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Author Topic:   schrodinger's backside
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 16 of 45 (385891)
02-17-2007 9:24 PM
Reply to: Message 15 by AZPaul3
02-17-2007 7:50 PM


Re: A fine-tuned Universe?
I have an issue with requiring an observation by any kind of sentient being to bring the Universe into existence. The Universe existed from (we presume) the big bang on, well prior to the materials necessary to create and sustain life. No sentience needed for the Universe to exist.
The Universe is (or appears to be) a 4d entity. When we say the Universe contains sentient life, it is not necessary to specify at what specific (4d) coordinates such sentience is located.
The Universe did not "begin" to exist at the Big Bang... the Universe just exists. Existence is not a property of time: time is a property of existence. And given that we have very lttle clue as to what existence is, it is difficult to make statements as absolute as yours.
For a Universe to be said to be "fine-tuned" for life, in my opinion, requires an abundance of life as evidence of such
Yes, it is most definitely your opinion. But I have already pointed out that your reasoning is not sound. Tuning to the point of abundance of life may be 1) undesirable by the active agent 2) unnecessary by the WAP selective process 3) incompatible with the natural constraints placed upon the parameters.
My point being that if some insist that the Universe was/is in some why fine-tuned by whatever mechanism, the preponderance of the evidence at this time indicates the fine-tuning produced prodigious stellar objects not life. Life, apparently, was an incidental aftereffect.
Given what we know of the physics of life, stellar abundance is an absolute necessity, even for a marginal content of sentient life. The two are most certainly not independent.
Further, I find the very idea of any kind of "fine-tuning" untenable
Fine-tuning via a WAP mechanism is actually the one way out of positing either Design or some more meta-physical connection between ourselves and the fundemental nature of the Universe.
outside of the smallest distances and the smallest timesc can any particle avoid the environment in the reality of this universe?
Well, you're forcing me into a corner - of large distances and long time-scales - difficult. But give me any of the other three options and no problem (large distance over small timescales, small distances over long timescales, etc) I sometimes entertain the idea of preserving a long-lived macroscopic quantum state in a gravitational Faraday cage - say a planet sized hollow sphere...
And since distance is irrelevant to entanglement can you really say it extends the quantum realm into classical distances?
I'm not sure I understand you... I would say that as distance is irrelevant to entanglement it is obvious that the quantum realm extends into "classical" distances.

This message is a reply to:
 Message 15 by AZPaul3, posted 02-17-2007 7:50 PM AZPaul3 has not replied

Replies to this message:
 Message 17 by sidelined, posted 02-17-2007 9:40 PM cavediver has replied

  
sidelined
Member (Idle past 5908 days)
Posts: 3435
From: Edmonton Alberta Canada
Joined: 08-30-2003


Message 17 of 45 (385892)
02-17-2007 9:40 PM
Reply to: Message 16 by cavediver
02-17-2007 9:24 PM


Re: A fine-tuned Universe?
cavediver
Existence is not a property of time: time is a property of existence.
I am curious as to the property of time if there is no beginning.What is the connection between motion of 3-d space and the property called time?
If existence has "always" had motion of some sort is there any real difference between momentum and time?

This message is a reply to:
 Message 16 by cavediver, posted 02-17-2007 9:24 PM cavediver has replied

Replies to this message:
 Message 18 by cavediver, posted 02-18-2007 5:40 AM sidelined has replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 18 of 45 (385914)
02-18-2007 5:40 AM
Reply to: Message 17 by sidelined
02-17-2007 9:40 PM


Re: A fine-tuned Universe?
I am curious as to the property of time if there is no beginning
This is one of the big conceptual difficulties with GR and space-time physics. Infinities don't mean that much. I still visualise a universe with no temporal beginning and end as a compact object I can hold in my hand - even when the spatial dimensions are infinite as well The dimensions are properties of the universe and the parameter space of the dimensions are properties of the dimensions - so whether T spans from 0 to Tmax, or from -inf to +inf, doesn't really concern me when I'm considering the big picture... they're just labels. It's only when we zoom in to look at the geometry of the universe, that the diferent parameter possibilities make a significant difference.

This message is a reply to:
 Message 17 by sidelined, posted 02-17-2007 9:40 PM sidelined has replied

Replies to this message:
 Message 19 by sidelined, posted 02-18-2007 10:08 AM cavediver has replied

  
sidelined
Member (Idle past 5908 days)
Posts: 3435
From: Edmonton Alberta Canada
Joined: 08-30-2003


Message 19 of 45 (385935)
02-18-2007 10:08 AM
Reply to: Message 18 by cavediver
02-18-2007 5:40 AM


Re: A fine-tuned Universe?
cavediver
I guess what I am trying to wrap my head around is if time is not just an illusion produced by momentum of matter through space. In the same way that the sun has no real edge but only appears to have one because it is an illusion produced by properties of light propagation.

This message is a reply to:
 Message 18 by cavediver, posted 02-18-2007 5:40 AM cavediver has replied

Replies to this message:
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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 20 of 45 (385942)
02-18-2007 12:03 PM
Reply to: Message 19 by sidelined
02-18-2007 10:08 AM


Re: A fine-tuned Universe?
I guess what I am trying to wrap my head around is if time is not just an illusion produced by momentum of matter through space
I guess my thought is that SR/GR works to such an extraordinary degree, and relativity shows us that time is inextricably linked with space in quite a geometrically non-trivial way. We now have a harder time separating the two - we can't simply visualise 4d space-time as an ordering of 3d events, which we can with Newtonian cosmology. I like Barbor's work at thsi point, although I think that our own illusion of time develops at a much a higher level that he suggests. Otherwise I have a hard time reconciling his ideas with GR.

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Replies to this message:
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crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 21 of 45 (385944)
02-18-2007 12:18 PM
Reply to: Message 14 by cavediver
02-16-2007 2:47 PM


Re: A fine-tuned Universe?
(This isn't an exact quote; I'm compressing your conversation a little.)
If these constants were fine-tuned, by God or Nature, for the evolution of life then we should see prodigious life throughout the galaxy
Tuning to the point of abundance of life may be 1) undesirable by the active agent 2) unnecessary by the WAP selective process 3) incompatible with the natural constraints placed upon the parameters.
This is like asserting that chopsticks are "fine-tuned" for eating tomato soup. Sure, you could do it (just dip 'em in and lick), and it's better than nothing; but obviously what's fine-tuned for soup is a spoon.
Your response is, to me, as nonsensical as saying "but if you wanted to eat tomato soup with chopsticks, and if for some reason spoons were physically impossible, well, then, chopsticks would be fine-tuned for eating soup." It doesn't make any sense to me - it's the "fallacy of the looming caveat", if I can coin a term. I can imagine what a universe fine-tuned to be the very cradle of life would be like; and a universe where life clings tenuously to a blue planet of maybe one to a galaxy, like lichen on a rock surrounded by desert, isn't it.

This message is a reply to:
 Message 14 by cavediver, posted 02-16-2007 2:47 PM cavediver has replied

Replies to this message:
 Message 22 by cavediver, posted 02-18-2007 12:46 PM crashfrog has replied
 Message 26 by SophistiCat, posted 02-18-2007 8:40 PM crashfrog has replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 22 of 45 (385947)
02-18-2007 12:46 PM
Reply to: Message 21 by crashfrog
02-18-2007 12:18 PM


Re: A fine-tuned Universe?
This is like asserting that chopsticks are "fine-tuned" for eating tomato soup
Out of the parameter space of implements of the order of 0.1-1m in size, then I would agree. If the parameter space is of any conceivable object, on the scale of Planck length to radius of observable universe, I would say your chop-stick is incredibly fine-tuned. And observing over such a scale, I would really not be able to distinguish between the chop-stick and the soup-spoon.
I can imagine what a universe fine-tuned to be the very cradle of life would be like
Perhaps, but that is not a fine-tuning of THIS universe. As I mention in (3), it is possible that no amount of tuning will create prodigious life within this universe.
Even if such a tuning is possible, this says nothing of (2)... given the entire possible parameter space, it is easy to imgaine "no life" vastly dominating, followed by some very small measure of "sparse-life" and finally "abdundant-life" would be some microscopic corner of the space, barely visible. If we then take random samples of this parameter space, "no life" universes are discounted as they are not observed. We are left with "sparse-life" and "abundant-life", and the probability of drawing from the latter is fairly close to zero.
IF our (observable) universe is one of an essentially infinte number of trials with varying parameters, then the overwhelming odds are that we inhabit a universe with sparse-life.

This message is a reply to:
 Message 21 by crashfrog, posted 02-18-2007 12:18 PM crashfrog has replied

Replies to this message:
 Message 23 by crashfrog, posted 02-18-2007 1:45 PM cavediver has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 23 of 45 (385959)
02-18-2007 1:45 PM
Reply to: Message 22 by cavediver
02-18-2007 12:46 PM


Re: A fine-tuned Universe?
Out of the parameter space of implements of the order of 0.1-1m in size, then I would agree. If the parameter space is of any conceivable object, on the scale of Planck length to radius of observable universe, I would say your chop-stick is incredibly fine-tuned.
But that's my point, exactly. The universe isn't fine-tuned; what's being fine-tuned are your assumptions, leading to a conclusion of fine-tuning.
As I mention in (3), it is possible that no amount of tuning will create prodigious life within this universe.
Right, but an argument from what isn't known doesn't get very far with me. Sure, it's possible. It's possible the alternative is true, as well.
All that, to me, adds up to too much uncertainty to conclude fine-tuning.

This message is a reply to:
 Message 22 by cavediver, posted 02-18-2007 12:46 PM cavediver has replied

Replies to this message:
 Message 24 by cavediver, posted 02-18-2007 2:02 PM crashfrog has not replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 24 of 45 (385961)
02-18-2007 2:02 PM
Reply to: Message 23 by crashfrog
02-18-2007 1:45 PM


Re: A fine-tuned Universe?
Right, but an argument from what isn't known doesn't get very far with me. Sure, it's possible. It's possible the alternative is true, as well.
Maybe, but would you like to suggest how? Let's take a number of the most commonly considered parameters - the fine structure constants, G, masses of the particles of the Standard Model, number of families in the Standard Model, Lambda, etc. Now how would you go about arranging those to make a Universe full to the brim of life?
I'm not sure you are on the same page as to what we call fine-tuning in phsyics - we are talking about getting a usable universe. One that hangs around for longer than a few seconds-to-years. One that doesn't expand so fast that all there is is ionised hydrogen. One that has its fine structure constants such that atoms are stable, that stars can burn, etc, etc. This is what we need for life.
If all these parameters can vary from universe to universe (or area of universe to area) then we have our explanation in the WAP. The universe appears finely tuned because we only see those universes that support us.

This message is a reply to:
 Message 23 by crashfrog, posted 02-18-2007 1:45 PM crashfrog has not replied

  
GDR
Member
Posts: 6202
From: Sidney, BC, Canada
Joined: 05-22-2005
Member Rating: 1.9


Message 25 of 45 (385978)
02-18-2007 5:17 PM
Reply to: Message 20 by cavediver
02-18-2007 12:03 PM


Re: A fine-tuned Universe?
cavediver writes:
I guess my thought is that SR/GR works to such an extraordinary degree, and relativity shows us that time is inextricably linked with space in quite a geometrically non-trivial way. We now have a harder time separating the two - we can't simply visualise 4d space-time as an ordering of 3d events, which we can with Newtonian cosmology. I like Barbor's work at thsi point, although I think that our own illusion of time develops at a much a higher level that he suggests. Otherwise I have a hard time reconciling his ideas with GR.
Julian Barbour as I understand it contends that time as such doesn't even exist but is only the way that we perceive change. Here is a link to a site that includes a discussion with Barbour and a review of his book.
Julian Barbour
Amongst the many things that I don't understand in all of this is how his picture of how time represents change is consistent with GR which shows that time, (as represented by change) is different for each one of us. It seems to me that his theory requires a more Newtonian idea of time. I know this guy is more than smart enough to have figured this out but I still can't see how you can have every moment of time an eternal now when my nows are not the same as anyone else's nows.

Everybody is entitled to my opinion.

This message is a reply to:
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SophistiCat
Junior Member (Idle past 4867 days)
Posts: 13
From: Moscow
Joined: 02-03-2007


Message 26 of 45 (385994)
02-18-2007 8:40 PM
Reply to: Message 21 by crashfrog
02-18-2007 12:18 PM


Re: A fine-tuned Universe?
Greetings!
(Gak! This is a very awkward forum setup. Why no automatic quoting?)
This is like asserting that chopsticks are "fine-tuned" for eating tomato soup. Sure, you could do it (just dip 'em in and lick), and it's better than nothing; but obviously what's fine-tuned for soup is a spoon.
The essential property of fine-tuning, in the common usuage of the term, is not the abundance of the fine-tuned feature, but rather its delicacy. In the instance of cosmic fine-tuning, the case being made is that for any life to be possible (let alone abundant), a number of fundamental constants must lie within a tight range (in some special sense of "tight range" - this aspect is actually a bit problematic).
This in itself, of course, is not an argument for design. The full argument must be put in terms of (Bayesian/subjective/personal) probabilities. This seems to be the difficult part: I have yet to see a sound fine-tuning argument for design. Usually the proponents of the argument try to appeal to intuition by bringing up semi-irrelevant analogies, such as the firing squad.
My intuitive take on it is that there is nothing particularly surprising about our universe being "fine-tuned" for some delicate features, such as life. Life is delicate because it is contingent on a great many prerequisits. Knock out one - and life as we know it becomes impossible. But life is not unique in that respect. There ought to be any number of delicate features in any conceivable universe, including our own - as long as they are complex and long-lived enough (a universe that collapses into a black hole immediately after its birth would not have many features, delicate or not). Which is to say, many, if not all universes will be "fine-tuned" for one thing or another - most likely, a great many things. The mere fact that a complex, long-lived universe has some highly contingent, and therefore delicate, features is not in itself surprising, and therefore does not cry out for an explanation.

This message is a reply to:
 Message 21 by crashfrog, posted 02-18-2007 12:18 PM crashfrog has replied

Replies to this message:
 Message 27 by cavediver, posted 02-18-2007 9:01 PM SophistiCat has replied
 Message 28 by crashfrog, posted 02-19-2007 12:23 AM SophistiCat has replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 27 of 45 (385996)
02-18-2007 9:01 PM
Reply to: Message 26 by SophistiCat
02-18-2007 8:40 PM


Re: A fine-tuned Universe?
The mere fact that a complex, long-lived universe has some highly contingent, and therefore delicate, features is not in itself surprising, and therefore does not cry out for an explanation.
You are missing the point. It is the complex, long-lived universe that is "surprising" and which requires an explanation. You actually provide the very one I have expounded...
Which is to say, many, if not all universes...
Namely, the assumption of multiple universes - which then allows us to appeal to the WAP. Without that assumption, we are left looking for an alternative explanation...
Welcome to EvC, BTW

This message is a reply to:
 Message 26 by SophistiCat, posted 02-18-2007 8:40 PM SophistiCat has replied

Replies to this message:
 Message 29 by SophistiCat, posted 02-19-2007 12:25 AM cavediver has replied

  
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 28 of 45 (386012)
02-19-2007 12:23 AM
Reply to: Message 26 by SophistiCat
02-18-2007 8:40 PM


Re: A fine-tuned Universe?
The essential property of fine-tuning, in the common usuage of the term, is not the abundance of the fine-tuned feature, but rather its delicacy. In the instance of cosmic fine-tuning, the case being made is that for any life to be possible (let alone abundant), a number of fundamental constants must lie within a tight range (in some special sense of "tight range" - this aspect is actually a bit problematic).
Well, sure. We don't know how wide that range actually is, or even if these constants aren't simply derivative values of some simpler, base variable.
And to say that "life as we know it becomes impossible" may be true, but it's hardly significant - it's completely unknown how many other forms of life there could be that we don't know, and what kind of lifeforms could be supported by other "settings" for these universal options.
We just don't know how contingent any of these supposedly tuned values actually are. Maybe there's a set of physical laws that governs how universes can be created and restricts the settings to certain outcomes. Or maybe there's not. Who knows? In the face of all that ignorance does it make sense to talk about tuning? I don't see that it does.

This message is a reply to:
 Message 26 by SophistiCat, posted 02-18-2007 8:40 PM SophistiCat has replied

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SophistiCat
Junior Member (Idle past 4867 days)
Posts: 13
From: Moscow
Joined: 02-03-2007


Message 29 of 45 (386013)
02-19-2007 12:25 AM
Reply to: Message 27 by cavediver
02-18-2007 9:01 PM


Re: A fine-tuned Universe?
You are missing the point. It is the complex, long-lived universe that is "surprising" and which requires an explanation. You actually provide the very one I have expounded...
But this is not the point that is usually made by fine-tuning proponents. The argument being made concerns the habitability of the universe. The argument, as I said, is rarely developed into a robust probability argument, and instead appeals to intuition. Naturally, the fact that our universe is habitable is a lot more "interesting" than it merely being large or complex or long-lived. A barren, though otherwise feature-rich universe does not excite imagination as much as a life-bearing one. We are naturally biased that way.
As for the point that you wish to make, is it a fact that complex, long-lived universes are rare in the parameter space of the fundamental constants? I don't recall this argument being made, because, as I said, most people are more interested in the more specific class of habitable universes.
Which is to say, many, if not all universes...
Namely, the assumption of multiple universes - which then allows us to appeal to the WAP. Without that assumption, we are left looking for an alternative explanation...
No, we do not need to make assumptions about an actual multiverse. Though I personally think that such a hypothesis would still be more probable than the one involving some kind of cosmic Designer, it is simply unnecesary to invoke it.
Welcome to EvC, BTW
Thanks!

This message is a reply to:
 Message 27 by cavediver, posted 02-18-2007 9:01 PM cavediver has replied

Replies to this message:
 Message 32 by cavediver, posted 02-19-2007 5:06 AM SophistiCat has replied

  
SophistiCat
Junior Member (Idle past 4867 days)
Posts: 13
From: Moscow
Joined: 02-03-2007


Message 30 of 45 (386020)
02-19-2007 12:47 AM
Reply to: Message 28 by crashfrog
02-19-2007 12:23 AM


Re: A fine-tuned Universe?
Well, sure. We don't know how wide that range actually is, or even if these constants aren't simply derivative values of some simpler, base variable.
One apparent problem is that if we allow the range of constants to be infinite (since we don't know of any natural bounds at least for some of them), the probabilility becomes not just small, but exactly 0. But this invalidates the fine-tuning argument (FTA), since it requires the probabilities to be small but non-zero. Besides, the probability in this case doesn't depend on the actual habitable range, as long as it is finite (this is known as "coarse-tuning" problem). But there are some clever arguments that attempt to get around this issue.
And as you note, it is quite possible that the constants that are independent in the present models will be made dependent in some future "theory of everything". Whether fine-tuning will be true in such a theory is anyone's guess.
It is also possible that there are plenty of as-yet unexplored ranges and combinations of constants where some kind of life would be possible.
Another thing is that there is no reason why only the constants (which are themselves somewhat arbitrary) are allowed to vary and not the form of the laws. I am not aware of anyone trying to formulate the FTA for the fundamental equations.
And to say that "life as we know it becomes impossible" may be true, but it's hardly significant - it's completely unknown how many other forms of life there could be that we don't know, and what kind of lifeforms could be supported by other "settings" for these universal options.
Well, under some obvious conditions, such as when the universe collapses into a black hole, it is difficult to imagine any kind of life developing.
We just don't know how contingent any of these supposedly tuned values actually are. Maybe there's a set of physical laws that governs how universes can be created and restricts the settings to certain outcomes. Or maybe there's not. Who knows? In the face of all that ignorance does it make sense to talk about tuning? I don't see that it does.
Yes, there is enough uncertainty that even if the FTA was valid (which it isn't), the payoff for the theist would probably be nugatory.

This message is a reply to:
 Message 28 by crashfrog, posted 02-19-2007 12:23 AM crashfrog has not replied

  
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