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Thread: The Beginning of the universe

  1. #1
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    The Beginning of the universe

    Quote:
    Originally Posted by Cougar
    The current view of the big bang is that everything resulted from this one event,

    Quote Originally Posted by Spaceman Spiff
    This is a little off topic - but since it came up, and people are commenting on it, let me try to clear up this misconception, by giving an opinion from the point of view of a research astronomer.

    The "big bang" theory in its present form does not address this (quoted above) at all. At its most general level, the theory says that space-time is dynamic and that such dynamics are described well by the Theory of General Relativity. At a slightly less general level it says that the present observable universe is expanding and at some time in the past was in a hot dense state, and that evidence for both are observables/measureables. It does not demand that the Friedmann-Robertson-Walker solutions to the field equations must be the correct ones describing the dynamics of space-time on the large scales - even if these are the solutions that the current paradigm works (well) within. It does not say ab initio how or why it started in a hot dense state, what precisely this "initial" state was, nor does it say that this "event" was singular (and it doesn't say that it arose from a singularity, either). A larger, more general, more encompassing theory might eventually address items such as "initial" conditions, etc, subsuming/incorporating the big bang theory in the process.

    "Big Bang" is a curse of a name for this scientific theory - a name that Hoyle saddled on it. I've often observed people arguing over or being confused by issues that are non-issues because of their preconceptions they bring when hearing the name of this scientific theory of astronomy. One must always be careful to try to separate a scientific theory of nature from somebody's interpretation of "what it means".

    Sorry for wandering a bit off the main road here, but I hope this was helpful.

    First, very nice Web Site Spaceman Spiff! Many great links there!

    Please don't take any of this the wrong way!!!

    But, this kind of explanation is VERY dangerous to the truth ( I assume that is what we are all really looking for, right?) of how the universe works!
    Now, Why do I say that?

    First, I do realize that the Big Bang has never said that a singularity actually started our universe (Just so you, Tensor, and Nereid don't assume that I misunderstand)

    Answer this honestly, and you will realize why (hopefully).

    Ever since Einstein's GR came to fruition, Hubble found the galaxies to be expanding, and Friedmann 'proposed' his singularity, to start the universe, from that time, 192? to 1962, the year before Penzias and Wilson, what was the justification for the "HOT" primordial TEV Gamma Radiation???

    Respond to this and Cougar's first 3 minutes, and then we can continue, if that is okay.

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    RussT:

    I honestly don't know what more you want me to comment on. I've tried to lay out a careful and general description of the scientific theory known as the "Big Bang", unburdened by undue interpretation. If that description is not somehow ok for you, then I don't know what else to say.

    As for Cougars "First 3 Minutes" - this in a nutshell is what I told him in a private communique after the original forum was locked and before this discussion was moved here:

    My attempt to carefully describe the "Big Bang" Theory (although likely still flawed) is not outside the mainstream at all. It does not run counter to Weinberg's "The First 3 Minutes". For example, Steinhardt's & Turok's "Ekpyrotic" universe scenario predicts many "big bangs" (maybe infinite) - and it does not run counter to the predictions of cosmonucleosynthesis, or if it had it would have been DOA instead of being a competitor with the various scenarios of Inflation. So cosmonucleosynthesis happened in the first 3 minutes after "our universe" began expanding/cooling. From what 'initial' state? It's not yet known. Present observational constraints (cosmic background radiation, abundances of the lightest elements, number neutrino flavors, properties of protons & neutrons and their quarks...) coupled with reasonably well-constrained physics take us back to a time when the temperature was everywhere ~10^13 K (about 1 GeV), some 10^-4 s after this universe began expanding/cooling.

    This problem of mistaking a scientific theory for interpretations of "what it means" is common - quantum mechanics is another example.
    Last edited by Spaceman Spiff; 2006-May-24 at 02:06 AM.

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    Quote Originally Posted by Spaceman Spiff
    I honestly don't know what more you want me to comment on.
    I am really not trying to be confrontational here, just clear and precise!

    I was simply asking you if you could 'honestly' answer the question...
    [Ever since Einstein's GR came to fruition, Hubble found the galaxies to be expanding, and Friedmann 'proposed' his singularity, to start the universe, from that time, 192? to 1962, the year before Penzias and Wilson, what was the justification for the "HOT" primordial TEV Gamma Radiation???]

    Which you didn't even address.

    That is, I presume, because you understand that there is only one reasonable answer to this...that before 1963 (CMB) it was presumed that the singulariity was the justification for the HOT primordial beginning!

    This is the "HONEST" answer, and I am not 'confused here! How many gazillion times has the question...at what point in space did the singularity happen??? And the first 30 years it was the answer for where the Hot primordial Matter came from!

    This is why I am saying that this is very dangerous to cosmology, and you of course, are not the only one doing this. Others in this forum are even more adament, with some going so far as to say that the Friedmann Naked Singularity has never even been part of the Big Bang Theory!

    The point to this is that the CMB, although it does 'appear' to be evidence, it does not PROVE a Hot beginning. The bigger point here is, if there is a different application of GR (and what are the odds that Gr was applied correctly to the universe as a whole, right out of the box? and yes, this is leading to that), it is very important, that how the current view came to be the way it is, not be skewed, so that the correct view of "How The Matter Gets Here", can be compared to the current view correctly, which is what we all want, right? To understand the universe correctly?

    So, here is one version that seems to fit that bill.http://www.absoluteastronomy.com/enc2/big_bang

    Before the late 1960s many cosmologists thought the infinitely dense and physically paradoxical singularity at the starting time of Friedmann's cosmological model could be avoided by allowing for a universe which was contracting before entering the hot dense state and starting to expand again. This was formalized as Richard Tolman's oscillating universe. In the sixties, Stephen Hawking and others demonstrated that this idea was unworkable, and the singularity is an essential feature of the physics described by Einstein's gravity. This led the majority of cosmologists to accept the notion that the universe as currently described by the physics of general relativity has a finite age. However, there is no way to say whether the singularity is an actual origin point for the universe or whether the physical processes that govern the regime cause the universe to be effectively eternal in character.

    And Here is another.
    http://www.bautforum.com/showpost.ph...1&postcount=66

    I am going to let you respond to this, and then I will continue, if that's okay with you.

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    I don't quite understand the question, so what I'll write here may be quite wide of the mark (if so, please clarify what it is that you're asking, RussT).

    On the one hand, we have a whole lot of observational data, from the fine details of the CMB, through a gazillion spectra, images, etc ... crudely, you can lump them into four categories - observations of the CMB, of the large-scale structure of the (observable) universe, of the primordial abundance of light nuclides, and of the Hubble relationship.

    On the other hand, we have the two most successful theories of physics, to date - quantum theory and General Relativity.

    On the third hand, we have many sets of detailed observational and experimental results, which serve as the interlocking consistency elements, the sanity checks, and so on, of 'CMB, primordial abundance, large-scale structure, and Hubble relationship observations' (these sets of results are often not mentioned at all in popsci accounts, and trivialised or ignored by ATMers; yet they play very important roles in establishing the 'headline' results).

    On the fourth hand, we have a great deal of material from lab experiments on what happens when matter gets hot, right up to GeV temperatures.

    The challenge the modern cosmologist faces is to put all these pieces together, to form a coherent story, one that is internally consistent, and consistent with the huge number of good experimental and observational results.

    The result is a model (actually many different models) of the universe, its structure and evolution.

    There are many limits to this model. For example, the period before the surface of last scattering cannot (yet) be probed by direct observation; the physics of (baryonic) matter in equilibrium states where the temperature is >~a few GeV is essentially unknown; the nature of Dark Matter and (especially) Dark Energy is uncertain, especially at high temperatures and densities.

    Astronomers and physicists are keen to push these limits back, and are working hard to do so. Some 'in principle' observations are 'to die for' - e.g. the neutrino equivalent of the CMB, observed with the same degree of resolution (spectrum, temperature variations, angular variations, and so on) as currently achieved by WMAP.

    I would say that all professionals are well aware of the limits of the models, and if given a chance to explain them, can lay them out in considerable detail.

    One limitation that is perhaps more fundamental than the others is the lack of a quantum theory of gravity (or equivalent - something which unified quantum theory with GR). The physical regimes in which these two spectalularly successful theories are mutually incompatible, to the point of rendering even OOM predictions meaningless, are well known. If the best cosmological models are extrapolated, they all (AFAIK) encounter such regions.

    This means that any scientific statement about the nature, history, whatever of the universe 'beyond' these regions must be accompanied by lots of caveats and qualifications ... especially around what kinds of theories of quantum gravity have been assumed.

    I hope this helps.

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    Quote Originally Posted by Nereid
    I hope this helps.
    Helped with what Nereid? You know I understand all of these generic expanations of how mainstream cosmology is so on the right track!

    Both of you have totally dodged (I don't understand the question) having to answer...what was the justification for the "HOT" primordial beginning from 1927 to 1962, before the CMB was found and Inflation was invented (1980), which is fine, because there is only one answer for that, the singularity, that you Tensor and now Spaceman Spiff, are so adamant about denying was ever even part of the GR application to the universe as a whole.

    Every theory that has started out talking about the beginning or near beginning of the 'universe as a whole', has been shown to be wrong, so, what are the chances that the very first attempt once Einstein's GR came to frution, of applying that to the 'universe as a whole', are correct? Now, you can say that there have been many GR models considered, but they all have the same lookback scenario, the universe condensed down to a small HOT dense beginning, or as you gals would say, near beginning, because we can't know what happened before 10 ^-43.

    http://www.jb.man.ac.uk/~jpl/cosmo/friedman.html#intro

    So, that brings us to the 2 main reasons I took your advice, and moved this to where you suggested. Fortunately, Spaceman Spiff, an accredited Professor and research scientist, who I assume would be a valued member of this forum, searched around enough to find this moved continuation of one of his posts, after the thread was closed for being 'off topic', when the original poster had never even made another post in that thread.

    Moving to main reason #1. You Keep quoting these, and rightfully so, which should mean, that as long as I am talking GR, I am talking mainstream!
    Quote Originally Posted by Nereid
    On the other hand, we have the two most successful theories of physics, to date - quantum theory and General Relativity.
    So, I am going to main reason #2, and I am going to make several statements here, and hopefully, even though you responded to my response to Spaceman Spiff, he will continue also.

    First, mainstream, as I have said before, has done a superlative and outstanding job of getting us where we are today in cosmology (accomplishments way to lengthy to list), but, IMHO, by far the single biggest accomplishment (and brought forward and reported on with great integrity, concidering they cannot even explain how they occur), is figuring out through the correct modeling of GR, and then through diligent experiments and remarkable advancements in telescopes, actually determined that SMBH's exist in the cores of regular galaxies!

    Second, now the correct GR modeling of the "REAL" singularity, that mainstream has found, the one that 'really' exists in the depths of the SMBH's, can move forward, and show how this universe of ours truly is, stranger than anyone could have imagined!

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    To RussT:

    I agree with what Nereid said. I really don't understand the point of the leading questions you're asking. I am not denying the things that you're saying I am.

    As data are collected over the decades, scientific theories grow, evolve, mature, merge with others, are subsumed by larger, general, more encompassing theories or whither on the vine. They are never static - except in death. And scientists often extrapolate and speculate from what is understood within the bounds of a descriptive scientific theory (GR in this case) into the realm of the unknown, but as scientists we usually recognize the difference.

    I would argue, and I think many would agree, that the Big Bang Theory did not gain the status of a scientific theory until sometime after the discovery of the cosmic microwave background radiation. Before that it was something that some people (mostly theorists) dabbled around in (although still made some important early yet preliminary findings) - a theory with very little data, and so not a true theory in the scientific sense. And so why is it important whether LeMaitre suggested a "primordial atom" or so-and-so suggested that the universe emerged from a singularity (or whatever)? It doesn't matter - except to historians of science and the scientific process.

    As for the singularities: my understanding is that within the realm of GR (it is not my area of expertise), they are nothing more than extrapolations. The singularities don't actually exist in GR - that's why they are called "singularities", more or less. Many researchers in the field today doubt their existence inside of black holes (stellar or supermassive black holes in the centers of massive galaxies). In any case we (or rather they) await or are actively working on the development of quantum theory of gravity to appropriately address the question. In fact we cannot say we really understand "black holes" at the present time. Chances are they aren't quite the beasts described in the textbooks. So maybe singularities do exist, and maybe they don't - the point is we don't know and the BBT does not require the universe to have started in one (whatever that actually means).
    Let me say again: the BBT does not address this point (pun intended).

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    Quote Originally Posted by Spaceman Spiff
    Let me say again: the BBT does not address this point (pun intended).
    And please allow me to say again, the whole point to the 1927 to 1962 time frame, is that "This Point", was the point, because without it, there was NO justification for the "HOT" very small 10 ^-43 Infinite Energy Density!

    Sure, then came the CMBR, but you all seem to think that is "PROOF"...it's not! It shows that gamma rays have been stretched to the micro wave length from the casual or particle horizon. Are there quasars, blazars, AGN, and GRB's that are farther than that, sending all those Gamma rays from 13 billion plus light years, sure, we all believe that!
    Then came Inflation, to save the day...that is not "PROOF" either! Is the universe HUGE...sure, is it expanding, I think that it most likely is...did it expand exponentially fast in the very first nano-seconds, very questionable, actually!

    Quote Originally Posted by Spaceman Spiff
    The singularities don't actually exist in GR - that's why they are called "singularities", more or less.
    And this is where the real problem is! But here is the trick, and why I am so concerned, and said that this spin control type methodology, of just saying that the singularity was never really part of the BBT, is so dangerous.

    Because to be able to see what is really correct about the singularities in the SMBH's, it has to be able to be talked about and compared to all the modeling that has taken place to try and make it fit the beginning of the universe, as it was proposed to do!

    Now, I agree, that the Friedmann Naked Singularity does not work for T=0, that is the correct conclusion! However, the next conclusion 'they' make is the wrong one!

    http://www.bautforum.com/showpost.ph...1&postcount=66

    This is a quote from Tim's post...
    [Originally Posted by Sean Carroll; 2004
    These solutions all feature a singularity at a=0, known as the Big Bang. It represents the creation of the universe from a singular state, not an explosion of matter into pre-existing spacetime. It might be hoped that the perfect symmetry of our FRW universes is responsible for this singularity, but in fact that's not true; cosmological singularity theorems show that any universe with rho > 0 and p >= 0 must have begun at a singularity. Of course the energy density becomes arbitrarily high as a -> 0, and we don't expect classical general relativity to be an accurate definition of nature in this regime; presumably quantum gravity becomes important, although it is unclear how at the moment.]

    Now, this talks about the comic singularity only (not the ring singularity in a SMBH) and then of course the unification of QFT in the Planck era.

    So the wrong conclusion they come to is simply saying that because the cosmic singularity at T=0 doesn't work, that the singularity in the SMBH must not either!!!

    We can model the singularity in the SMBH just fine with GR, all the math shows the structure...accretion disc/event horizon/massive black hole/ring singularity/worm hole/?...they can't do that with the cosmic T=0 singularity, because it has definitely been shown that the universe is not "IN" a black hole!

    So, the real 'failure' is not GR at the singularity, it is the universe starting at the singularity, which is why they have not been able to unify QFT and GR.

    There is no Planck era to unify in! The extra Gravity, the Dark Matter/Dark Energy, has no way to get here at 10 ^-43! From this time forward, the only thing the Big Bang shows coming into existence is Baryonic Matter!

    I don't necessarily expect you to see all of this right off the bat, but think about this. The unification of QFT and GR is all about the 'extra gravity', and where in the 1st three minutes, or after does the BB show DE/DM coming into the picture? Actually DE, didn't even come into the picture until 1998, with the SN 1a results, showing that the universe was accelerating it's expansion.

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    And this is where the real problem is! But here is the trick, and why I am so concerned, and said that this spin control type methodology, of just saying that the singularity was never really part of the BBT, is so dangerous.
    I am not spinning or parsing anything. If what I said caused you confusion, then let me clarify - the BBT alone does not address initial conditions - whatever they were, be they a singularity - whatever. Other working models out there which incorporate the BBT may attempt to, such as various Inflationary models, so-called Ekpyrotic membrane models, etc. For example, the Ekpyrotic models do not have singularities, but have all of the key components of the BBT: baryogenesis, nucleosynthesis, photon and neutrino backgrounds, etc. But all scientific theories lie within bounds inside of which they are a valid, working explanation of nature based on observation/data. If that's not a satisfactory situation for you, I cannot help it.

    [Originally Posted by Sean Carroll; 2004:
    These solutions all feature a singularity at a=0, known as the Big Bang. It represents the creation of the universe from a singular state, not an explosion of matter into pre-existing spacetime. It might be hoped that the perfect symmetry of our FRW universes is responsible for this singularity, but in fact that's not true; cosmological singularity theorems show that any universe with rho > 0 and p >= 0 must have begun at a singularity. Of course the energy density becomes arbitrarily high as a -> 0, and we don't expect classical general relativity to be an accurate definition of nature in this regime; presumably quantum gravity becomes important, although it is unclear how at the moment.]

    My emphasis.

    We can model the singularity in the SMBH just fine with GR, all the math shows the structure
    No we cannot. GR does not explain singularities, ringed or otherwise; they are simply extrapolations - that's why they are called singularities. In fact I will state that we do not understand the nature of the event horizon of a black hole or the nature of what's inside. Plenty of print has been expended in extrapolating from classical GR to speculate on such matters, but in the end that's what they are - informed speculation. What Sean Carroll said, and I put in bold, is right on the mark.

    Unless somebody else cares to comment, I am through with this thread.
    Last edited by Spaceman Spiff; 2006-May-26 at 03:28 PM.

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    Quote Originally Posted by RussT
    Helped with what Nereid? You know I understand all of these generic expanations of how mainstream cosmology is so on the right track!

    Both of you have totally dodged (I don't understand the question) having to answer...what was the justification for the "HOT" primordial beginning from 1927 to 1962, before the CMB was found and Inflation was invented (1980), which is fine, because there is only one answer for that, the singularity, that you Tensor and now Spaceman Spiff, are so adamant about denying was ever even part of the GR application to the universe as a whole.
    If you apply GR to the universe as a whole, and nothing but GR, you get a singularity, at t = 0 (though the Sean Carroll quote in Spaceman Spiff's post says it better).

    I'm not all that certain of the details of the history of theoretical cosmology, but I'd be astonished to learn that those writing the relevant papers felt it unnecessary to put caveats around any GR singularity, especially the need for a quantum theory of gravity.
    Every theory that has started out talking about the beginning or near beginning of the 'universe as a whole', has been shown to be wrong, so, what are the chances that the very first attempt once Einstein's GR came to frution, of applying that to the 'universe as a whole', are correct? Now, you can say that there have been many GR models considered, but they all have the same lookback scenario, the universe condensed down to a small HOT dense beginning, or as you gals would say, near beginning, because we can't know what happened before 10 ^-43.

    http://www.jb.man.ac.uk/~jpl/cosmo/friedman.html#intro
    I guess it depends somewhat on what you call a theory, and what you call wrong (in one sense every scientific theory ever produced has been shown to be wrong, in one way or another, or will certainly be so shown before too long).

    Cosmology wasn't much of an area in science that could be constrained by observation, other than in very broad terms, until the discovery of the CMB and then the astonishing advances in detector technology, computing power, etc that enabled surveys such as 2dF and SDSS to be carried out. Once hard data starting coming in, models could be refined and tested, just like in any other part of science.
    So, that brings us to the 2 main reasons I took your advice, and moved this to where you suggested. Fortunately, Spaceman Spiff, an accredited Professor and research scientist, who I assume would be a valued member of this forum, searched around enough to find this moved continuation of one of his posts, after the thread was closed for being 'off topic', when the original poster had never even made another post in that thread.

    Moving to main reason #1. You Keep quoting these, and rightfully so, which should mean, that as long as I am talking GR, I am talking mainstream!


    So, I am going to main reason #2, and I am going to make several statements here, and hopefully, even though you responded to my response to Spaceman Spiff, he will continue also.

    First, mainstream, as I have said before, has done a superlative and outstanding job of getting us where we are today in cosmology (accomplishments way to lengthy to list), but, IMHO, by far the single biggest accomplishment (and brought forward and reported on with great integrity, concidering they cannot even explain how they occur), is figuring out through the correct modeling of GR, and then through diligent experiments and remarkable advancements in telescopes, actually determined that SMBH's exist in the cores of regular galaxies!

    Second, now the correct GR modeling of the "REAL" singularity, that mainstream has found, the one that 'really' exists in the depths of the SMBH's, can move forward, and show how this universe of ours truly is, stranger than anyone could have imagined!
    I think these points are addressed in later posts (if not, please say so).

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    Quote Originally Posted by RussT
    And please allow me to say again, the whole point to the 1927 to 1962 time frame, is that "This Point", was the point, because without it, there was NO justification for the "HOT" very small 10 ^-43 Infinite Energy Density!
    I thought Spaceman Spiff's post captured the situation well.

    Rather than "without [the CMBR], there was NO justification for the "HOT" very small 10 ^-43 Infinite Energy Density!", it might be more accurate to say "there was really no way to seriously test predictions from the application of GR to the universe as a whole, until the discovery of the CMBR, so the pretty much the only scientists who did any work in this area were theoreticians." Of course, the origin of the universe is a topic of immense interest to a great many people, other than just theoretical physicists.

    IIRC, there were only two theories that had legs, back then (the observational basis of any cosmologies then included the dark night sky, the Hubble relationship, and a lack of much in the way of elements other than H and He), what we call the Big Bang theory (which is, as you know, a class of theories, not just one) and the Steady State (ironically, it was a leading proponent of the latter who gave the former its now universally accepted name, no matter that he intended it ironically, nor that it is quite misleading!). I'm not sure anything much has changed, other than the various Steady State theories having become not much more than history.
    Sure, then came the CMBR, but you all seem to think that is "PROOF"...it's not! It shows that gamma rays have been stretched to the micro wave length from the casual or particle horizon. Are there quasars, blazars, AGN, and GRB's that are farther than that, sending all those Gamma rays from 13 billion plus light years, sure, we all believe that!
    That's a pretty radical idea, and doesn't seem to resemble any BBT all that closely.

    The CMB's role in cosmology includes its ability to probe conditions of the universe at times earlier than the surface of last scattering, through the angular power spectrum ("fossilised sound waves") and polarisations.

    There's nothing new in terms of 'proof'; any day now an alternative may come along which can account for the CMB (and other good observations) better than the best cosmological models we have today, and 'poof', another theory bites the dust.

    However, until that something better comes along, we'll keep working with those concordance models ...
    Then came Inflation, to save the day...that is not "PROOF" either! Is the universe HUGE...sure, is it expanding, I think that it most likely is...did it expand exponentially fast in the very first nano-seconds, very questionable, actually!
    We ain't got nothing better, yet, so we'll push on this, work out predictions, and test it as vigourously as we possibly can!
    And this is where the real problem is! But here is the trick, and why I am so concerned, and said that this spin control type methodology, of just saying that the singularity was never really part of the BBT, is so dangerous.

    Because to be able to see what is really correct about the singularities in the SMBH's, it has to be able to be talked about and compared to all the modeling that has taken place to try and make it fit the beginning of the universe, as it was proposed to do!
    I don't follow this (and Spaceman Spiff has addressed it, in a later post); the best you can do is account for what you can observe. What happens inside the event horizons of black holes is, AFAIK, quite unobservable, today, with the technology we have.

    Maybe if we could get up very close to a SMBH, or make a mini-BH in the LHC, we might start to be able to test theories about what's inside (or if someone comes up with a good theory of quantum gravity, as in testable).

    Otherwise, surely it's just speculation (even if very interesting speculation)?
    Now, I agree, that the Friedmann Naked Singularity does not work for T=0, that is the correct conclusion! However, the next conclusion 'they' make is the wrong one!

    http://www.bautforum.com/showpost.ph...1&postcount=66

    This is a quote from Tim's post...
    [Originally Posted by Sean Carroll; 2004
    These solutions all feature a singularity at a=0, known as the Big Bang. It represents the creation of the universe from a singular state, not an explosion of matter into pre-existing spacetime. It might be hoped that the perfect symmetry of our FRW universes is responsible for this singularity, but in fact that's not true; cosmological singularity theorems show that any universe with rho > 0 and p >= 0 must have begun at a singularity. Of course the energy density becomes arbitrarily high as a -> 0, and we don't expect classical general relativity to be an accurate definition of nature in this regime; presumably quantum gravity becomes important, although it is unclear how at the moment.]

    Now, this talks about the comic singularity only (not the ring singularity in a SMBH) and then of course the unification of QFT in the Planck era.

    So the wrong conclusion they come to is simply saying that because the cosmic singularity at T=0 doesn't work, that the singularity in the SMBH must not either!!!

    We can model the singularity in the SMBH just fine with GR, all the math shows the structure...accretion disc/event horizon/massive black hole/ring singularity/worm hole/?...they can't do that with the cosmic T=0 singularity, because it has definitely been shown that the universe is not "IN" a black hole!

    So, the real 'failure' is not GR at the singularity, it is the universe starting at the singularity, which is why they have not been able to unify QFT and GR.

    There is no Planck era to unify in! The extra Gravity, the Dark Matter/Dark Energy, has no way to get here at 10 ^-43! From this time forward, the only thing the Big Bang shows coming into existence is Baryonic Matter!
    Little of this makes any sense to me - are you suggesting that there are cosmological theories, consistent with the same things that concordance models are consistent with, that do not include something that unifies quantum theory and GR? If so, have they been published?
    I don't necessarily expect you to see all of this right off the bat, but think about this. The unification of QFT and GR is all about the 'extra gravity', and where in the 1st three minutes, or after does the BB show DE/DM coming into the picture? Actually DE, didn't even come into the picture until 1998, with the SN 1a results, showing that the universe was accelerating it's expansion.
    Since the nature of DM and DE are still pretty much unknown, the question of when either entered the timeline is also unknown (except that they both seem to be there at the time of the CMB).

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    Quote Originally Posted by Nereid
    If you apply GR to the universe as a whole, and nothing but GR, you get a singularity, at t = 0
    Nereid, the first time you made this statement to me, in my A New Perspective thread, or maybe it was my Dark Matter thread, you said...

    "ONE" application of GR is a singularity at T=0. Everytime I have seen you use it since, you have dropped the 'one'.

    There is another alternative that I can show, but I can't because of this...
    Quote Originally Posted by Nereid
    OK, so if there is a theory, internally consistent, consistent with (all) good observational and experimental results (within its domain of applicability), that has the universe started from a {insert set of key concepts here, unfortunately indistinguishable from gibberish with today's science} (or a piece of burnt toast), then we could say 'the universe did not arise from {insert today's front runner, e.g. "an extremely hot dense state"}'.
    You have already made up your mind.

    and this...
    Quote Originally Posted by Nereid
    More generally, the mainstream position is brutally honest - the best theories work well in {regimes that exclude the Planck regime}, and so attempts to apply those theories outside their (known) domains of applicability are invalid/illegal/irresponsible/...
    Here is some brutal honesty, but sincerely said with ALL DUE RESPECT, you and most of the mainstream scientists on Baut have tried to convince 'us', that you are open minded and have not come to any conclusions, but these two quotes above certainly don't back that up.


    There is too much to respond to above, so I'll just make my point of this thread here.

    If mainstream wants to answer...
    How SMBH's are made using GR
    How galaxies are formed and evolve using GR
    How GR and QFT can be unified
    How String/"M" theory can fit this unification
    DM/DE

    Then the only way this can be done, is by having an open and honest discussion about the differences between the proposed Friedmann Naked Singularity and the Singularity that exists in the SMBH's!

    I am say right here, loud and clear, that just because the Big Bang Singualrity could not be made to work for the beginning of the universe, DOES NOT PUT IT IN THE SAME CATEGORY AS THE SINGULARITY IN THE SMBH"S!!!

    And just saying that we cannot observe the inside of a black whole is a huge mistake, and I can show why, now using GR rather than "M" theory, like I was before!

    But alas, most, like Spaceman Spiff, just want to make a few explanations (dismissals and denials), and just go on believing in the magic of the CMBR.


    Quote Originally Posted by RussT
    Sure, then came the CMBR, but you all seem to think that is "PROOF"...it's not! It shows that gamma rays have been stretched to the micro wave length from the casual or particle horizon. Are there quasars, blazars, AGN, and GRB's that are farther than that, sending all those Gamma rays from 13 billion plus light years, sure, we all believe that!
    Quote Originally Posted by Nereid
    That's a pretty radical idea, and doesn't seem to resemble any BBT all that closely.
    Actually, it's not radical at all...do you know of anyone who doesn't believe there are galaxies beyond 13.7 billion light years? So, all it would take, is for the universe to be 16 or 18 billion years old, and all those Quasars, Blazars, AGN, and GRB's would be sending their Gamma Rays through the casual horizon, stretched to the Micro Wave, at an average temp of 2.7K.

  12. #12
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    Quote Originally Posted by RussT
    There is another alternative that I can show, but I can't because of this...


    You have already made up your mind.
    No, he hasn't. What you need to do is to show how your model matches observations and makes predictions better than the mainstream models. Not only with words, but also including the math. This you haven't done, which mean your model isn't as good as the mainstream models. Why is it a suprise that we've rejected it?


    Quote Originally Posted by RussT
    Here is some brutal honesty, but sincerely said with ALL DUE RESPECT, you and most of the mainstream scientists on Baut have tried to convince 'us', that you are open minded and have not come to any conclusions, but these two quotes above certainly don't back that up.
    They certainly do. What he is saying is current mainstream model do a pretty good job of matching observations. Where they don't, there is a lot of research going on. The models you (and a lot of other ATM posters) propose, don't do as good of a job (or flat out don't work when the math is considered) discribing all the observations.

    The problem come from those posters who don't have the physics or mathematical background, who take word pictures, taken from a treatment meant for the general public, then stretch those analogies to the breaking point and beyond. Never realizing that what they are proposing doesn't work, because they don't know or understand what the theory is actually about.


    Quote Originally Posted by RussT
    There is too much to respond to above, so I'll just make my point of this thread here.

    If mainstream wants to answer...
    How SMBH's are made using GR
    Here and here

    Quote Originally Posted by RussT
    How galaxies are formed and evolve using GR
    here


    Quote Originally Posted by RussT
    How GR and QFT can be unified
    Don't know yet. There is much active research in String theory and QLG.

    Quote Originally Posted by RussT
    How String/"M" theory can fit this unification
    If string theory works, it will unify gravity and QFT. It won't just fit.

    Quote Originally Posted by RussT
    DM/DE
    Again, much research is going on with both of these.

    Quote Originally Posted by RussT
    Then the only way this can be done, is by having an open and honest discussion about the differences between the proposed Friedmann Naked Singularity and the Singularity that exists in the SMBH's!
    Ok, as soon as you have the mathematical background, we can discuss the equations relating to both of these. Until then, a discussion based on word pictures from second and third hand sources is not an honest discussion.

    Quote Originally Posted by RussT
    I am say right here, loud and clear, that just because the Big Bang Singualrity could not be made to work for the beginning of the universe, DOES NOT PUT IT IN THE SAME CATEGORY AS THE SINGULARITY IN THE SMBH"S!!!
    Will you stop treating singularities as some sort of object. They are not, they are simply the place where the equations don't work.

    Quote Originally Posted by RussT
    And just saying that we cannot observe the inside of a black whole is a huge mistake, and I can show why, now using GR rather than "M" theory, like I was before!
    Please do. No words please, just the equations.

    Quote Originally Posted by RussT
    But alas, most, like Spaceman Spiff, just want to make a few explanations (dismissals and denials), and just go on believing in the magic of the CMBR.
    He (and a lot of others here) have tried to explain it to you. Those dismissal and denial are a rejection of your ideas, because he understands the theory. I'm just a amatuer, who has bothered to learn the math and the theories from somewhere other than a popular science treatement. If even I can see the problems and misconceptions of your ideas, the professionals surely can. The people here are more than willing to help you understand what is going on, but you really need to meet them halfway. It takes a lot of study and hard work to make sense of these theories, due in part to the mathematics required. Why do you think a perusal of popular science websites and mixing of analogies, while ignoring the math, is somehow more qualified then a professional who has studied the theory (including the math) for years?

    Quote Originally Posted by RussT
    Actually, it's not radical at all...do you know of anyone who doesn't believe there are galaxies beyond 13.7 billion light years? So, all it would take, is for the universe to be 16 or 18 billion years old, and all those Quasars, Blazars, AGN, and GRB's would be sending their Gamma Rays through the casual horizon, stretched to the Micro Wave, at an average temp of 2.7K.
    There is so much wrong with this paragraph, it isn't even funny. RussT, have you even read the Ned Wright's site on cosmology? It's been pointed out to you before. This is what I meant by meeting us halfway. We've given you a site to learn from, and it doesn't even appear that you have bothered to take the time to actually read it.

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    Quote Originally Posted by RussT
    But alas, most, like Spaceman Spiff, just want to make a few explanations (dismissals and denials), and just go on believing in the magic of the CMBR.
    The CMBR is nothing of the kind. It is data, and one that is a prime prediction of the BBT.
    Nothing personal, RussT, but this sort of thing (and some others as noted by Nereid and Tensor), is a real turn-off.

    Very simply - astronomers work with the BBT because it is *currently* the most successful organizing principle that explains the vast array of independent data, and within its boundaries is consistent with everything else we know about. I wouldn't characterize it as a mature theory of nature, but as scientists (in particular, astronomers) we don't work in a vacuum and we certainly aren't in the business of making stuff up.

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    Will you stop treating singularities as some sort of object. They are not, they are simply the place where the equations don't work.
    Glad someone finally made that statement. Theories don't predict singularities, they are the bits where a theory cannot predict!

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    There seem to be two issues that RussT is "harping" on, because he hasn't had a satisfying response to. I'm not quite sure what he is concluding from this, but the issues are 1) why do astronomers think there was a hot dense phase early in the universe, and 2) what are the differences between the Big Bang singularity and a black hole singularity. The answer to the first is twofold; 1) a hot dense early phase explains the composition of the universe, and 2) it arises naturally from an extrapolation of observed physics backward in time. What more is there to say RussT? Note that "hot" does not equate with "singularity", the latter implies infinitely hot. You mention TeV energies-- that ain't infinite, so what's your point? The issue you seem to be brining up is, how far back can we carry that extrapolation? The answer is simple-- as far back as we have data to constrain the extrapolation. That's not very far back before the first few minutes, but it is natural to continue the extrapolation back as far as we still have physical theories to describe it. But even that extrapolation won't get you back to the "singularity". That has always been true, even before the CMB was observed. I really don't see why you distinguish the BBT "before" observing the CMB, and "after". The theory did not change, it merely had greater observational justification.

    The second answer is about the difference between the BBT singularity and a black hole singularity. The main difference is that the former lies in the past, and the latter in the future, of every world line that encounters them. So yes, they are different, but what is it that you are concluding from this? Neither type of singularity is observable, so neither really belongs in a physical description of the universe, but you can think of them as convenient "anchor points" for application of a particular theory. To take them any more seriously than that is to significantly misunderstand the role of theory in physics. How much do you expect from a mental conceptualization made by fairly intelligent hominid brains? The most fascinating thing about the BBT is that it is self-limiting, but that shouldn't surprise us-- we should think of all our knowledge that way.

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    Ken G, I'm very sorry, I thought this thread was done, so I missed this.

    Thank you or the well thought our explanation. You guy's are only seeing this from the perspective that you have chosen to assume is correct. To be very honest, I cannot figure out if this is just 'theory protecting', straight denial, or just years of thinking of something a certain way that there can be no other way.

    I will answer all of this in my next long post to Tensor in ATM>Singularity.

    Thanks

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    Quote Originally Posted by RussT
    You guy's are only seeing this from the perspective that you have chosen to assume is correct.
    You are asking this question in the mainstream part of the forum. You are going to get mainstream answers here. I think you got some very good mainstream answers. This is not a case of protection or denial. You are right to make any further pursuit of this in the ATM area.
    Forming opinions as we speak

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