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I found this article interesting. I had never heard of Anthropic selection before, and I'm surprised that it is gaining some legitimate support in the scientific community. If it is indeed true, then does this support the possibility of a creator? (This sounds like ammo for the ID fanatics)

 

http://www.space.com/scienceastronomy/060508_mm_cyclic_universe.html

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I found this article interesting. I had never heard of Anthropic selection before' date=' and I'm surprised that it is gaining some legitimate support in the scientific community. If it is indeed true, then does this support the possibility of a creator? (This sounds like ammo for the ID fanatics)

 

http://www.space.com/scienceastronomy/060508_mm_cyclic_universe.html[/quote']

 

I think it is losing support

 

there was an "Anthropic Principle" fad starting around 2003 that was a big topic of discussion in 2004. Then the air went out. By 2005 some people had reconsidered.

 

In summer 2005 there was a big conference of string theorists in Toronto called Strings '05 where they had a straw vote after a panel discussion and about 3/4 voted against Anthropic explanation. This is on video and I have watched it several times. Someone in the front of hall, probably one of the panel, says "Sh*t!"

and a mike picked it up.

 

People who were there were surprised---it was 3 to 1 or some said 4 to one---they wanted physical reasons for why the constants are as they are---they didnt like the Anthrop explanation that this is just how it is because it allows life to exist and here we are so it had to be that way.

 

What you report here is the article in Science by Steinhardt and Turok. It is very much in line with this loss in popularity of Anthropic reasoning.

Steinhardt Turok propose a WAY TO DEFEAT anthropery by supplying and ALTERNATIVE EXPLANATION of how one of the constants came to be what it is.

 

They also politely explain why the Anthropic reasoning undesirable, in their Science paper.

 

Here is the Science paper in preprint form if you want:

http://arxiv.org/abs/astro-ph/0605173

 

I THINK THIS IS THE TECHNICAL ARTICLE THAT YOUR PUBLIC MEDIA ARTICLE IS TALKING ABOUT--it's publication in Science journal is the new item that the space.com journalist is reporting, this article is ANTI-anthropic, not pro-anthropic.

 

You came in on the tailend. the fashion now is to more to despise and shun Anthropic thinking, and to try out alternative mechanisms.

 

But there are die-hard holdouts----especially a bunch at Stanford. Lenny Susskind, Andrei Linde. And some people funded by a religious outfit.

 

you can still find some very prominent bigname people who will give you a (heavily qualified) version of the Anthropic story. But I'd say it has past its glory days and is getting old. (just my private take)

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Whap.

lambda is not the only constant these ideas apply to. If we added up all the constants of physics, and noted their tight adherance to a narrow range of values that permit a universe that can develop life, then we have a universe whose probability is so low, that it might as well be zero.

 

On the face of it, this is very strong evidence for a creator, who made the universe according to tight specifications. For it to happen by chance would be almost inconceivable.

 

The anthropic principle is the way out of this conclusion. However, the idea of the universe having areas with different values of lambda in different parts of this universe makes no sense, since there are a number of other values that would also have to vary. The sum total suggests that to have even one solar system with the right values, requires a probability so low that we can ignore it.

 

( I have not calculated this. This is more intuitive, but I doubt any respected physicist would disagree. It was originally pointed out to me that there are six vital constants. eg. the ratio between the strength of gravity, and electromagnetic forces. To get all six within the tight range of life permitting values would be of such low probability, that we can forget it.)

 

The only way of getting a sufficiently large number of possible local conditions is to postulate a multitude of universes. If the total number of universes is high enough, then the laws of probability determine that there must be one like ours. And here we are.

 

There is no actual theoretical reason to make this idea wrong. It's main drawback is simply that no-one wants to stick his neck out and say it is so.

 

We also face the scientific conundrum that there is no actual empirical evidence for a multiverse. The idea is purely speculative.

 

However, the way I see this, is that we are left with a choice between believing in a creator, or believing in the multiverse. Take your pick!

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Whap.

lambda is not the only constant these ideas apply to. If we added up all the constants of physics' date=' and noted their tight adherance to a narrow range of values that permit a universe that can develop life, then we have a universe whose probability is so low, that it might as well be zero.

 

On the face of it, this is very strong evidence for a creator, who made the universe according to tight specifications. For it to happen by chance would be almost inconceivable.

 

The anthropic principle is the way out of this conclusion. However, the idea of the universe having areas with different values of lambda in different parts of this universe makes no sense, since there are a number of other values that would also have to vary. The sum total suggests that to have even one solar system with the right values, requires a probability so low that we can ignore it.

 

( I have not calculated this. This is more intuitive, but I doubt any respected physicist would disagree. It was originally pointed out to me that there are six vital constants. eg. the ratio between the strength of gravity, and electromagnetic forces. To get all six within the tight range of life permitting values would be of such low probability, that we can forget it.)

[/quote']

 

This assumes that other outcomes are equally probably, which is untestable. It also assumes that "life" = "life as we know it." It's not evidence of anything, since the ideas involved are not scientific.

 

 

I don't think the article (I only scanned it) is as anti-anthropic as is claims. It's just giving an alternative to the multiverse hypothesis by sampling all values in time, rather than in some other dimension. But it doesn't counter the idea that if life is only going to arise for a small range of values of the fundamental constants, then you will only be alive to measure those constants when they have the right value. What it counters is the idea that if all values are possible, then the odds are small of gettng the value we have, since all values are eventually sampled.

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The AP is rapidly growing in popularity among string theorists, and this is the reason for the equally rapid appearance of competing theories.

It also assumes that "life" = "life as we know it." It's not evidence of anything, since the ideas involved are not scientific.

No, there are good reasons why "life as we know it" is the only form of life that is expected.

People who were there were surprised---it was 3 to 1 or some said 4 to one---they wanted physical reasons for why the constants are as they are---they didnt like the Anthrop explanation that this is just how it is because it allows life to exist and here we are so it had to be that way.

They don't like it because they are too arrogant to even consider that they should look for a good reason why we ARE the mechanism, so they pretend like the AP isn't an indication that we ARE THE MECHANISM, and this is how they justify looking elsewere...

 

... speaking of circular reasoned non-scientific lameness.

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Swansont.

It is not just 'life as we know it', it is any life at all. If the six constants do not fall within a small range of values (in total, a range of almost infinite improbability), then matter itself could not exist 'as we know it'.

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Swansont.

It is not just 'life as we know it'' date=' it is any life at all. If the six constants do not fall within a small range of values (in total, a range of almost infinite improbability), then matter itself could not exist 'as we know it'.[/quote']

 

And if matter existed in another form, how can you be sure life could not result? And again, I object to "infinite improbability," when it hasn't been demonstrated that e.g. the constants are independent of each other.

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And if matter existed in another form, how can you be sure life could not result? And again, I object to "infinite improbability," when it hasn't been demonstrated that e.g. the constants are independent of each other.

 

He should have noted that there is a cumulative runaway effect that rapidly compounds and accelerates. There is no happy medium. Either you have this universal configuration, or an expanding universe acclerates exponentially by orders of magnitude as it blows itself apart... period.

 

Recollapse is subject to the same cumulative runaway effect, as is global warming and the runaway greehouse effect, as this is counterbalanced by the long term tendency toward glaciation that is predicted by milankovitch models. (How many is that now, seven or seventy?)

 

I wonder what the odds are that 6(?!?) DEPENDENT or independent constants would all end up similarly eco-balanced near-exactly between diametrically opposing runaway tendencies.

 

Almost like there is no chance at all, huh?

 

And I guarantee you that it follows the least action principle, and not a freaking multiverse of possibilities...

 

*duh*

 

FYI:

I am now into my fourth year exclusively studying the anthropic principle and I seem to have an attitude, then it is because I am thoroughly disgusted with the mentality of the mainstream, not anybody in this forum. The reason for my disgust is a mindset that automatically assumes that an anthropic principle is born of geocentric arrogance, when Brandon Carter himself was very careful to state why this is NOT even the case!

 

He also clearly stated that the principle was put forth for the exact reason that STILL plauges honesty:

 

At the conference in Cracow, in 1973, Brandon Carter said that the AP respresents "a line of thought"[ "against exaggerated subservience to the Copernican Cosmological Principle"]

 

Carter was SO ON THE MONEY when he called this anti-centrist approach,"dogma", (which in its most extreme form led to the perfect cosmological principle".

 

Modern anticentrists are no different, and Carter's observation clearly indicates that they are STILL chasing the same "random" extreme... to the same exact dead-end!

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I wonder what the odds are that 6(?!?) DEPENDENT or independent constants would all end up similarly eco-balanced near-exactly between diametrically opposing runaway tendencies.

 

Almost like there is no chance at all' date=' huh?

[/quote']

 

It's a very different answer if they are dependent or independent.

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Life forming is not a random thing. It is based on the hydrogen proton. Hydrogen protons and hydrogen bonding is the basis for the properties of DNA, RNA, proteins and water. The metabolic energy of life is based on moving fixed protons, as C-H, into the mobile protons of water. Solar potential, indirectly stemming from fusion, allows the proton to become fixed to C via photosynthesis.

 

Life has evolved in the direction of increasing hydrogen proton potential. It is not cooincidental that the outer surfaces of neurons generate the highest proton potentials via their unusually high cation pumping rates. While the movement of positive charge, through water, within synapses and along neurons is an important part of the functioning of the brain. The mitochrondria, which are the power supplies of cells, pump hydrogen proton directly and use this potential to make ATP.

 

The random approach to life is only there because nobody wants to base life on the most significant thing in the universe, i.e., hydrogen protons.

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With respect to an accelerating universe if we include entropy into the picture things begin to add up. An entropy expansion is endothermic. What that means are sources of exothermic output is required to maintain the energy requirement. This is provided by gravity and fusion.

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It's a very different answer if they are dependent or independent.

 

Not so much, no... when you include the part that you cut where the anthropic coincidences are balanced between diametrically opposing runaway tendencies... because each additional coincidence exponentially compounds the implication that the mimimal entropy configuration is not a factor of luck... barring infinities, fairies, goblins, multiverses, and god.

 

Considering the *actual* number of similarly ecobalanced anthropic coincidences...

 

6, 60, 600... 6000... ?

 

~

 

Try energy-conservation as the good reason why the expanding universe is near perfectly flat... per the least action principle.

 

Figure out how and why we might be key players in the process as a cumulatively effective biocentric mechanism, which is what you get when the anthropic principle is correctly applied to other galaxies with planets that evolved at approximately the same time in the history of the universe.

 

That's the kind of causality-responsible physics that derives the configuration of our universe from *real* first principles, not mathematically idealized fairy-tails.

 

Cumulatively... not so special... like Brandon Carter told everyone that didn't listen:

 

"our situation is not necessarily central, but it is inevitably privileged to some extent".

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With respect to an accelerating universe if we include entropy into the picture things begin to add up. An entropy expansion is endothermic. What that means are sources of exothermic output is required to maintain the energy requirement. This is provided by gravity and fusion.

 

And the kicker to this is that we have no stabiltiy mechanism for explaining the low entropy configuration of our universe from any realistic model of turbulance generated structuring that we can come up with.

 

Anthropic/Biocentric preference is the only explanation that doesn't fall in the realm of mathematically supported conjecture.

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island.

I am not sure that I like your term 'biocentric'. If the multiverse theory is correct, then there is no reason why there cannot be an enormous number of universes with life, and a very small subset of the entire multiverse. Our universe and our Earth may be only a tiny part of the living portion of the multiverse.

 

It may be more correct of think of life as a chunk of existence way out, clear of the centre.

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Is there data to support multi-universes or is this just math conjecture? One needs to be careful with what is needed to close the math being used to define reality. Many attempt to justify the fudge factor by convincing others that this is reality so they can convince themselves. Show me some tangible proof.

 

If we look at the accelerated expansion, this makes no sense. If it is an accelerated expansion, doesn't that mean that the BB or creation occurred at a snail's pace? Or did the universe have haver an initial fast acceleration, followed by a slowdown and then all of a sudden a few years ago it begins to speed up again.

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Sunspot.

When we talk about the anthropic principle, or the multiverse, or a divine creator, we are way, way out in left field. We are in speculation country, otherwise known as neverneverland. Lets not talk about evidence. There ain't none!

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From the article linked to

Because a high lamda prevents the universe as we know it from forming, early cycles of the universe would have been void of galaxies, stars and life; only in later cycles, when lamda had decreased to a much smaller value, could matter coalesce to create the world we inhabit today.

 

And that is the crux of the matter - it is only universes that have these specific values that either last long enough, or do not “blow themselves apart” that actually survive to produce the intelligence that can question it.

 

Now where the “selection” comes in. Universes or if you prefer, sections of the Universe, whether that is in time, or space, are selected to survive by the fact that they have these specific values that allow them to survive. Now if these universes have the capability of producing more universes, possibly via black hole formation, then the ones that are better at producing others proliferate and produce more universes with just the right parameters. Just like evolution and natural selection really.

Therefore the Universe has evolved it’s current parameters, in a similar way to how life has evolved to suit those very parameters. If those parameters were very slightly different life would be very slightly different to suit. If those parameters were more than slightly different the universe would just not exist, but that does not stop it existing at another time or another place with those “just right” parameters.

 

It’s not anthropic selection - that we select it, just cosmological natural selection - the universes are selected dependant on what those parameters are, if they have them they survive and proliferate, they are also able to produce life to wonder about it.:)

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