"Heating" the Cold Dark Matter

Dear Jorrie,

...Bang was relativistic, had a low entropy...

"...entropy, the Second Law of Thermodynamics, and the arrow of time: "It is a matter of common experience, that things get more disordered and chaotic with time..."

Fine. On the other hand, consider that as the primordial entity (Grand unification energy?) cooled and spread to the 4 basic forces (Weak and strong nuclear, electromagnetic and gravity), which in turn created force-fields, which interacted to create sub-particles, then particles, atoms, molecules, etc., it shows higher and higher complexity and order, I.e: lower entropy. Where did I get it wrong?

If the so called "arrow of time" according to the second TD law, points to a lower state of potential energy and higher state of entropy, this is enough to drive someone nuts.

The third confusing daemon, is the intuitive correlation between high temperatures (e.g, plasma, in which atoms are destroyed) and high entropy.

Not to be confused with mathematical description which always seem to "agree with itself", the above mentioned is a conceptual confusion, basically, the kind which freaked me out ever since high school to accept the "zero rest-mass of the photon", which acquires kinetic energy with increasing speed. Hey!.. I was led to believe that zero times anything is always zero... Conceptual, kinda thing, see?

Regards, Yuval

Hi yuval, I have to think a bit about your entropy issues. One issue I can put straight is the energy of a photon...

It depends on the frequency and not on the speed (no 1/2 mv²), although the speed of light features in the energy if it is written as:

E_photon = hc/λ, where h is Planck's constant and λ the wavelength of the photon.

Regards, Jorrie

Thanks in advance

I remember a beautiful discussion about the second law, where the teacher was asked: How come earth has such low entropy (the most complex chemistry known around) yet getting lower and lower. In order to lower entropy you would need to provide additional energy. Isn't it a closed system? He replied: "No, earth constantly imports solar energy and tidal energy from it's surrounding environment. It's not a closed system, a lot of energy is invested in it's extreme low entropy, energy which, with the "right" conditions, can "leak" back into the surrounding"

Hi Yuval, yes, it is, as you put it, "a beautiful discussion about the second law, ..."

I agree that Earth is importing energy from the Sun and some other sources, but AFAIK, Earth is loosing energy to the Moon due to tidal effects. Whether that is made up by the rather feeble "moonshine" on Earth, I do not know, but I don't think so!

Local entropy can easily be lowered, but at the expense of increasing entropy of the total system. What comprises the "total system", I don't know. All I know is that our observable universe is loosing energy due to the redshift of photons. I think the general idea today is that entropy of the total universe increases...

Regards, Jorrie

...What comprises the "total system", I don't know...

we were encouraged to think in terms of: "increasing the entropy of the rest of the universe" the rest being the outside of a given system, subject to known conservation laws, especially the first TD law. just as in:

...I think the general idea today is that entropy of the total universe increases... - This may snuggly fit our intuition, if you take the entire universe as a closed system - according to the first thermodynamic law - But, is it ?

Hi Jorrie,

This is an article on dark matter I can live with. It seems a lot more logical than the last one you posted. I am also having trouble with the second law of TD. We "started" with just particles, but now we have stars with planets orbiting them, and life has formed on at least one. Isn't that more order instead of less?

Can you explain exactly what a relativistic proton is?

Regards,

S