Mysterious Cosmos [the anthropic principle]

Nature Magazine ^ | 06 August 2004 | Philip Ball

[PatrickHenry]

We are lucky to be alive. Extraordinarily lucky. So lucky, in fact, that some people can only see God's hand in our good fortune.

Creationists are fond of pointing out that if you mess with the physical laws of the Universe just a little, we wouldn't be here. For example, if the neutron were just 1% heavier, or the proton 1% lighter, or the electron were to have 20% more electrical charge, then atoms could not exist. There would be no stars, and no life.

But although creationists rejoice in the divine providence that has made the Universe exquisitely contrived to support life, science has long argued for an alternative explanation: the anthropic principle.

The theory has been supported by several leading physicists and astronomers, from Fred Hoyle to Steven Weinberg, who claim it reduces the mystery of our existence to a logical necessity.

Yet the whole idea is roundly trashed by Lee Smolin, a renowned quantum-gravity theorist at the Perimeter Institute in Waterloo, Canada. Smolin asserts, in a preprinted paper on Arxiv¹, that the anthropic principle is not a scientific theory at all, because it lacks the basic requirement of falsifiability. It is impossible to prove the anthropic principle wrong, hence it is outside the remit of science.

Circular argument

In truth, the idea always had an air of circularity about it. Crudely put, the anthropic principle states that our universe must look the way it does (that is, primed for life), because if it didn't, we wouldn't be here to argue about it.

But there is a little more sophistication to the idea, which has enabled some researchers to claim that they have put the principle to the test.

The argument usually goes something like this. Let us assume that our Universe is in fact just one of many. This collection of universes is called the multiverse, and its members cannot affect each other in any way. Assume also that physics, by which we mean the fundamental constants of nature, such as Planck's constant and the speed of light, differs more or less at random in each universe.

Most of these universes would be unable to support life. But if there were enough universes, a tiny fraction of them should have just the right parameters to give rise to a cosmos like ours.

Then, the anthropic principle asserts, the intelligent beings in those lucky universes would marvel at how their universe seemed fine-tuned for life, unaware of the countless other universes that remain barren forever. There is no need to invoke God to explain our precarious existence; chance alone suffices.

How one arrives at the multiverse is another matter, but there are possible mechanisms for that. For example, an extension of inflationary theory called eternal inflation suggests that new universes could continually blossom from tiny regions of a precursor universe².

Alternatively, new universes could be spawned by bouncing black holes. General relativity predicts that sufficiently large stars can collapse without limit under their own gravity to produce a point of space-time that is infinitely small and infinitely dense: the 'singularity' of a black hole. But the quantum-mechanical effects that must take hold at very small scales could in theory cause this collapse to reverse, so the black hole could rebound to form an entirely new universe, which would be a region of space isolated from the universe in which the black hole originally formed.

Put to the test

So in principle one can make new universes, and the anthropic principle could be true. But the real question is, does it actually predict or explain anything? This is what Smolin disputes. He thinks that not only has the idea failed to produce any testable predictions, it cannot do so even in principle.

That is quite a controversial view. Fred Hoyle, for example, used the anthropic principle to successfully predict the existence of a certain energetically excited state of the carbon nucleus. He argued that there would be no life as we know it without carbon, which can only be produced by stars. And he calculated that carbon atoms could only be made in stars in significant quantities if carbon possessed this particular state, which had never at that stage been observed.

Armed with his prediction, astronomers duly looked for the excited state, and found it. It sounds impressive. But Smolin points out that there is nothing anthropic about this reasoning. We know that carbon exists in the Universe irrespective of the existence of life, so life plays no essential role in the logic.

Look at it another way: suppose the predicted state of carbon had not been seen. Would we conclude that the anthropic principle was wrong? Clearly not, because carbon does, in fact, exist, and so do we. We would have to conclude instead that there must be some way of generating carbon other than the one Hoyle proposed, or that his calculations were wrong.

Much the same applies to a prediction of the value of the cosmological constant, made by Steven Weinberg in 1987. The cosmological constant was originally proposed by Einstein as a way of stopping his equations of relativity from predicting an expanding Universe (it was at that time assumed to be static). The idea of such a constant is now back in favour, because it might, this time, be used to rationalize the recently observed acceleration of the Universe's expansion.

Weinberg invoked the anthropic principle to argue that the constant could not be very large, or the Universe would expand too fast for galaxies, stars (or us) to form. A subsequent refinement of his argument predicted that the probability that the cosmological constant has the value suggested by current astrophysical observations is only around 10%.

In other words, the principle seems to make a prediction that, if not stunningly accurate, is certainly plausible. But again, Smolin says, "What is actually doing the work in the arguments is never the existence of life or intelligent observers, but only true observed facts about the universe, such as that carbon and galaxies are plentiful." Our own existence doesn't 'predict' anything.

"The anthropic principle is never going to give falsifiable predictions for the parameters of physics and cosmology," Smolin asserts.

No need for God

So are we forced back to the hypothesis of God? Not at all. Smolin adduces an alternative that, he claims, is scientifically falsifiable. He calls it 'cosmological natural selection'.

The most obvious scientific theory that accounts for a situation that, at first sight, seemed highly improbable is natural selection, points out Smolin. Darwin's idea abolished the need for the Reverend William Paley's heavenly 'watchmaker' to fashion the beautifully 'designed' products of biology.

Smolin believes that a similar principle could save us from making the same mistake about the Universe. This does not involve indulging in any "mysticism about living universes", he reassures us. Rather, he suggests that if there exists some process by which parent universes spawn new universes with small, random changes in their physical parameters, and if the characteristics of a universe determine how many progeny it produces, then fine-tuned universes like ours can arise by cosmological natural selection.

In particular, if new universes are produced by black-hole bounces, then universes in which stars (and thus black holes) can form are 'fitter' than others. After a period of time, you would expect the universes produced by this process to have a set of cosmological parameters that maximizes the number of black holes that can form.

That conclusion helps to explain why we are here, since universes in which complicated structures such as stars and black holes can form are also likely to be hospitable to life, Smolin argues. It also gives us a way to test the idea.

Smolin points to astrophysical measurements that we are able to make now, that could refute cosmological natural selection. For example, the existence of neutron stars with a mass greater than 1.6 times that of the Sun would scupper the idea. So, it could be wrong...but at least it's science.

[PatrickHenry]

However, there is one experimental result which, if it is upheld, may convince me of the practical utility of the anthropic principle.

You gonna tell us?

[tpaine]

Yes, yes, but why do you as an individual follow that rule? Why honor it? Why honor anything at all?

Because its in my own best interest, of course. I want others to honor my rights, therefor I honor their's. Amazingly simple concept, no?

How is it in your best interest?

READ my above answer, Will. You are going in circles.

Wouldn't you agree that discarding it when you stand to highly profit and gain with no chance of getting caught, or when your continence of life rides on discarding it is in your best interest?

No I don't Will. But your question tells me that you might. You've picked a strange way to make a point, imo.

What are you Will, some sort of nihilist? Why the pessimism for constitutional principle?

No, no, not a bit. It's a valid question for one with no perception of a higher power than man.

I perceive why YOU need to see a "higher power" Will. --- Please grant that I have a sense of honor without needing your god or his rules to guide it.

Constitutional principal does not have its eyes on your every minute wherever you are, and neither do any executive agencies thereof.

Of course it doesn't. We are free men and have free will. You would have it otherwise?

What exactly is honor to men that have no faith in other than the self-serving and clumsy law of the herd, easily avoided. What basis is there for conscience without God? Why bother?

Talk to your minister, kiddo. You have BIG problems about faith in your fellow man, imho.

[VadeRetro]

My argument has nothing to do with chemistry, or with the origin of life, or with the nature of any particular being.

The only kinds of being of which we have certain knowledge all have a strong basis in hardware.

Here is your argument.

It's basic metaphysics. If you say there is no God, you are saying that all beings are similar to those in our experience: i.e., produced by some efficient cause outside of themselves. If EVERY being is like that, then NO being would exist. But clearly, there are beings which exist. Thus, some being exists which is not caused by some being outside of itself.

Short form: You have to have a God [a being uncaused by other beings] because otherwise there wouldn't be any beings at all. There are beings, so there is a God.

Unsupported, circular, question-begging assertions. If it should turn out that the only beings of which we know have an abiotic origin, the whole thing falls apart. You probably don't particularly accept abiogenesis as the origin of life on Earth, but you can't rule it out in a syllogism that rules it out in one of the premises.

[tpaine]

Terrell wrote:

Also, in history, ancient and current, when that belief is discarded, much evil and mischief happens with the place in which it's discarded. The experiments in atheistic communism are good examples.

______________________________________


So it was the "discarding of religion" that caused problems in the USSR, not the fact that it was an economic imposition that requires brute force to keep in line because it's a completely illogical way to run a civilization?
You're picking out a single element from a big mess and trying to claim that the one element was the cause of all of the problems, except that you're not even trying to logically justify the connection.

-Dimensio-

_____________________________________


I see one 'element' that echos in history:


"The continuous disasters of man's history are mainly due to his excessive capacity and urge to become identified with a tribe, nation, church or cause, and to espouse its credo uncritically and enthusiastically, --
-- even if its tenets are contrary to reason, devoid of self-interest and detrimental to the claims of self-preservation.

We are thus driven to the unfashionable conclusion that the trouble with our species is not an excess of aggression, but an excess capacity for fanatical devotion."

-Arthur Koestler-

[PatrickHenry]

I wonder how you, of all the posters, can so easily bandy about the words 'good' and 'wicked'. ... I'm not really trying to flame you PH ..

Of course you're not. How could I get that impression? By the way, how's that family matter working out -- the one you freepmailed me about last month?

[Doctor Stochastic]

After all, they don't apply effort to debunk the patently absurd.

False. Scientists do spend quite a bit of effort in debunking the patently absurd. The problem is that the Proponents of the Absurd keep trying to get their ideas into the mainstream by use of politics and legal maneuvering because they are unable (or unwilling) to do science.

Of course course the Creationists scream loudly when their motives are questioned. Why should one give Creationists a pass? They seem bent on destruction of scientific inquiry as a method of gaining knowlege. What is their motive in denying simple chemistry or simple physics?

[Arthur McGowan]

My argument has absolutely nothing to do with living vs. non-living beings, or how life is transmitted, or how life arises from non-living matter, or anything whatever to do with life, or chemical processes, or astronomy, or geology, or any other science.

There are no scientific data that are relevant to my argument other than the observation that beings exist.

[Physicist]

You gonna tell us?

I thought you'd never ask. ;^)

Several years ago there was a measurement of a distant quasar by an Australian group that seemed to indicate that, for that quasar in the early universe, the value of the electromagnetic fine structure constant was different by one part in 10¹⁴. The possible interpretation that everybody latched onto was that the speed of light had changed since that time, by a really tiny amount.

Subsequent measurements have apparently ruled that out: last month, another group published measurements of a set of different quasars that rule out such an effect to one part in 10¹⁵.

But what if all of the measurements are correct? What if these tiny variations are due neither to experimental error or to the variation of physical constants over time, but due to their variation over space? Perhaps the physical constants differ from place to place, but the length scale over which they vary significantly is gigantically large, even compared to our Hubble volume.

It is known from the WMAP results that physical space extends MUCH farther than our Hubble volume. For all intents and purposes, space is infinitely large. Combine that with a slow variation of physical constants over space, and you end up with Hubble volumes that support life, and those that don't. Suddenly, subjective selection effects become decisive.

Not only that, but my expectation that fine-tuning problems are caused by physical principles is based upon the assumption that the (apparent) fine-tuning holds for all of physical reality. If that is demonstrated not to be true, then the anthropic principle has to hold sway. We'll just have to say that it's a big damn universe, and most of it is uninhabitable, but conscious minds can only ever see the habitable parts, however rare they may be.

[William Terrell]

"Power" does not imply excercising a level of control, nor does control imply a necessary expression through rules or laws. Power can be merely the potential to weild such control. Moreoever, even if power necessarily implies such rules and/or laws, it does not logically follow that such "rules and/or laws" are instructions for how humans are to live their lives.

Power, omniscient, omnipresent and omnipotent, can not exist without the impetus to exercise control. Guiding principles, laws and rules is the only way it can express itself.

When we talk of the higher power we are talking about, and the one you are steadfastly against, we are talking about sovereignty, laws and rules. We are also talking about a creative force that would be behind Creation as we know it, including us.

A Creator necessarily cares how its creatures follow the pattern created, and there definitely is a pattern. Evolutioners are working hard to find some explanation for it.

A higher power who creates nothing and cares about nothing is not higher than mankind, and who does nothing with its creative power is not, by definition, a higher power in the sense with which I spoke in my initial post.

Yes, civilizations throughout history have believed in a form of a "higher power". And these beliefs have varied wildly amongst the civilizations and amongst the centuries. That's not evidence, that's argument ad numerum combined with argument ad antiquitum.

It is evidence that there is a higher power that all men sense, even after the explosion of science and material exploration.

What percentage of the US do you think are atheists (adults, of course) today? What percentage in 1950? The percentages will have increased.

If the increase is toward enlightenment, then what are the discoveries and truths that drove that enlightenment? And in what material way have the natures of human beings changed to realize that enlightenment?

So it was the "discarding of religion" that caused problems in the USSR, not the fact that it was an economic imposition that requires brute force to keep in line because it's a completely illogical way to run a civilization?

No, it was a discarding of the natural faith in a higher power than man that allowed the base animal instincts to hold sway.

Materialism, my friend. To satisfy the desires of the body's instinct for survival in a condition of no one to answer to if not caught at it. Out of that attitude, comes evil and mischief.

Oh, it was a very logical civilization, using the given of the absence of a higher power. Logic and materialism was all it had for guidance. That was it's problem and the reason it took brute force to hold it together.

You're picking out a single element from a big mess and trying to claim that the one element was the cause of all of the problems, except that you're not even trying to logically justify the connection.

The very disrespect for human life outside one's own and those whom one loves (them being painful to lose), because there is no positive and assumed intrinsic value to human life outside it's ability to produce for whomever is in control, is the common thread running through all of them.

You're assuming your conclusion, another logical fallacy.

When human beings congregate there is loss and death as well as prosperity and joy. In all the instances of an atheistic based system the loss and death is an order of magnitude greater, and the prosperity and joy that same order less, than the instances of systems founded on the belief and reverence for a higher power.

My conclusion is based on that observation.

I'm saying that you are justifying your claims regarding the attributes of a "higher power" by constructing your own, personalized definition of "higher power" and pointing to it.

A higher power than man, one out of which creation sprang (using whatever mechanism) necessitates some standard and commonly held principals. Nothing personalized about it.

[VadeRetro]

There are no scientific data that are relevant to my argument other than the observation that beings exist.

Everything I said about your argument still goes. Circular, question-begging, and useless.

[William Terrell]

This is tpaine's conversation. If you have some argument, frmail your consideratons to him and let him post them to me.

[Godfollow]

Put it to the death test...
I'll believe in God and his Son Jesus as my savior..
You believe in another religion, or no religion...
And when we die, lets see where we end up...
Until then, lets us agree to make this world a place where Justice and Mercy direct the events of men...

[William Terrell]

READ my above answer, Will. You are going in circles.

You said, "Because its in my own best interest, of course. I want others to honor my rights, therefor I honor their's.

The last sentence is false. Other's don't honor your rights because you honor theirs. So, how is it in your best interests?

No I don't Will. But your question tells me that you might. You've picked a strange way to make a point, imo.

I asked, "Wouldn't you agree that discarding it when you stand to highly profit and gain with no chance of getting caught, or when your continence of life rides on discarding it is in your best interest?

I stress "you" because you have no foundation to buttress, and no source for, the extreme amount of moral strength it takes to resist a mighty temptation when your act would go unnoticed and unwitnessed.

We're not talking about me. I have that faith in a higher power.

I perceive why YOU need to see a "higher power" Will. --- Please grant that I have a sense of honor without needing your god or his rules to guide it.

No. I don't grant that. It is easy to have honor based on a mere philosophical belief when little is at stake, but not possible when extreme pleasure, extreme security and basic survival are is at stake.

Of course it doesn't. We are free men and have free will. You would have it otherwise?

Then what's to keep you honest in the darkness? The constitution, manmade laws, without the constable around? Honor? Why do you need honor for your personal survival?

Talk to your minister, kiddo. You have BIG problems about faith in your fellow man, imho.

I'm talking to you. You claim to have morals and honor, and ethics, in a medium where human life is just an freak accident and has value only what you and the manmade law assign it.

Each time I ask a hard question, you attempt to throw it back on me. I hold faith in a higher power than man and realize through that common heritage of all, every human life has intrinsic value.

So, let avoid that tactic, if you please.

[William Terrell]

Post your last comments to me, alone, and I'll respond. Very easily. Thanks.

[PatrickHenry]

It is known from the WMAP results that physical space extends MUCH farther than our Hubble volume. For all intents and purposes, space is infinitely large. Combine that with a slow variation of physical constants over space, and you end up with Hubble volumes that support life, and those that don't. Suddenly, subjective selection effects become decisive.

If these variable regions are outside our Hubble volume -- except for one anomalous quasar -- then we can't observe them or conduct experiments about them, so in effect this isn't all that different from multiple universes, one of which (ours) has the Goldilocks set of constants.

[Arthur McGowan]

My argument is not circular. You have characterized it as circular, but you have not shown precisely wherein it is circular.

[js1138]

Which interpretation of God do you believe the article challenges?

Sorry to be so long responding. My pings are overwhelmed by political news.

1. Any interpretation that would require continuous divine intervention or adjustment to natural laws.

2. Most interpretations which suggest that every aspect of the unfolding of creation is "known in advance".

[longshadow]

anomalous placemarker

[PatrickHenry]

What if these tiny variations are due neither to experimental error or to the variation of physical constants over time, but due to their variation over space? Perhaps the physical constants differ from place to place, but the length scale over which they vary significantly is gigantically large, even compared to our Hubble volume.

Layman's conjecture. You may freely ignore the following:
That would mean that space itself (whatever that is) varies as to the physical laws that apply within it. I don't see it. I think there needs to be a universal mechanism which causes such regional variations. The only thing that comes to mind (my mind anyway) is Mach's Principle. If the distribution of distant objects, which imparts inertia to mass (at least in the pre-Higgs particle mode of thinking), were significantly different in some distant domain, then yes, it could appear that different laws were in effect.

[tpaine]

Yes, yes, but why do you as an individual follow that rule? Why honor it? Why honor anything at all?

Because its in my own best interest, of course. I want others to honor my rights, therefor I honor their's. Amazingly simple concept, no?

How is it in your best interest?

READ my above answer, Will. You are going in circles.

The last sentence is false. Other's don't honor your rights because you honor theirs. So, how is it in your best interests?

No, will, not false. That's how our Constitutional system works.
As I say, you have problems believing that, & should see a professional, imo.

___________________________________

Wouldn't you agree that discarding it when you stand to highly profit and gain with no chance of getting caught, or when your continence of life rides on discarding it is in your best interest?

No I don't Will. But your question tells me that you might. You've picked a strange way to make a point, imo.

I asked, "Wouldn't you agree that discarding it when you stand to highly profit and gain with no chance of getting caught, or when your continence of life rides on discarding it is in your best interest? I stress "you" because you have no foundation to buttress, and no source for, the extreme amount of moral strength it takes to resist a mighty temptation when your act would go unnoticed and unwitnessed. We're not talking about me. I have that faith in a higher power.

Yes will, I'm talking about you, -- and your incredible hubris in assuming that I haven't the "moral strength" that you puff yourself up to possess. Get real.

What are you Will, some sort of nihilist? Why the pessimism for constitutional principle?

No, no, not a bit. It's a valid question for one with no perception of a higher power than man.

I perceive why YOU need to see a "higher power" Will. --- Please grant that I have a sense of honor without needing your god or his rules to guide it.

No. I don't grant that. It is easy to have honor based on a mere philosophical belief when little is at stake, but not possible when extreme pleasure, extreme security and basic survival are is at stake.

Again, you seem to be claiming a knowledge of my character you simply cannot possess. Very stupid ploy.

Constitutional principal does not have its eyes on your every minute wherever you are, and neither do any executive agencies thereof.

Of course it doesn't. We are free men and have free will. You would have it otherwise?

Then what's to keep you honest in the darkness? The constitution, manmade laws, without the constable around? Honor? Why do you need honor for your personal survival?
What exactly is honor to men that have no faith in other than the self-serving and clumsy law of the herd, easily avoided. What basis is there for conscience without God? Why bother?

Talk to your minister, kiddo. You have BIG problems about faith in your fellow man, imho.

I'm talking to you. You claim to have morals and honor, and ethics, in a medium where human life is just an freak accident and has value only what you and the manmade law assign it.

And you claim I don't have "morals and honor, and ethics"? On what basis? You just 'know'?

Each time I ask a hard question, you attempt to throw it back on me. I hold faith in a higher power than man and realize through that common heritage of all, every human life has intrinsic value. So, let avoid that tactic, if you please.

Yep. You just claim to 'know'.
You have faith in your moral superiority, because you claim to have faith, -- a ludicrous circular argument. -- Only valid in your dreams..