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Creational Theory

  1. Oct 6, 2003 #1
    "Creational Theory"

    Betty here.
    This will be a first attempt at posting.
    This ideology was moved here from "Debunking Religion."
    I subscribe to the Inflationary Theory of which,"I Believe" there are about three theorys that meet these requirments with similar results. "Our universe."
    I'm no whiz here so many of you will use terminologys I may need to have simplified. Many of you know me already.
    "Debunking Religion" came to a screeching halt because so much happened leading up to the point where "I Believe" we shed the energy of the Higg's Field(which i could use a lot of help in comprehinding if one of you will be so kind) and left "False Vacume" when the energy coverted to mass, Henceforth the Big Bang.
    As far as I can assertain (as the bible is open to interpretation) the big bang would be refered to as the moment of creation.
    Now, back to the beginning.
    Think "NOTHING", absoultly nothing. Even a vacume needs containment of some sort or the vacume would not work. This is not even a vacume. It's just nothing. Now thats deep.
    If your not into this, lets discuss "how come?"
    If you are, or think you may be then help me with this.
    What can happen in the world of quantum physics can happen in the first few milliseconds to throw off the balance off nothing?
    I think "Nothing" is an UNSTABLE system. Law states that "all systems must evolve to a lowest state of energy" which is why in about several trillion years everything should be black.
    Please rethink what "truely" nothing must be. It's conceptually difficult.
    L8R
     
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  3. Oct 6, 2003 #2

    Nereid

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    Could you clarify what you are interested in a bit please? You seem to have a number of things rather confusingly (to me anyway) thrown together - Higgs fields, false vacuum, the Big Bang, and unstable energy systems.

    If I could ask about just one specific thing, a millisecond is an awfully long time; light will have travelled 300 km in that time, and if your PC had a clock speed that slow you'd never get your post sent. Do you have a particular reason for selecting such a long period of time?

    If you're interested in the early universe, you might find this article of interest:
    http://arxiv.org/abs/astro-ph/0305179
     
    Last edited: Oct 6, 2003
  4. Oct 6, 2003 #3

    chroot

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    I hope you realize the religion forum was killed for a reason.

    I'm also not sure why you seem to have beliefs about what the Higgs (not Higg's) Field does and does not do, when you don't even know what it is.

    That sort of thing seems to be a hallmark of the crackpot.

    - Warren
     
  5. Oct 6, 2003 #4
    :wink:Hey, thanks for showing some intrest. I'm still in need of some help in a few areas. Thats why I'm here.
    CHROOT, help me here. This a weak point for me, I've only some loose concept of the charicteristics of this field. Am I correct that matter was created as this energy field was dissipating?
    I wait for an answer on that one. Perhaps I have my sequence of events out of order.
    NEREID well, I guess, as I've started things, the first problem I'd like to tackle is the Quantum Fluction or Singularity that may have been the first thing to occure that sparked the build-up of runaway energy. Depending on which way one leans on this ideology there are two or three accepted possibilities.
    A millisecond "is" a long time in the context we're concerned with, and many things are happening here simultainiously.
    We'd have to go back to the 500,000yr mark to see atoms form; back to the 3min. mark to watch the formation of nuculi, but before the .oo1/sec. mark, as far as i know, all matter was in a plasma state with free electrons, protons and nuculi. Is that correct?
    It is before this point I want to start.
    I read some ideas that seem to imply that "nothing" is "something" as zero "is" a value, and some other books that use quantum fluctions as their springboard to explain "matter."
    So, where did we get matter from energy and what started the build-up of energy to start with? Keep in mind I'd like to start with nothing, an absolute void.
    As I said,I need some help on conceptual visualzation on what or how the Higg's Field influences energys during it's phase.
    It's a difficult field to find info on that I haven't read yet.
     
  6. Oct 6, 2003 #5

    chroot

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    I can tell from your questions that you are not even remotely close to having the physical skills to be able to understand the nature of the early universe. I honestly hate to say this, but I feel I must: start slow. Go read up on basic particle physics, and about the four fundamental interactions. Only when you fully understand that material will you really be able to understand anything about the early universe.

    - Warren
     
  7. Oct 7, 2003 #6
    Betty ------ Ignore chroot :-)

    If he does'nt have the answer ... he tells you about how stupid you are. It's essentially --- His trademark.

    Fact is ..... Nobody has an answer to your questions. You are on close to the same footing as any physicist. Anything that pops into your head could very well be the answer to your question.


    Perhaps starting with nothing in the absolute sense is yer first mistake. Perhaps this is not possible by any means whatsoever. As for the Higgs field (particle) - Maybe they are on to something, or maybe you should make something on yer own. That's what they do. They come up with an idea and see how it plays out. Figure it out for yourself - Call it the (slapenduula crunch mondoo).

    If you can think in a purely logical manner (difficult to do by any man, woman, or child) The answer will logically come to you. And don't leave out the possibility that the universe began in an illogical manner either - Logic should tell you this is a possibility also.

    Above all - Ignore Chroot

    He has an agenda to destroy yer discussion. He quite literally can't help himself.
     
  8. Oct 7, 2003 #7

    Nereid

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    Thanks for the clarification Betty.

    May I suggest the following?
    If you're interested in the nature of the vacuum, quantum fluctuations, virtual particles, etc, then your thread is in the right place - Quantum Physics. Chroot made a very good suggestion - find a good introductory book on quantum mechanics (or an online course) and take the time to learn the concepts, if not the math.

    If you're interested in cosmology - the origin of the universe, etc, as teased out by the application of the scientific method - then start with a popular account such as Steven Weinberg's The First Three Minutes. Your questions would be better posted to the General Astronomy area.

    AFAIK, physics is mute about the first 10-43 seconds of the universe, so a discussion about this period will be largely speculation.

    If you're trying to introduce a religious character to this forum, as you'll have seen if you read through the various posts, this thread will be moved by the Mentor to a more appropriate area.
    The era which interests you - the first millisecond - includes inflation, and the time when the strengths of the strong, weak, and electromagnetic forces diverged. The physics of the last part of the millisecond is well described by the Standard Model; Gordon Kane's article in the June edition of Scientific American ("The Dawn of Physics Beyond the Standard Model") is a good overview.

    If you've questions on the Lineweaver article (linked in my previous post; it's a good summary of 'quantum cosmology'), there are already a couple of threads going on that.
     
  9. Oct 7, 2003 #8

    marcus

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    Nereid, that link you posted when you said

    "If you're interested in the early universe, you might find this article of interest:
    http://arxiv.org/abs/astro-ph/0305179
    ..."

    is to one of my most favorite articles about the universe of all time
    Lineweaver's "Inflation and the Cosmic Microwave Background"
    and I hope Betty has a look at it----if only to photograph a mental image of the teardrop-shape lightcones---it has such clear informative spacetime diagrams I wish everybody could study them a bit---theres stuff in that article that is not really hard!


    However there is a potential for confusion in language in what you say. "Quantum Cosmology" for a lot of people means where you quantize a going model of the universe---not necessarily or even primarily focussing on the first picosecond or nanosecond or minute when presumably quantum physics was so important---but actually trying for a quantum model of all space and time.

    Maybe that is an unwise endeavor :smile: tho personally I dont think so. And maybe it is an awkward use of words. But it is how a considerable number of people talk. So when Martin Bojowald says "Loop Quantum Cosmology" he means quantizing the prevailing cosmologists model---General Relativity and specifically the Friedmann equations----by (in his case) loop methods---and then applying this quantized model to questions in cosmology.

    so for him and a number of others "Loop Quantum Cosmology" means Loop Quantum Gravity as appled to cosmology.

    So it doesnt immediately have the sense of focussing on the very early universe----although because that's interesting it often does turn out to focus on that!

    I would say that Lineweaver's article is about the early universe (and also about events far into the future, with accelerating expansion!) but that the cosmology in it is mostly classical GR, not quantum. just clarifying a difference in terms
     
  10. Oct 7, 2003 #9

    marcus

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    BTW isnt it wonderful how theological speculations always filter into cosmology and indeed astronomy in general?

    Nereid you very feelingly brought up the Fermi question "where are they" which has sometimes given me a scary supernatural tingle----because there ought to be lots of trash and at least archeological evidence unless ALL the aliens were compulsively neat people

    Anyway I come down on the side of welcoming Betty to cosmology with the utmost politeness since one never knows who was around at time zero

    But I want her to understand the use of Occam's razor. Thats all. Thats all I ask for my part (and Im just one voice in the discussion).

    Assuming that the universe began at the same moment expansion began---call it time zero---is probably an unnecessary complication to the picture since it is no longer required by theory.

    It used to be required that when you extrapolate backwards you stop, because the mathematical model broke at time zero---with infinities. It went haywire and wouldnt compute because of density and curvature blew up.

    So people thought of the Universe as beginning at time zero and talked like that to newspaper reporters.

    But now that trouble seems to have been fixed and there is no longer any reason to suppose that the cosmos began at time zero. It MAY have begun then. But adding that sort of complicates things unnecessarily in a way that Brother Occam would not like.

    One can believe that it began at time zero as a matter of Faith and lots of people do. But I dont see any scientific reason to include a timezero Beginning in the actual model.

    Eventually maybe the smell of singularity that used to attract theologically minded people to time zero and the big bang will probably go away because the singularity has been or is in the process of being erased and the timeline extended out into negative time. So then we are back to Eternity and theological thinking can regroup around that.

    Does anyone know the Latin phrase "Pleni sunt coeli et terra gloria tua" and can anyone but a fool really argue with that. The only question is who tua is and nobody really knows do they. I think she's' a girl and her name is Nature and Im also a total sceptic about speculations like that and yesterday my choral group rehearsed a dynamite sing by Josef Haydn called "The Creation". So we're complex what else is new.
     
  11. Oct 7, 2003 #10

    chroot

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    In fact, I can explain in painstaking detail the currently accepted theory of the early universe, and the Higgs field, and so on. Another fact is that if I did, she wouldn't understand a word of it.
    You're just bitter because I've called you stupid, too.

    - Warren
     
  12. Oct 7, 2003 #11

    Nereid

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    It can be confusing, can't it. However, in this case, I simply borrowed the phrase from Lineweaver. In the penultimate section of his paper he says:
    BTW, to what extent would a successful LQG or SST (SMT?) be able to address at least some part of the first 10-34s?
     
  13. Oct 7, 2003 #12
    Well, ARC-CENTRAL, Thank you for some encourgement. I did state to all that I'm certainly no whiz here; no real schooling, but with great intrest and the gift to understand abstract ideas and concepts. I haven't read most of the books and stuff you all discuss.

    CHROOT, Thanks for an answer anyway, but stick around, I think this might be an extensive thread if I don't stupid out on all of you.

    NEREID, Mabey it is gen astron I should be at, "but" If my questions hinge on 10-43sec. and before then isn't "everything" theory, speculation or conjecture? And if so do the rules of "general astron & phys apply here?, or I'm I wrong in thinking that this period was influenced solely by quantum physics. I'm refering to a point when everyting was energy. I'm of the theory that there was a runaway build-up of energy, but I'm still trying to invision these "Virtual Particles" theorys. Wouldn't these particles constaintly get "created and annililated" in a span too short to measure "balance the emtiness or vacume?" And what about the uncertainty princple? Sooner or later some particle is not going to get annililated or reabsorbed, if you will, in time. Now things are out of balance. What happens?
    I'll read the books and links left for me.
    Marcus; Thanks for the support.
    WHAT- - the hell is OCCAM'S RAZOR? I'll look that one up.
    CHROOT; I've been saving this for last. You may be suprised
    To know that I am A longhair bass guiter player with a wife 4 kids(still at home) and I'm 48 years old and can play STAIND, NICKLEBACK, GODSMACK, or THEORY OF A DEADMAN better than anyone you've met in a while.
    Thanks to all. I've got some reading to do.
     
  14. Oct 7, 2003 #13

    chroot

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    You may be surprised to know that I also play guitar and am not really impressed by a bassist playing Staind -- how much more plain and poppy can you get? If you want to impress me, come back when you can keep up with Wooten.

    - Warren
     
  15. Oct 7, 2003 #14
    Hello Chroot, I see you should be qualified to speak on these matters at hand. You seem displeased with my lack of knowledge in some areas. It would be helpful if you weren't so condisending and criticle and could perhaps offer some usefull guidance.
    I've already read up on things suggested to me by others and have learned much already.
    I would think that you can play guitar quite well because of your other endevours in life. However I would never assume that you could only play three songs or songs of only three bands. So your attack on my choice of music seems confusing. I will only offer you comments when you specificly ask if that is what you prefer. If you can chill just a bit I'd like your input here when it's relevent. If we could, I'd like to jam with ya but your a long way from the crib.

    NOW, Marcus, Hey, I read that stuff on occam's razor. That's great theory to be considered. It helps me.
    There should be no more assumtions than necessary: I.E. simplicity.
    The 2nd paragraph was good.
    Would not a state of "Supersymmetry" be the ultimate in simplicity, like before the four forces were defined?
    This seems good, now from here back. What may have brought all this energy into creation? Were the four forces defined as mass was created? And where can I learn more on the Higg's Field?
    L8R - - - - - - - - - - you too chroot.
     
  16. Oct 7, 2003 #15
    I dont think Quantum Mechanics is the best way to start off period, most physicists don't understand it!
     
  17. Oct 7, 2003 #16
    :wink:Well Jeebus, are you sure bout that? I don't think I can get the answers any other way. Mabey you will help.
    I've been reading.
    In 1971 somebody(i can go back and find it) did the math and found the Higg's Theory a very real possibility.
    As I read things I find the belief is the Higg's field has "Magnitude" but no general/particuler direction in space. I understand some think remnants are "Still" there. I previously thought the fields energy disapated. So I'm making progress.
    I see now how intiger(did i spell that right) is important, I think.
    "IF"- a spin 1/2 particle is rotated 360' it will be in a measurably different location than maco logic predicts. A 720' rotation is required to return it to it's starting point. Who can verify that?
    I saw several other ideas while reading. General consensus seems that the next generation of accelerators will help.
    I'll read how the boson acts with the field to create mass and get back here.
    These bits of info seem to fall together as I learn more specific detais of each process going on.
    L8R
     
  18. Oct 7, 2003 #17

    selfAdjoint

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    It's almost right.

    A spin 1/2 is measured by a "spinor", which is almost like a vector. It is a pair of complex numbers (in Dirac theory and QFT it's four complex numbers). When you rotate the particle, the two numbers start to change, in a correlated way, and when you have turned the particle trough one full turn it may look as if it has returned to the same state but its spinor numbers are not back to battery. You have to turn the particle through another full turn (as you said), to bring them back to their starting values.

    You may say, oh, that's just some numbers, but this spinor measures the spin of the fermion (a fermion is a particle with quantum spin 1/2), just as the number on the scale measures my weight. If I want to change the number I have to change my behavior (diet and excercise). Just so the spinor controls a lot of the behavior of the particle.
     
  19. Oct 8, 2003 #18

    Nereid

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    From Planck time to the CMB would certainly be cosmology, and it would take a great deal from high energy physics, the Standard Model, supersymmetry, LQG, superstring theory, SMT (what DOES it stand for?), and so on. If you're seaching for answers about what happened in the first 10-43 seconds (or what happens at 'temperatures' greater than 1030+ K), I leave it to the PF old-timers, especially marcus and selfAdjoint, to suggest how best to proceed.
     
  20. Oct 8, 2003 #19
    SelfAdjoint, Man, that's cool insight you passed on.
    Thank you too Nereid, I'll digest what I've learned since last night.
    L8R
     
  21. Oct 8, 2003 #20
    Hey, I'm back. It's sunney and warm here tody.
    No wonder this is stuff is theory, crap, who could possibly assemilate"so" much information.
    I gotta hand it to some of you, Today I've been reading a lot. I've copied and pasted several highlighted words from your input and my brain hurts[b(].
    I have read on Dirac Theory, Tensors, Einstein's Summation and a page on Arther Cayley (1821-1895) as well as many other definitions.
    I may be a day or two on returning as I'm going to learn more in order to put forth some questions or thoughts that might be slightly above high school level.
    "Assuming that the universe began at the same moment expansion began---call it time zero---is probably an unnecessary complication to the picture since it is no longer required by theory."
    This was an important statement by one of you(i thought anyway)because it allowes for "minus infinity."
    If early on the universe "was" "Just A Vacume" it seems there would still be some kind of balancing act going on between "Virtual" particles of some nature as they would be created and annililated constantly by an equle number of particles, being particle and anti-particles, causing disruptions in the cosmic sheet.
    Is it too much to postulate that this went on forever, or an unmeasuable, or "Infinit" amount of time untill the uncertainty principle happens along and "SOME" particle somewhere doesn't get annililated in time.
    What might theory say would happen? Would "this" spirel out of control and start some imbalence that "MIGHT" throw us into a big bang? If the bang point is ZERO then we have minus infinity and plus infinity finally in the same equation, "IF", we keep expanding untill everything is cold and dead.
    O.K., I'm getting in too deep, I'll stop for now.
    L8R, and thanks much for your input SelfAdjoint and Nereid.
    I'm quite intruigued at this level.
    Any sites that help would be good.
     
  22. Oct 12, 2003 #21
    from nothing to nothing

    Hi,

    As you said logically the universe must have started from a point of nothing however the problrm with this is the word "started"

    The essense of nothing to something is init self a false premise in that nothing co-exists only with something....more logic ....

    PLease feel free to read an extract that I have at my web site on this subject. on "creational nothingness" the nature of time and nothing.

    http://au.geocities.com/scotts1959 [Broken]

    I look forward to your comments
     
    Last edited by a moderator: May 1, 2017
  23. Oct 12, 2003 #22
    interesting but I don't like the notion of nothing.
    Even those intangeable nothings contain energy (like empty space).
    so you agree that light is not a constant.
    How do you suppose that it could have been faster in the past than it is today (I read an article on this several months back on quickfound.net/scitech, lots of good physics news on there)?
    How do you suppose, that time exists then? What created time?
    What is the purpose of time in the abscence of energy, does it still exist?
    If time is dependent on energy, what are the properties of energy that time is dependent on (perhaps time is event driven)?
    I wrote a little bit on my thoughts of time in a post, I did it quick and tried to draw from as many examples as I could think of,
    clearly if we took the approach that time is event driven it would make a good deal more sense (wouldn't it?) and would also put some nice caps on the cosmic speed limit (because increased levels of interaction would slow time down for a particular object, resulting in even the most powerful engine decreasing in efficiency because it would stretch out that acceleration (the energy producing it) over a larger period of time, causing your vessel to require an infinite amount of energy to reach the speed of light).
    This is the effect I call temporal entrophy.
    There indeed are things that travel faster than light, they are the constituents of gauge fields, and these fields impose the speed limit on light.
    It would be interesting to see how precise one would need to measure the speed of light to show that even an object travelling at the speed of light undergoes time, it simply does not stop (and then run backwards if you exceed the speed of light).
    In such a universe it would be impossible to go back in time, and in this universe I propose that it is impossible to go back.
    It is possible to go really far in time by slowing your time down by increasing your velocity, or it is possible to experience your life in the blink of an eye, by reducing your velocity (but there would be a cap as to how fast time could go relative to the earth given these gauge fields are in constant motion that regulate time).
    There is nothing that really explains how entanglement seems to defy the laws of time, how one could send a message faster than the speed of light with it (unless if time were only a by-product of interaction and entanglement were a state native to everything in the universe but on such a vast scale that things appear to have a duality about them).
     
  24. Oct 12, 2003 #23

    chroot

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    Nothing 'contains' energy. You are free to select your 'zero' energy anywhere you'd like, and the physics doesn't change. I can quite easily define the energy contained in the vacuum to be exactly zero.
    This is fishwrap nonsense. All such attempts to show the supposed 'c-decay' have involved the researcher cherry-picking observations in support of his hypothesis. In at least one case I've seen, the researcher committed deep intellectual dishonesty and actually reported an erroneous datum specifically to make it agree with his hypothesis.

    Modern physics does not support c-decay, nor any mechanism that might support it. There is no experimental evidence that shows it happens, and a great deal of theoretical work that shows it cannot.
    What created truth? What created beauty? What created the thing that created truth and beauty? This not physics, it is philosophy.
    Time does not slow down for any object. On the bridge of a starship moving at 0.999c with respect to the earth, everything will look exactly, 100%, normal. The only people who measure "time slowing down" on the ship are those folks back on earth. Time does not slow down in the starship -- time dilation is simply a result of the difference between the reference frames of two distinct observers.
    According to the captain of the starship, there is no speed limit. He can accelerate forever, firing his thrusters at some particular thrust, and measuring the same acceleration on his instruments -- forever. He can measure his own speed as approaching infinite. He can bounce between stars in milliseconds according to his own watch. However, the people back on earth will disagree, and say that his clock is just running very slow, and his starship is moving at nearly the speed of light. The point of this discussion is to bear out one particular feature of relativity that your pop-science crap books seem to have missed:

    There are no relativistic effects until you compare the observations of two distinct observers.

    When there's only one observer, that observer will never notice anything different inside his spaceship. Only by looking outside will he see anything he would call "relativistic."
    Once again, I strongly urge you to actually learn relativity before making up your own senseless terms to describe effects that don't really happen.
    This is indeed wrong. The quanta of fields move with a group velocity that is always less than c.
    An object travelling at the speed of light experiences zero proper time between any two events in spacetime. It follows a null geodesic. You are incorrect.
    My velocity relative my chair is approximately zero right now. Does this mean I am "going really far in time?" What the hell does that even mean?
    Like I said, my velocity is approximately zero with respect to my chair, but lo and behold, I see nothing awry going on. My wristwatch seems to be ticking along just fine.
    YOU CANNOT SEND INFORMATION FASTER THAN LIGHT WITH QUANTUM ENTANGLEMENT. THERE IS NO ROOM TO DEBATE THIS. I suggest you actually go read up on your proposals before posting them for our disection.

    - Warren
     
  25. Oct 13, 2003 #24

    marcus

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    I assumed bettysfetish was female and he says to chroot:

    "You may be suprised
    To know that I am A longhair bass guiter player with a wife 4 kids(still at home) and I'm 48 years old and can play STAIND, NICKLEBACK, GODSMACK, or THEORY OF A DEADMAN better than anyone you've met in a while."

    so now that little misunderstanding is cleared up.

    Earlier in the thread (October 7) Nereid asked:
    -------------
    BTW, to what extent would a successful LQG...be able to address at least some part of the first 10-34s?
    -------------

    Nereid, part of your question you asked gets over into how LQC deals with the universe right around timezero. It predicts inflation (you dont have to put inflation in "by hand") and it removes the singularity.

    There'v been a bunch of papers by a bunch of different people that you can get from arxiv by search with keywords like

    loop quantum cosmology

    inflation loop quantum gravity

    To save the trouble of searching and choosing which articles to read, here are a couple of September ones:

    Quantum Gravity and the Big Bang
    http://arxiv.org/0309478 [Broken]

    Quantum Gravity and Inflation
    http://arxiv.org/0309045 [Broken]

    the meaning of time becomes an interesting question around timezero and whether one can ask about time-evolution in steps smaller than Planck time (0.539E-43 second)

    Loop cosmology is a radical simplification of the full theory of quantum gravity (Friedmann eqns of cosmology are much simpler than the Einstein eqns of the full GR theory). So its much easier to develop LQC and it has happened very quickly----now LQC can help guide solutions of the more difficult problems of the full LQG theory. This was reflected in the "conclusions" part of one of the papers

    "With new developments in quantum geometry, quantum gravity has become a theory whcih can make concrete predictions about the very early stages of the universe. Results include possible solutions of old conceptual problems, as the singularity problem and the problem of initial conditions and also new phenomenologicial proposals which can be confronted with cosmological observations. The models currently available are most likely too simple, but more complicated ones with less symmetries [ref] and more realistic matter content are being developed. An advantage of the formalism is that the relation between models and the full theory of loop quantum gravity is known, so that lessons learned for models can be taken over to the full theory. In this way we will be able to guide developments in quantum gravity by cosmological observations."

    There will be a talk on loop quantum cosmology by Bojowald at this month's "Strings meets Loops" symposium at the AEI, so this should give an even more timely summary of the state of research in that area.

    There was a stringy part to your question too but I cant respond to that part because I dont know of any concrete predictions that string theory makes---seem to be an infinite supply of versions of the theory all saying different things and no way to choose
     
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  26. Oct 13, 2003 #25

    marcus

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    from the horse's mouth about "creational theory"

    Bettysfetish raised the issue of what happened at timezero and
    Nereid asked what Loop Gravity has to say about it. The most informative short discussion of this is in Martin Bojowald's 6-page paper "Quantum Gravity and the Big Bang" and he's the person that has found out the most new stuff about this in the past 2 years. So here's a quote. The abstract and a few sentences from the beginning of the paper:

    -----------------------------------

    Abstract. Quantum gravity has matured over the last decade to a theory which can tell in a precise and explicit way how cosmological singularities of general relativity are removed. A branch of the universe “before” the classical big bang is obtained which is connected to ours by quantum evolution through a region around the singularity where the classical space-time dissolves. We discuss the basic mechanism as well as applications ranging to new phenomenological scenarios of the early universe expansion, such as an inflationary period.

    1 Introduction
    When the big bang is approached, the volume becomes smaller and smaller and one enters a regime of large energy densities. Classically, those conditions will become so severe that a singularity is reached; the theory simply breaks down. For a long time, the expectation has been that somewhere along the way quantum gravity takes over and introduces new effects, e.g. a discrete structure, which prevent the singularity to develop. This presumably happens at scales the size of the Planck length lP , i.e. when the universe has about a volume lP3.

    Since at the classical singularity space itself becomes singular and gravitational interactions are huge, such a quantum theory of gravity must be background independent and non-perturbative. A theory satisfying these conditions is in fact available in the form of loop quantum gravity/quantum geometry (see [1, 2] for reviews). One of its early successes was the derivation of discrete spectra of geometric operators like area and volume [3, 4, 5]. Thus, the spatial geometry is discrete in a precise sense. Furthermore, matter Hamiltonians exist as well-defined operators in the theory which implies that ultraviolet divergences are cured in the fundamental formulation [6, 7].

    Both properties must be expected to have important consequences for cosmology. The discreteness leads to a new basic formulation valid at small volume, and since gravity couples to the matter Hamiltonian, its source term is modified at small scales when the good ultraviolet behavior is taken into account. It is possible to introduce both effects into a cosmological model in a systematic way, which allows us to test the cosmological consequences of quantum gravity (reviewed in [8, 9])."
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    classical GR breaks down at time zero because of infinite density and curvature

    quantizing GR removes the singularity---when quantized the Friedmann equations go smoothly back in time, showing a bounce at time zero

    Bojowald was the first to get this result. the first time it came out was
    "Absence of a Singularity in Loop Quantum Cosmology"
    http://arxiv.org/gr-qc/0102069 [Broken]

    stringy approaches are perturbative and background-fixed but to directly deal with extreme density and curvature it helps, as Bojowald observes, to use a theory that is free of perturbation methods and background-independent. In fact to deal with timezero he says the theory "must be background-independent and non-perturbative"---which makes sense to me, dont know about you:wink:. So probably the answer to the stringy part of your question, Nereid, is limited by this consideration, but who can speak for what that theory (those theories) actually predict(s)?
     
    Last edited by a moderator: May 1, 2017
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