[namaan (OP)]

Hey everyone,

Please consider a hypothetical universe where all the major forces (strong force, weak force, etc.) are all governed by an "application/program", respectively; a universe of course, of a grand, non-reductionist design.

My question is in such a hypothetical universe, does entropy require one of these grand programs to be fully defined? Or is a mere reductionist view of atomic/molecular bonds giving way enough for a full definition of entropy?

[Ethos]

Entropy:
A process of degeneration with increasing uncertainty, chaos, ect., specif., when regarded as the final stage of a system. If we view existence from the multiverse perspective, then I would presume to answer in the negative.

If the multiverse hypothesis is correct, there need be no begining nor an end. Thus, the law of entropy finds application only to systems like and similar to our own singular universe.

.............infy

[Andrew P]

My question is in such a hypothetical universe, does entropy require one of these grand programs to be fully defined? Or is a mere reductionist view of atomic/molecular bonds giving way enough for a full definition of entropy?

Entropy, and in particular the increase of entropy which gives a direction to time, comes about because the Universe is set up with very specific initial conditions.  It's then a basic property of more-or-less any physics imaginable (even physics that looks quite different from the physics in the actual universe) that the very specific state of the early universe evolves into a much more generic (less fine-tuned) state in the late universe. It's that evolution that we call 'increasing entropy'.

So, as part of your grand design, you need to carefully chose the initial state of the Universe. But you don't need to put in an extra program module to specifically account for entropy -- that'll take care of itself if you get the initial state right.

I explained a little about this, without actually referring to the term 'entropy', in a episode of Naked Scientists a couple of years ago... http://www.thenakedscientists.com/HTML/content/interviews/interview/856/ [nofollow]

Monthly astronomy podcasts - www.thenakedscientists.com/astronomy [nofollow]

[flr]

...does entropy require one of these grand programs to be fully defined? Or is a mere reductionist view of atomic/molecular bonds giving way enough for a full definition of entropy?

 The entropy does not require a grand design.
 And I do not believe it has nothing to do with molecular bonds.
 
 A collection of particles will eventually occupy all available space rather than staying constrained in a smaller subarea. Does it look as it needs a grant design for molecules to occupy all available space?.

[Soul Surfer]

Kinetic theory,  thermodynamics and hence entropy is a fundamental property of ANY universe consisting of a large number of independent particles interacting under ANY sort of physical(or chemical ) laws and is totally independent of its starting conditions.

Our universe could (in theory) have started off as totally uniform (or random) array of cold (stationary) hydrogen atoms with a volume and density approximately equal to the currently observed universe and it would have (eventually) evolved to create stars galaxies and planets similar to what we see today.  The really vital asymmetries that would drive it are gravitation and quantum mechanical uncertainty

[Andrew P]

Kinetic theory,  thermodynamics and hence entropy is a fundamental property of ANY universe consisting of a large number of independent particles interacting under ANY sort of physical(or chemical ) laws and is totally independent of its starting conditions.

I agree entropy can still be defined, independent of the special initial conditions, but it's not such an interesting quantity in that case.

Let me explain why I say that. The point is that the increase of entropy can only come about if the entropy starts off low. For instance, two different gases released separately into a box will mix together, and that represents an increase in entropy. But if you start out with the gases mixed in the first place, there's no way for the entropy to increase any further.

On a closer inspection of this, Boltzmann realized that entropy could decrease if you wait for an immensely long time. However basic modern cosmology doesn't have that picture: it assumes the universe somehow started out in the low entropy state. Inflation [nofollow] is (according to its more thoughtful proponents) a mechanism for generating a low entropy Universe in a way consistent with Boltzmann's view; in that sense the real 'initial conditions' are supposed not to matter so much, because they are hidden away from us by the inflationary epoch. (However these issues are very complex and still far from cleared up.)

The really vital asymmetries that would drive it are gravitation

Gravity's actually time-symmetric. The asymmetry comes from the fact that things don't start off in a gravitationally collapsed state (i.e. they start off smoothly spread out, not in black holes).

and quantum uncertainty

You're right that quantum mechanics generates its own arrow of time (in the conventional formulation), and the agreement between the entropy-derived arrow of time and the QM-derived arrow of time is then a rather odd coincidence. My personal view is that this is an illusory, and a fuller understanding of quantum mechanics will show us that the thermodynamic and quantum arrows of time have to be the same. (This is rather beautifully the case in, for instance, Everett's picture of quantum mechanics [nofollow].)

Monthly astronomy podcasts - www.thenakedscientists.com/astronomy [nofollow]

[Soul Surfer]

Andrew That was precisely the asymmetry I was referring to about gravitation not time asymmetry. 

It is also important to note that any unrestricted gravitational collapse (particularly rotational gravitational collapse) can release indefinitely large quantities of energy which could be converted into matter by pair production and effectively hidden behind an event horizon producing very similar conditions to those currently envisaged in the early stages of the big bang and inflation.  All that is needed is the existence of a process that creates the appearance of "space" possibly by a process that generates stable dark matter fermions (lets call them gravitinos)  for the collapse to be reversed and a new universe created with properties that are probably reasonably closely related to the universe that spawned it by the creation of the black hole in the first place.

This is one of the steps that can lead us to the possibility of a cosmology based on an embedded fractal multiverse that has evolved to enable complexity and not a largely sterile multiverse with a very low probability of the existence of a universe like ours.