Pevaquark Doesn't Like Fine Tuning Apologetics and Neither Should You

[pevaquark (Matthew Pevarnik)]

@EricH

I have been trying to get my head around why so many cosmologists conclude there is fine-tuning, but you two think we don’t know enough to describe the sample space of possible universes. Here’s my thoughts so far.

We don’t!

@EricH

Barnes’ definition is based on “possible universes” allowed by theoretical physics.

What he means is that if we arbitrarily vary the constants of physics, we can use theoretical physics to say which of those universes allow for life/stars like ours. The boundaries of such parameter space scans are made up, but the limits that allow for physics like our are not. But this in no way shape or form are the actual possible universes because not even the best theoretical physics can say this- nobody knows what “possible universes” there are. There is a subtle but extremely important difference between the two.

@EricH

If the possible ranges may be narrower than allowed by current theoretical physics, as Matthew suggests

The ranges are not ranged that are allowed by current theoretical physics because nobody knows what possible ranges are! All that we know is what ranges within the parameter space scans allow for physics that is important for life/stars. I’m not suggesting that the ranges within the parameter space scans should be “narrower” as this would indicate even more extreme “fine-tuning” but what I am suggesting is the boundaries of such scans are entirely unknown. That is something that all of these Cosmologists readily admit.

@EricH

”Our claim is that fine-tuning claims can be understood in the context of objective Bayesianism, and that the difficulties faced in calculating the relevant probabilities are of the same kind as those faced in analysing any physical theory.”

What does this mean to you? The section is a good section regarding how do you try to find out if any physical theory is an accurate description of reality. Re-reading it is highly recommended. I’d probably have to read through it ten times to be able to speak with some understanding on their arguments. Of note is of course their summary on p.288:

We haven’t made a watertight argument here, much less performed a calculation.

They say some more nice things but notice: they can’t give you any probability because even a Bayesian analysis requires information that they don’t and can’t have. And they also can’t calculate the probability via other means because nobody knows what possible values the constants can take!

@EricH

So I think we have no choice but to say that the current physics of fine tuning is not able to be explained either by chance or necessity

Well sure, because we don’t know how universes and constants of physics are made/determined. But by all means, please don’t turn that around to some kind of argument for God as this would be a god of the gaps type of argument.

@EricH

I thunk we should work with the concept of “possible” and make sure that any fine-tuning theistic argument reflects that uncertainty.

I don’t think there is any fine-tuning theistic argument but I would appreciate if those that make such accurately reflect what cosmologists are saying.

[MarkD (A Whateverist, not a Christian)]

@pevaquark

The ranges are not ranges that are allowed by current theoretical physics because nobody knows what possible ranges are!

@EricH, what exactly do you have in mind when you refer to “what current theoretical physics allows”? You’ve read some research in which theoretical physicists have tinkered with the constants which actually do describe the way the universe works in order to predict the repercussions for the resulting hypothetical universes that result from arbitrary changes to those constants. Don’t you agree that that is not the same thing as an endorsement that such hypothetical universes could actually exist. And Pevaquark confirms that in fact theoretical physicists do not claim these hypothetical universes are possible because no one knows that.

Do you think it is possible that you have inadvertently quote mined what you’ve read out of your eagerness to find something that confirms your religious beliefs or which might even help you spread the word? I don’t mean that to be insulting. This can happen to anyone. But looking for quotes which can be interpreted in a way that confirms what you hope to find is bad science.

[Totti (Luca)]

Hi guys!
I’m following this conversation, silently lurking in the background.
And i’m just trying to get what you both are saying.

Eric is saying that most scientists accept this fine tuning.
And that fine tuning is known in our known universe.
And he is making a probability claim?
But then you Matthew, are saying that we can only know the fine tuning, or constants. Of the universe we currently know? So we can’t make a probability argument because we don’t know what the rest could be?

Sorry if i’m entirely off the mark. But this is very interesting.

[ManiacalVesalius]

Now I hope that you could see why such a statement is nonsense, because nobody knows what’s range of values these constants can take and with the probabilities of getting each of those values even is. So you can make the bounds as big or as small as you want, nobody knows and nobody can tell you’re wrong, but to suggest that it falls within some kind of narrow range without even knowing what the range could be is quite confusing to me and I would dare say misleading.

I think this is your principle point, that we don’t know what variability these constants can take in the first place, so we really can’t conclude any fine-tuning. Some time ago I thought (and I just remembered now) something I would, say, be able to use to get around this point. Inevitably, if some of the constants were a little higher or a little lower (disregarding for now whether or not they can be), life clearly couldn’t exist. I think one of the constants, such as the expansion rate of the universe if I’m not mistaken, makes the difference between the elements we see or just hydrogen. So, can the constants be different? If they could be different, then there’s little debate. But what if they couldn’t be different? What if, indeed, the constants we see are the only possibility? I would suggest here that the very fact that the constants we see are in the narrow range of allowing life are the only possible constants there could be reinforces fine tuning. To me, the only way I see fine tuning being invalidated is if there was simply a much wider range for life being able to exist, so that we don’t see ourselves sitting on a big fat coincidence. Until then, whether or not the constants can be different or not does little to reinforce the point that the constants of the universe exist within the necessary narrow range for life to be possible.

[Bill_II]

@ManiacalVesalius

I would suggest here that the very fact that the constants we see are in the narrow range of allowing life are the only possible constants there could be reinforces fine tuning.

That should be “narrow range of allowing life as we know it” Life may exist in a different form. Not carbon based and using water as a universal solvent. We can speculate but there is no way to rule out life in other forms.

[heddle (David Heddle)]

@Bill_II

That should be “narrow range of allowing life as we know it ” Life may exist in a different form.

I disagree. The universe appears to be fine tuned for nucleosythesis. There easily could have been no stars, and even with stars the nucleosythesis in the stellar furnaces appears to be a house of cards. With no nucleosythesis there would be no heavy elements, only hydrogen and helium. And without heavy elements there is no life of any kind.

The universe is fine-tuned, if you will, to make rocks and, as a happy byproduct, the ingredients for any kind of life. And it’s fine-tuned regardless of the probability of the constants–which really shouldn’t enter into the discussion, though it always becomes the center of the discussion.

[MarkD (A Whateverist, not a Christian)]

@ManiacalVesalius

I would suggest here that the very fact that the constants we see are in the narrow range of allowing life are the only possible constants there could be reinforces fine tuning. To me, the only way I see fine tuning being invalidated is if there was simply a much wider range for life being able to exist, so that we don’t see ourselves sitting on a big fat coincidence.

This really does suggest that chestnut about the puddle marveling at how well its hole fits it. We live and, lo and behold, we live in a life permitting universe.

It is still good fortune for us that the conditions do permit for our existence, but why I wonder should we use the expression “fine tuned” to express the aptness of the fit? Wouldn’t fortuitous serve equally well? Otherwise should we not also describe a pleasant day as fine tuned, or arriving at the check stand at a moment when the line is short? Does “fine tuned” carry some other significance than simply expressing our gratitude at finding the life supporting capacity of the universe to our liking?

[MarkD (A Whateverist, not a Christian)]

@heddle

The universe is fine-tuned, if you will, to make rocks and, as a happy byproduct, the ingredients for any kind of life. And it’s fine-tuned regardless of the probability of the constants

Yes, it is a fine thing. But why that expression? When I hear “fine tuned” I think of musical instruments and car engines. If an instrument plays in key or a car’s engine idles nicely then someone is to be congratulated on their work. Nicely tuned.

Anyone who starts off believing in a creator will have no trouble crediting the smooth operation of the universe to Him. Nice tuning, God. But attempts by apologists to convince a non-believer the Creator exists based on the smooth running of the universe will never work, and will always strike us as circular.

[jpm (Phil McCurdy)]

Tuning implies that something can be adjusted or changed. Is there really any evidence that the universe could actually be anything other than what it is?

[heddle (David Heddle)]

Well I, for one, never try to convince an unbeliever that God exists. I give the gospel. End of story. (Unless they want to talk about it.) The fine-tuning is a) an interesting scientific puzzle (demanding an explanation) to me as a physicist, independent of my faith, and b) an apologetic – not for unbelievers, but for believers.

I don’t get why anyone would be upset by the term “fine-tuning”. I don’t know who coined it, but I wouldn’t be surprised if it was a non-believer. It’s just descriptive language. In peer-reviewed papers you can easily find statements such as “the electron knows which path to take.” We use descriptive and anthropomorphic language all the time in science. It is not meant to be taken literally.

EDIT: Typo

[MarkD (A Whateverist, not a Christian)]

Well this is what grates for me about the fine tuning argument. We don’t know if it could be adjusted, so conclusions relying on such premises are pointless.

[EricH (Eric Hatfield)]

@pevaquark

We don’t!

Hi Matthew,

I’m sorry if I haven’t understood you correctly. I honestly have been trying to. But this isn’t the first time I have tried to summarise my understanding of your position, only to find I haven’t got it right. You also seem to think that I may have misunderstood the expert cosmologists as well.

I have delayed replying for a day while I have considered this. I am usually able to read and understand what others say, and to summarise it in simple terms. For example, in my work as a hydrologist and environmental manager, I managed a group of applied scientists (ecologists, biologists, water chemists, geomorphologists, etc) and I often had to take their detailed expert advice and turn it into a brief submission to the organisation I worked for.

So I am wondering whether I do get the general idea of what you are saying, but don’t express it with the rigour that you prefer. Maybe so, maybe not.

Anyway, I think it is better that I give up the attempt to understand and respond to your ideas in this discussion, to avoid further misunderstanding. I’m sorry to have to do this, for I think it could have been profitable.

Thanks for your time, your ideas, and your courtesy.

[EricH (Eric Hatfield)]

@MarkD

Do you think it is possible that you have inadvertently quote mined what you’ve read out of your eagerness to find something that confirms your religious beliefs or which might even help you spread the word?

Yes, I’m sure that’s possible. I try to be even-handed about assessing these things, but obviously I have my interests and hence possible biases, just as everyone else has. I try to guard against this by always checking both sides of the question. So I have read Luke Barnes (who seems to have moved from a more agnostic view to a theistic view in the past couple of years, though I may not have judged that correctly) and Aron Wall (who is a christian), but I have also read Paul Davies, Martin Rees, Leonard Susskind and Roger Penrose who are all agnostic about God and definitely not theists. And as well as reading all those cosmologists who think the universe is “fine-tuned”, I have read and listened to Sean Carroll who does not think that. So I don’t think it is just my biases.

what exactly do you have in mind when you refer to “what current theoretical physics allows”?

To my mind, a possibility is a possibility. In this case, we have a double sense of “possibility”.

(1) Unless the multiverse is true, these alternative universes don’t actually exist. They are hypothetical, or counterfactuals.

(2) It may be true that they were equally possible as the universe we experience, we have no reason from theoretical physics to say that it isn’t true, but we cannot say for sure that it is true.

They are possibilities.

You’ve read some research in which theoretical physicists have tinkered with the constants which actually do describe the way the universe works in order to predict the repercussions for the resulting hypothetical universes that result from arbitrary changes to those constants. Don’t you agree that that is not the same thing as an endorsement that such hypothetical universes could actually exist.

I don’t know exactly what it means to say “such hypothetical universes could actually exist”. The statement could be interpreted in different ways. It is conceivable that they do exist as part of a conceivable multiverse. It is conceivable that they were equally likely as our universe to have appeared instead of ours. So they are conceptual possibilities. And there is no physical reason to say they couldn’t exist as part of a multiverse or have appeared instead of our own, though no physical certainty, so they are physical possibilities.

And Pevaquark confirms that in fact theoretical physicists do not claim these hypothetical universes are possible because no one knows that.

I don’t know if Matthew actually says that, and again I think use of the word “possible” can be ambiguous for the reasons I have given. But I don’t believe he is in a position to “confirm” this matter. He undoubtedly knows more physics than I do, but unless he tells me otherwise, he doesn’t know as much cosmology as the 20+ experts Barnes quotes (not to mention Barnes himself), and I still say those experts confirm the scientific fact of fine-tuning. If you still question this, I suggest you read Barnes’ paper, or ask me to give you quotes from some of them.

But in the end, I don’t want this to become an argument between him and me about what other people think and say. You’ll have to decide for yourself, do some reading and see what you can understand and conclude.

Thanks.

[MarkD (A Whateverist, not a Christian)]

@EricH

I try to be even-handed about assessing these things, but obviously I have my interests and hence possible biases, just as everyone else has.

My feeling exactly.

@EricH

I don’t know exactly what it means to say “such hypothetical universes could actually exist” . The statement could be interpreted in different ways. It is conceivable that they do exist as part of a conceivable multiverse.

No, I’m not referring to other universes if they do exist. I can’t imagine how we’d ever access information for them anyway. The universe of which we know anything at all just is the way it is. No one can currently say it could have been otherwise, though perhaps it could. But the fact that it is this way instead probably is determined by more than a roll of the dice. Just because we can dream it up doesn’t mean it could be any other way.

But I’ll respect your choice to leave it here. I certainly don’t have anything new to add. But I assume your motivation in all this is the part we never talked about, the roll it plays in the apologetics argument for God based on fine tuning. Peace out.

[pevaquark (Matthew Pevarnik)]

Hi Eric,

Thank you for your time. Just to clarify that “we don’t know enough to describe the sample space of possible universes” because we don’t know what universes are even possible in the first place. I am probably being over picky on the specific wording since it is easy for someone to think that any theoretical physics actually knows what the bounds and ranges are for various constants despite their frequent modeling of various ranges. The words of Barnes that I shared on my 2nd video on the odds of making a star summarize my position that we can model ranges and combinations of fundamental constants that are life-permitting but we cannot go anything beyond this at present.

[EricH (Eric Hatfield)]

@MarkD

But I assume your motivation in all this is the part we never talked about, the roll it plays in the apologetics argument for God based on fine tuning.

Not entirely. I have always been interested in astronomy. In Sydney there used to be a technological museum which had its own little planetarium, and every hour about 30 people could sit inside and be taken through a program of showing the stars and planets in Sydney’s night sky at that time of year. I used to love it. One day as a young teenager I spent almost the entire day in that museum, going to every session of the planetarium, I think 5 or 6 in all.

So I am very interested in astronomy and cosmology, and I read about more than just fine-tuning. But of course I am interested in the theistic arguments, both the cosmological and the design arguments, that are based upon the science. But as I have said, I try to get the correct and best science. For example, when I was young, evolution wasn’t as well established in the public mind, and I never studied biology at school or uni, but when I finally started to consider evolution seriously (partly through this website, actually), I was quite willing to accept that the science totally showed 6-day creation was not a fact. Likewise i read a bit on neuroscience, and I accept the science of the brain, consciousness, how religious belief forms, etc, that the neuroscientists have found, though of course I don’t necessarily accept the reductionism and the amateur philosophy of some neuroscientists.

So I’m only interested in the genuine consensus of cosmologists on fine-tuning. Peace to you too.

[GJDS]

Correct. A constant is not a variable, so it does not make sense to argue on how constants may be varied or changed. The implications from this have created debate, as something that is set (constant, cannot be varied) implies purpose and caused …. it certainly negates outlooks that believe happenstance can lead to such an array of constants.

[pevaquark (Matthew Pevarnik)]

@GJDS

A constant is not a variable, so it does not make sense to argue on how constants may be varied or changed.

We don’t actually know or assume that just because someone called them a ‘constant’ in the English language, that they actually are indeed constant. Though most measurements set upper bounds for how much they could possibly vary:

Time-variation of fundamental constants

Like the proton to electron mass ratio is pretty much zero:
http://science.sciencemag.org/content/339/6115/46

This is a cool paper that actually makes a theoretical prediction of how much we should measure the fine structure constant varying (note: not an oxymoron ) due to the expansion of the universe that is within the ballpark of what we measure:

Variation of the fine structure constant caused by expansion of the Universe

Here were some other neat measurements that do measure a change in the fine structure constant over time (albeit very small):
http://astronomy.swin.edu.au/~mmurphy/research/are-natures-laws-really-universal/

[MarkD (A Whateverist, not a Christian)]

I’m learning a heck of a lot on this website. Thank you!

[GJDS]

@pevaquark

We don’t actually know or assume that just because someone called them a ‘constant’ in the English language, that they actually are indeed constant. Though most measurements set upper bounds for how much they could possibly vary:

As always, discussions with you are never boring Matthew and I thank you for the links - I get the abstract but I cannot find the time to examine the papers.

Having said that, I think we will have to age many thousands of years before I can witness QM molecular modeling vary the charge of the electron, or known properties of protons (relativistic terms are included).

Speculation is interesting, but your comments simply show that we can improve our measurements. The values of the constants may become more accurate, but that is about it.

It is not about the English language or what terms we use, it is about the practice and understanding of the branches of science. No matter how some may speculate on possibilities (and I note you do not like probability arguments on this, and btw I agree), we are bound to treat given terms as constants in (our/my) discipline, with the best values available. A simple example is pi - the value can go on and on, but I cannot fathom it becoming a variable any time soon.