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Was the formation of our galaxy inevitable

  1. Apr 4, 2003 #1


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    hi,was the formation of our galaxy inevitable after the BB or could there have been a different outcome, if the former is true then that implies that information or rules were stored pre BB, if the later is true what other outcome could arise.
    Last edited by a moderator: Feb 4, 2013
  2. jcsd
  3. Apr 4, 2003 #2


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    It is generally thought that the laws of universe were created at the exact moment of the BB. They arose of random chance. But once then, galaxies were pretty much inevitable.

    Of course, some other theories Eg. a certain theory involving changing values of c imply the idea that the laws of the universe change as time went on. But these are not quite accepted, at least yet.
  4. Apr 4, 2003 #3
    The Inevitable Universe?

    I believe that the Universe is a living, conscious Entity whose "life cycle" goes from one "Big Bang" through the next "Big Crunch" to the next "Big Bang" etc.

    I believe that there are natural forces of this Entity that carries over from one incarnation to the next, giving rise to similar "things" but that each incarnation creates a different "experience" via the inherent factor of randomness within the Entity's system.

    The Entity that is the Universe, however, can only BE the Entity that is the Universe. What else would It be?
  5. Apr 4, 2003 #4


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    Re: information

    Greetings !

    Welcome to PF wolram !
    I'm afraid your question is somewhat problematic.
    To make it slightly clearer, I could for example
    ask: "I threw a coin and I got one particular side,
    was it inevitable that this would happen ?"

    It depends on how you view the laws of the Universe.
    Are they deterministic or not. In the first case
    the answer is yes and in the second case it is no.

    Either way, why should it imply anything special ?
    What makes this particular result special and
    requiring "programming", while the other results
    are all "unspacial" ?

    Live long and prosper.
  6. Apr 4, 2003 #5


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    it seems that it is accepted that there had to be some sort of stored information pre BB for our universe to exist, given that energy was the precursor to the formation of our universe can anyone come up with an equation that would give the resultant effects
    i live in hope thankfully yours wolram
  7. Apr 4, 2003 #6


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    Isn't there a bit of a logical problem with something existing pre the creation of time itself?

    Personal theory: I would think that without a BB, the laws of physics would be undefined. Our current laws - conservation of mass/energy etc would not apply and literally any can happen, including the spontaneous uncaused appearance of the big bang.
  8. Apr 4, 2003 #7
    There may be a way of determining which "cycle" of universe we are in, by measuring the entropy it embodies. Stephen Hawking proved that a Big Crunch does not reverse time (i. e., entropy), but laws of physics may vanish (or rearrange completely) at a singularity.

    Galaxies are thought to be part of a cosmological fine-tuning at the Big Bang which requires certain initial parameters to differ by no more than one part in 1050 to obtain our current "exactly" flat macroscopic spacetime. (So a small change at the Origin might mean a tremendous change in the structure of the cosmos.) Inflationary theory attempts to address this and other anomalies of universal expansion.
  9. Apr 4, 2003 #8
    The Pre-Time Universe?

    If you can -- for one moment -- think of the Universe as a living Entity that expands from a so-called Big Bang into a very expansive Everything That Is, Has Been and Will Be...then, through natural forces, contracts (again) into a singularity which, in turn, bursts forth into a new incarnation...

    ...you might then see that even when Everything That Is is momentarily a singularity, it is still "only" Everything That Is.

    The Universe (in my view) is an Eternal Entity of Energy whose "life cycle" is described (in brief) above.

    If "Time" does exist, it exists from incarnation to incarnation of the Universe...not just in the one we're IN.
  10. Apr 5, 2003 #9


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    Hmm... Isn't the big crunch model out of favour after the red shift evidence suggesting the expansion of the universe is actually speeding up?
  11. Apr 5, 2003 #10
    Out of Favor?

    I favor it.
  12. Apr 5, 2003 #11
    The Big Crunch has been quashed.
  13. Apr 5, 2003 #12
    Science is Transient

    It'll be back.
  14. Apr 6, 2003 #13


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  15. Apr 6, 2003 #14

    Please don't use the word "conclusive"...and I think you know why.


    Haven't OTHER "things" accellerated and then slowed down?

    Haven't OTHER "things" expanded and then contracted?

    ...and so might the Universe...especially if there is "something" relentless and irresistable pulling it back.

    I've got my ideas about what that something might be...but I have NO CONCLUSIONS.

    Nor, I believe, does the Universe have a "conclusion"... not if It's the Eternal Entity of Energy -- which expands and contracts in each "lifetime" -- that I THINK it is.
  16. Apr 6, 2003 #15


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    I suppose it's legal when I use the qualifier "seems" is it not?

    Other things have accelerated and then slowed down. But other things have also accelerated and kept on accelerating... I don't think you can apply that kinda of equivalence here. All we know clearly is that the universe is accelerating right now, and there is no indication that it will stop. Hence it is probable as an idea that the universe would never come to a big crunch, until we see evidence otherwise.

    The most likely scenario based on evidence we can see is that the big crunch will not happen. We may yet make another discovery yet, but that's what it looks like at present.
  17. Apr 6, 2003 #16
    Perpetual Notion

    Actually, are you SURE that there are "things" that kept on accellerating? Name one, please.
  18. Apr 6, 2003 #17


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    Re: Perpetual Notion

    Planets in orbit are in a constant state of acceleration. Also remember that an acceleration and a deceleration are mathematically the same thing.

    M. Gaspar, you seem to have a decent picture of how you WANT the universe to be, but the evidence currently suggests otherwise. Could our theories be flawed? Certainly. But the evidence doesn't lend itself to theories that are radically different from the existing ones.

    Have you read Stephen Hawkings' "A Brief History of Time"? Its a good starting point for understanding many of the concepts we are discussing here. I highly recommend it and I think you would enjoy it.
    Last edited: Apr 6, 2003
  19. Apr 6, 2003 #18
    There is an outward cosmological acceleration - attributed to an Einstein-like cosmological constant or "quintessence" (themselves dependent on a "scalar field") - confirmed partially by standard-candle supernovae measurements. The scalar field (of constant, or "scalar" value over spacetime) is theorized to rest upon the energy of the omnipresent virtual vacuum. Certain supernovae, by virtue of their unique luminosity profile, provide "standard candles" for observing high-redshift accelerative deviations from the linear "Hubble law." At this time cosmologists conclude that the universe will continue to increasingly quicken beyond its current radius.
  20. Apr 6, 2003 #19
    Thanks for the lead...

    Are you saying that the Earth is orbitting around the sun FASTER now than it did, say, a billion years ago? And how fast will it be going just before the sun blows up? Of course, AFTER the sun blows up there will be no Earth, hence, no acceleration. My point? It's always something!

    Meanwhile, as was pointed out to me earlier, I have "speculations"-- not "theories" -- which seem plausable to me whether or not they fly in the face of CURRENT "evidence."

    I am simply taking the case that the Universe is a living, conscious Entity and seeing how far I can get -- conversationally -- before smacking my head into the brick wall of mechanistic thinking.

    Ouch. That hurt.

    P.S. I will read the book to see why I am so fundamentally WRONG. But feel free to tell me in specifics, if you wish.
  21. Apr 6, 2003 #20
    With all due respect...

    ...and I mean that sincerely,

    Scientists have changed their minds before. Like I said, 'Its always something" and I guess I like to believe that they will discover a something that will cause the Universe to eventually collapse.

    And WHY do I "like to believe" this? Because I like to believe that the Universe is a living, conscious Eternal Entity of Energy that has infinite incarnations from "Big Bang" through "Big Crunch" to next "Big Bang".

    Maybe it's not so. But if, at some point in your lifetime, "evidence" suggests to your colleagues that the Universe WILL "implode", please remember that there was someone who got there first.

    Meanwhile, I believe there is a way you can "IGNORE" me.
  22. Apr 7, 2003 #21


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    Re: Thanks for the lead...

    No, he's saying that gravity is an acceleration force (meters per second PER SECOND). Gravity is accelerating the Earth toward the sun, but this is counter-balanced by the Earth's tangential velocity. The result is a stable orbit.

    aside: The sun is not going to blow up like a supernova...but it will go into a "red giant" phase.

    Point taken. Energy within spacetime winds down. But what about spacetime itself? Current observation is that its expansion is accelerating and there does not seem to be anything capable of slowing it down. Maybe there is, but we don't see it yet.

    Fine. But why the contempt for current evidence?

    No book out there will prove that the universe is not a living, conscious entity. But, by the same token, no book can prove that is true either. It's a nice idea, but what evidence is there that it's reality?
  23. Apr 7, 2003 #22


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    Re: With all due respect...

    Again, ok, scientific theories can change when new evidence is obtained. Cosmology in particular is an aspect of science with a lot of uncertainty. I encourage you to study cosmology, find the evidence, and develop the explanatory model. The Big Crunch and the Cyclic Universe ideas are not off the scientific table completely at this point. We're just pointing out that the current evidence better supports a different idea (eternal expansion). The Eternal Entity of Energy idea is not part of any scientific model though (more of a religious belief).

    As far as I can tell, this conversation is still polite. No need to take any offense. If you're not open to discussing your ideas, then don't post them.
  24. Apr 7, 2003 #23


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    re expantion

    the big crunch is i think a theory for eternalists, the thing that bothers me about continuous expantion is that it is a total loss system. the theory is that space was created by the bb, dosent that mean that a second bb cannot occuer in our pre existing space?
    regards wolram.
  25. Apr 7, 2003 #24
    Re: With all due respect...

    Scientists don't change their mind without evidence. If they find reproducable evidence that their theory is flawed, they try to change it so that it matches all reproducable observations. They don't change their mind because something "sounds good" or because they "would like to believe".

    Current evidence suggests that the universe will continue to expand indefinitely, but that is by no means a "fact" yet. There is still room for more debate and experimentation.
  26. Apr 7, 2003 #25
    Don't know where to begin...

    I never said scientists change their minds without evidence.

    I never said I don't respect scientists. In fact, I revere them.

    My inviting Loren Booda to ignore me was for HER benefit, not mine. I was NOT feeling "offended" but hopelessly OUTCLASSED (as perhaps I am by MOST of you...left-brain-wise).

    A "red giant" could be called an explosion in slow motion.

    Noone has yet offered an example of increasing accelleration that NEVER STOPS. And, PHOBOS, it's the counter-balancing I'm "counting on" with regard to a "pulsating" Universe.

    And I'll be doing some reading to shore-up or alter my views.
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