Big Bang Cosmology Intelligent Design Physics

Sabine Hossenfelder asks: Will the Big Bang repeat?

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Roger Penrose’s theory that argues that the Big Bang will repeat is called “conformal cyclic cosmology” and Hossenfelder has her doubts about it. After summarizing the theory, she says, in part,

If the previous eon leaves information imprinted in the next one, then it isn’t obvious that the cycles repeat in the same way. Instead, I would think, they will generally end up with larger and larger fluctuations that will pass on larger and larger fluctuations to the next eon because that’s a positive feedback. If that was so, then Penrose would have to explain why we are in a universe that’s special for not having these huge fluctuations.

Another issue is that it’s not obvious you can extend these cosmologies back in time indefinitely. This is a problem also for “eternal inflation.” Eternal inflation is eternal really only into the future. It has a finite past. You can calculate this just from the geometry. In a recent paper Kinney and Stein showed that this is also the case for a model of cyclic cosmology put forward by Ijjas and Steinhard has the same problem. The cycle might go on infinitely, alright, but only into the future not into the past. It’s not clear at the moment whether this is also the case for conformal cyclic cosmology. I don’t think anyone has looked at it.

Finally, I am not sure that CCC actually solves the problem it was supposed to solve. Remember we are trying to explain the past hypothesis. But a scientific explanation shouldn’t be more difficult than the thing you’re trying to explain. And CCC requires some assumptions, about the conformal invariance and the erebons, that at least to me don’t seem any better than the past hypothesis.

Sabine Hossenfelder, “Will the Big Bang repeat?” at BackRe(Action)

You may also wish to read: The Big Bang: Put simply, the facts are wrong.

2 Replies to “Sabine Hossenfelder asks: Will the Big Bang repeat?

  1. 1
    bornagain77 says:

    As to:

    Sabine Hossenfelder Asks: Will The Big Bang Repeat? – February 28, 2022
    Excerpt: Eternal inflation is eternal really only into the future. It has a finite past. You can calculate this just from the geometry. In a recent paper Kinney and Stein showed that this is also the case for a model of cyclic cosmology put forward by Ijjas and Steinhard has the same problem. The cycle might go on infinitely, alright, but only into the future not into the past. It’s not clear at the moment whether this is also the case for conformal cyclic cosmology. I don’t think anyone has looked at it.
    https://uncommondescent.com/intelligent-design/sabine-hossenfelder-asks-will-the-big-bang-repeat/

    And here is the recent Kinney-Stein paper that disconfirms the cyclical model that she is referring to

    Cyclic Cosmology and Geodesic Completeness – William H. Kinney, Nina K. Stein – Oct 28, 2021
    Abstract:
    We consider recently proposed bouncing cosmological models for which the Hubble parameter is periodic in time, but the scale factor grows from one cycle to the next as a mechanism for shedding entropy. Since the scale factor for a flat universe is equivalent to an overall conformal factor, it has been argued that this growth corresponds to a physically irrelevant rescaling, and such bouncing universes can be made perfectly cyclic, extending infinitely into the past and future. We show that any bouncing universe which uses growth of the scale factor to dissipate entropy must necessarily be geodesically past-incomplete, and therefore cannot be truly cyclic in time.
    https://inspirehep.net/literature/1955797

    The first reference in the preceding paper is the Borde, Guth, Vilenkin paper,

    Inflationary Spacetimes Are Incomplete in Past Directions
    Arvind Borde, Alan H. Guth, and Alexander Vilenkin – 15 April 2003
    Abstract:
    Many inflating spacetimes are likely to violate the weak energy condition, a key assumption of singularity theorems. Here we offer a simple kinematical argument, requiring no energy condition, that a cosmological model which is inflating—or just expanding sufficiently fast—must be incomplete in null and timelike past directions. Specifically, we obtain a bound on the integral of the Hubble parameter over a past-directed timelike or null geodesic. Thus inflationary models require physics other than inflation to describe the past boundary of the inflating region of spacetime.
    https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.90.151301

    And in the following paper, Borde, Guth, Vilenkin further stated that, “This is a stronger conclusion than the one arrived at in previous work [8] in that we have shown under reasonable assumptions that almost all causal geodesics, when extended to the past of an arbitrary point, reach the boundary of the inflating region of spacetime in a finite proper time ”

    Inflationary spacetimes are not past-complete – 2003
    Arvind Borde,1, 2 Alan H. Guth,1, 3 and Alexander Vilenkin1
    Excerpt: we will construct a definition for H that depends only on the relative motion of the observer and test particles.
    In order to motivate what we do, we first consider the case of nonrelativistic velocities in Minkowski space. Suppose that the observer measures the velocities of the test particles as a function of the time t on his own clock.,,,
    IV. Discussion. Our argument shows that null and time- like geodesics are, in general, past-incomplete in inflationary models, whether or not energy conditions hold, provided only that the averaged expansion condition Hav > 0 holds along these past-directed geodesics. This is a stronger conclusion than the one arrived at in previous work [8] in that we have shown under reasonable assumptions that almost all causal geodesics, when extended to the past of an arbitrary point, reach the boundary of the inflating region of spacetime in a finite proper time (finite affine length, in the null case).
    https://www.brainmaster.com/software/pubs/physics/Inflation%20past0110012v2.pdf

    Prior to this work by Borde, Guth, Vilenkin establishing, via Special Relativity, that the universe must have had an absolute beginning, Hawking, Penrose and Ellis, via General Relativity, (circa 1970), also proved that “time and space had a finite beginning that corresponded to the origin of matter and energy.”

    Big Bang Theory – An Overview of the main evidence
    Excerpt: Steven Hawking, George Ellis, and Roger Penrose turned their attention to the Theory of Relativity and its implications regarding our notions of time. In 1968 and 1970, they published papers in which they extended Einstein’s Theory of General Relativity to include measurements of time and space.1, 2 According to their calculations, time and space had a finite beginning that corresponded to the origin of matter and energy.”3
    Steven W. Hawking, George F.R. Ellis, “The Cosmic Black-Body Radiation and the Existence of Singularities in our Universe,” Astrophysical Journal, 152, (1968) pp. 25-36.
    Steven W. Hawking, Roger Penrose, “The Singularities of Gravitational Collapse and Cosmology,” Proceedings of the Royal Society of London, series A, 314 (1970) pp. 529-548.
    http://www.big-bang-theory.com/

    And in the following fairly recent video, Dr. Stephen Meyer explains why the Borde, Guth, Velinken theorem turns out to be a much stronger proof for an absolute beginning for the universe than the previous proof from Hawking, Penrose and Ellis was.

    “There is another development in theoretical physics called the Borde, Guth, Vilenkin theorem. And its not based on General Relativity but its based on Special Relativity. And for that reason it is not effected by postulations about what gravity might or might not have been like in the first tiny smidgen of time after the beginning of the universe. And it is those speculations that prevented the Hawking, Penrose, Ellis, singularity theorem from absolutely proving a beginning point.
    Instead the Borde, Guth, Vilenkin, theorem proves a beginning to the universe on the basis of considerations from special relativity that have nothing to do with whether or not there were quantum fluctuations within the first tiny smidgen of time after the beginning of the universe, and whether gravity might have worked differently or not. Instead it is independent of all those kind of considerations and caveats that prevent us from saying that the Hawking, Penrose, Ellis, results are absolute proofs (for a beginning of the universe). Instead you have a very strong proof of a beginning from theoretical physics that is not dependent on these conditions.”,,,
    – Stephen Meyer Discusses the Big Bang, Einstein, Hawking, and More – video – 36:42 minute mark
    https://youtu.be/m_AeA4fMHhI?t=2202

    Also of note: Brian Miller recently listed some fairly devastating problems with Penrose’s current CCC model that also render it untenable as a serious scientific theory. Most importantly, and devastating for Penrose’s theory, is that CCC “contradicts the empirical evidence.”

    Another Attempt by an Esteemed Cosmologist to Avoid a Cosmic Beginning Collapses on Inspection
    – Brian Miller – January 11, 2022
    Excerpt: But CCC is founded on numerous highly dubious assumptions, and it contradicts the empirical evidence.,,,
    ,,,”The predictions that he’s made are refuted by the data, and his claims to see these effects are only reproducible if one analyzes the data in a scientifically unsound and illegitimate fashion. Hundreds of scientists have pointed this out to Penrose — repeatedly and consistently over a period of more than 10 years — who continues to ignore the field and plow ahead with his contentions.”
    – Ethan Segal,,,
    Questionable Assumptions
    An additional problem is that Penrose’s model requires several highly questionable assumptions. First, it must overcome the implications of the Borde-Guth-Vilenkin theorem that proves that expanding universes must have an absolute beginning. To avoid this conclusion, Penrose must assume that the universe was infinitely large in the infinite past, which is philosophically problematic. Additional unproven assumptions include the following:
    *All particle masses dropping to zero.
    *Presence of a scalar field that becomes active at the right time to trigger crossover.
    *Mass of the scalar field rapidly increases after crossover.
    Given the lack to supporting evidence and the ad hoc assumptions, CCC offers no serious challenge to the evidence that the universe had a beginning. Therefore, something, or more likely someone, outside of time and space must have created it.
    https://evolutionnews.org/2022/01/another-attempt-by-an-esteemed-cosmologist-to-avoid-a-cosmic-beginning-collapses-on-inspection/
    Dr. Brian Miller holds a B.S. in physics with a minor in engineering from MIT and a Ph.D. in physics from Duke University.

    As to Sabine Hossenfelder’s observation that, “You can calculate this just from the geometry”, well, it is now also proven, via the extension of Godel’s incompletenesss into quantum physics, that any ‘geometry’ of any universe cannot be explained by reference to ‘bottom-up’ naturalistic processes.

    Specifically, it is now proven that “even a perfect and complete description of the microscopic properties of a material is not enough to predict its macroscopic behaviour.,,,” and that “the insurmountable difficulty lies precisely in the derivation of macroscopic properties from a microscopic description.”

    Quantum physics problem proved unsolvable: Gödel and Turing enter quantum physics – December 9, 2015
    Excerpt: A mathematical problem underlying fundamental questions in particle and quantum physics is provably unsolvable,,,
    It is the first major problem in physics for which such a fundamental limitation could be proven. The findings are important because they show that even a perfect and complete description of the microscopic properties of a material is not enough to predict its macroscopic behaviour.,,,
    “We knew about the possibility of problems that are undecidable in principle since the works of Turing and Gödel in the 1930s,” added Co-author Professor Michael Wolf from Technical University of Munich. “So far, however, this only concerned the very abstract corners of theoretical computer science and mathematical logic. No one had seriously contemplated this as a possibility right in the heart of theoretical physics before. But our results change this picture. From a more philosophical perspective, they also challenge the reductionists’ point of view, as the insurmountable difficulty lies precisely in the derivation of macroscopic properties from a microscopic description.”
    http://phys.org/news/2015-12-q.....godel.html

    The overriding principle behind the preceding finding is really not all that hard to understand,

    “There cannot be, in principle, a naturalistic bottom-up explanation for immutable physical laws — which are themselves an ‘expression’ of top-down causation. A bottom-up explanation, from the level of e.g. bosons, should be expected to give rise to innumerable different ever-changing laws. By analogy, particles give rise to innumerable different conglomerations.
    Moreover a bottom-up process from bosons to physical laws is in need of constraints (laws) in order to produce a limited set of universal laws.
    Paul Davies: “Physical processes, however violent or complex, are thought to have absolutely no effect on the laws. There is thus a curious asymmetry: physical processes depend on laws but the laws do not depend on physical processes. Although this statement cannot be proved, it is widely accepted.”
    Saying that laws do not depend on physical processes, is another way of saying that laws cannot be explained by physical processes.”
    – Origenes – UD blogger

    In short, and in conclusion, atheistic naturalists who desperately want to avoid an absolute beginning of the universe, in order to avoid the obvious Theistic implications therein, have been stopped dead in their tracks at every turn.

    As Alexander Vilenkin noted elsewhere, “There is no escape, they, (cosmologists), have to face the problem of a cosmic beginning.”

    “It is said that an argument is what convinces reasonable men and a proof is what it takes to convince even an unreasonable man. With the proof now in place, cosmologists can long longer hide behind the possibility of a past eternal universe. There is no escape, they have to face the problem of a cosmic beginning.”
    – Alexander Vilenkin – Many Worlds In One – Pg. 176?

    Verse and Quote:

    Genesis 1:1
    In the beginning God created the heavens and the earth.

    “My argument,” Dr. Penzias concluded, “is that the best data we have are exactly what I would have predicted, had I had nothing to go on but the five books of Moses, the Psalms, the Bible as a whole.”
    – Dr. Arno Penzias, Nobel Laureate in Physics – co-discoverer Cosmic Microwave Background Radiation – as stated to the New York Times on March 12, 1978

  2. 2
    BobRyan says:

    No matter how the universe began, which is unlikely to be Big Bang due to new evidence that is being ignored, the universe has a beginning. Just like the laws of physics had to have a beginning, including energy that cannot be created. With God, all things are possible, including the creation of energy. With man, not so much. The laws cannot be violated or broken in any way.

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