Alright, now I’m confused. Entropy is the measure of a system's thermal energy per unit temperature that is unavailable for doing useful work. But it is also a measure of the molecular disorder, or randomness, of a system.

The entropy of the universe is apparently increasing. But this doesn’t make sense. Clearly things are becoming more ordered in the universe, are they not?

Secondly, it seems to me that with our knowledge of the formation of stars, galaxies, etc, and all the laws of physics therein, the entropy involved would fit perfectly well with known concepts.

How could it not?

Surely it has to be a matter of accepting the energy and entropy involved as being perfectly normal, and for people like Penrose to find the mathematics that fit this normality, rather than coming up with what must be considered highly wonky calculations that indicate entropy to be extraordinarily low!

I'm surprised at the reaction to this thread.

LUDWIG,

Observation suggests the universe is becoming more DISORDERED. Stars condense out of gas clouds under the influence of gravity as you point out. That decreases the entropy of the gas molecules.

However the gravitationally induced compression of the gas heats it up. In consequence it radiates photons of electromagnetic energy. The entropy of the photons exceeds by orders of magnitude the decrease in the entropy of the gas molecules. The result is a NET INCREASE in entropy.

LUDWIG & BUGSY,

The improbably low entropy of the observed universe is NOT controversial. Most cosmologists would agree there is a conundrum to be resolved. All Penrose did was attempt to estimate, in a rough and ready way, the DEGREE of improbability. To my knowledge no cosmologist challenges it as a rough and ready calculation.

Comparisons with Dembski are fatuous. Dembski ignored almost everything that was known about evolution. Penrose has as good an understanding of cosmology as anyone.

BUGSY

I'm actually agreeing with you. As you can see, my favoured answer is 4 – we don't know enough.

CONTROVERSY

I've made only two arguments that would be regarded as controversial by most cosmologists.

(1)The critique of the infinite universe / multiverse explanation. This is the current favourite in the cosmology community.

(2)The statement that with our current state of knowledge we cannot decide between the four answers.

You and I Bugsy probably both think Answer 1, God dunnit, is a non-starter. But right now we cannot falsify that assumption as we can, say, creationism.

ANTHROPIC PRINCIPLE

See:

http://www.anthropic-principle.com/

You may not like the anthropic principle Bugsy. I have no strong feelings either way.

But let's see your explanation for the strangely life-friendly laws of physics that seem to govern our universe.

Remember, Bugsy, the universe is under no obligation to please you

I only mentioned Dumbski as an example of how incorrect assumptions can lead to stupid answers. So please don't think that I am making a proper comparison. I am sure that Penrose is orders of magnitude better.

But competing ideas that cannot be falsified are essentially useless.

The anthropic principle is like asking why player X is the winner of a poker tournament and coming up with the answer that it could not have been otherwise. It was highly improbable for X to win and yet all the conditions occurred for that event or state to occur. Why? because it happened, that's why. If it didn't happen in that precise way, then we would be discussing another set of events or conditions. To say that the universe is "strangely life friendly" means that cosmologists don't really know enough about life itself. We will certainly know more when we find another form of life. Until then the cosmologists can continue to have their heads up their own astronomic calculations.

“The entropy of the photons exceeds by orders of magnitude the decrease in the entropy of the gas molecules.”

Steven, don’t you mean the free energy of photons greatly exceeds that of the gas molecules, and hence the entropy is less?

The energy available for doing work is surely increasing as stars condense and radiate energy. Hence entropy would be falling, if the overall amount of energy (or mass/energy) is constant, wouldn’t it?

I can’t possibly envisage how the universe could be becoming less ordered as a result or the formation of stars and their radiation of energy. It is becoming more complex, but that doesn’t mean more randomised.

Welllll... last saturday I was facing an opponent in a boxing ring, and I left my belly WIDEEEE open and exposed, as a bait for my opponent to see it as an irresistable target to front kick, (a move for which I have a ready solution :) but here.. I do the same verbally, and I'm ignored.. grrr aah well.. with all the intellectual 'muscle' apparent here it is clear that we are operating at different levels.... understandable of course, given that I myself totally ignored the scientific speculation...

Don't take that as 'head in the sand'.. but the speculation (specially as described by Pericles "this leads to new questions, I live for this" kind of thing) reminds me so much of what the Apostle Paul encountered in Athens, that I hesitate to engage on the scientific level.

Acts 17:21 All the Athenians and the foreigners who lived there spent their time doing nothing but talking about and listening to the latest ideas.

My response to the thread was same as Pauls:

"Men of Athens! I see that in every way you are very religious. 23For as I walked around and looked carefully at your objects of worship, I even found an altar with this inscription: TO AN UNKNOWN GOD. Now what you worship as something unknown I am going to proclaim to you.

For the word 'religious' you can substitute the word 'scientific', and given Steven's point 1.... may I dare suggest your enthusiasm is in fact 'to an unknown god'...

Paul then outlines the Gospel, albeit with a naturalistic beginning.
His conclusion though is spot on:

31For he has set a day when he will judge the world with justice by the man he has appointed. He has given proof of this to all men by raising him from the dead."

Thats the crux. How did Paul know this ? 'Damascus Road'.

Ludwig,

Below is the best online link I can provide for an explanation of the increase in entropy that results from stellar formation.

http://math.ucr.edu/home/baez/entropy.html

In simple terms:

As a gas cloud condenses under the influence of gravity the "space entropy" of the gas decreases. However the molecules of gas speed up so the "momentum entropy" increases. The increase in "momentum entropy" is less than the decrease "space entropy" so there is a net LOCAL decrease in entropy.

BUT

The photons the gas molecules radiate, mostly in the far infrared at this stage, have a huge "space entropy" because they spread out in large numbers – zillions per molecule – at the speed of light. So there is a large overall increase in entropy as the gas cloud condenses.

Bugsy,

I don't know why you are so emotional about this. One way science advances is by resolving conundrums.

Here are some conundrums that have led to advances in science.

--The retrograde motion of the planets led, eventually, after a detour through epicycles, to ditching the geocentric model of the solar system in favour of the heliocentric model espoused by Aristarchus and Copernicus.

--The inability to make the Copernican model fit observation led Kepler to the discovery that the planets move in elliptical orbits in such a way that, inter alia, the radius vector traces out equal areas in equal times. Kepler's discoveries led in turn led to Newton's inverse square law of gravity.

--Discrepancies in the transformation properties of Maxwell's equations compared to Newtonian dynamics led Einstein to special relativity. This also resolved the conundrum of the null result of the Michaelsen-Morley experiment.

--The conundrum of black body radiation led Max Planck to quantum mechanics.

Penrose has helped publicise an interesting conundrum and I'm sure new scientific insights will result from our attempts to resolve it.

So why the emotional reaction and comparisons with Dembski?

A major conundrum for Darwin in the 19th Century was: What fueled the sun for billions of years?

SCIENCE THRIVES ON CONUNDRUMS