The Origin of the Universe: A Matter of Energy and Motion?

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The discussion centers on the nature of the universe's origin, questioning how matter could exist in a compressed state without motion or energy prior to the Big Bang. It posits that for the universe to be condensed to the size of a grapefruit, all motion must have ceased, implying a lack of heat and energy. However, responses clarify that the early universe was primarily energy, not matter, and that it was only after cooling that matter formed. The conversation highlights the misunderstanding of energy and matter as interconnected, emphasizing that energy is a property of matter rather than a separate entity. Ultimately, the consensus suggests that the universe began as pure thermal energy, evolving into matter as conditions changed.
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To compress the observable universe into the size of a grapefruit, it had to be devoid of all motion, and therefore all heat and energy.

Why wasn’t the heavy hunk of matter the size of a grapefruit that preceded the “Big Bang” that created our observable universe cold and without energy?

My reasoning:
We know that more than 99.9% of the universe is “empty” space and that everything is constantly moving: rotating, revolving, expanding, contracting—everything is in motion from the atoms in the chair I am sitting on to the earth, moon, sun, stars, and accelerated expansion of the universe. Even though atoms are more than 99.9% space and only contain a tiny amount of matter, atoms do not pass through each other because of the electrical field exerted by the spinning, revolving, rotating, matter within them. A rock that appears to be stationary is made up of atoms that are moving and producing an energy field.

For all matter within the universe to have been compressed into the size of a grapefruit, all motion had to have ceased. Without motion there is no heat or energy.

My conclusion is that matter must have pre-existed the expansion, and that the energy that caused the matter to begin moving and producing heat came from an external source.

Am I missing something?
jtb
 
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The very early univese is believed to have been so hot that even subatomic particles were unable to form [i.e., it was pure energy]. The first atomic nuclei did not form until about 3 minutes after the BB. It is fairly certain the universe was much larger than a grapefruit by then.
 
Well, no, this reasoning is fundamentally flawed. Basically, the hot particles in region A may be all moving at extremely high velocities, tending to leave that region very rapidly, but then the hot particles in the neighboring regions will be doing the same, and so on average the inflow of hot particles from neighboring regions cancels the outflow.

There's also the problem that your entire argument assumes a stable configuration, which never happened: our universe, as near as we can tell, was always expanding. And at very early times, this expansion was very rapid indeed.
 
jtban said:
For all matter within the universe to have been compressed into the size of a grapefruit, all motion had to have ceased. Without motion there is no heat or energy.

My conclusion is that matter must have pre-existed the expansion, and that the energy that caused the matter to begin moving and producing heat came from an external source.

Am I missing something?
jtb

It wasn't matter - it was energy.

It didn't form into matter until a long time after when conditions were cooler.
 
Chimps said:
It wasn't matter - it was energy.
Not really. Energy does not exist separate and distinct from matter. Energy is a property of matter.

A better way to say it would be that the average energy of particles far exceeded their rest mass energies, which meant that collisions would very frequently change the number of particles of a given type.
 
From the answers to my question it appears that originally the universe was infinitely smaller and hotter consisting of pure thermal energy with sub-atomic particles moving about frantically, and that there never was a cosmic egg, or starting point for the universe. The universe cooled as thermal energy decreased through work (conversion to the nuclear forces required to create atoms?) or somehow left the system for colder areas making it possible for matter and the present universe to come into existence.

Am I interrupting the answers correctly?
jtb
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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