- #1

- 1,984

- 3

## Main Question or Discussion Point

What would this be?

- Thread starter Mk
- Start date

- #1

- 1,984

- 3

What would this be?

- #2

cepheid

Staff Emeritus

Science Advisor

Gold Member

- 5,192

- 36

- #3

krab

Science Advisor

- 896

- 2

- #4

- 1,984

- 3

krab said:

It sounds like basic math, if A is greater than B and B is greater than C than A is greater than C.

- #5

Galileo

Science Advisor

Homework Helper

- 1,989

- 6

If C is initially in thermal equilibrium with both A and B, then A and B are also in thermal equilibrium with each other. This result is called the zeroth law of thermodynamics.

- #6

- 1,984

- 3

Mk said:It sounds like basic math, if A is greater than B and B is greater than C than A is greater than C.

- #7

arildno

Science Advisor

Homework Helper

Gold Member

Dearly Missed

- 9,970

- 132

True, but remember that "temperature" is some real property.Mk said:It sounds like basic math, if A is greater than B and B is greater than C than A is greater than C.

This means, that the physicist must explicitly assume that it is meaningful to measure as a number this real property.

There exist other properties in the world which it is doubtful can ever be quantified, for example, "kindness".

A physicist who wish to develop a mathematical model of the world, is limited in talking about structures of the world which is "mathematizable".

- #8

- 165

- 0

So the Zeroth principle says: Let have three thermodynamic systems, we say that if A is in thermal equilibrium with C, and also with B, C and B are at thermal equilibrium.

- #9

- 35,736

- 4,507

There are several things that make this actually non-trivial:Mk said:Again, if C=A=B, A=B

1. Remember that you are equating the

2. That equality will not be true if the 2nd Law is violated. So this is indirectly an entropy manifestation. I have seen many quacks who implicitly make use of the thermal equilibrium principle and yet, attack the validity of the 2nd law.

3. The 0th law is the very reason why, when metals and semiconductors of various kinds come in contact with each other, everything is scalled according to the location of the Fermi energy (or the chemical potential for semiconductors to be exact).

Zz.

- Replies
- 1

- Views
- 854

- Last Post

- Replies
- 1

- Views
- 529

- Replies
- 4

- Views
- 2K

- Last Post

- Replies
- 2

- Views
- 4K

- Replies
- 1

- Views
- 2K

- Replies
- 1

- Views
- 2K

- Replies
- 3

- Views
- 4K

- Replies
- 4

- Views
- 4K

- Last Post

- Replies
- 1

- Views
- 1K

- Replies
- 11

- Views
- 2K