution to this problem, known as the "information paradox." According to Hawking, the information that falls into a black hole is not actually lost, but is instead encoded on the event horizon of the black hole.
LIGO and Virgo consortium has published results in which the mass of a merged black hole is always less than the sum of masses from the binary black holes.
GR can predict this mass loss in the Bondi-Sachs Formalism, often in the range of 5% loss while the merged event horizon is not spherical.
Not everyone agrees with published mass loss. See Tables 5.2 and 5.3 for no mass loss.
References are given for mass loss.
In my publications I compare the LIGO mass loss to theory of Polarizable Vacuum extended for high speed with reasonable agreement. In other threads I asked the question if high speed might cause part of mc2 energy to convert to pc energy. It is not widely accepted, but is allowed in the popular energy momentum equations for GR situations where curvature cannot be ignored.
In Black Hole Mergers Does Part Of Mass Energy mc2 Convert To Momentum Energy pc?
We all are told that any object (even light or information) that reaches at Black Hole's (BH's) event-Horizon can not escape from inserting into the BH.
What is the velocity at the point of passing the event-horizon?
I argue that this should be equal to c (light velocity), because if it was less than c it could be pushed, under special circumstances, with a strong, but finite, force in order to get a velocity away from BH's horizon. The result would be, at list for a small period of time, to depart from it (horizon) that is, by definition, not possible. The only way this to be avoided is the object would have velocity c when passing the horizon.
One of the alleged difficulties of producing a so-called quantum gravity theory is due to the Heisenberg's uncertainty principle.
To probe ever tinier distances, we need ever greater energies. The problem is that if you concentrate too much mass/energy in a tiny space, the gravity of such a space becomes so huge that tiny black holes form, making the measurement impossible. Even though that assumes GR holds in the microscopic realm.
This is my question. How do we know that a high energy allocated to a tiny subatomic region of space would create a tiny black hole, since we don't have any proven UV-complete theory of quantum gravity to begin with?
How do scientists know that a high energy concentration in a tiny space would lead to a tiny black hole?
Here's a precise description of this issue (it starts at the very right time where professor Matt O'dowd explains the issue):
Could Vaidya space-time be regarded as the evaporation of black holes? we know that ingoing Vaidya is considered as the formation of black holes. How about the outgoing Vaidya as the evaporation?
The recent development of EHT images influenced us to study the shadow of a BH in more detail, as we can extract some information about the source. But I feel there is no strong evidence or support for determining the spin of the compact source.
Your comments are welcome.
Hello everyone,
I did some research on the internet about analogies between nonlinear optics (NLO) and general relativity (GR), e.g. https://arxiv.org/pdf/0711.4796.pdf. That's already a very nice result, but is it possible to go even futher? It's a stupid idea, but since both GR and NLO are nonlinear field theories, is there any mapping between these two say at least for special solutions to the Einstein field equations? So more generally asking: Is it possible to simulate and study black holes (or other GR scenarios) with nonlinear optical setups in a earth-based laboratory? I'm really excited about this. Thanks a lot!
Philip
We all know that accretion disks around BHs are presumably be magnetized in nature. If we consider ideal MHD, we know magnetic fields are frozen within the plasmas. Now, magnetic fields are turbulent, so can they help in raising the temperature of the disk? And is it significant?
How are calculations, the mathematics used to find astronomical objects?
Black Holes out of a galaxy: do they exist???
➣➣The question is as follow.
Are there black holes outside the confines of a galaxy{*}, in the spaces between one galaxy and another???
{*}Galaxy is not meant only the Milky Way but any type of galaxy.
In what way can be identified and/or measured these hypothetical extragalactic black holes???
➢➢Il quesito è il seguente.
Esistono buchi neri al di fuori dei confini di una galassia{*}, negli spazi tra una galassia e l'altra???
{*}Galassia non viene intesa la sola Via Lattea ma qualsiasi tipo di galassia.
in che modo possono essere individuati e/o misurati questi ipotetici buchi neri extragalattici???
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IF there are free floating black holes, then it is very likely that there could also be extra-galactic ones??
What are the implications for the total mass of the Universe??
🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻🔻
First ever free-floating black hole found roaming through interstellar space. PHYS•org.
An international team of researchers has confirmed that a possible microlensing event witnessed in 2011 was due to the presence of a free-floating black hole roaming through interstellar space—the first of its kind ever observed. The group has published a paper describing their findings on the arXiv⁂preprint server.
Scientists have assumed for some time that there are many black holes wandering around in interstellar space, but until now they had not found one. This is due to the very nature of a black hole—they are difficult to spot against the black backdrop of space. Still, the evidence for their existence was strong. Prior research has shown that black holes are often formed when stars reach the end of their lives and their cores collapse, generally producing a supernova. And because many such supernova have been observed, it seemed clear that many black holes must have been created as a result.
But finding them has meant looking for lensing effects, when light from stars is bent by the pull of the black hole. Given the great distances, the lensing effect is slight, making it nearly impossible to detect using even the best modern telescopes. But luck prevailed in 2011 when two project teams looking for such lensing spotted a star that appeared to brighten for no apparent reason. Intrigued, the researchers with this new effort began analyzing the data from Hubble. For six years, they watched as the light changed, hoping that the change was due to magnification from a black hole. Then, they found something else—the position of the star appeared to change. The researchers suggest the change could only be due to an unseen moving object exerting a force that was pulling on the light as it passed by—an interstellar black hole. The researchers continued to study the star and its light, and eventually ruled out the possibility of any light coming from the lensing and also confirmed that the magnification had a long duration, both of which are prerequisites to confirming the existence of a black hole.
Taken altogether, the evidence is strong enough to confirm the sighting of a free-floating black hole. The researchers were even able to measure its size, at seven solar masses. They also found that it is traveling at approximately 45 km/second.
⁂An Isolated Stellar-Mass Black Hole Detected Through Astrometric Microlensing. arXiv:2201.13296v1. https://arxiv.org/abs/2201.13296 ⁂ We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry of the source star of the long-duration (t_E ~ 270 days), high-magnification microlensing event MOA-2011-BLG-191/OGLE-2011-BLG-0462, in the direction of the Galactic bulge. HST imaging, conducted at eight epochs over an interval of six years, reveals a clear relativistic astrometric deflection of the background star's apparent position. Ground-based photometry shows a parallactic signature of the effect of the Earth's motion on the microlensing light curve. Combining the HST astrometry with the ground-based light curve and the derived parallax, we obtain a lens mass of 7.1 +/- 1.3 M_Sun and a distance of 1.58 +/- 0.18 kpc. We show that the lens emits no detectable light, which, along with having a mass higher than is possible for a white dwarf or neutron star, confirms its BH nature. Our analysis also provides an absolute proper motion for the BH. The proper motion is offset from the mean motion of Galactic-disk stars at similar distances by an amount corresponding to a transverse space velocity of ~45 km/s, suggesting that the BH received a modest natal 'kick' from its supernova explosion. Previous mass determinations for stellar-mass BHs have come from radial-velocity measurements of Galactic X-ray binaries, and from gravitational radiation emitted by merging BHs in binary systems in external galaxies. Our mass measurement is the first ever for an isolated stellar-mass BH using any technique.
Dear Researchers in the field :
Does anyone know what the KAGRA Gravitational Waves Observatory it's been up to ?
KAGRA announced at the end of last year (2019) that they were ready for the kick off. And that in February this year (2020) they were turn to the sky for the first (real) observations and be ready to joing the efforts of the LIGO-Virgo collaboration.
But I haven't hear anything about KAGRA since that time.
I'm sure they had to close due to the COVID-19 pandemic, probably since March.
But, now in December, almost the end of the year, I would have expected to hear news about Observatory.
Does anyone know what is it status nowadays ? Maybe the explanation is that the facilities kept shut down almost the whole year since the pandemic.
If someone know fresh news, I'll appreciate the sharing.
Best Regards all ! :)
I doubt a long day.
This is an imaginary suspicion!
Quantum Entanglement, if we understand it better and use it like a live tv through technology,
""" that means it's ( Quantum Entanglement ) transfer information fast like rather than light.
And note: near the black hole (where time goes much shorter than Earth) """
Now if I look from near the black hole, at things happening on Earth through a live camera that works with this Quantum entanglement technology/like, can I see things on Earth as fast-forwarded video of things happening on Earth? Or whatever else happens.
As well as watching "things near the black hole" from Earth that sounds like slow motion video?
Please help anyone, thank you :)
Recently, black-holes were demonstrated to exert a pressure on their adjacent surrounding space (see: https://scitechdaily.com/physicists-total-surprise-discover-black-holes-exert-a-pressure-on-their-environment/amp/"Physicists’ Total Surprise: Discover Black Holes Exert a Pressure on Their Environment – SciTechDaily")
Reference: “Quantum gravitational corrections to the entropy of a Schwarzschild black hole” by Xavier Calmet and Folkert Kuipers, 9 September 2021, Physical Review D. DOI: 10.1103/PhysRevD.104.066012
In two old preprints of mine (2018 and 2020), I've also predicted that all black-holes exert a mechanical pressure on their adjacent environment which I've defined as being actually a reaction(al) force produced by a predicted universal black-hole-associated Casimir force.
More precisely, a black-hole (bh) limits the spontaneous appearance of virtual pairs (VPs) inside it and that creates a gradient between the outer and inner VPs (a positive gradient between the number of VPs per unit of volume outside vs inside that bh), a gradient translated in a (bh-associated) Casimir force (bhaCF) exerting an additional out-to-in pressure on that bh (which bhaCF also generates a reactional force that acts from inside to outside that bh, manifesting as a pressure exerted by that bh on its adjacent surrounding space). See the two preprints cited next:
[1] “(eZEH working paper - version 1.0 - 10 pages - 2.08.2018) An extended zero-energy hypothesis: on some possible quantum implications of a zero-energy universe, including the existence of negative-energy spin-1 gravitons (as the main spacetime “creators”) and a (macrocosmic) black-hole (bh) Casimir effect (bhCE) which may explain the accelerated expansion of our universe”:
[2] “(bhCE-HR-AE-ObU - version 1.0 - 18.11.2020- 2 A4 pages without references) A proposed black-hole-associated Casimir effect (bhCE) possibly inhibiting Hawking radiation (HR) and creating a spatial expansion around any macro/micro black-hole (possibly driving the global accelerated expansion of our observable universe)”:
What do you think of my proposed black-hole-associated Casimir force and its reactional force (manifested as a pressure exerted by black-holes on their surrounding space)?
Doesn't the angular momentum of a BH indicate that it is not a singularity, but an extended object?
If angular momentum is conserved, where does the moment of the BH accretion disk go?
The answers I have found do not explain what rotates.
Saying that it is the black hole what rotates does not explain it.
I have read that Kerr metric black holes don't have point singularities, but this refers to mathematical equations, not physical reality.
Thank you.
Gibbons and various other people (including myself) claim that there is no higher force value than
c^4/4G = 3.0 * 10^43 N
and no higher power than
c^5/4G = 9.1 * 10^51 W
in any physical system in nature. Research so far has shown that boosts cannot help to exceed the limit, neither do black holes, nor quasars. In all cases explored so far, horizons, in combination with the proper dimension of the bodies involved, prevent exceeding the limits. Recent attempt to construct counter-examples, found on arxiv, have been shown to contain mistakes. The maximum power radiated from the brightest black hole mergers observed so far is about 200 times smaller than the limit. Even the highest electric or magnetic forces are much smaller. The limits also appear to be related to general relativity, so that higher values might be possible in alternative theories of gravity.
What counter-example or paradox comes to mind?
How could one try to achieve a larger force or power value?
Any suggestion is of interest. The question is interesting also for another reason: it resembles the question whether there is no higher speed that c = 3.0 * 10^8 m/s for physical systems.
HU (the Hypergeometrical Universe Theory) proposed a new model for the creation of the Universe, called The Big Pop Cosmogenesis.
Big Pop Cosmogenesis proposed that the Universe started as a Hyperspherical Metric Fluctuation, which upon partial recombination, decays into an Inner Dilation Layer and the outermost Contraction Layer.
Upon motion (at the speed of light), the Universe (Outermost Dilation) fragmented into a Blackholium (a hyperspherical hypersuperficial Black Hole). The Blackholium expanded until a phase transition into the Neutronium (neutron star density hyperspherical hypersuperficial Neutron Star).
That phase transition led to the triggering of hyperspherical harmonic acoustic oscillations. These Neutronium Acoustic Oscillations were frozen by a further reduction in density.
These frozen hyperspherical harmonic acoustic modes are what we see in the Cosmic Microwave Background.
HU uses Planck CMB observation to extract the hyperspherical harmonic acoustic modes composition.
Once one has that composition, one can calculate the density fluctuation anywhere.
The video contains the initial density fluctuation (1:100,000) that after billions of years, should create a corresponding galaxy density across ALL observable and unobservable Universe.
This means that starting from our CMB, one can create a map (based on observations of the CMB at different positions within the hyperspherical hypersuperficial Universe) that would tell you where you are anywhere where the Universe exists.
This video is less ambitious and only displays our 3D observable Universe.
I was doing pictures. It was possible to extend the numerical solution for the place that people call the Schwarzschild radius. Now you can describe how g_ {00} behaves,
- Somewhere around 50 Schwarzschild radius it graphically merges with Schwarzschild's solution.
- There are no peculiarities in the area of the Schwarzschild radius.
- The solution apparently exists everywhere, except for the origin.
- g_ {00} is strictly positive (time does not stop).
- Somewhere around 0 <r <3.4rg quickly decreases to almost zero. This is exactly close to the estimated radius of neutron stars. Time in this area almost stops.
- So far, the solution has been extended to 0.98. The value for g_ {00} is about 10 ^ (- 260).
To begin with, where is the mass of a black hole? If we are not able to define a location in spacetime for that mass, we could think just about the deformation of spacetime around the event horizon.
How does Hawking radiation reduce the energy and mass of the black hole? Talking about particle pairs, does the negative energy particles annihilate with the particles inside the event horizon and if so, could that interaction which occurs inside the event horizon affect the event horizon radius?
As we know that planck's constant is universal constant so some Theoretical aspect shows the existence of particle having mass of Planck mass and dimensions having planck's length
So if you know something or any idea please feel free to express it will help me
If a black hole swallows an object of mass "m" and the initial mass of the black hole being "M", then does the total mass of black hole be = M + m?
Will the Schwarzschild radius change accordingly?
The paper describes the insides - the basic concepts of the Math Microscope, demonstrates the results of Super-Resolution images obtained from the Event Horizon Telescope and analyzes the results of the movement of clusters of stars that go around the Black Hole. The presence of point objects - single stars in the SR image allowed us to implement a new breakthrough approach in the problem of SR images of Powehi Black Hole in the concept of MM. In the paper, we reviewed and illustrated new concepts: Invertability Indicators and Adequacy Characteristics of discrete Models of Apparatus Functions. With these new concepts, in the inverse problem, for the first time, we were able to answer simple questions: What are we dealing with? Moreover, have we solved the inverse problem? The paper demonstrates the “manual solution” of the problem of Reconstruction of AFs and Super-Resolution on MM. In the Discussion at the end of the paper, we pose the problem of creating two Artificial Intelligences for the automated solution of the R&SR problem with the interpretation of the SR results of BH images from EHT.
Does anyone know the answer to this question: Can Black holes be a recycling process of old stellar material to produce a new one?
Due to the Unruh effect the vacuum energy for the uniformly accelerated observer looks like as the equilibrium background with the Hawking-Unruh temperature $T=\hbar a/2\pi ck_B$, where $a$ is the acceleration. So we can conclude that the vacuum energy specifies a noninertial frame of reference with respect to which one can define an acceleration of any particle (note that vacuum energy does not specify any inertial frame of reference because it is uniformly distributed in a four-dimensional continuum so that all four directions for it are identical). But as it follow from Freedmann's equations a relative acceleration of two galaxies (observers) which currently are on distance R from each other is equal to $a= (\Omega_{\Lambda}-\Omega_m)H_0^2R/2$. So if in some point of the Universe the Hawking-Unruh temperature is equal to zero for the other points it is not so. Such way the vacuum energy specifies on an existence of a center of the Universe contrary to the cosmological principle which claims that the properties of the Universe are the same for all observers. In this situation it does not matter whether we can observe the Unruh radiation or not. This means that our knowledge about the Universe and the vacuum energy are incompatible.
To solve this conflict one can assume that the Universe is a hypersphere which isotropically expands on the background of 4D Euclidean space. In such case the accelerations (with respect to background) of all points belonging to hypersphere would be equal. As an alternative, we also can assume that vacuum energy does not exist in reality. Unfortunately both of these assumptions lie beyond the standard model of physics. Can someone help me solve this puzzle?
Is gravitational waves really exist ? This is a humble declaration of Einstein that GTR is a wrong theory, then why should we blame him. It is human nature every one wants show that they are intelligent and make the best effort to impress the scientific community and the society. The same thing he also did. It is a survival tactics but when they have reached the goal usually they try to correct their wrong by some way or other to remove their guilt. So it is high time that we should forgive Einstein by declaring that his theory was wrong and that there is no gravitational waves by agreeing with his later results. We should council (both Scientifically and Psychologically ) the people who detected the gravitational waves, that they are merely weak radio waves. All students from the school level itself, should be asked to take oath that they should fall into this black hole since we need give Einstein's soul a rest.
Most people would answer this question ad hoc: What a redundant question, of course a negative energy density cannot exist. But all these “ad hoc “-people oversee that the gravitational field around a mass indeed has a negative energy density. The next ad hoc remark is then, what is the sense of this question if the negative energy density of gravitational fields is fact.
After this remark we get closer to the point. The only possibility to avoid a negative energy density around a mass is the existence of a gravitational field with positive energy density, which overlays all gravitational fields around masses.
The existence of such a gravitational field, omnipresent, with a positive energy density, and nearly homogenous in the whole universe, now has consequences, which we consider with the following points.
(1) The existence of such a field requires a closed finite universe. A positive energy density cannot fill an infinite volume.
(2) A gravitational field with a positive energy density X allows the propagation of gravitational waves with a wave pressure p and an energy density E with p=√(EX). This is a result of wave theory.
(3) Every grain of mass, including atomic nuclei, electrons, and photons moves a small dent through the homogenous background field with energy density X. This movement leads to post pulse oscillations. “Generation of post pulse oscillations” is a wave excitation mechanism completely different from “quadrupole radiation”, which currently is proposed as mechanism for gravitational wave generation.
(4) The post pulse mechanism is much more efficient. It leads to the general effect that any mechanic or electrodynamic activity generates gravitational waves. This means that X in a closed universe, is continuously growing.
(5) X as a medium, which supports wave propagation has a density, a wave pressure component, and a kinetic component. The pressure and the kinetic component are the result of wave excitation.
(6) What is the current amount of X? This amount is presumably above the range of the gravitational field around a neutron star. The Tolman-Oppenheimer-Volkoff-limit determines the value.
(7) Black holes slightly exceed this limit. But they cannot really exceed it because there remains nothing to be exceeded.
(8) Black holes become clouds of matter in a strange condition surrounded by a zone of zero gravity.
(9) The zone of zero gravity shields the cloud of matter from the oscillating background field with energy density X.
(10) The field X penetrates all kinds of matter except the extremely dense matter inside black holes. The energetic interaction of field X with normal matter including neutron star matter is a small one-way street towards X. But the matter inside a black hole is in a much denser state, susceptible for excited matter X with a pressure- and a kinetic component.
(11) The excitation of field X with gravitational waves shrinks the zone without gravitation around black hole matter. If the field X reaches the matter, the port of energy flow from X to the black hole matter is open.
(12) The consequence is that after a few million years the black hole matter becomes transformed into a widespread cloud of atomic hydrogen which provides new star fuel for the next life cycle of the universe.
If nature does not allow a negative energy density, the points (1) to (5) above are mandatory consequences. The points (6) to (12) are speculations about the amount of the gravitational energy density which surrounds us. However, the most remarkable point is that the “nonexistence of negative energy density” leads to a new model of the universe, fundamentally different to the big bang theory.
Hello,
If LIGO can detect stellar to supermassive blackholes why is it difficult to detect intermediate black holes?
It appears it has only ever detected one so far: (https://www.google.com.au/amp/s/www.space.com/amp/black-hole-intermediate-size-ligo-gravitational-waves-discovery.html intermediate-size-ligo-gravitational-waves-discovery.html)
Initially I thought it was because LIGO was incapable of detecting intermediate black holes but it seems the reason is to do with black holes and not LIGO?
Im not a space scientist just curious!
for an external observer the negative energy of the virtual particle may have positive energy relative to an observer inside the horizon. So, the energy sign (-) is frame dependent. How can I see that clearly ?
I know that for understanding this situation, we must note that the Hamiltonian is the generator of time translations. But I need more explanations.
thanks.
N.M
We know gravitational field distorts time and space as well as the path of the light wave. Due to this distortion, some space objects may be hidden from our observations. Is it possible even if the objects don't have high mass density like a black hole say a solar system size star system to be invisible due to the gravitational fields of other nearby objects?
Many conservation laws are found in references, also selection rules and exclusion rules. Time passage is taken for granted, but I don't find any law that compels time to pass.
Discussions in other threads explored that possibility that passage of time is started by creating particle pairs with mass out of a swarm of photons. Mass experiences the passage of time while photons do not.
Consider an end of time. In theory all the mass would convert to photons including black holes. Entropy the arrow of time would go to zero. Distances could not be measured, and might not continue to exist. This begins to sound much like descriptions of our early universe many researchers have given, which is the reason for this question.
Roger Penrose in the book Cycles of Time and in many speeches has a dilemma that enormous length of time is required for black holes to evaporate in the manner of Stephen Hawking. A remedy might be found in some other mechanism for time to stop passing sooner.
Comparing other laws, it seems likely that time should continue to pass unless something causal occurs or a permissive is lost in physical cosmos.
In other threads topics were explored about possible ways time might stop by natural processes, and other possibilities that human activities working with extreme high energy densities might cause time to stop locally in a bubble of quantum modified space.
Researchers debate what might happen to a modified bubble, and how large it would need to be before it could begin to expand uncontrollably to fill the cosmos. Also they make theories about how a bubble might be stopped. A few researchers look to such bubbles as a source of dark energy.
The question is asking if researchers have other information or theories about passage of time.
Does Any Law Of Science Require Time To Continue Passing?
You can see in this picture. That the magnetic effect of a black hole reflects the rotating optical magnetic force. And we can name the magnetic effect, the optical magnet effect.
We did not identify the black hole in full detail yet. Does it has an event horizon or apparent horizon. We are trying to modify our theory to resolve the problem of singularity. Is the black hole without singularity still be a black hole? What is the main character of the black hole, the singularity or the event horizon.
How can we establish the age of a black hole? I think that black holes are the oldest and the most massive objects in the Universe. Am I right? Since nothing gets out from a black hole we cannot know the age of the matter inside it. Am I right?
If it is true that they are the oldest objects in the universe, knowing their age may give us information about the age of the universe, and, MAYBE, about when the Big Bang occurred. For instance, the Big Bang couldn't have occurred after the black holes were formed. Also, it may be that a black hole is a shard from the the object that exploded and produced the Big Bang.
I appologize, ny question may seem naive, cosmology is not my domain of competence.
My question is this:
One of the most extraordinary predictions of general relativity is the prediction of the singularities of black holes, where this theory stops making sense. For example, there are the classical solutions to the Einstein equations, such as the Schwarzschild, Kerr, Reissner-Nordström, and Kerr-Newman solution; and, even more, the Penrose works. But general relativity predicts them by going beyond general relativity, since at the point of singularity itself, physics and even mathematics itself lose their meaning (not to mention philosophical-conceptual aspects, such as a mass and/or electric charge concentrated at a dimensionless point).
Well, as we know, general relativity is built on the mathematical foundation of differential geometry, with a manifold that must be C ^ n differentiable.
Or is it that we can perhaps consider general relativity as a limit case of a more general theory that can explain the paradox of the singular point and where we can to accept a hypothesis of that explanation coincides with the infinite mathematical limit to which the theory of general relativity tends in said singularity? Or perhaps in this possible more general theory the limit of gravitational collapse is not allowed due to the existence of a minimum spatial scale?, for example, string theory or theories of discrete space-times, with a minimum spatial length, which it could be the length of Plank.
I hope you can clarify this question for me.
Thanks.
As we know that the Law of Newton's Gravitation, gravitational force depends on the masses of interacting particles but not on their energies. And we also know photons are massless, chargeless, energy pockets.
So, there are only two possibilities. The 1st possibility is "Photons do possess trivial masses and the theory about them saying they are massless would be invalid" or the 2nd possibility is "energy can also be influenced by gravity and the law should be reformulated".
Einstein's theory of relativity is now accepted by the scientific community. In 2020, Penrose was awarded one half of the Nobel Prize in Physics for the discovery that black hole formation is a robust prediction of the general theory of relativity.
The total energy of two bodies in gravitational interaction must be
(m1 + m2) c^2 - G m1 m2 / r ,
where r is the distance between them. When r is G/c^2 times the reduced mass, the total energy and hence the total mass vanish! It is the Schwarzschild radius, so a black hole may form. Does it necessarily have zero mass? Is this not contradictory?
If quantum information is stored on the Event horizon of the black hole (according to the Holographic principle), What happens to information when black holes evaporate or merge?
The black hole is a thermal system as defined by the Hawking radiation hypothesis. The black hole emits radiation at a very low temperature. I would like to know how one defines its thermal conductivity?
According to Einstein-Rosen bridge theory, shortcuts in space time where if galaxies or multiverses come close to each other, due to excess increase in electro magnetic waving some fructures like holes or tubes, not to be confused with Black holes, form as shortcut tunnels in space time where the observer can see the destination he will be arriving if he goes into the hole when he looks into the worm hole. Having strength as a theory, somehow the worm holes must be detectable, but they are not. What do Physicists think? Are worm holes detectable?
According to general relativity, it is well known, and notably confirmed by Penrose and Dirac, that in the broader reference frame of the universe---that is, the reference frame astronomers use to describe their observations---a black hole would take forever to form through gravitational collapse. Yet many astrophysicists assume without qualification that supermassive black holes exist at the centers of galaxies and can be indirectly detected at the present time.
Are these theorists contradicting general relativity? Or do they assume such black holes are primordial, or were formed through unlikely non-gravitational processes? Unless primordial, it seems more consistent to assume supermassive quark or neutron stars reside at the cores of galaxies.
How does one combine the basis of Quantum Physics that the information cannot be destroyed with the GR statement that black holes destroy the info?
If the magnetic direction of any two black holes is made equal. So the capacity of attraction decreases to zero? If it becomes zero. So we can make the ability to magnetize / attract other black holes to zero or similar by using such an artificial black hole.
(french version is available on my research profil)
In my last article "The stress energy in fluid mechanics", I explain what is current researches about fluid space-time.
On the one hand, Franck Delplace thinks that this viscosity is high. However, I do not find that coherent at all, in the sense that if a high viscosity existed, the bodies that move in space-time would be slowed by this viscosity. It would be more generally a Newtonian fluid (ie a non-turbulent fluid with a viscosity), and more precisely, a Newtonian superfluid (a non-turbulent fluid with a viscosity almost zero).
I am not an astrophysicist, but that can explain the phenomenon described by Stephano Liberatti and Luca Macione: "they thought that high energy photons that travel a great distance lose a large fraction of their energy". This loss of energy, tiny, is due to this very low viscosity, which has an influence on the movement of the bodies.
In the case of high gravity (as at the beginning of a black hole) space-time bends so much that the photons are "swallowed" in the black hole. In a certain way, space-time, which is globally a Newtonian superfluid, becomes a non-Newtonian superfluid (a turbulent fluid with a near-zero viscosity). A team of physicists then noticed that the lower the viscosity, the more the fluid is turbulent. This is observed at the beginning of a black hole, which is also easily comparable to the great entropy that has black holes.
In conclusion, I think that space-time must be superfluid. If he had a high viscosity, it would risk complicating the theoretical calculations and would require reviewing all the physics, which is not necessary at all. Space-time is a Newtonian superfluid, which becomes non-Newtonian when the gravitational force becomes very large (black hole, neutron star etc ...).
6 October 2020
The Royal Swedish Academy of Sciences has awarded the Nobel Prize in Physics 2020,
with one half to
Roger Penrose
University of Oxford, UK
“for the discovery that black hole formation is a robust prediction of the general theory of relativity”
and the other half jointly to
Reinhard Genzel
Max Planck Institute for Extraterrestrial Physics, Garching, Germany and University of California, Berkeley, USA
and
Andrea Ghez
University of California, Los Angeles, USA
“for the discovery of a supermassive compact object at the centre of our galaxy”
Black holes and the Milky Way’s darkest secret
Three Laureates share this year’s Nobel Prize in Physics for their discoveries about one of the most exotic phenomena in the universe, the black hole. Roger Penrose showed that the general theory of relativity leads to the formation of black holes. Reinhard Genzel and Andrea Ghez discovered that an invisible and extremely heavy object governs the orbits of stars at the centre of our galaxy. A supermassive black hole is the only currently known explanation.
Roger Penrose used ingenious mathematical methods in his proof that black holes are a direct consequence of Albert Einstein’s general theory of relativity. Einstein did not himself believe that black holes really exist, these super-heavyweight monsters that capture everything that enters them. Nothing can escape, not even light.
In January 1965, ten years after Einstein’s death, Roger Penrose proved that black holes really can form and described them in detail; at their heart, black holes hide a singularity in which all the known laws of nature cease. His groundbreaking article is still regarded as the most important contribution to the general theory of relativity since Einstein.
Reinhard Genzel and Andrea Ghez each lead a group of astronomers that, since the early 1990s, has focused on a region called Sagittarius A* at the centre of our galaxy. The orbits of the brightest stars closest to the middle of the Milky Way have been mapped with increasing precision. The measurements of these two groups agree, with both finding an extremely heavy, invisible object that pulls on the jumble of stars, causing them to rush around at dizzying speeds. Around four million solar masses are packed together in a region no larger than our solar system.
Using the world’s largest telescopes, Genzel and Ghez developed methods to see through the huge clouds of interstellar gas and dust to the centre of the Milky Way. Stretching the limits of technology, they refined new techniques to compensate for distortions caused by the Earth’s atmosphere, building unique instruments and committing themselves to long-term research. Their pioneering work has given us the most convincing evidence yet of a supermassive black hole at the centre of the Milky Way.
CONGRATS to these great, blessed and lucky scientists
Why is nobody talking about Stephen Crothers mathematical refutation of the existence of Black Hole from his study of general relativity? He has been very vocal giving presentation at a conference.
What capacity can there be. When a black hole attracts a planet or other to itself. There may be a speed.
If the Earth going through space would be close to a black hole, it would be gone to the center of it. Perhaps it is surrounded by low-density air
My questions are:
1. Could exist a black hole there without eating Earth surrounded perhaps by vacuum?
2. If it is possible that the black hole generates a lot of energy in the out border of the event horizon that could explain that the Earth heating is about twice the received sun power?
3. If it could explain the Earth magnetic field
4. It's mass
5. How to detect it
6. If it is true, perhaps earth temperature is higher than several million years before. It is known what was the Earth temperature then?
I make these questions because I am worried about the danger of generating a stable black hole in a scientific test. If one of them were created, it would go to the center of the Earth eating earth generating a thin tunnel.
It is a known fact that nothing can get out of the event horizon of any black hole. If we say that gravitons mediate the gravitational force, then it should mean that gravitons that start from the singularity interact with objects outside to give rise to gravitational force. But from the very principle of black holes, gravitons should not be allowed to escape out of the event horizon. The case of a black hole should have been like that of the strong force, the gravitational force should have confined itself and no gravitational effects should have been observed due to a black hole. Why is this not the case?
Congratulation to 2020 Physics Laureates (Roger Penrose, Reinhard Genzel, and Andrea Ghez for their discoveries about black holes).
Penrose, Genzel, and Ghez explained to the world the black holes which are a direct consequence of Einstein’s general theory of relativity. The black holes, in which all the known laws of nature cease, are still not completely understood (at least to me). Why can't light and even time escape from black holes? How are the black holes connected to the creation of galaxies?
I am looking for the thermodynamics of the cosmological black hole in scalar-tensor-vector gravity theories. I know how should I write and find the thermodynamical quantities and equations for such a black hole, but I do not know that can I use the Bekenstein-Hawking area law or in this framework, I should find a modified version of it. I looked for it in literature and found out that some authors have said that in this framework, we should find a modified version of this law, and an author has said that we should use the ordinary form of the law.
So, what should I do?
Ultraluminous X-ray sources, because their luminosities, seem to be greater than the Eddington limit for a stellar-mass black hole. Although a few of these sources could be black holes of intermediate masses of hundreds to thousands of solar masses, it is believed that the large majority are stellar-mass black hole binaries. Micro blazars are the objects that have high luminosity because the jets lie in the line of sight. Could we therefore propose that these ULXs are actually micro blazars?
Review of black hole description