Was the majority of the universe created by fusion?

Ummmm…. ….

 

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What does "ummmm" mean?

Stars are created by fusion. We don't know what dark matter or dark energy is. What is your actual point or "revelation"?

 

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No. The majority of the universe's normal matter is hydrogen (74%),which was created during the recombination epoch, when the universe cooled enough for electrons to recombine with protons to make the first atom.

Helium and lithium were also created during the recombination epoch and they make up the rest of the matter.

Only after that did stars start fusing these light elements into heavier elements which make up a tiny fraction of the universe.

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Point… a component of our reality that has no temperature defies all belief. Yet it exists in reality because your imagination exists in reality.

We don’t know how fast heat or cold dissipates because of dark matter.

You think it gets frozzen out but it only increases in efficiency because the pulleys all start working together

 

How do you account for the elements above iron?

Percentage iron PI

 

I’m just a simpleton

 

rapid neutron capture in exploding supernova is usually the mechanism for production of elements heavier than Iron. those beyond Uranium have decayed out, so we only observe the longer-lived elements such as U-235 and U-238, Pb isotopes, etc. the high neutron environment from rapid fusion in the center of the exploding star allows for rapid build-up of the heavier elements. it's a whole field to study that. i like the idea that if the relative abundance of U-235 and U-238 were roughly 50%-50%, then we can date when that supernova occurred to create our earth's uranium, since they both decay at known rates to give the current relative abundances. solving those two equations with two unknowns yields about 8 billion years ago.

 

Of course the overwhelming majority of beaconator's posts are gibberish but this one thing got me thinking.
Since dark matter does not appear to interact with EM radiation, that would mean it does not absorb or emit infrared radiation so does the concept of temperature even apply to dark matter?

 

The technical definition of temperature is the average kinetic energy of a volume of particles, so it doesn't have to have anything to do with IR absorption/emission.

 

True. However, it also raises the question of how an ensemble of dark matter entities can exchange energy so as to come to a Boltzmann distribution. Can they repel one another electrostatically if they don’t interact with an EM field? After all, electrostatic interactions are mediated by virtual photons, aren’t they? So without that, how can they “collide” ?

Perhaps they pass through one another, a bit like neutrinos. If they do that they won’t settle into an equilibrium energy distribution - and then they won’t have a temperature, it seems to me.

So I agree that this is a rather interesting issue.

 

Thinking about this a bit more, since dark matter doesn't clump, that is, it doesn't interact with other dark matter or normal matter temperature is not really defined for single particles.
Cross posted with exchemist.

 

When you say it doesn’t clump, it has mass and responds to gravitation, since it is concentrated in galaxies.

 

Right, but I am saying dark matter particles don't make 'dark matter molecules' or 'dark matter crystals'.

 

Indeed, because both chemical bonding and Van der Waals forces come from electrostatic interactions - and dark matter does not do EM interactions, apparently. But you can have a temperature in a monatomic gas in which both are absent or virtually so, as long as you have collisions to distribute k.e. into a Boltzmann distribution.

That’s why I think it is the absence of collisions that would lead to a lack of any defined temperature.

 

Moreso: dark matter doesn't respond to any of the fundamental forces *except* gravity, so the atoms don't even bump into each other. They pass right through. They *only* interact via gravity.

 

Well now I feel joy. I can finally understand you all!

 

Like dark matter floats right through us at the same temperature, thus the universe accelerates.

 

God could have been the first chemist to make himself both explode and implode at the same time…

 

Scroll up first.

concentrated in galaxies yet restricted above the outer limit. Everywhere else has hydrogen to fill a void

 

Is it so impossible for dark matter to reach twice the speed of light before demonstrating fusion?