Is there a minimum value for entropy?
Also is there a minimum incremental change for entropy?

I know there is a logarithm in there somewhere, so maybe I don't mean entropy.

I saw an article describing entropy as the log of the number of states of a computer byte (i.e. the number of bits). Does this suggest that the universe is discrete, or is there a non-discrete way of imagining entropy too? (Sorry I know this is probably a silly question.)

(March 18, 2015 at 5:05 pm)Mister Agenda Wrote:

(March 18, 2015 at 4:14 pm)Chuck Wrote: If laws governing the universe does not menifest itself in laws of the universe, how would you know what they are??

We don't.

(March 18, 2015 at 4:14 pm)Chuck Wrote: The problem with this is laws of the universe is the only set we have reason to believe to apply anywhere based on observation.

Yes, that is quite a problem for us, which probably has a lot to do with why we don't know exactly what happened before T=0.

(March 18, 2015 at 4:14 pm)Chuck Wrote: If one cavalierly throws out the only set of law that we have reason to suspect to exist, then one might as well admit one is not trying to find out what really was, but is prepared to accept anything thay sounds good without constraint.

The constraint is logic. To presume that the laws within the universe apply to the universe is to commit a fallacy of composition. Any implication that this means "one might as well admit one is not trying to find out what really was, but is prepared to accept anything thay sounds good without constraint" is entirely in your own mind. I am not prepared to accept any statement, no matter how good it sounds, about the universe unless it is supported by evidence.

For any rules governing the universe to exhibit evidence both discernible and interpretable within the context of the rules are operating inside the universe, The rules governing the universe must to a high degree be connected to and analogous with the rules inside the universe. So To suppose rules governing the universe could be radically different from rules apply inside universe is to propose a scenario for which discernible and interpretable evidence is in principle not possible.

So so for the rules governing the universe to be extrapolatable based on evidence interpretable from within the context of tge rules governing inside the universe, the rules governing the universe must exhibit behaviors that can be predicted from rules governing within the universe.

(March 18, 2015 at 5:40 pm)watchamadoodle Wrote: Is there a minimum value for entropy?

In classical physics I don't think so (not 100% sure), but in quantum systems there's the third law:

http://en.wikipedia.org/wiki/Third_law_o...modynamics

Quote:Also is there a minimum incremental change for entropy?

I don't think so...

How are you finding all our claptrap Griffin?

You can ignore all the fancy sounding science stuff, these guys just make it up I think :p

I don't really mind entertaining the idea of a first cause, though I've explained in the other thread why none of us are obligated to; first causes aren't always gods, that's a separate claim that requires more substantive addressing than just "but there's a cause, though!"

quote='Alex K' pid='901396' dateline='1426715278']

Quote:Also is there a minimum incremental change for entropy?

I don't think so...
[/quote]

If quantum mechanics assert variable values within the universe must be discrete, does that not mean some minimum possible differences in entropy must exist and would be defined by difference in entropy between two states in which there is the least possible number and magnitude of differences in variable which would result in some difference in entropy?

(March 18, 2015 at 5:54 pm)Chuck Wrote: If quantum mechanics assert variable values within the universe must be discrete, does that not mean some minimum possible differences in entropy must exist and would be defined by difference in entropy between two states in which there is the least possible number and magnitude of differences in variable which would result in some difference in entropy?

Well... QM does not assert that all variable values must be discrete. The energy levels of a hydrogen atom are only discrete because the electrons are confined in a small finite space. Roughly, the relative Energy increment goes like

Delta E/sqrt(E) ~ sqrt(2/m) h/R

where h is Planck's constant, m the mass of the particle, and R the size of the space in which the system is confined.

(March 18, 2015 at 5:47 pm)Alex K Wrote:

(March 18, 2015 at 5:40 pm)watchamadoodle Wrote: Is there a minimum value for entropy?

In classical physics I don't think so (not 100% sure), but in quantum systems there's the third law:

http://en.wikipedia.org/wiki/Third_law_o...modynamics

Quote:Also is there a minimum incremental change for entropy?

I don't think so...

I didn't understand the link, but this line jumped-out to me:

Quote:Physically, the Nernst–Simon statement implies that it is impossible for any procedure to bring a system to the absolute zero of temperature in a finite number of steps.

I suppose that means it is impossible to trace the universe back to time zero? (or maybe not... WTF do I know )

The finite number of steps sounds discrete to me. I edited my post to add this additional question (for you or anybody else )

Quote:I saw an article describing entropy as the log of the number of states of a computer byte (i.e. the number of bits). Does this suggest that the universe is discrete, or is there a non-discrete way of imagining entropy too? (Sorry I know this is probably a silly question.)

(March 18, 2015 at 6:02 pm)watchamadoodle Wrote:

Quote:Physically, the Nernst–Simon statement implies that it is impossible for any procedure to bring a system to the absolute zero of temperature in a finite number of steps.

I suppose that means it is impossible to trace the universe back to time zero? (or maybe not... WTF do I know )

No, that's just the opposite case! If you trace the universe to time zero, you get temperatures going to infinity and thus the equations break down, not zero.

(March 18, 2015 at 5:57 pm)Alex K Wrote:

(March 18, 2015 at 5:54 pm)Chuck Wrote: If quantum mechanics assert variable values within the universe must be discrete, does that not mean some minimum possible differences in entropy must exist and would be defined by difference in entropy between two states in which there is the least possible number and magnitude of differences in variable which would result in some difference in entropy?

Well... QM does not assert that all variable values must be discrete. The energy levels of a hydrogen atom are only discrete because the electrons are confined in a small finite space. Very roughly speaking, the Energy increment goes like

Delta E ~ h*c / Size

where h is Planck's constant. If the universe has finite size R, there will be an energy quantization of Delta E ~ h*c/R, but you'd never see it.

Wait, that's the relativistic formula. For low energy particles, it's

Delta E/sqrt(E) ~ sqrt(2/m) h/R

It seems to me all values are some composite of units of time, length, and mass. If time, length and mass are discrete, does that not imply all possible physical values must also ultimately be discrete?