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Big Bang breaking the rules?

  1. Aug 9, 2011 #1
    I recent.y received a polite warning about a 'jumbled" post.

    I will try and restructure it.
    My problem is that I do not speak the same language you do. the numbers do not mean to me what they do to you.
    So I have to use terms or phrases that will convey my thoughts.

    In simplistic terms.
    the universe is in chaos. galaxy's are crisscrossing running in to each other and other phenomena.

    IF the universe stared as a singularity.
    1. there must be a "birth point"
    2. if so, then why are they rambunctious? (breaking the rack at pool) from the point of birth in all directions at once as the laws of physics dictate. (unless acted upon by an outside force) there is no reason for Andromeda to be on a collision course with the milky way.
    There are no side rails to bounce off of.

    Can someone help me understand why?
    (please use K.i.s.)
  2. jcsd
  3. Aug 9, 2011 #2
    The observable universe is not in chaos - it is in fact fairly homogenous with the CMBR being uniform to 1/1000.

    If there was a "birth" point, that would contradict the previous homogeneity I outlined. I suggest you look at the balloon analogy, limited as an analogy as it is I think it will provide you with a good basis. Essentially each matter dense region of spacetime that has since become a galaxy/cluster has not moved since the Big Bang, it is possible for expansion to occur without anything "moving". You must clearly differentiate between kinematic motion and "motion" from expansion. If we assume isotropy then geometrically the BB began everywhere at once, to ask where in our spacetime did our spacetime begin is sort of meaningless, almost like asking where in our reality did our reality start!

    The reason andromeda is heading to us is just due to gravity and nothing more - on a grand scale the Observable Universe is still homogoneous - andromeda is one of few exceptions and as I stated just due to the local force of gravity.

    Hope this helps.
  4. Aug 9, 2011 #3


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    Perhaps this will help.

    Imagine a fog of material which doesn't gravitate, has no energy, and no motion. You and I are inside the fog. We do not know where the edges of the fog are, or even if there are edges. As space expands the distance between the particles in the fog increases. NONE of the particles are moving, yet the distance between each one gets bigger. So over time the fog thins out. Can either of us say where the "birth point" is? No! There isn't one! ALL of the fog is expanding at all times! The particles far away from us move away faster than the ones near us.

    Now let us start over, but this time the particles in the fog move. So as space expands the AVERAGE distance between particles increases, yet we still have small clumps of particles that simply because of chance are grouped up. As the particles move the clumps form in different areas and then dissappear quickly. To you and I inside the fog, we cannot see these particles and to us it looks the same as it did before, just a fog.

    Again we start over but this time the particles move AND they are attracted to each other. So, as space expands in this scenario the average distance between particles is still increasing, yet the clumps tend to be permanent since the particles now attract each other. So over time you and I see small clumps appear and form bigger clumps over time. The distance between these clumps still increases though. In this scenario and the previous one, you and I would see a random direction for the motion of all particles. However, if we could look far into the distance we would see the far away particles having less and less speed toward us and more away from us. Even further away we would see that NONE of the particles are heading towards us and all seem to be heading away from us. In addition, you and I notice that over time the expansion seems to be increasing!

    The 3rd scenario is similar to the current universe. Our solar system is inside the Milky Way galaxy. Our galaxy has several neighbors that are attracted by our gravity. A little further away we see a big neighbor in the form of the Andromeda galaxy. Like our nearer smaller neighbors, Andromeda is also attracted to use. In addition we are attracted to it. Since we are so close to each other (on a universal scale) the force of our gravity is enough to overcome the expansion of spacetime.

    Further away we notice that our local group of galaxies is attracted as a whole to a "cluster" of other galaxy groups. This in turn is attracted to other clusters and forms a Supercluster. Beyond that we see many many other superclusters and notice that almost all of them are so far away that the expansion of spacetime is causing them to move AWAY from us. If we were able to cut away all the space between us, it is possible that a far away galaxy could be moving towards us relative to its local space, yet because of the expansion it will always be increasing in distance from us.
  5. Aug 10, 2011 #4


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    This is the source of your dilemma. There cannot be a 'birth point' unless the initial singularity was embedded in some pre-existing spacetime. Under GR, there was no pre-existing spacetime. For a good discussion see:
  6. Aug 11, 2011 #5
    So far I have been told that the galaxy's are not moving. it just looks that way because "like dots on a balloon".
    That the galaxy are not running into each other because the expansion of the space between them prevents it. Yet, we see galaxy's crashing in to each other. we see stars being torn apart by SMBH's because the star got to close. We even have evidence of 2 black hole's doing the dance of death.

    and that "there was one big bang at a focal point" and There is no focal point. the micro wave back ground noise is a matter of fiction.
    AND, all of the mass in the universe sprang out of every where at once.

    So now... I look around and have to ask.
    "so that means that the earth spins, tilts and is in a elliptical orbit around a star that is spinning around a galaxy that WAS shooting across the universe, but because of the expansion of the universe we (SOL) are actually sitting still.

    again i ask Keep It Simple.

    My base question. was based on the facts that there was a big bang. we have the echo of the noise to prove it. (dont take "noise" literally) THAT would mean there there is a focal point of the moment of creation.
  7. Aug 11, 2011 #6
    by your comment. there was no space or time before the existence of the big bang.
    isn't that like saying there was no world until you was born and opened your eyes?

    "The mathematics of GR state specifically and unambiguously that 3-dimensional space was created at the Big Bang itself, at 'Time Zero', along with everything else."

    is this not the same thing (ideology) as M theory and "membranes bumping?
  8. Aug 11, 2011 #7
  9. Aug 11, 2011 #8


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    There are several concepts in your post about which you express confusion. I think these FAQs in here is cosmology will will address your issues (except maybe your comment about numbers ... I didn't understand that)

    https://www.physicsforums.com/forumdisplay.php?f=206 [Broken]
    Last edited by a moderator: May 5, 2017
  10. Aug 11, 2011 #9


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    Not at all, BBT and GR avoid making any assumptions about preconditions [including space and time]. They only go back as far as the evidence permits. This starkly contrasts with things like M theory and branes, who boldly go where no observational evidence has gone before. Mathematical elegance can be a tempting deceptrix.
  11. Aug 11, 2011 #10


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    The galaxies are both moving within spacetime AND spacetime is expanding at the same time. Imagine the balloon analogy but instead of dots you have ants that are moving around. If we could continue to expand the balloon with it bursting, eventually the speed at which spacetime (the balloon) expands will be so great between 2 points that the ants cannot physically move fast enough to ever reach each other.

    There does not need to be a focal point for spacetime to expand from. The microwave background is definitely not fiction, it is an observable fact. All of the mass of the universe, to the best of our current knowledge, has existed forever in the universe. It did not spring up from nowhere.

    Motion is only measurable against another object. Generally we say that we are moving through space because it makes more sense than trying to claim we are motionless and everything else moves around us. So yes, the Earth spins, is in orbit around the sun, which is orbiting the galaxy, which is moving through space.

    No, it does not mean that at all. I can't hope to explain why, so maybe the FAQ will help you or someone else can.
  12. Aug 11, 2011 #11


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    You might be surprised how many cosmologists are not opposed to the idea that the matter comprising our present universe is not older than the universe itself. There is strong evidence the universe and its contents are of a finite age. The issue of precursor states [if any] is very unclear. At best, there was a phase transition between incarnations during which the state of matter, energy and the laws of physics are currently [and possibly forever] beyond our ability to observe, test, or describe with any degree of certainty. Here is an article by Paul Davies, a fairly reputable physicist, that may be of interest:
    http://www.fortunecity.com/emachines/e11/86/big-bang.html [Broken]
    Last edited by a moderator: May 5, 2017
  13. Aug 12, 2011 #12
    Great posts Drakkith. Thank you
  14. Aug 12, 2011 #13


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    The MATTER or the MASS?
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  15. Aug 15, 2011 #14
  16. Aug 15, 2011 #15


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    Nope. No focal point, as the event happened everywhere at once. The MATTER did not exist, as the beginning of the universe was too hot to form stable matter. After it expanded and cooled matter was able to form permanently.

    Current evidence points to an increasing acceleration of the expansion of the universe. Unless something changes then we will never come to a balance or collapse back in on itself.

    It isn't that they had different rules, it is that they interacted at energy levels that are difficult to recreate currently. I guess you could call it different rules, however I see it as existing rules that we don't know about currently. But it's just a different way of looking at it.

    Whether all mass existed before the big bang is arguable, as I have recently been informed that we have theories that predict different things for whatever was before the big bang. However, I can say that the big bang was NOT an explosion like you or I normally think of. Nothing "blew up".
  17. Aug 16, 2011 #16
    My poor understanding was that Hawkins M theory Was that a brain bumped in to a brain and that was the spark of the big bang.
    the theory that all of existence came from the big bang, from a singularity like point.
    leads a less that uneducated man to think that all the mater/mass of the universe came from a singularity.
    the only fathomable method would be that the universe collapsed on its self and all the mass/mater was consumed by SMBH's until there was only 1.

    As we always picture a SMBH as having the plumes on top and bottom. + that Hawkins believes they are "evaporating" (as I understand they lose some form of energy and can in fact dissipate) I followed a logic that says the singularity was there, became unstable and exploded releasing all its matter in to the universe. (heat + bla bla until it cooled enough for the subatomic partials then atoms to form)
  18. Aug 16, 2011 #17
    If that happened then why is the current Universe expanding and accelerating? Since it sounds like you are saying that Universe infinintly explodes and collapses on itself repeatedly. Right, unless something changes, then we are left to be in a cold and dark, lightless place. It also leads us to believe that there was only 1 BB

    The theory goes that the U was pure energy for the most part, with maybe some exotic particles thrown in there. As it expanded it cooled, and that energy was more stable and able to form atoms. Atoms came together and formed planets, stars, galaxies, etc etc. I have no idea how a pure energy can form into matter though..
  19. Aug 16, 2011 #18


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    Converting energy into matter is pretty easy, as long as you know what you are doing. Particle colliders crash protons or electrons together all the time and watch the shower of created particles come out. The rest mass of all these created particles GREATLY excedes the rest mass of the two particles that collided. The kinetic energy of the acceleratd particles was converted into matter. Note that no MASS was created or destroyed here.

    Similarly, photons can interact and create matter/antimatter pairs as well.
  20. Aug 17, 2011 #19
    Three years ago. I would have told you that "Yes, the universe as we know it expands to a balance point. then contracts due to the SMBH's. Until it all forms a single singularity and the entire time line starts over."
    With the introduction of "Dark mater and dark energy" I can no longer hold my ground on said theory.

    In regards to the "only 1 BB" if Hawking in correct and Membrane M theory is correct. This would imply a multiverse (Gary Gygax would be proud) and we are but one plane of existence. If the brane was not smooth and symmetrical of the brane that bumped in to us was not. then, multiple BB's could be the effect.

    Is the any proof that the universe's had more than one BB to start the universe? not that I am aware of.
  21. Aug 17, 2011 #20
    ^^ I think I do recall hearing that

    There has been evidence of a multiverse :smile: which makes me believe it more
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