I Uncertainty Principle in QFT & Early Universe Conditions

victorvmotti
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Does uncertainty relevant about the origin of the super hot state, or infinite amount of energy, of the early universe?
I have a question related to the uncertainty principle in QFT and if it is related to the early universe conditions.

Do we still have four-vector momentum and position uncertainty relation in relativistic quantum theory?

I have been following the argument related to the early universe and the emergence of matter-energy from nothing.

They often refer to the notion of quantum fluctuations.

But I wonder if a simple explanation goes like this, instead:

Since in the early universe, the scale factor in the Standard Model approaches zero, we could say that the volume of spacetime, in the proper frame, is arbitrarily small and therefore the uncertainty of spacetime is close to zero. As a result, the uncertainty of momentum-energy must be arbitrarily big, close to infinity.

So, one can conclude, simply using the uncertainty principle, that close to the big bang singularity, infinite momentum-energy is available in the early universe, which evolves first into radiation dominated and then matter dominated cosmos.

Is this argument correct?

My key question is about the origin of the super hot state, or infinite amount of energy, of the early universe, and not related to the later stage, i.e. formation of matter and antimatter and leptogenesis.

Put it another way, are we talking about quantum fluctuations of the vacuum to basically mean an application of the uncertainty principle in a universe so compact that the uncertainty of spacetime is almost zero and hence the momentum-energy uncertainty is almost infinite?

Can we just use the uncertainty principle to explain something from nothing?
 
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victorvmotti said:
Since in the early universe, the scale factor in the Standard Model approaches zero, we could say that the volume of spacetime, in the proper frame, is arbitrarily small and therefore the uncertainty of spacetime is close to zero. As a result, the uncertainty of momentum-energy must be arbitrarily big, close to infinity.

So, one can conclude, simply using the uncertainty principle, that close to the big bang singularity, infinite momentum-energy is available in the early universe, which evolves first into radiation dominated and then matter dominated cosmos.

Is this argument correct?
No. It's not even wrong. And it's personal speculation, which is off limits here.

Thread closed.
 
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