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Post by marchesarosa on Mar 7, 2011 11:25:51 GMT 1
I think Eamonn has it right in right re high and low entropy.
But it's an understandable mix-up in terminology. The point stands that the direction is claimed to be usually from a more to a less ordered stated, whatever words are used to describe them.
Since I didn't watch the prog I don't know what I'm talking about, of course. Is the growing complexity of life via evolution an exception to the general rule?
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Post by marchesarosa on Mar 7, 2011 11:27:47 GMT 1
Sorry, cross posted. I see the matter has already been covered.
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Post by abacus9900 on Mar 7, 2011 11:47:15 GMT 1
I think Eamonn has it right in right re high and low entropy. But it's an understandable mix-up in terminology. The point stands that the direction is claimed to be usually from a more to a less ordered stated, whatever words are used to describe them. Since I didn't watch the prog I don't know what I'm talking about, of course. Is the growing complexity of life via evolution an exception to the general rule? You do know what you are talking about, marchesarosa. Terminology is less important in trying to explain a scientific concept than conveying the underlying principle involved. To try to explain an idea using unfamiliar terminology just confuses the reader. Why can't some so-called 'experts' understand this? Just because a mistake in terminology has occured should not detract from this.
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Post by jean on Mar 7, 2011 14:41:56 GMT 1
More discussion on this topic here.
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Post by speakertoanimals on Mar 7, 2011 15:53:17 GMT 1
No, because life isn't a closed system. The idiots who propose Intelligent design are of course quite fond of trying to raise this supposed evolution means disobeying the second law of thermodynamics bullshit.
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Post by abacus9900 on Mar 7, 2011 16:22:07 GMT 1
No, because life isn't a closed system. The idiots who propose Intelligent design are of course quite fond of trying to raise this supposed evolution means disobeying the second law of thermodynamics bullshit. How can the 2nd. law of thermodynamics be correct in view of the fact that our very own universe had to somehow 'evolve' from something, not a complete disorganized high entropy state - a sea of photons with a temperature of absolute zero? Time will have effectively ceased so it must all be rubbish. (Insults expected, as usual).
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Post by Progenitor A on Mar 7, 2011 16:44:28 GMT 1
How can the 2nd. law of thermodynamics be correct in view of the fact that our very own universe had to somehow 'evolve' from something, not a complete disorganized high entropy state - a sea of photons with a temperature of absolute zero? Time will have effectively ceased so it must all be rubbish. (Insults expected, as usual). I find that perplexing too, because the evolution of life from inert atoms is more complex and hence more improbable than the atoms being randomly distributed, as they were before life evolved. Therefore we have apparantly moved from a position of disorganisation - high entropy to organisation -low entropy, and that would appear to reverse the arrow of time (if the arrow of time is the movement from organisation to disorganisation as professor Cox maintained) For example anyone that maintains the City Of London as an organism is less organised now than it was 2000 years ago is surely wrong Even from considerations of the dilurton of energy, more energy can be extracted from nature now than it could be 2000 years ago I suppose it might be argued that, say 2 million years is but a hiccup in the evolution of entropy and although there may be local variations, the inevitable trend is toward increasing entropy. However it does seem as if time locally is reversible! What is the answer?
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Post by abacus9900 on Mar 7, 2011 16:45:12 GMT 1
STA, seriously, why can't you at least try to aspire to be the magnificent communicator that Brian Cox is?
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Post by abacus9900 on Mar 7, 2011 16:52:02 GMT 1
How can the 2nd. law of thermodynamics be correct in view of the fact that our very own universe had to somehow 'evolve' from something, not a complete disorganized high entropy state - a sea of photons with a temperature of absolute zero? Time will have effectively ceased so it must all be rubbish. (Insults expected, as usual). I find that perplexing too, because the evolution of life from inert atoms is more complex and hence more improbable than the atoms being randomly distributed, as they were before life evolved. Therefore we have apparantly moved from a position of disorganisation - high entropy to organisation -low entropy, and that would appear to reverse the arrow of time (if the arrow of time is the movement from organisation to disorganisation as professor Cox maintained) I agree naymissus. If the tendency of matter is to a more disorganized state then the chances of life, especially intelligent life, would seem to be highly improbable. I think the scientists may be missing something here - either there is a God who orchestrates things else some higher intelligence we cannot as yet define. Also, Brain pointed out that eventually all that would be left of the universe would be a sea of photons at absolute zero. In other words, there would no longer be any activity whatsoever and, hence, no time. So, where did out universe come from?
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Post by carnyx on Mar 7, 2011 16:56:03 GMT 1
I half-watched this prog last night, with its typical piccies of galaxies and portentious swirly music meant to evoke wonder, but the overall tone was depressing.
And I had to laugh at the TellyDon presenter sitting by a calving glacier, explaining that the water molecules could somehow jump up out of the sea and organise themselves into lumps of ice ready to fall off again .. but that it was improbable. But, that is PRECISELY what the water molecules had done, and were going to carry on doing it! How does he think they got there in the first place? And what is stopping them repeating the process? AGW?
Then, his sandcastle analogy found me getting a bit annoyed. That 'Nature' could actually arrange sand-grains into a castle shape, was being demonstrated in front of our very eyes!
Sorry, but I found the thing too metaphysical by far. The concept of entropy is a scientific convenience, and to elevate it into a metaphor is a matter for poets, and not scientists. Cox in this programme came across as neither.
But what on earth was this programme about? Dramadoc? Infotainment? Travelogue? Science edutainment? We had seen it all before, and done better. For example, the blue dot thing was a straight crib of Sagan's programme, and it was a bit cheesy even then; because one of Apollo astronauts had first coined it.
A waste of money. Derivative stuff. And Cox has an unfortunate cast of face which gives him an irritating half-grin, which the tellyfolk pfresumably think is 'photogenic' .. or god forbid ..'sexy'.
Verdict on the programme? 0/10. Nothing new. It would have been more entertaining to show the programme's project acccounts.
Anyway, that 'arrow of time' metaphor is a necessary bit of blab to cover up the irritating fact that the 't' of Newton's and Maxwell's formulae can go negative but the sums still work.
And on his 'Arrow of Time' thing .. here is an interesting thought experiment; Point a real arrow head first at a mirror. Check the time taken for the light from the real arrow's head, and the real arrow's rear flight feather, to reach your eye. Now compare them with the same time taken for the light from the mirror image's tip and tail to get to your eye. Is the reflection going backwards ? Is time in the reflection going backwards, too?
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Post by speakertoanimals on Mar 7, 2011 16:56:42 GMT 1
And now we see abacus and NM deliberately jumping on the creationist band-wagon........................
As regards life -- IT'S NOT a CLOSED SYSTEM. It takes a whole lot of energy to keep life going which is the ONLY reason we can swim against the entropy gradient. ANd if we do stop taking energy in, we soon follow entropy and become a pile of stinking mush..................
Hence not perplexing at all if you actually understand the first principles of thermodynamics and the second law.
As regards the universe --
What idiot thinks that the Big Bang was COLD? Most of the entropy in the universe is in the CMB (since by count far more CMB photons than anything else). And what the CMB does is get cooler as it expands, in order to maintain constant entropy. Hence as far as the universe is concerned, we have constant entropy in the CMB, a few weird entropy-increasing bits like stars undergoing fusion, a few as yet unknown bits like stuff disappearing into black holes.
But WHY anyone would think a sea of photons at absolute zero would have anything to do with where we CAME from is beyond me......................
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Post by abacus9900 on Mar 7, 2011 17:06:36 GMT 1
It's quite simple, STA.
If the 2nd. law is correct and matter inevitably ends up at absolute zero then where does the new energy come from in order to build future universes? Unless you think our universe was the one and only event ever to have happened. Not very likely though, eh? Do you believe in magic, STA, you must. Actually, it is support for some kind of creator.
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Post by speakertoanimals on Mar 7, 2011 17:13:26 GMT 1
WHY absolute zero? IF expansion stopped at some point, and big crunch happened, then the CMB would just heat-up again, just as it cooled on expansion, and entropy of that would remain constant. We would have had SOME increase in entropy due to fusion processes, but ENERGY per se isn't the problem. You are confusing the heat-death of the universe, with energy density, and energy density with entropy.
IF that was the END, that would be it, nothing to do with where we CAME from, because such a cold, dark end assumes that it is an END, there is no big crunch, no further universe.
It hasn't necessarily got any6thing to do with where we CAME from, except pointing that out the cyclic universe idea is pretty much dead in the water, no big crunch if expansion keeps going forever, until we have the thinnest wisps of the coldest matter left about, and everything too far away from anything else for any interaction to happen ever again.
I don't know WHY anyone should get confused by what are pretty simple things, and think that everything juse getting colder and quieter without end means that it could never have started...........................
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Post by abacus9900 on Mar 7, 2011 17:15:49 GMT 1
Um, entropy is a scientifically valid phenomenon and has been demonstrated experimentally, old boy.
But all Brain was doing was to point out that things tend to entropy because in the long term there are many more chances of chaos happening than organization.
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Post by abacus9900 on Mar 7, 2011 17:21:26 GMT 1
WHY absolute zero? IF expansion stopped at some point, and big crunch happened... How could a big crunch happen if there is no energy left to drive it? The universe will simply disperse to nothingness. This is why there must be a God, or at least some higher power to organize these things.
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