Astronomy & Astrophysics

Astronomy & Astrophysics

  • Prasanna Subramanian added an answer:
    11
    Does CME affect the pulse of the heart?
    CME can leads to blackout on Earth due to disturbance in Earth's magnetic field.
    Prasanna Subramanian

    Hi,

    The energitic associated activity of CMEs are Radio bursts, Proton emission, solar X-ray flares.  CMEs are filtered by Earth's atmosphere after L1 point.  While metric radio bursts (> 20 MHz), solar energitic proton emission  (>100 Mev) can reach Earth station and can surely affect human.  High freqency waves in a cell phone (in shirt pocket near heart) generally affects human glands, heart and brain. Totally Nine number of  Human glands are enzime generators.  Their function really affect due to any kind radiation/ or by radio waves.  The SEP emission and Type II, IV metric radio bursts can destroy power systems in the Earth and satellites in space.  Definitely they affect human and other living organism.  

  • Paul Cefola added an answer:
    4
    What is the difference between single and double averaged disturbing functions?

    Can someone please explain briefly the difference between single and double averaged disturbing functions in celestial mechanics?

    What are the physical arguments depending on which one should use single or double averaged disturbing functions? In other words, when is it legitimate to double/single average ? 

    Thanks.

    Paul Cefola

    Problems such as the perturbations of an orbit by the lunar-solar point masses lead to discussion of single-averaging and double averaging.  Single averaging is when you just average over the satellite's orbit.  The third body is assumed fix over the orbit.  In double averaging you averaging over satellite orbit and the third body's orbit.  There is a concept called Weak Time Dependence (WTD) which is relevant for some longer period orbits.

  • George Dishman added an answer:
    68
    How could CMB w/ black body spectrum have formed if: an initial singularity and stellar formation was prior to cosmic inflation?

    Cosmic Microwave Background Radiation (CMB). (question  edit  Jan 14, 2016)

    Assume stars formed prior to an inflation epoch as hypothesized in The Pearlman SPIRAL cosmological redshift hypothesis (Prior to that the stars being so dense, their light might not have been able to escape).

    Could the cause of the CMB be from:
    Prior to the stellar formation?
    During stellar formation?
    Post stellar formation?

    How do we know the initial temp of the cause of the CMB or could that temp be a variable that depends on what our current model of the universe is?


    Assume cosmological redshift does not mean the universe is expanding, as explained by The Pearlman SPIRAL.
    So consider as viable alternatives:
    a somewhat stable universe,
    a Earth / Sun Ecliptic centric, universe,
    a young universe .

    Thank you in advance for any and all proposed solutions you can think of. r

    George Dishman

    Hi Roger,

    Yes, there is a big difference between the standard concept, commonly known as the Concordance Model (because it uses the best fit parameters and is therefore "in accordance" with the observations), and your vision of what it says. There is a section on the first page of your notes that should give you a clue to this:

    "This occurred roughly 400,000 years after the Big Bang when the universe was about one eleven hundredth its present size."

    The number used in the Concordance Model is 1090 so if the CMB was emitted from material that was then 13.8 GLy away, that material would now be 1090 times farther or 15042 GLy from us. Those are wrong, the correct values are that it was 0.0416 GLY from us then and is 45.4 GLy from us now.

    Your mistake is treating the distance as if it hadn't changed between then and now even though your notes recognise that it does change in standard cosmology.

    I've added a link to a simple calculator, you can type in the 'z' value for the redshift of any source and it will tell you lots of interesting stuff about both then and now. If you have any questions about what the Concordance model says, that's an easy way to check. The default value is 1089 which is the CMB (one less than the ratio of expansion).

  • Huni Kh.Niakian added an answer:
    9
    What is meant by a “stiff” or “soft” equation of state in case of neutron star?

    In the degenerate interiors of neutron stars, the equation of state is usually just density (and composition) dependent. You can express the pressure as a polytropic law of the form P∝ρα, where ρ is the density.

    A stiff (or hard) equation of state is one where the pressure increases a lot for a given increase in density. Such a material would be harder to compress and offers more support against gravity. Conversely, a soft equation of state produces a smaller increase of pressure for a change in density and is easy to compress.

    If we using the Lagrangian density of the nucleon-meson many body system. Solve the equation of state and corresponding using different parameters like FSUGOLD,NL3,NL3*.....etc. I know every parameters have a different symmetry energy and compressibility.  But, what is physics behind the stiff or soft equation of state?

    Huni Kh.Niakian

    Hi George, framework is Fermi Gas model.

  • Thierry De Mees added an answer:
    99+
    An old question that is still fresh: Is gravity a Newtonian force or Einstein space-time curvature?
    No gravitational wave was measured yet, no graviton was detected accordingly. On the other hand no space- time curvature was observable. There is no successful experiment to validate the current theories. What is the nature of the mysterious gravity? What is the velocity of this effect ?
    Thierry De Mees

    David and Matts: Of course there exist crackpots! In the pub, you'll hear it every day.

    However, most of the mainstream scientists only rely on mainstream physics without thinking nor questioning. The advantage is that they don't need brains, they just need to check if it is mainstream or not. Moreover, they will not be excommuniated, and their wages will remain untouched.

    But in fact, in order to evaluate someone's theory, one needs brains and an unbiased mind. Where can we still find that? Nowhere any more? Who is so stupid to start thinking! Let's endlessly continue patching the shaky mainstream theories!

  • Guido Colasurdo added an answer:
    3
    Celestial MEchanics: What is the link between excess velocity vector and peri center distance, resp. turning angle?

    I am looking for a formulation between the _vector_ of the hyperbolic excess velocity and the corresponding hyperbolic orbit, especially the turning angle and the pericenter distance vector.

    I would like to model a gravity assist maneuver but how do I derive the turning of the spacecraft vecolicty vector correctly without knowing the pericenter distance. The incoming hyperbolic excess velocity vector is given, but without a corresponding position vector I cannot derive an orbit. But per definition the position is at infinity. I would appreciate any help!

    I am aware that there are a number of equations to derive the scalar relations of this parameters, but is not the vector, i.e. the direction of the incoming excess velocity already setting these parameters as well? I do not assume that the pericenter of such a trajectory is independent of the direction, right?

    Thanks in advance!

    Guido Colasurdo

    In my opinion the position of the asymptote does not matter; only direction is important; you can imagine that distance B of asymptote from body center is a free control that you use to obtain desired turning angle. (distance B is negligible compared to interplanetary distances)

    + 1 more attachment

  • Dimis Poulos added an answer:
    11
    What is the best model to predict Solar Cycle 25??

    Prediction of Solar cycle 24 based on various models that is a less active cycle is well known. What is the best model or way to predict Solar cycle 25?

    Dimis Poulos

    ...though they make wrong assumptions on the connection of the barycenter movement to solar activity I think

  • Roger M. Pearlman CTA added an answer:
    40
    What is the astrophysical nature of the observed cosmological redshift?
    In recent astrophysical literature there are splashs of acute discussions on the interpretation of the observed cosmological redshift: is it space expansion, the Doppler effect of receeding galaxies or the gravitational effect of cosmologically distributed matter. The question is how to distinctly observe these different interpretations of observed properties of cosmological redshift.
    The problem was formulated by H.Bondi (1947) and also by E. Harrison in his book “Cosmology”, Cambridge Univ. Press, 1981 (second ed. 2000). Now there are more than ten papers which argue the different possibilities. Abramowicz et al.(2007; 2008) demonstrate that only space expansion can be used for understanding the cosmological redshift within general relativity, while Chodorowski (2007; 2011), Bunn & Hogg (2009), Melia (2012) insists on the interpretation as the sum of the Doppler effect plus the gravitational effect.
    In general relativity space / space-time itself has the same level of existence as matter (Einstein equation joins them) so the space can be curved, stretch, spread (as gravitational waves) and so on. And this also can be considered as an argument in favor of the expanding space interpretation, though the problem is still open.
    Roger M. Pearlman CTA

    To all it may concern,
    The Pearlman SPIRAL an alternative cosmological redshift hypothesis and cosmology model is now published under the title 
    'Distant Starlight and the Age, Formation and Structure of the Universe'

  • Sheng Liu added an answer:
    1
    Suppose the object belongs to high-soft regime as well as mechanically powerful (cavities, shock) and also has bright nucleus what does it indicate?

    Suppose the object belongs to high-soft regime as well as mechanically powerful (cavities, shock) and also has bright nucleus what does it indicate?

    Sheng Liu

    Please read the paper, may be helpful for you.  A new approach to the correction of

    Galilean transformation.

  • Orlando Tapia added an answer:
    5
    What kind of quantum statistic should be used in the calculation of thermal rate constant at ultralow temperatures?

    The thermal rate coefficient can be obtained from the reactive cross section (σ(Ecoll)):

    k(T) = c(T)×∫P(T,Ecoll)Ecollσ(Ecoll)dEcoll

    where Ecoll is the relative collision energy and c(T) is a constants at a given temperature and P(T,Ecoll) is the statistical weight.

    In normal case Boltzmann statistic is used for the calculation of statistical weights. But Boltzmann statistic is valid when the temperature is high and the particles are distinguishable. At ultralow temperatures (T< 10K) we should use the appropriate quantum statistic (Fermi or Bose).

    What kind of quantum statistic should be used in the collision of a
    radical[spin = 1/2] + closed shell molecule (spin=0)
    at ultralow temperatures?
    What is the form of P(T,Ecoll) in this case?

    Orlando Tapia

    A comment to the question:

    What kind of quantum statistic should be used in the calculation of thermal rate constant at ultralow temperatures?
    The thermal rate coefficient can be obtained from the reactive cross section (σ(Ecoll)):
    k(T) = c(T)×∫ P(T,Ecoll)Ecollσ(Ecoll)dEcoll

    where Ecoll is the relative collision energy and c(T) is a constants at a given temperature and P(T,Ecoll) is the statistical weight.
    In normal case Boltzmann statistic is used for the calculation of statistical weights. But Boltzmann statistic is valid when the temperature is high and the particles are distinguishable. At ultralow temperatures (T< 10K) we should use the appropriate quantum statistic (Fermi or Bose).
    What kind of quantum statistic should be used in the collision of a
    radical[spin = 1/2] + closed shell molecule (spin=0)
    at ultralow temperatures?
    What is the form of P(T,Ecoll) in this case?

    End-of-question

    Dear Péter Szabó , you have gotten a couple of important answers. My comments are as follows:

    1.     What do you mean by reactive cross section ?

    2.     What do you mean by ultralow temperature ?

    You keep talking of particles that, from the context, seem to be classical systems with spin, one S=1/2 the other S=0. But a chemical reaction is better seen as a change of quantum state.

    But then, there is need to define the spectrum of this systems as well as the composite.

    I hope you understand that a ill-posed problem has no solution. Using the answers given to you, try to put the ideas of yours in shape.

    The question implies quantum scattering. And take this as a possible answer.

  • Refilwe Kgoadi added an answer:
    6
    What is the best technique to search for variability in stars?

    How would one confirm that star varies

    Refilwe Kgoadi

    Thank you for all the answers they may been very useful 

  • Robert L. Oldershaw added an answer:
    49
    Why is dark matter research so biased?

    It is scientifically desirable to include stellar scale dark matter candidates, such as stellar-mass and planetary-mass ultracompact objects, in discussions of the quest for the identity of the enigmatic dark matter comprising the overwhelming majority of matter in the cosmos.

    After 40 years of failed attempts to find the ad hoc "WIMPs", or any other form of subatomic dark matter particles, maybe it is time to completely reassess what the dark matter might be.

    Mike Hawkins has offered a cogent empirically-supported case for stellar-mass and planetary-mass ultracompacts (with primordial black holes being the most likely candidates) as the mystery objects causing microlensing events seen in bulge, halo and QSO research. [papers available for free: http://arxiv.org/abs/1106.3875 and  http://arxiv.org/abs/1503.01935 ].

    A huge population of primordial black holes satisfies the non-baryonic constraint, might also explain where cosmic rays primarily come from, and might explain why the ARCADE-2 experiment found a unexplained factor-of-6 excess in cosmological radio emission. Primordial black holes also might constitute the sources of the approximately 6,000/day Fast Radio Bursts that have been discovered/inferred in the last few years by several astrophysical research groups (Science News, Aug. 9, 2014 issue; many papers subsequently posted to arxiv.org). 
    It is a scientific error to assume, as most theoretical physicists do, that the dark matter absolutely must be composed of hypothetical subatomic particles. A scientist maintains an open mind, in word and deed. Moreover, a scientist does not condone denial of important and confirmed empirical results.
    Not long ago microlensing research (MOA group) identified at least 0.1 trillion unbound planetary-mass objects in unknown physical states (Suni et al, Nature, May, 2011).
    Astrophysicists have discovered an estimated 70 billion brown dwarf objects in the thin disk of the Galaxy. Since the thin disk represents a very small fraction of the Galaxy's volume, one can be reasonably sure that 70,000,000,000 is a lower limit.
    So let's see: trillions of unbound planetary-mass nomads and >70 billion brown dwarfs and 100s of billions of stellar-mass MACHO objects. That's a significant percentage of the total dark matter population, and it is a minimum estimate!
    Can we understand why theoretical physicists and the scientific press ignore observed stellar scale dark matter candidates, and only emphasize mythical particles like WIMPs and axions that have never been observed? It seems like a dubious and unscientific obsession.

    R.L. Oldershaw
    http://www3.amherst.edu/~rloldershaw
    Discrete Scale Relativity/Fractal Cosmology

    Robert L. Oldershaw

    My research suggests that the things at the centers of galaxies are called a black holes, but are actually the horizonless singularities interior to black holes, i.e., a ring singularities or point singularities depending on whether the BH is a Kerr-Newman/Kerr BH or non-rotating BH, respectively. This will eventually be decided empirically.

    Note also that in Discrete Scale Relativity there is a discrete conformal invariance modification to GR, and so our understanding of the detailed properties of ultracompact objects would also be modified. However, GR is not trashed - only made to operate the same way and with the same relative strength on all discrete scales of nature's infinite hierarchy.

    I would not rule out ejection of stellar scale PBH "particles" from the central ultracompact object, but again we would need strong observational evidence to back up this model.

    Best, Rob O

  • André Michaud added an answer:
    6
    How energy is transfered from photosphere to corona on the bais of elemental abundance variation from photosphere to corona ?

    As some of the research papers suggest that low FIP (below 10 KeV) elements get enhance by factor of 3-4 in Corona from Photosphere, while high FIP (above 10 KeV) elements don't show this characteristics.

    Does this effect conclude anything about energy transfer from Photospere to Corona ?

    André Michaud

    There is a quite thorough analysis of the solar corona in a textbook by Markus Anschwanden "Physics of the Solar Corona", that you may or may not have had a look at. If not, I highly recommend it.

    All elements apparently are highly if not completely ionized in the corona with temperatures averaging into the millions of degrees, with peaks reaching into the double digit millions.

    There also is an overabundance of some elements in the corona with respect to the chromosphere and photosphere that is also quite intriguing. Helium in particular seems quite noticeable.

    The sustained temp difference at the chromosphere/corona boundary, and the sustained apparent equilibrium millions+ temperatures in the corona even suggest that  some process internal to the corona could be at play.

    This equilibrium temperature is maintained despite constant exchanges with the much lower temperature chromosphere and constant outward ejections of coronal masses (CMEs)

    Quite a fascinating issue.

  • Guibert Crevecoeur added an answer:
    19
    What is the Expansion Rate of the Universe?

    Assuming that the expansion would originate from a location in deep space far from galactic influences, is there a simple mathematical formula that would describe the rate of expansion along a line from a given central point to a point on the outer edge of the sphere which theoretically would be receding from the initial point at the speed of light?

    Guibert Crevecoeur

    Dear Biswajoy,

    If "H" has two terms, one "c" constant both in time and space and the other one "b/t" only constant in space, i.e. if we have "H=c+b/t", one gets for an universe accelerating from 7 Gyrs after the Big Bang (second time derivative of a(t) positive) and with "b=2/3" (Einstein-de Sitter flat matter-dominated universe) : c ~ 21 km.s-1.Mpc-1. So the universe is indeed accelerating and the Hubble parameter is decreasing with time. One finds, e.g. : 

    • at present time t0 ~ 14 Gyrs -> H0 ~ 67.5 km.s-1.Mpc-1 (in line with Planck mission results : 67.8+-0.77 km.s-1.Mpc-1)
    • at time t ~ 16 Gyrs -> H ~ 61.7 km.s-1.Mpc-1

    Kind regards

  • Victor Ostrovskii added an answer:
    6
    Who will assist me in developing a new theoretical concept on our oceans' formation - ?

    Hello and thank you for welcoming me here.

    I am thrilled to announce that I seem to have developed an in itself seemingly "water-proof" raw theory on the formation of our (and any) planet's oceans. (Please check the attached file for a short rough concept paper).

    So far, noone I know was able to refute it - so I now seem to need some mathematical and educated assistance/peer review for further development into a proper scientific paper (lacking the skill set in mathematics and detailed education).

    The job would be, to discuss/"bombard" my ideas from a professional point of view, to assess and futher expand my source material for my upcoming long form of the attached, at this point still source-bare concept paper, and to do some math, where necessary. My goal (or you might call it "dream") would be an accepted article in a renowned science magazine.

    If there is anyone out there, willing to partner up - please let me know. I would offer a full equal partnership in this brand-new theory (already documented in different locations on the web, in its raw colloquial form). Even one single trained helper might suffice, as of now. It would literally mean "the world" to me :-) – and maybe to all of us, if you agree in the validity of the thoughts conveyed. Not a small thing, is it?

    Nicolai Herrmann

    Victor Ostrovskii

    Dear Nicolai, 

    Thank you and, please, accept my best wishes for a pleasant and successful New Year.   

  • Victor Ostrovskii added an answer:
    33
    The sun is a critical fusion reactor and needs negative feedback control. How does the sun stabilize itself?
    Negative feedback is essential for the steady state operation of any dynamic system. The sun generates heat based on nuclear fusion. Therefore the sun is a nuclear reactor operating in a critical condition. How does the sun remain stable? What mechanisms are the control feedback of sun?
    Victor Ostrovskii

    Dear Parviz Parvin ,

    According to the PFO-CFO Theory, all chemical elements for each stellar system are formed by the system-forming star with no fusion reactions. You can acquaint yourself with the PFO-CFO Theory and with the mechanisms of element formation through 2010-2015 publications available in my or Elena Kadyshevich pages at the ResearchGate site. This theory rejects big bang, dark matter, dark energy, and black holes. Solar heat energy, luminosity, and neutrino result from radiochemical reactions. This theory is capable of solving your question. 

  • Victor Ostrovskii added an answer:
    6
    Why are there differences in gases in different galaxies?
    There are many observed gases in different galaxies; however there are differences in these gases what do you think is the cause of these differences?
    Victor Ostrovskii

    Dear Sadeem Fadhil ,

    According to the PFO-CFO Theory, all chemical elements for each stellar system are formed by the system-forming star with no fusion reactions and, in the first period of the life of a star, the older is this star, the heavier atoms it forms. You can acquaint yourself with the PFO-CFO Theory and with the mechanisms of element formation through 2010-2015 publications available in my or Elena Kadyshevich pages at the ResearchGate site. This theory is capable of giving the answer to your question. 

  • Victor Ostrovskii added an answer:
    64
    Can the initial singularity be removed from cosmology models?

    In a rather old paper, Michael Heller argues that in certain cases it is possible to remove the initial singularity from cosmology models. He discusses b-boubdary and noncommutative geometry. So what do yo think?

    Victor Ostrovskii

    Dear Victor Christianto,

    Yes, of course. See my or Elena Kadyshevich publications about the PFO-CFO Theory in our pages of the ResearchGate site. 

  • Victor Ostrovskii added an answer:
    20
    Could dark matter originate from normal stars in unknown nuclear processes, before being released?
    Really I can't see any other possible source for it, unless these dark particles have been present since the origin of the Universe.

    What does the scientific community say about this?

    What is more, I have heard about hydrogen plasma (core of most stars), which under certain conditions may occupy abnormal level states such as hydrinos, which break actual physics laws.
    Victor Ostrovskii

    Dear Judit Camacho,

    I advise you to acquaint yourself with the PFO-CFO Theory through publications available at my or Elena Kadyshevich pages at the ResearchGate site. The PFO-CFO Theory explains the Universe formation with no big bang, dark matter, dark energy, and black holes. May be, this theory will be more pleasant for you than the explanation of formation of the Universe on the basis of big bang. 

  • Victor Ostrovskii added an answer:
    16
    What types of organic polymers made or found on Earth have affinities to those found in insoluble organic residues from carbonaceous meteorites?

    Insoluble organic matter residues are the remaining insoluble organic material after extreme acid digestion of the extraterrestrial material. They contain complex morphologies that exist as either: isolated spherical compounded shapes; hollow spherical objects or irregular (non spherical) shapes which internally often contain the same conglomeration of spherical features. Please see attached DF STEM images of some of these morphologies from two organic rich carbonaceous chondrites. As the residues are a product of the removal of surrounding mineralogy (i.e. context in situ is lost), connected features on the submicron to micron scale in the images, by approximation, should only be considered. Thanks!   

    Victor Ostrovskii

    Dear Hitesh,

    As for the direct answer to your question, this is a case when I agree with Dr. Kenneth M. Towe.

    If you are interested in the theory of living-matter formation anywhere in Universe, I advise you the works on the LOH-Theory. The publications are available in my pages at the ResearchGate site. 

  • Victor Ostrovskii added an answer:
    3
    How does the chemistry of the secondary MS star change before and after the CE phase?

    I am trying the understand the chemical evolution of the secondary MS star of a pair of close MS binary. When the primary star evolved and had the envelope ejected, C/N/O would be accreted by the secondary hence there would be enrichments (Marks & Sarna 1998). However, what happens to the heavier elements, do we assume the primary and secondary MS stars have the same, for example, [Fe/H] throughout the evolution?

    Victor Ostrovskii

    Dear Marco,

    May be, chemical evolution of stars, according to the PFO-CFO Theory of Solar System Formation and Transformation (see the publications of 2010-2015 in my or Elena Kadyshevich’s pages at the ResearchGate site), will be more understandable and pleasant for you. It is original theory of Universe formation and transformation from the Beginning up to our days and future.  This is a theory for young and curious researchers free of biases. 

  • Victor Ostrovskii added an answer:
    34
    Why Einstein-theory should not be wrong?
    (open question to "open" points of view: as to say again: relativity.......)
    Victor Ostrovskii

    Dear All, 

    I wrote repeatedly that, in my opinion, the model that underlies the GR is physically doubtful as applied to Universe and, therefore, the applicability of its resulted combined equations for any explanations or predictions of phenomena out of the Solar System is under question. Below, I explain my opinion.

    According to the GR, light propagates over Space in straight lines and with the constant speed. Meanwhile, it is well known that light interacts with gravitation fields (GFs) and deviates in them from straight lines. Apparently, there are no doubts that each stellar system has its own gravitational potential (GP) and each galaxy has its own mean GP. Mathematically, it is possible to take approximately that the GFs are localized. However, physically, GFs are infinite. Thus, Space is under an effect of a sum of more or less weak GFs and, apparently, is gravitationally heterogeneous. If it is so, light should propagate over Space in nonstraight lines and with nonconstant linear speeds. Indeed, the GFs are weak over the major portion of Space; however, the distances are great and the total effects of gravitation may be significant. I saw discussion of this question in the literature.  

  • George Dishman added an answer:
    6
    What is the time - counted from Big Bang - of end of decoupling of photons and baryons ?

    According to the Wilkinson Microwave Ansotropy Probe mission (WMAP), the time most likely for a given CMB photon to last scatter during the period of decoupling of photons and baryons is 372 000 years. This figure corresponds to a maximum probability. However, still following WMAP, the period of decoupling lasted at least 115 000 more years after this maximum until the probability curve of last scattering of a CMB photon reached a value of 1/2 the maximum. This brings us to 487 000 years. What about further reaching 1/10 or 1/20 of the maximum ? Could it bring us to 600 000 or 700 000 years ? Does it make sense to consider that full decoupling of photons and  baryons is not actually realized before such times ?       

    George Dishman

    I usually say it happened "after 380,000 years, over a period of about 140,000 years". For the non-scientists I talk to, that's usually more than they want to know. If you want to go to percentages, then you need a graph of the ionization fraction versus time, IIRC, it's not symmetrical about the 50% time. Note also most of these numbers are not measured, they are calculated from theory based on the time of the mean so "accuracy of results" is somewhat misleading.

  • Christian Baumgarten added an answer:
    99+
    How many dimensions are there in the universe?
    In particular, why do we only experience three spatial dimensions in our universe, when superstring theory, for instance, claims that there are ten dimensions — nine spatial dimensions and a tenth dimension of time?
  • Roger M. Pearlman CTA added an answer:
    41
    Is Hubble's Constant really a constant? Or just a parameter?
    Hubble's constant gives the expansion rate of the universe and the universe is accelerating. So does it mean that the Hubble's constant itself is changing? Why call it a constant then?
    Roger M. Pearlman CTA

    an alternate cosmological redshift hypothesis 'The Pearlman Spiral' if valid would mean it is a somewhat static universe since the end of the inflation epoch, and mean there is no Hubble expansion.

  • Maria Thomas added an answer:
    1
    Websites with list of conferences
    I've found a couple of places that collect announcements for conferences in Astronomy:

    * The International Astronomy Meetings List (CADC) - http://cadcwww.dao.nrc.ca/meetings/
    * Conference Service Mandl - http://www.conference-service.com/conferences/gravitation-and-cosmology.html
    * Astronomy Conferences Worldwide - http://www.conferencealerts.com/astro.htm
    Maria Thomas

    Here is a comprehensive summary over the topics and countries:

    http://www.conference-service.com/conferences/

  • Manuel Morales added an answer:
    22
    Why does Hawking attack philosophy and endorse M-Theory?
    Scientist should not be selective about what is considered philosophy. M-Theory is a philosophy and Hawking's work is also a philosophy. Hawking Radiation has never been detected and most likely never will.
    Manuel Morales

    If a hypothesis cannot be tested, it is not science.

    Case in point, the "Flawed Scientific Method" document was designed to go with the public invitation to help science self-correct. In essence, this one page document illustrates for the public the mechanics of the discovery of Einstein's nonlocal hidden variables which in turn revealed how the scientific method is flawed and how to fix it (see "A Flawed Scientific Method" below).

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Albert Einstein held the belief that quantum mechanics was an incomplete theory and that there were local hidden variables that would give us a complete sense of reality. As the findings show, he was correct about there being hidden variables. However, he was incorrect as to where to find them. The basketball examples serve to illustrate the findings of the Tempt Destiny experiment and the mechanics involved. The "Flawed Scientific Method" illustrations were designed to go with the public invitation to help science self-correct. In essence, this one page document illustrates for the public the mechanics of the discovery of Einstein's nonlocal hidden variables which in turn revealed how the scientific method is fundamentally flawed and how to fix it.
      Full-text · Dataset · Nov 2015

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  • Fabio Salvaggio added an answer:
    12
    There is a dark ring on an asteroid, is it noise in the picture? or not?

    Hello, As you can see in the picture, there is a dark ring on an asteroid, is it noise in the picture? or something else? totally it is like a ring not a burned pixel. 

    Fabio Salvaggio

     Can be a regio with a different albedo. 

    Or, as the others said, a flat issue.

  • Diego Sebastian Mahecha added an answer:
    19
    Is there a definition of 'life' sufficiently encompassing for terrestrial life and possible extra-terrestrial life?
    How we define life? Does it determine what are we going to seek in other worlds? The life on Earth is, for now, our only benchmark, but is there something universally common to the phenomena which we label as life (real or hypothetical) to be considered as a universal definition for life?
    Diego Sebastian Mahecha

    The terrestrial genetic code existed even before the earth scenario. The code existed even before of what we can consider life, or living matter. Here I share with you a recent paper of my own authorship, where it demonstrates that the probability of life tends to zero than to one and it includes more details about similar topics.

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      ABSTRACT: The search for intelligent life or any type of life involves processes with nonlinear chaotic behaviours throughout the Universe. Through the sensitive dependence condition, chaotic dynamics are also difficult or impossible to duplicate, forecast and predict. Similar evolution patterns will result in completely different outcomes. Even, the intelligent life evolution pattern, based on carbon, DNA–RNA–protein, will differ from all possible sequences. In the present paper, the stochastic dyadic Cantor set models the many possible variations of such chaotic behaviours in the Universe, yielding to a tendency to zero, for any scenario of intelligent life evolution. The probability of the development of the exact microscopic and macroscopic scenario that is capable of supporting intelligent life or any other type of life in any planet is vanishingly small. Thus, the present analysis suggests that mankind, as an extremely statistically uncommon occurrence, is unique and alone in the Universe.
      Full-text · Article · Oct 2015 · International Journal of Astrobiology
  • Victor Christianto added an answer:
    21
    Is there global gravitational potential associated with local galactic cluster and beyond?

    In an old paper, Dr. D.V. Ahluwalia suggests that the Great Attractor embeds us in gravitational potential at the order of -3x10^(-5).

    Interestingly, one of my colleague (Michael Peck) also suggestes that there could be global gravitaional potential affecting the entire Universe. So what di you think?

    Victor Christianto

    Dear Dr. Ostrovskii:
    Thanks, yesterday i just downloaded your paper on PFO theory, will find time to read it.

    Btw, you can find my recent question here: https://www.researchgate.net/post/Is_methodological_atheism_required_for_natural_science_especially_cosmology

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