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Force of Big Bang

  1. Jan 30, 2015 #1

    Wes Tausend

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    What Fundamental force is most associated with the creation of the Big Bang? I never see one mentioned.

    Is it considered a possibly still un-named new force? Or is the theory still undeveloped to the extent that we have an effect without cause?

    Wes
    ...
     
  2. jcsd
  3. Jan 30, 2015 #2
  4. Jan 30, 2015 #3
    Big Bang cosmology is based on the idea that the four fundamental forces were unified in the early universe. It is hinged upon proposed ToE's (Theory of Everything) that offer explanations as to the nature of the universe up until approx 10-43s. After this, gravity interacts as a separate force. This period is known as the GUT (Grand Unified Theory) era. It lasted from approximately 10^-43s to 10^-35s. After that the elctroweak force splits from the strong force. Some time later the elctroweak force splits into the electromagnetic force and the weak nuclear. This is at around 10^-3s. Now there are four fundamental forces.

    You don't hear the term "Fundamental force" associated with the creation of the Big Bang. The creation of the Big Bang isn't a topic which you see scientifically explored so much as working on a ToE.
     
    Last edited: Jan 30, 2015
  5. Jan 30, 2015 #4

    phinds

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    The Big Bang Theory is totally silent as to the origin of the universe (which is what I assume you mean when you say "the creation of the big bang"). It is a description of the evolution of the universe starting one Plank Time after whatever it was that happened at t=0. If you already know all that and are looking for the force(s) available at one Plank Time, then the previous posts will be more helpful to you than what I have said.
     
  6. Jan 31, 2015 #5

    Wes Tausend

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    Thanks for the info and links guys.

    I'm not sure whether the imagined geometry led to the math used, or if some semblence of geometry began to appear from math. A bit of both I suppose, as the current, but incomplete, philosophical model appears to be solidly math based. I presume the act of reverse engineering Hubbles observation is really an effect still looking for a positive single cause.

    The idea that all four Fundamental forces may have been united into one in the early stage is something new for me, and quite intriguing. I can somewhat controversially equate electromagnetic and gravity, but I don't know much about the strong and electroweak forces and their connection.

    Wes
    ...
     
  7. Jan 31, 2015 #6

    DaveC426913

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    Apropos of nothing,

    In a recent book I read, there was an awesome description of how to conceive of a symmetrical, yet unstable early universe, breaking and reducing to an asymmetrical yet stable state (explaining why, for example gravity is so vastly weaker than the other forces).

    It describes the geometry of the universe as like a fitted bedsheet stretched tightly over a mattress. Anyone who has done this knows that, in order to get the bedsheet over all four corners, the mattress will be so curved that it does not lie flat on the bed. The construct is symmetrical (all four corners are fitted) but it is unstable (under tension).

    And then invariably, one corner will let go. The mattress will shoot back, and lie flat. This is quite stable and yet quite asymmetrical. Three corners are fitted, one is not.
     
  8. Jan 31, 2015 #7

    phinds

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    Could be just a matter of choice of words, but I want to make sure you are clear, "may have been" is a very weak description of the certainty with which this is viewed. Nothing in physics is ever proven for sure but the way in which the forces separated from a unified force is a good solid theory.
     
  9. Jan 31, 2015 #8

    Wes Tausend

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    That sounds like a great, easy to remember analogy, Dave. Thanks.

    I do question in one sense why we generally regard gravity as weaker than electromagnetism. Of course a magnet can pick up an object against the ficticious force of gravity which says electromagnetism seems the stronger force. But the one exceptional sense is that the two normal atomic forces, one proper, one fictious, are always found in the real world to be identical to each other on average. As an example, there is a specific spacing between atoms of gas in our atmosphere at sea level and a greater spacing at an altitude of say, 20k feet, with all atmospheric compression being fundamentally due to gravity, and all further compression fundamentally being held in check by matching emf.

    In both cases above, the gases are compressed just enough so the electromagnetic repulsion always equals the overall classical "attraction", or the GR curvature. Another more extreme example would be a much larger planet than earth mass-wise, where in a crude sense, the orbitals nearly touch the nucleus, while the atoms are very tightly packed. Even in this extreme, the exertion of a body's total gravity precisely matches the total exertion of the same body's electromagnetic force. As I worked it out, the query that I could possibly equate gravity with electromagnetic forces is partially based in this supposed "congruence" being true.

    Wes
    ...
     
  10. Jan 31, 2015 #9
    I didn't entirely understand your explanation of force due to gravity equalling the force due to electromagnetism.

    The electromag force is quanititatively stronger. It is easy to visualise how much stronger it is. Imagine a fridge magnet. The attractive force (N) between it and your fridge is enough to overcome the attractive force (N) that the gravity due to the mass of the entire Earth exerts on the magnet.
     
  11. Jan 31, 2015 #10

    DaveC426913

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    When did gravity become fictitious?
     
  12. Feb 1, 2015 #11

    Bandersnatch

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    'round 1915, I reckon. He means GR curvature.

    I'm not buying the argument in post #8 either. First of all, it assumes the molecules in the atmosphere are held against compression by EM interactions, where it is actually due to their kinetic energy (temperature). EM repulsion comes into play only during collisions.

    A more correct way to describe it would be to use solid material, where EM interactions hold molecules in a rigid structure, and place it at the surface of a body massive enough to break the bonds between the molecules.

    Now we do have EM acting against compression due to gravity.

    But then again, at best it shows precisely how weak gravity is compared to EM - you need a whole planet to overcome the EM repulsion between two molecules.
     
  13. Feb 1, 2015 #12

    PeterDonis

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    If it can hold the atmosphere in place or hold the Earth together against the EM repulsion between its atoms, in what sense is gravity "fictitious"? I realize that word is often used in discussions of gravity in the context of GR, but that doesn't mean it's always appropriate.

    He may think he does, but he doesn't. Spacetime curvature in GR is tidal gravity. Tidal gravity is not what holds the Earth in place against the EM repulsion between its atoms, or the atmosphere in place against the kinetic energy of air molecules.
     
  14. Feb 1, 2015 #13

    Wes Tausend

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    I was a bit casual in my choice of words. I do agree that, "the way in which the forces separated from a unified force is a good solid theory", and I do appreciate you commenting so. It is good to be able to come here and see why science developed as it did, and how it must work, even if it may seem austere at times.

    As of late I have been enamored of an education series of Annenberg Media on the net, and a featured Dr. Goodstein of CIT, said something to his class that makes a lot of sense to me. He said that SR and evolution theories are both so well proven that they have been effectively raised to fact in the minds of men, not just theory. Unsaid, other theories are apparently still just theories, albeit many with a lot of corroborating evidence such as thee beginning, near Planck time.

    I think we might agree, as important as it is for all of us, you and I included, to fathom current majority beliefs, it is also important that all realise every theory is subject to improvement, even though it may eventually only be tweaked however minutely. I am old now, but I think it is especially important that young up-and-coming students realise, and be encouraged here, that they must continue to question that, which all men now "know", even if that is definately not the central theme of this forum. Even the pathways of SR (and GR now also assumed factual) are probably not perfect, or our Theory of Everything would be readily at hand.

    Wes
    ...
     
  15. Feb 1, 2015 #14

    phinds

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    Sure, GR in particular is well known to be an incomplete theory since it just can't handle things at the quantum level, and QM is as much fact as any theory can be (Feynman was fond of saying 50 years ago that QM has been tested experimentally and the results margin of error to the theory is the same as measuring the width of the continental US to the width of a human hair) but it too is incomplete since it can't explain the macro level stuff that GR does. So we KNOW that we need either a unification of QM and GR or some whole new theory, but for practical purposes they are both very sound, just a Newton's Law of Gravity is sound at local scales even though it is clearly wrong at large scales and high speeds).
     
  16. Feb 1, 2015 #15

    Wes Tausend

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    I only meant to positively differentiate that I regard emf as a proper force as opposed to Einsteins GR gravity which I regard as a fictious force like that of centrifugal force (unlike Newtons gravity, proper again). I could be dead wrong here.

    I might be wrong here too. First I don't believe there is ever a full collision, but the "particles" of atoms are held in abeyance from touching by emf. This should occur even at absolute zero where no extraneous "heat" kinetic energy remains, but just that of coulomb repulsion for lack of a better term. In other words the emf effects are still equal to the gravitational effects.

    The way I had to look at it was to imagine that all loose particles, liquids and gases, regardless of temperature, actually behave somewhat like monopoles and are held apart by EM. For now, I am avoiding compounds where two atoms are covalently bonded although we must consider why they do not, once started, collapse entirely into one another. I don't feel comfortable to get too innovative on this forum, but thought readers might find it entertaining that EM and gravity are at least equal under some circumstances. Even Einstein looked for a key.

    Exactly! The exertion of EM precisely equals the exertion of gravity... when one considers the entire planet body as a unit. And remember, gravity does appear to overcome EM in a black hole if I am not understating it. Gravity is stronger... sort of.

    This is way out there, but...
    Considering the rest of my line of thought, I think that I might be able to postulate that the total emf and total gravity are equal throughout the universe. They both depend on the same mass. But in some ways this has already been done by Einstein not quite in those words.

    I have guests arriving for SuperBowl...

    Wes
    ...
     
  17. Feb 1, 2015 #16

    PeterDonis

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    Again, there is a sense in which this is true, but it is not the sense in which "gravity" is meant if we are talking about "gravity" as what holds the Earth together against the EM repulsion between its atoms, or holds the atmosphere in place against the kinetic energy of air molecules (and the effects of collisions between them).

    If you look at a small enough scale, yes, this is true--sort of. At a small enough scale, atoms are quantum objects, and what causes them to repel each other is that there is a limit on how closely their quantum wave functions can overlap in space. What causes this limit is rather complicated; it's a combination of the EM force and the Pauli exclusion principle.

    But if we're just looking at a gas like the Earth's atmosphere at the level of statistical mechanics--the kinetic theory of gases--then we are ignoring the small scale physics that underlies their collisions. We're idealizing the atoms as little point-like billiard balls that just bounce off each other elastically, just like in the simple Newtonian models you find in high school physics class.

    I don't think so. This doesn't seem like a description of anything in GR or anything that Einstein did.
     
  18. Feb 1, 2015 #17

    Drakkith

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    You're comparing apples to oranges here. Gravity becomes strong enough to keep an EM wave from propagating outwards from beyond an event horizon, but this has nothing to do with the EM force. It's simply a matter of worldlines. There aren't any paths any object (including an EM wave) could take through spacetime that would lead it away from the black hole. The issue here is that the EM force itself doesn't propagate. Only changes within the field propagate, and these changes move at c as EM waves. You can have an electrically charged black hole.
     
  19. Feb 3, 2015 #18

    Wes Tausend

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    Peter, Drakkith,
    I apologise for the delay in getting back to my own thread. I hope everyone enjoyed the SuperBowl in some manner. One of the most thrilling.

    I had to think very carefully what to say next, since it seems I've opened a can of worms, perhaps due to my own struggle to understand. I thought the simplistic novel(?) idea that the expended total gravity of a single body seemed always equal to it's expended (not potential) emf for separation, was self-evident and perhaps even possible to extrapolate to all magnetic/inertial forces and space. It is a subtle thing, but apparently I may be mistaken in this assumption, that I am either dead wrong or it is just not easy to see.

    Drakkith,
    I wasn't thinking of EM radiation from a black hole, but rather the simple minimum spacing that all matter exhibits otherwise known as (planet/body/particle) mass density. The more the gravity, the more compacted the mass density in a given space. In a black hole, regarding "spacing" that is normally associated with EM forces, the density may be as much as infinite with no spacing. If all the universe were reduced to a single black hole, gravity should not be the weakest, but logically appear to win the dimensional force war against all associated combined electro forces. Of course we cannot literally see within to actually measure any internal density as infinite, balanced or otherwise.
    ----------------------------------------------------------------------------------------------------------------------------------

    Peter,
    I mentioned that total gravity may equal the total emf of the universe. I find it would be an extraordinarily useful ratio to contemplate if it did, but if neither Einstein, nor anyone else of similar bearing, has said something to this effect, the statement may not belong here on PF? I can't reference it directly either, but is it not at least reasonably symetric to SR by merely saying total energy (manifested in joules of force) must be equal to total mass (manifested in "equivalent" inertial forces)?
    =========================================================================

    smbrk.gif

    Considering the above photo-diagram, when gravity split from all the other forces, is it thought to have split in equal proportion to the sum of the rest, or some other proportion, and how would we determine that in certainy? The photo is taken from http://hyperphysics.phy-astr.gsu.edu/hbase/astro/unify.html .

    Wes
    ...
     
  20. Feb 3, 2015 #19

    Drakkith

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    I'm sorry I have absolutely no idea what you're talking about. I don't know what 'expended total gravity' is, nor what 'expended emf' is.

    I wasn't referring to EM radiation either. I was referring to an electric field. Regarding the strength of gravity, there's a difference between the 'raw strength' exerted by an object and the ratio of strengths between the forces. Gravity is about 10-36 times as weak as the electromagnetic force. The only reason gravity can ever 'overpower' the EM force is because gravitation is always attractive, never neutral.

    Also, saying 'mass density' is redundant. Density is defined as mass/volume, so you can just say density.
     
  21. Feb 3, 2015 #20

    PeterDonis

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    This is not correct. A black hole is a vacuum; it is not an ordinary object with matter packed inside it.

    This doesn't make sense; energy is not force and Joules are not units of force, and a given mass does not have a unique "equivalent" inertial force (you can exert any force you like on a given mass).

    What do you mean by "proportion"? The width of the various lines in the diagram you gave does not correspond to anything physical, so I'm not sure what you're talking about. If you mean "strength of force", then obviously not; the strengths of the different forces are different.

    (More precisely, since "strength of force" depends on the energy scale at which you measure it, the different forces vary in strength differently with energy scale, so that at the energy scales common in our universe now, they have very different strengths; the "unification" of the forces occurs at a very high energy scale at which all the strengths become equal.)
     
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