Force unification in Big Bang

In summary, until the universe was one Planck time old, all the forces were unified into one. We don't know why they were unified, but it is believed to be due to the high energy and density of the universe at the time. It is unlikely that we could replicate this in a lab. Currently, electric and magnetic forces are unified into electromagnetic force, but it is possible that they could separate in the future. The standard model suggests that at a certain energy scale, all three interaction strengths become almost equal, leading us to believe that this unification is not a coincidence. However, the inclusion of gravity in this unification is still speculative. Being near a black hole does not necessarily involve high-energy processes, but there are theories
  • #1
I have been reading that until the universe was one Planck time old (10-43 seconds) all the forces were unified into one. Do we know why would they be unified? Is it very large temperatures and pressures? Could we replicate it in the labs one day? Today Electric and Magnetic force are unified into Electromagnetic force. Could they separate one day?
 
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  • #2
GhostLoveScore said:
I have been reading [where?] that until the universe was one Planck time old (10-43 seconds) all the forces were unified into one. Do we know why would they be unified?
No. We reason that, by current understanding, they must have been (for some ideas about physics to hold) ... due to the scale of the Universe at the time. You maybe want to treat it as an assumption to be tested.

Could we replicate it in the labs one day?
Nobody knows.
By current models - almost certainly not. This would involve compressing space-time itself.

Today Electric and Magnetic force are unified into Electromagnetic force. Could they separate one day?
The unification, in this case, was a mathematical unification ... a realization that what we had been calling two separate forces were, in fact, due to an underlying process looked at from different perspectives. This is to say: it's a correction of an historical misunderstanding: a mistake ... it is not clear how any existing force could separate into some collection of other forces as yet unknown but there is no reason to suspect that electromagnetism, should it split into other forces, would split into electricity and magnetism.

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=228x42016
 
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  • #3
I read it on the wikipedia article on Big Bang. I know, wikipedia is not very accurate, this is probably one of the mistakes.
 
  • #4
I think there is a tendency for sources to be a little glib when talking about big-bang cosmology. Wikipedia is echoing that.

You got to realize there are a lot of suppositions going on, and each model has a slightly different set.
The "accepted" one is the one that best passes Occam's razor ... in this instance, it is the one where the forces unify when the density is high enough.
It's one of the things you go into when you do a foundational cosmology course at post-grad college level. I'm having a real hard time finding someplace with a definitive statement about it. I've made a note to do something about that next time I have to teach this ;) so this is one of those cases where someone asking a "simple" question affects things at this end.
 
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  • #5
GhostLoveScore said:
I have been reading that until the universe was one Planck time old (10-43 seconds) all the forces were unified into one. Do we know why would they be unified? Is it very large temperatures and pressures? Could we replicate it in the labs one day? Today Electric and Magnetic force are unified into Electromagnetic force. Could they separate one day?
Well, one hint is given by the standard model. Interaction strengths depend on the energy scale of the process. One can show that for a certain energy scale, all three interaction strengths become almost equal. Because the corresponding energy scale is very high, and we suspect that the standard model needs extension for such high energy scales, many physicists suspect that this 'almost' is not a coincidence and becomes an 'exactly' once the standard model has been extended in the right way.

I think the inclusion of gravity in this unification is a bit more speculative, since we don't have a theory of quantum gravity yet. But I could be wrong here.
 
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  • #6
haushofer said:
Well, one hint is given by the standard model. Interaction strengths depend on the energy scale of the process. One can show that for a certain energy scale, all three interaction strengths become almost equal.

Would that mean that some forces are unified near the black holes?
 
  • #7
No. Being near black holes doesn't imply high-energetic processes. Actually, a local observer near the horizon doesn't experience anything spectaculair.

That is to say, when you look at it from a classical point of view. Nowadays so-called 'firewalls' are being proposed, and that would change the situation.
 
  • #8
So what is then high energy process?
 
  • #9
A process which involves an energy (e.g. center of mass-energy) comparable to the GUT scale, in this case.
 

1. What is force unification in the Big Bang theory?

Force unification in the Big Bang theory refers to the idea that in the early universe, all four fundamental forces (gravity, electromagnetism, strong nuclear force, and weak nuclear force) were unified into a single force. This means that they had the same strength and behavior, and were not distinct forces as we know them today.

2. How does force unification relate to the Big Bang?

The Big Bang theory suggests that the universe began as a singularity, a point of infinite density and temperature. As the universe expanded and cooled, the four fundamental forces gradually separated and became distinct. This process is known as symmetry breaking, and it is believed to have occurred during the first fractions of a second after the Big Bang.

3. Why is force unification important in understanding the early universe?

Force unification is important because it helps us understand the fundamental nature of the universe and how it evolved. By studying how the four forces were unified and then separated, scientists can gain insights into the conditions of the universe during the Big Bang and how it has evolved over time.

4. Is force unification in the Big Bang theory supported by evidence?

Yes, there is strong evidence for force unification in the Big Bang theory. One piece of evidence comes from the cosmic microwave background radiation, which is leftover radiation from the early universe. This radiation is uniform in all directions, suggesting that the four forces were once unified.

5. Can force unification be tested or observed?

While we cannot directly observe or test force unification in the early universe, scientists can study the behavior of the four fundamental forces at very high energies using particle accelerators. These experiments can help us understand how the forces may have behaved during the early stages of the universe and support the idea of force unification in the Big Bang theory.

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