Entropy:A concept that is not a physical quantity - Science a GoGo's Discussion Forums

Physics paper:
Entropy: A concept that is not a physical quantity Published in (SCI-E Journal) PHYSICS ESSAYS (Volume 25, Issue 2 (June 2012)).

PHYSICS ESSAYS is SCI-E Journal.
URL: http://physicsessays.org/toc/phes/25/2.

Download this paper here:
http://blog.sciencenet.cn/home.php?mod=space&uid=543672&do=blog&id=601593

OR
http://blog.sciencenet.cn/blog-543672-592073.html

I don't think that is exactly ground breaking news

Quote:

I thought of calling it 'information', but the word was overly used, so I decided to call it 'uncertainty'. [...] Von Neumann told me, 'You should call it entropy, for two reasons. In the first place your uncertainty function has been used in statistical mechanics under that name, so it already has a name. In the second place, and more important, nobody knows what entropy really is, so in a debate you will always have the advantage.'

Conversation between Claude Shannon and John von Neumann regarding what name to give to the or attenuation in phone-line signals.

Now if you had told me that you had worked out what Entropy was I might have got excited.

I should also say that under Quantum Mechanics there are far more compelling reasons why Entropy can't be something real.

- You can show Entropy is a unitary invariant.

Where was the last "real" thing you ever saw that was unitary invariant.

- Entropy can only go to zero if and only if you a pure state

Where was the last "real" thing you ever saw that could only be found to be not there if you provide a specific state.

Quote:

Where was the last "real" thing you ever saw that could only be found to be not there if you provide a specific state.

Wouldn't that be anything? I am here; I could only not be here if someone/something (probably myself) provided a specific state of my not being here.

Keep that up and I am willing to provide the "you not being here state"

As Clint may say "go ahead make my day".

Or, as Bernard might have said: "I only arsked".

Entropy is an extensive thermodynamic property that is the measure of a system's thermal energy per unit temperature that is unavailable for doing useful work. It is well discussed in the following document

http://us.docsity.com/en-docs/Entropy_and_Temperature__Lecture_Notes_-_Physics

Your link seems to require a registration before being able to read the whole document. Do you have an alternative link for this information?