L. Susskind -- The "Megaverse"

[TheRedWorm]

To be consistent with your own reasoning, you should doubt my hypothesis. You have never seen me attempt a shot at any range. You have no data on me. You have no way of knowing how "odd" I am.

Not entirely true. You obviously know enough about general shooting to know that the shot you propose is extremely difficult for even veteran shooters to accomplish. So, while I may not know anything about your marksmanship to say definitively that you couldn't make the shot, it is not entirely unreasonable to say that it would be one hell of a shot if you did.

All you have is some indirect data about shooting. But by your reasoning, that should be dismissed. Nothing will suffice except direct observation of my shooting ability, by your reasoning. That is the inescapable point of your repeated requirement of a database of universes to compare this one to, presumably in order to test for the herring-like 'oddity'.

Well, that's not entirely accurate, is it? We know that there are other shooters in this world. We know what kind of weapons exist, as well as their ballistic characteristics.

And, why is it so bad that I am asking for a counter example of a universe that's laws are different in order to say that this one is somehow unique, or what ever word you would rather use? Isn't that the impetus for discovery? Forget what we can speculate about other universes, let's go out and try to find the buggers. It may never happen, which is why we can't say, definitively, that we are unique, sepcial, odd, mundane, or a dime for 10 billion. We just don't know, and need to fine out more. All I am advocating is to not call so-called fine tuning a problem when we have little to not evidence that it is fine tuned at all.

I don't need to plop myself on a different planet to give you a strawman to beat up. It is not my job to give you a strawman to beat up. My job is to prevent you from (very predictably) substituting an altered analogy for my analogy and then beating up the altered analogy.

However, I do have an idea how the aliens would likely react, after being provided the information we both have. After I showed them the rifle, explained how it works, and explained what I proposed to attempt, they would agree I couldn't do it. ...<snip>...

How do you know they'd even listen or care? Or are you just assuming that they would?

 

[Perpetual Student]

So if someone is claiming that there is a fine-tuning problem in the sense that we must explain why we have the odd values of different physical constants that we do, they are mistaken. If someone is speaking of the fine-tuning problem in the sense that we have no explanation as to why we have one value rather than another, then this seems acceptable.

The above seems to be at the core of the different perspectives we have on this. I don't think we need to claim they are "odd" in order to want an explanation for them. In the absence of some universal law of everything from which we could derive all the fundamental constants, they remain unexplained -- is that "odd"?

You also said:

Fine-tuning arguments are bad science when fine-tuning is assumed and inferences are drawn from this assumption. Fine-tuning arguments are bad when they are arguing from a weak anthropic argument to a grander claim of oddity; given that life has to fit into whatever environment we find it in, we cannot find it odd that life fits into whatever environment we find it in. That the universe might be just right for one type of life does not mean that there might be other kinds of life that might be fine in other kinds of universes. Fine-tuning arguments are, in principle, fine when physical evidence establishes that there is some reason to suppose that the current physical phenomena that we observe in our region of the universe are not those that we should see.

I don't think fine-tuning is assumed as much as it is observed. I agree that there is no reason to assume some other combination of the constants could not result in some other kind of universe that might include life and even intelligence. However, I'm at a loss to understand why you think fine-tuning requires some reason to believe the constants are not "those that we should see." Asking why they are what they are is enough. It is a perfectly good scientific question and remains unexplained. The fact that these constants result in the universe we see (and to our species) makes the question even more compelling.
I also agree that " Fine-tuning arguments are bad when they are arguing from a weak anthropic argument to a grander claim of oddity." I don't believe fine-tuning arguments necessarily do that. The fact that a change in just one of many constants, say the fine-structure constant, would dramatically change the universe is enough to motivate us to ask, why is it what it is? Could it be different under some other initial conditions for the universe? Did it come about randomly? Is it inevitably the only value it could be? These are the questions that define fine-tuning. We do not need to regard α as "odd" to ask these questions.

Getting back to the OP, I do see the megaverse conjecture as a possible answer to these questions.

 

[Toontown]

Not entirely true. You obviously know enough about general shooting to know that the shot you propose is extremely difficult for even veteran shooters to accomplish.

I see. You have no data on my shooting ability, so you're settling for indirect inference.

So, while I may not know anything about your marksmanship to say definitively that you couldn't make the shot, it is not entirely unreasonable to say that it would be one hell of a shot if you did.

So you do understand the concept of recognizing an outcome as unlikely, even if you don't have a data base to prove it empirically.

Well, that's not entirely accurate, is it? We know that there are other shooters in this world. We know what kind of weapons exist, as well as their ballistic characteristics.

And 'we' also know a good deal more about the nature of this universe than you seem to want to acknowledge.

An extensive understanding of the nature of this universe is required to even be able to predict the existence of the universal Higgs field, understand how to detect it, and build the huge, expensive machine to detect it with.

I think they were expecting it to look ludicrously fine tuned, and they apparently weren't surprised. But now there's kind of a 'what now?' look going around. Now that they know for a fact that the thing is tuned to 120 decimal places - exactly what is required to cancel all the other known stuff and have a universe with stars and planets that the likes of us can live on....

Well, what now?

Well, as I see it, the good news is, it's not really fine tuning. It's just telling us anthropic reasoning really works if you use it right - when you know what a something has to be for us to be here, then you know what it's going to be before you see it. Because we're here.

And, why is it so bad that I am asking for a counter example of a universe that's laws are different in order to say that this one is somehow unique, or what ever word you would rather use?

Well, at least you aren't asking for much. Just a little trip to another universe in order to test it's laws to see if they are different.

But I was hoping it wouldn't be necessary to go that far. There is a theory about how the laws of this universe formed as it cooled down after T=0. The Standard Model describes in detail the emergence of gravity, the electromagnetic field, and the nuclear forces. Which leads me to wonder how people can argue so stubbornly, in the face of the most advanced physics we have, that the constants may not be variable. If they are not variable, then how did they get from indeterminate at T=0 to what they are now? That looks like quite a bit of variation to me.

But I forget. We didn't actually see that happen. Nevermind.

Isn't that the impetus for discovery? Forget what we can speculate about other universes, let's go out and try to find the buggers. It may never happen, which is why we can't say, definitively, that we are unique, sepcial, odd, mundane, or a dime for 10 billion. We just don't know, and need to fine out more. All I am advocating is to not call so-called fine tuning a problem when we have little to not evidence that it is fine tuned at all.

You guys worry so much about this fine tuning stuff. Don't sweat the small stuff. It isn't really fine tuning the way a multiverse would go about it. the multiverse version of fine tuning is more like an automatic improbability gun with the trigger stuck in the 'fire' position. The thing just keeps blasting away randomly until whatever can happen, does. Then it looks like fine tuning. But it's really just us being in one of the ludicrously unlikely places that the multiverse randomly blasted out of nonexistence, because that is where the ludicrously unlikely us would be.

No 'intelligent design' there. So relax. You don't have to worry about the multiverse condemning you to eternal torture.

It now seems obvious to me that the generic 'we' know more than you
think. I, for one, know better than to advocate going out and finding another universe, seeing as how it would take 'us' centuries to get to the nearest star system in this one.

You're right about one thing. We won't be laying hands on any other universes, that we might measure them for 'oddity'. You'll just have to trust me that they're all quite odd. Which is not at all like being 'unlikely'. In a multiverse, each individual pocket universe is quite odd in and of itself, but not at all unlikely. They just seem very unlikely to be the result of a one-off emergence event.

Theory is as far as we're going to get on that universe-finding trip. So that's as far as I would advocate trying to go.

How do you know they'd even listen or care? Or are you just assuming that they would?

I know because I altered your analogy to suit my purposes after you altered mine to suit yours. In my current version of the evolving analogy game, the aliens will listen. You alter my analogy, I alter yours.

 

[Kwalish Kid]

The above seems to be at the core of the different perspectives we have on this. I don't think we need to claim they are "odd" in order to want an explanation for them.

Again, this is where you are using your bias of me to assume my position rather than simply read my position.

I am in favour of investigating why the physical constants have the values they do, even if this investigation turns out to be fruitless.

I am opposed to saying that they have odd values without basis for this claim.

] In the absence of some universal law of everything from which we could derive all the fundamental constants, they remain unexplained -- is that "odd"?

That does not seem odd to me. Some things in the universe have to be unexplained, that see like one of the facts of explaining things; any explanation relies upon facts and principles that proceed from these facts.

I don't think fine-tuning is assumed as much as it is observed.

Can you think of a single observation that at the same time presents the mind with a probability distribution? Some inference must be made.

I agree that there is no reason to assume some other combination of the constants could not result in some other kind of universe that might include life and even intelligence. However, I'm at a loss to understand why you think fine-tuning requires some reason to believe the constants are not "those that we should see."

I have no basis on which to judge the nature of these constants. Do you want to propose the metaphysical presupposition that the constants that appear in laws of physics are always themselves fixed by other laws of physics? This seems to be a very dubious metaphysical principle to me.

On the other hand, it may be possible to actually discover that one or more physical constants actually does get its value from another physical theory. However, this physical theory should have its own evidence that would give the ability to judge it and through it the status of the law and constant this fundamental theory explains.

I also agree that " Fine-tuning arguments are bad when they are arguing from a weak anthropic argument to a grander claim of oddity." I don't believe fine-tuning arguments necessarily do that. The fact that a change in just one of many constants, say the fine-structure constant, would dramatically change the universe is enough to motivate us to ask, why is it what it is? Could it be different under some other initial conditions for the universe? Did it come about randomly? Is it inevitably the only value it could be? These are the questions that define fine-tuning. We do not need to regard α as "odd" to ask these questions.

I agree that we can ask these questions without regarding the values as odd. I wish that everyone would do this.

Getting back to the OP, I do see the megaverse conjecture as a possible answer to these questions.

Currently, is not really an answer at all. Without a supported physical theory, it is speculation about the nature of the universe on the basis of the need to explain something that may in the end not have or need and explanation. It is a better explanation than creation, but it is of the same speculative nature and explains physical phenomena perhaps only slightly better.

 

[Kwalish Kid]

I see. You have no data on my shooting ability, so you're settling for indirect inference.

However, he has a lot of knowledge about shooting and physics, this provides a lot of basis of a rough probability distribution or a family of reasonable distributions. In the case of why G has the value it does, it is not clear that there is anything analogous to shooting.

It could be the case that the value of G is simply a metaphysical requirement of gravitational coupling in any possible universe. It could be a fundamental part of what gravity is. In this case, the probability that G is the value it has is always 1 in every universe.

We might never discover this, but until we find some physical law governing the value of G, it remains something that could be the case and that makes a probabilistic understanding of G impossible.

But I was hoping it wouldn't be necessary to go that far. There is a theory about how the laws of this universe formed as it cooled down after T=0. The Standard Model describes in detail the emergence of gravity, the electromagnetic field, and the nuclear forces. Which leads me to wonder how people can argue so stubbornly, in the face of the most advanced physics we have, that the constants may not be variable. If they are not variable, then how did they get from indeterminate at T=0 to what they are now? That looks like quite a bit of variation to me.

It predicts when certain forces will dominate interactions in the early universe. Yet it does not assign values to the constants, these are fixed within the standard model in laboratory experiments. Nor does the standard model is not actually enough to explain the existence of all the particles that we have found with the properties that we have (e.g., neutrinos with mass). It is only in proposed extensions to the model that we have some fluidity in generating different constants.

I suspect that much of the talk of fine-tuning arose because string theory is far too loose in its ability to accommodate different physical constants.

You guys worry so much about this fine tuning stuff. Don't sweat the small stuff. It isn't really fine tuning the way a multiverse would go about it. the multiverse version of fine tuning is more like an automatic improbability gun with the trigger stuck in the 'fire' position. The thing just keeps blasting away randomly until whatever can happen, does. Then it looks like fine tuning. But it's really just us being in one of the ludicrously unlikely places that the multiverse randomly blasted out of nonexistence, because that is where the ludicrously unlikely us would be.

Yes, if we accept this version of the mulitverse theory, then the universe as we know it is unlikely compared to other universe. Yet we have no reason to accept this. Why should we engage in this strange speculation that supposedly resolves itself? If the answer is to feel giddy, then I suggest drugs instead.

It now seems obvious to me that the generic 'we' know more than you
think. I, for one, know better than to advocate going out and finding another universe, seeing as how it would take 'us' centuries to get to the nearest star system in this one.

So you had better be careful about not making claims that might require a trip to another universe in order to have any support.

You're right about one thing. We won't be laying hands on any other universes, that we might measure them for 'oddity'. You'll just have to trust me that they're all quite odd. Which is not at all like being 'unlikely'. In a multiverse, each individual pocket universe is quite odd in and of itself, but not at all unlikely. They just seem very unlikely to be the result of a one-off emergence event.

I do not agree that we should trust you or your speculative narrative about multiple universes.

Theory is as far as we're going to get on that universe-finding trip. So that's as far as I would advocate trying to go.

I agree that we can make some inferences about other universes on the basis of theory. I would like it to be well-supported theory.

 

[Toontown]

It could be the case that the value of G is simply a metaphysical requirement of gravitational coupling in any possible universe. It could be a fundamental part of what gravity is. In this case, the probability that G is the value it has is always 1 in every universe.

And why should we give any weight to this speculation of yours? You don't give any weight to ours.

We might never discover this, but until we find some physical law governing the value of G, it remains something that could be the case and that makes a probabilistic understanding of G impossible.

Well, no one has found any physical law governing the value of G. Or any indicaton that there is one. G simply seems to conspire with the other seemingly arbitrary constants in a way that happens to result in a universe we could be in.

But not to worry. It isn't really fine tuning. It's just that we will either observe what looks like fine tuning, or we will observe nothing at all.

It predicts when certain forces will dominate interactions in the early universe. Yet it does not assign values to the constants, these are fixed within the standard model in laboratory experiments. Nor does the standard model is not actually enough to explain the existence of all the particles that we have found with the properties that we have (e.g., neutrinos with mass). It is only in proposed extensions to the model that we have some fluidity in generating different constants.

Were the physical constants the same at T=0 as they were when they emerged to dominate interactions? If not, then they must have changed.

I suspect that much of the talk of fine-tuning arose because string theory is far too loose in its ability to accommodate different physical constants.

I don't think that's the reason.

Why shouldn't string theory be loose in it's ability to accomodate different physical constants? Got a probability distribution? Are you now committing the same thought crime you've accused us of?

And why should we entertain any of your speculations on this? You won't entertain any of ours, and prefer that we don't even mention them.

Yes, if we accept this version of the mulitverse theory, then the universe as we know it is unlikely compared to other universe. Yet we have no reason to accept this. Why should we engage in this strange speculation that supposedly resolves itself? If the answer is to feel giddy, then I suggest drugs instead.

The answer is not to feel giddy. And I've yet to see anyone in this thread ask you to entertain a speculation or to feel giddy. It's more like you were trying to squelch speculation in a free society, which is difficult. But you are persistent. What you cannot achieve by force you may well achieve by the application of sheer annoyance.

And you didn't even show us your thought cop badge.

So you had better be careful about not making claims that might require a trip to another universe in order to have any support.

I don't think I've made any such claims. I acknowledge that the support for the multiverse hypothesis is esoteric and hasn't been comprehensively covered in this thread. Most of what I've said was merely describing the general form of the hypothesis.

I do not agree that we should trust you or your speculative narrative about multiple universes.

I simply described what the multiverse hypothesis implies regarding the apparent fine tuning questions, i.e. that the apparent fine tuning is an illusion in a multiverse.

If you don't want me to tell you these things, then stop asking me questons about them. You never know, I might answer a question, and you'll be stuck with an answer you will feel compelled to squelch.

I agree that we can make some inferences about other universes on the basis of theory. I would like it to be well-supported theory.

Not to worry. If it isn't well supported, it won't ever be a theory.

But support can take many forms, most of which a strict empiricist will not accept.

 

[Perpetual Student]

Currently,(the megaverse) is not really an answer at all. Without a supported physical theory, it is speculation about the nature of the universe on the basis of the need to explain something that may in the end not have or need and explanation. It is a better explanation than creation, but it is of the same speculative nature and explains physical phenomena perhaps only slightly better.

I can't disagree with that. It is speculation. The issue comes down to your not seeing fine-tuning as a problem, whereas other people do.
Consider this: We can look at each fundamental constant separately and ask the question: Do we have any theory or conjecture to account for its value? Is there some probability distribution for this value? Does it stem for some other constant or some theory? So, we are forced to answer (for the most part) "no" and we have this same answer for a few dozen constants. OK so far, these constants are what they are -- we have no further information.
But then we observe that the consequence of all these values in combination result in the universe we are studying, with all its vast structure and complex chemistry, which includes life and us. Is it not compelling to speculate why that particular combination of all these constants is the one we see? We can calculate that if any one of these constants were tweaked by some amount, the universe we know would be vastly different and would necessarily exclude galaxies, stars, planets or life -- depending on which constant were tweaked and by how much. Is it not a compelling question to ask why this is so?
That, in essence, is the fine-tuning question -- and yes, all we can do is speculate.

 

[TubbaBlubba]

Indeed. And asking that question turned out to be rather useful, didn't it?

Did it? Wasn't the useful question "How the hell do we get Maxwell's equations to work while moving?" It happened to solve the magnetic field question, too. Similarly, I think the important question here is, "how do physical constants get their values?"

The fundamental physical constants indeed look fine-tuned. Why? Here are several possibilities:

(1) There is only one possible set of values for physical constants, and they are what they are. In this case, we should focus on understanding why only that set is possible. I find this highly implausible (for reasons I'd be happy to elaborate on).

(2) There are many possible values, and we are very finely adapted to the values they happen to take (the anthropic or "puddle" argument). This is more plausible, but not the whole story.

I can see a third possibility - the probability distribution of the constants look nothing like what we think it does.

I think - and yes, this is speculative, but based on mathematics and what we have learned about fundamental physics - that there are probably many, many possible values that vary as you move around in the universe, but not every conceivable set of values can occur, and some sets occur far more frequently than others. Some of the apparent fine tuning is anthropic (if the values weren't in certain ranges, no one would be here to ask about them), and some of it is due to interesting and as-yet poorly understood constraints on what is possible or common.

There is an active subfield in which people are exploring these possibilities. Speculative? You bet. Dead end? Maybe - time will tell. What's certain is that people are not going to stop discussing these questions. They're too interesting for that to happen.

Again, I don't mind the speculation and research about how fundamental physical constants arise, but starting with the question of constants being fine-tuned (rather than "how do physical constants arise?") appears to be putting the cart before the horse.

 

[Toontown]

Again, I don't mind the speculation and research about how fundamental physical constants arise, but starting with the question of constants being fine-tuned (rather than "how do physical constants arise?") appears to be putting the cart before the horse.

Include the apparent fine tuning as evidence. Why exclude from consideration what could be the critical clue?

 

[Hellbound]

I can see a third possibility - the probability distribution of the constants look nothing like what we think it does.

Actually, that's part of his number 2. It states nothing about probability values, only that there is a range of possible values.

Again, I don't mind the speculation and research about how fundamental physical constants arise, but starting with the question of constants being fine-tuned (rather than "how do physical constants arise?") appears to be putting the cart before the horse.

That's the mis-understanding. The "fine-tuning" problem is "How did the constants get their values". Why it's called the fine-tuning problem is because the constants can't vary by a large degree or strucutre and complexity become impossible (according to all the evidence and theory we can put together at this time). They "appear" to be fine-tuned. No one is making the assumption that fine-tuning exists, which seems to be your argument. In fact, speculations like the existence of a multiverse are ways to address this that don't call in any special fine-tuning. No one is assuming any particular probability distribution for the constants, so your option doesn't make sense in the terms of the question.

Now, certain speculations regardign the fine-tuning problem do make some assumptions, but these are speculations. They are, in logical terms, and If-then statement: If the constants have multiple possible values then it might be the case that there are numerous universes, either spacially or temporally. If the constants are proscribed into a narrow range then there might be an underlying theory that constrains them. That's it.

No one is stating anything about what the probability distributions must be. There are simply speculations about what the case might be if the probability was spread out (i.e.-the values essentially arbitrary). There is still work being done to try and find if there is some underlying theory that forces the values into a particular range. It's not as if everyone got together and said "they're random, let's stop looking", which seems to be what you're arguing against.

Basically, it comes down to sol's two options: Either there is a theory that sets these values, which we haven't discovered yet; or there is a range of possible values. I suppose you might class a very lop-sided probability distribution as a mix of the two (a theory contrains them into a small range of values).

 

[Fudbucker]

Actually, that's part of his number 2. It states nothing about probability values, only that there is a range of possible values.



That's the mis-understanding. The "fine-tuning" problem is "How did the constants get their values". Why it's called the fine-tuning problem is because the constants can't vary by a large degree or strucutre and complexity become impossible (according to all the evidence and theory we can put together at this time). They "appear" to be fine-tuned. No one is making the assumption that fine-tuning exists, which seems to be your argument. In fact, speculations like the existence of a multiverse are ways to address this that don't call in any special fine-tuning. No one is assuming any particular probability distribution for the constants, so your option doesn't make sense in the terms of the question.

Now, certain speculations regardign the fine-tuning problem do make some assumptions, but these are speculations. They are, in logical terms, and If-then statement: If the constants have multiple possible values then it might be the case that there are numerous universes, either spacially or temporally. If the constants are proscribed into a narrow range then there might be an underlying theory that constrains them. That's it.

No one is stating anything about what the probability distributions must be. There are simply speculations about what the case might be if the probability was spread out (i.e.-the values essentially arbitrary). There is still work being done to try and find if there is some underlying theory that forces the values into a particular range. It's not as if everyone got together and said "they're random, let's stop looking", which seems to be what you're arguing against.

Basically, it comes down to sol's two options: Either there is a theory that sets these values, which we haven't discovered yet; or there is a range of possible values. I suppose you might class a very lop-sided probability distribution as a mix of the two (a theory contrains them into a small range of values).

That's a good write up.

Let's say we discover a theory/principle that elegantly predicts all these crazy values we've been observing. Does that solve the problem, or just kick it up to a higher level? Because, if we do discover such a principle, the obvious question arises: why should the constants have those values that allow for life/complex structure to be possible, as opposed to any other values?

 

[Hellbound]

Let me try putting it a different way.

The "fine-tuning" problem relates to teh apparent fine-tuning of the physical constants.

The way to disprove that anything is fine-tuned, which is pretty much what the fine-tuning problem is, is to show:

1. There is an underlying theory that limits the values, or sets a particular probability distribution, that means the values aren't fine-tuned but have to be what they are (or close to it).

OR

2. The values are essentially random/arbitrary, but there are a multitude of universes, so we aren't fine-tuned, just one of many.

I often use too many words to express an idea, so maybe this is better

 

[Hellbound]

That's a good write up.

Let's say we discover a theory/principle that elegantly predicts all these crazy values we've been observing. Does that solve the problem, or just kick it up to a higher level? Because, if we do discover such a principle, the obvious question arises: why should the constants have those values that allow for life/complex structure to be possible, as opposed to any other values?

The why, in that sense, is a philosophical question.

But, for one example, the idea that black holes are actually "spawn points" of new universes. The values of physical constants that allow for conmplex structures and life turn out to be very similar to the values that allow for black holes. So, if black holes are spawnings of new universes, and the new universes "inherit" the constant values from the parent with some minor variations, then there is no "why" needed. The universes that make more black holes spawn more child universes, whose values are closer to the "right" ones. Eventually all the universes have values in the correct range, because the rest "died out", so to speak.

That's pure speculation, but provides an example of how there could be a bias to the numbers that doesn't involve any "why" in the sense you're asking about.

I suspect the final answer, whether multiple universes, underlying theory, or some combination fo the two, is going to have more suprises and bring up more questions.

But that's what makes science fun.

 

[sol invictus]

My inability to express myself mathematically may have garbled Stenger's argument.

Re-reading the chapters, I see that he lists all of the constants that have been claimed to be fine-tuned. Only three of these are being dismissed as "trivial and arbitrary". They are the speed of light, c, Planck's constant, h, and Newton's gravitational constant, G. He only consider those constants as "legitimate" objects of fine-tuning that are "dimensionless".

OK. In that case, I fully agree. It certainly is meaningless to talk about the values of dimensionful constants unless you've specified a set of units. But units are just a way of measuring one dimensionful quantity relative to another - in other words, taking ratios of two dimensionful quantities to produce a dimensionless quantity.

So it's only dimensionless quantities that have any physical meaning.

 

[Kwalish Kid]

I can't disagree with that. It is speculation. The issue comes down to your not seeing fine-tuning as a problem, whereas other people do.

Indeed, it seems that I refuse to adopt a fantasy probability distribution while others are all too keen to adopt one.

Consider this: We can look at each fundamental constant separately and ask the question: Do we have any theory or conjecture to account for its value? Is there some probability distribution for this value? Does it stem for some other constant or some theory? So, we are forced to answer (for the most part) "no" and we have this same answer for a few dozen constants. OK so far, these constants are what they are -- we have no further information.
But then we observe that the consequence of all these values in combination result in the universe we are studying, with all its vast structure and complex chemistry, which includes life and us. Is it not compelling to speculate why that particular combination of all these constants is the one we see? We can calculate that if any one of these constants were tweaked by some amount, the universe we know would be vastly different and would necessarily exclude galaxies, stars, planets or life -- depending on which constant were tweaked and by how much. Is it not a compelling question to ask why this is so?
That, in essence, is the fine-tuning question -- and yes, all we can do is speculate.

If I cannot provide a distribution to one, I certainly cannot provide one for their combination.

 

[Kwalish Kid]

Why shouldn't string theory be loose in it's ability to accomodate different physical constants? Got a probability distribution? Are you now committing the same thought crime you've accused us of?

Read some of the supposed fine-tuning scientific papers, you will find in many of them that they are addressing just the problem of trying to come up with a probability distribution for string theory.

Not to worry. If it isn't well supported, it won't ever be a theory.

That's a fine sophist defense of string theory.

 

[TubbaBlubba]

I suppose I am mostly arguing semantics, then.

 

[Perpetual Student]

...
...
If I cannot provide a distribution to one, I certainly cannot provide one for their combination.

I would like to try another analogy -- please indulge me.
Suppose you entered a town you had never visited before and found that everyone you saw had red hair. In every shop, in every home and everyone you saw in the street walking along had red hair. Now, might you not speculate how this can about? Was the town founded centuries ago by some redheads? Does everyone here dye their hair? Do only red-haired people move to this town? Is there something in the water causing then to become redheads?
Well, you can freely speculate why everyone you see in this town has red hair without knowing anything about the probability distribution of red hair. Of course, knowing the probability distribution will tell you what the chances are of this being a result of chance, but that's not necessary to speculate.
I know this analogy is not exact since we know what possible colors of hair humans have but we do not know anything about what alternative values (if any)the constants might have. My point here is to provide some framework as to why it is reasonable to speculate about fine-tuning with no knowledge of a probability distribution.
Now you can tell me why this is all wrong!

 

[Kwalish Kid]

I would like to try another analogy -- please indulge me.
Suppose you entered a town you had never visited before and found that everyone you saw had red hair. In every shop, in every home and everyone you saw in the street walking along had red hair. Now, might you not speculate how this can about? Was the town founded centuries ago by some redheads? Does everyone here dye their hair? Do only red-haired people move to this town? Is there something in the water causing then to become redheads?
Well, you can freely speculate why everyone you see in this town has red hair without knowing anything about the probability distribution of red hair. Of course, knowing the probability distribution will tell you what the chances are of this being a result of chance, but that's not necessary to speculate.
I know this analogy is not exact since we know what possible colors of hair humans have but we do not know anything about what alternative values (if any)the constants might have. My point here is to provide some framework as to why it is reasonable to speculate about fine-tuning with no knowledge of a probability distribution.
Now you can tell me why this is all wrong!

The speculation here seems like a different sort, but let's accept it for now. I encourage people to speculate on why the people inthe town have red hair, but I would not encourage them to use that speculation to bet that all the people in the next town over have blonde hair.

 

[Fudbucker]

I would like to try another analogy -- please indulge me.
Suppose you entered a town you had never visited before and found that everyone you saw had red hair. In every shop, in every home and everyone you saw in the street walking along had red hair. Now, might you not speculate how this can about? Was the town founded centuries ago by some redheads? Does everyone here dye their hair? Do only red-haired people move to this town? Is there something in the water causing then to become redheads?
Well, you can freely speculate why everyone you see in this town has red hair without knowing anything about the probability distribution of red hair. Of course, knowing the probability distribution will tell you what the chances are of this being a result of chance, but that's not necessary to speculate.
I know this analogy is not exact since we know what possible colors of hair humans have but we do not know anything about what alternative values (if any)the constants might have. My point here is to provide some framework as to why it is reasonable to speculate about fine-tuning with no knowledge of a probability distribution.
Now you can tell me why this is all wrong!

A preponderance of red-heads would only be a problem if you had prior knowledge of the distribution of red-headed people.

Suppose we visit an alien town and notice everyone is four-legged. I don't see a problem unless we had some prior idea of whether four legs was the norm for that species. We would certainly wonder why everyone has four-legs though, but it wouldn't be a "problem" without some prior information.

I deliberately didn't read Kwalish's response. I'm curious if he will bring up a similar point. LOL, I read it and can't tell what he's saying.

Perpetual, let's take your analogy and suppose we had good reason to predict the four-legged alien townsfolk should actually have 20 legs (or no legs). Does the huge difference between what we've observed and what we predicted constitute a problem? I think so, because anytime you get a very surprising result (i.e., a result totally different than what you expected), you need an explanation for why the result was surprising.