Fine-Tuning Problem in Cosmology

[Toontown]

At this point I say "what apparent fine tuning" and you tell me what plays second base.

No, I say "the apparent fine tuning you are in denial about".

The universe looks fine tuned, the universe looks designed so are you on the ID bandwagon?

No, as I just explained in my last post. No, as desperately as you want me to be on the ID bandwagon. No. Already explained repeatedly why not and how not. Read, not for buzzwords to isolate and highlight, but for comprehension. Read and acknowledge, or look increasingly like a troll. Those are your choices.

The inflationary multiverse with variable constants is not heresy. The hypothesis is quite reasonable, simply suggesting the universe may be bigger and more diverse than the part we can see now, as has repeatedly been the case at every stage of the learning process about the universe.

When it was suggested that Earth was but a cog in a solar system, there was outrage and calls to burn the heretic at the stake.

When the existence of the solar system was finally grudgingly accepted (but not before burning Giordano Bruno at the stake), many sullenly refused to consider or discuss the possible existence of other solar systems.

Then the existence of the galaxy was discovered, and once again, many sullenly refused to consider or discuss the possibility of other galaxies.

Then Edwin Hubble laughed derisively and pointed a big telescope at a tiny dark spot in the sky, and kept it pointed precisely at the spot until hundreds of galaxies appeared on a photographic plate, revealing what was hidden in the tiny speck of darkness.

At this point, the discerning reader should have no difficulty working out which bandwagon you're on. You're on the one that's been a dead bust all along.

 

[Fudbucker]

What happened to this forum? There used to be physicists who posted here, and people whom you didn't have to explain elementary concepts to. Did they leave?

 

[ehcks]

What happened to this forum? There used to be physicists who posted here, and people whom you didn't have to explain elementary concepts to. Did they leave?

Well, there are also crazy people who post nonsense then get defensive and upset when you tell them that.

 

[BenBurch]

This is a diverse group. Now back on topic; How can you differentiate between the two positions from within the system?

I think living in a universe that was intentionally tuned to allow 0.00000001% of the universe to be hospitable to life would be indistinguishable from living in one of an infinite number of universes where 0.00000001% of the universe was hospitable to life. In what way would you differentiate?

 

[Dancing David]

For some of us "Why?" is an irresistible question.
Why does the electron have the mass, charge, spin, magnetic moment, etc. that it has? Why are all electrons identical? Could it have been otherwise? Broaden that question to all the other fundamental values we see in nature and one has a multiplicity of questions. All of these values (including the fine structure constant, the gravitational constant, cosmological constant, etc.) are tied to the nature of the universe, including its chemistry, structure and dynamics.
Asking if it could have been otherwise seems to me to be a compelling question -- a question that I would like to see "resolved" -- to use your word. But -- perhaps not for everyone. That's OK.

Some of the constants are [products of other events and yes asking why is a great question.

It has yet to be demonstrated that the 'fine tuning' exists or is even a possibility. Questions are important, yet it seems the question about fine tuning presupposes that there is fine tuning. That is why I stated that both my preference and the idea that constants are variable are equally speculative. And at this point moot.

So while I consider the mass of the electron, quarks and partial charges to be very interesting questions, I find the idea of fine tuning to be philosophical. Now if some future ToE, future observations, brane theory, string theory or the LHC shows that the constants could have had widely disparate values, then I would say it is a poser.

Currently I think the ideas of super symmetry (and its current problems) are more interesting because they can be tested.

 

[Dancing David]

It's survival proves that the Internet is finely tuned for this forum.

Look how many variables had to be just right for it to happen.

There had to be a member who was willing to host it and had the ability to do so:

odds 23,000 to one

The board had to agree to work with him:

odds 10,000 to one

We can see that it's so improbable that it must be fine tuning that explains it.

 

[Dancing David]

What happened to this forum? There used to be physicists who posted here, and people whom you didn't have to explain elementary concepts to. Did they leave?

Um, you can PM Ziggurat, Cuddles or Sol Invinctus and ask them to participate (there are others like Epekeke as well). However having seen their effect on people in Many Worlds Interpretation threads and others the effect can be interesting at least.

As a courtesy to other POVs I have chosen not to do so.

 

[Dancing David]

Just as this pocket universe is completely explained by the fact that the inflationary multiverse spawns a multiplicity of them, with a multiplicity of variable parameters.

Hi again, I really think you could you terms like 'possibly, theoretically and might', having heard and read many people like Guth, Greene and others talk about these vary topics, that is the way they a dress it.

Inflationary theory supports the possibility of recursive space time foam and the generation of universes in an unknown matrix.

But the term 'pocket' universe is a supposition, there is a possibility of infinite and closed universes, I never quite understand the math when this has been explained on the forum by people who do understand the theory. I think it was Punssssh thread on the form of the formless.

 

[Toontown]

This is a diverse group. Now back on topic; How can you differentiate between the two positions from within the system?

I think living in a universe that was intentionally tuned to allow 0.00000001% of the universe to be hospitable to life would be indistinguishable from living in one of an infinite number of universes where 0.00000001% of the universe was hospitable to life. In what way would you differentiate?

The answer to your question is far too complex to bother trying to adequately address here.

However, it is not as if scientists are giving the inflation hypothesis short shrift. Many scientists find the hypothesis sufficiently compelling to form associations aimed at running large scale computer simulations to get more firm predictions and then testing the predictions with hard observations designed by other groups. This work is well underway on several fronts. If we are in an inflationary bubble, it will look, from the inside, exactly like an inflationary bubble. If we are in something other than an inflationary bubble, it is extremely unlikely that it will look exactly like an inflationary bubble.

There is already observational evidence for inflation. The inflation hypothesis predated and predicted some hard observations which came later, forcing cosmologists to include an epoch of inflation in the standard big bang model.

The designed universe is merely a flight of fancy which can make no predictions. The one-off popgun that is the way it is because it can't be any other way for some undiscovered reason (which you didn't mention), is on similar footing with the designed universe. Neither of these flights of fancy have any possibility of making any firm or meaningful prediction.

Read the article and follow the imbedded link about how the inflationary multiverse "would explain some otherwise puzzling astrophysical observations". Be forwarned that you will be entering a labrynth. But you did ask for it. And you'll be getting more of it as the investigation continues. This isn't going to get any simpler.

https://www.perimeterinstitute.ca/node/94107

 

[Toontown]

It has yet to be demonstrated that the 'fine tuning' exists or is even a possibility. Questions are important, yet it seems the question about fine tuning presupposes that there is fine tuning.

Once again: when cosmologists speak metaphorically of "the fine tuning problem", they are not suggesting that fine tuning, in the ID sense, exists. OTC, they are saying that the appearance of fine tuning exists, and needs a better explanation than "Goddunnit", or "it's moot". It needs a naturalistic explanation. That's all they're saying. To cosmologists, "the fine tuning problem" is simply a metaphor for an observation that requires a lot of words to fully describe.

I don't understand why it is taking so long for this to get through to you. Do you have a problem with metaphors?

 

[Fudbucker]

Should we let Sol have the last word?

The “finely tuned argument” that the religious folk like to use is nothing more than a logical miscomprehension.

One finds organs (like eyes) that are exquisitely adapted to their purpose. They are incredibly "fine-tuned", and we understand why - because of natural selection.

So why are people here so resistant to the idea that precisely the same logic - noticing fine-tunings and looking for a natural explanation - could be useful in physics as well?

For any argument of fine-tuning to make sense you have to assume that the constants could have been other than what they are, but at the same time that there are no other Universes. Because, if there are multiple universes its hardly surprising that we find ourselves in one in which human life is possible.

I'm not sure the rest of us know what you mean by "argument of fine-tuning". In models in which other regions of the universe with different values of the constants exist, one can observe that ours is fine-tuned for our form of life, and then explain that tuning with the anthropic principle. When this is discussed in the physics literature that's generally the idea.

Because we don't understand how they're interconnected, if at all. It could be analogous to, say, "why is the magnetic field active only when moving?" pre-SR.

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

The problem with this framing is that it is misleading and provides apparent support for those who present design arguments for the existence of the universe. A popular argument for creationists is that the universe as it exists is miraculous, that the universe is in such an unlikely state as to require a creator.

When it was first proposed, people objected to the big bang on similar grounds.

Science proceeds by asking questions about phenomena that look intriguing to scientists. If some of those investigations or their (possibly tentative) conclusions disturb your personal worldview, tough luck. Science and scientists couldn't care less (or at least they shouldn't, unless we are discussing things that might actually pose a real risk).


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 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.

 

[Kevin_Lowe]

The answer to your question is far too complex to bother trying to adequately address here.

That pretty much sums up the "fine tuning" arguments in this thread.

 

[Toontown]

The answer to your question is far too complex to bother trying to adequately address here.

However...

https://www.perimeterinstitute.ca/node/94107

That pretty much sums up the "fine tuning" arguments in this thread.

There are no "fine tuning" arguments in this thread.

When you have figured out why the above is true, you will have reached the metaphorical bottom of the staircase.

If you reach the metaphorical bottom of the staircase, you can then follow my link above and the imbedded link within it, if you want to know more.

 

[tsig]

We've had a bit of a heated discussion in the R&P section about whether fine-tuning is a problem in cosmology. So I thought I would take a poll.

This is the best summary of the fine-tuning problem that I could find:

"Embedded within the laws of physics are roughly 30 numbers—including the masses of the elementary particles and the strengths of the fundamental forces—that must be specified to describe the universe as we know it. Why do these numbers take the values that they do? We have not been able to derive them from any other laws of physics. Yet, it’s plausible that changing just a few of these parameters would have resulted in a starkly different universe: one without stars or galaxies and even without a diversity of stable atoms to combine into the fantastically complex molecules that compose our bodies and our world. Put another way, if these fundamental parameters had been different from the time of the Big Bang onward, our universe would be a far less complex universe. This is called the “fine tuning observation.” The fine-tuning problem is to find out why this is."
http://www.pbs.org/wgbh/nova/blogs/physics/2012/12/scientific-approaches-to-the-fine-tuning-problem/

Is Lee Smolin right? Is the observation of "fine tuning" a problem that needs to be solved?

I think it is, there are plenty of experts who agree, and I think it's a big driver in the popularity of inflation theory (a multiverse solves the fine-tuning problem quite elegantly), but I submit the question to you guys:

Fine-tuning, a problem or not?

The Fine-Tuning Problem is like taking the Texas Sharpshooter Fallacy, forgetting that you fired the arrow, then proclaiming that some special force drew the bulls eye there.

We are where we are because we are here. If we were somewhere else, we'd be talking about how we are there and why were not in yet another place. If we weren't anywhere, we wouldn't be talking.

Where is the proof that different values would necessarily result in far less complexity?

Our current universe is 99.9999999999999999999999999% empty space. You call that complex? Our bodies may be composed of 'fantastically' complex molecules, but we are an insignificant part of the Universe - a tiny speck of crud that wouldn't be missed if we didn't exist. How can we insist that a different universe wouldn't be complex enough to support life, when our own universe is so devoid of it?

And what makes us think that these 'fundamental' parameters have independent values that could be freely chosen? I bet they are actually the result of even more fundamental parameters having relationships that we just haven't discovered yet.

I voted yes. There are a number of possible explanations for why our universe seems “fine-tuned”. The parameters in question might not actually be independent, many universes with a variety of parameters might exist, or there might be no specific reason at all (i.e. coincidence). Trying to find out which of these (or other) explanations is correct seems like a very productive line of inquiry to me.

For the people who voted no, do you think that we no longer should look into this “problem”? Change some of our priorities for research? What would the practical consequences be for science if we would consider “fine-tuning” less of a problem?

No. As others have said, it's a fallacy.

this is silly for a number of reasons:

-say that a value needs to be fine tuned between .01 and .02 , how many possible values can exist between those two numbers?

This is old but a very good read and discusses the actual foolishness of the FTA:

Victor J. Stenger

http://www.colorado.edu/philosophy/vstenger/Cosmo/FineTune.pdf

There are no "fine tuning" arguments in this thread. When you have figured out why the above is true, you will have reached the metaphorical bottom of the staircase.

If you reach the metaphorical bottom of the staircase, you can then follow my link above and the imbedded link within it, if you want to know more.

I only went down to post 24.

Apparently when you say fine tuning you mean just what you want to mean and no more.

 

[Kevin_Lowe]

There are no "fine tuning" arguments in this thread.

When you have figured out why the above is true, you will have reached the metaphorical bottom of the staircase.

If you reach the metaphorical bottom of the staircase, you can then follow my link above and the imbedded link within it, if you want to know more.

Oh, how clever. You decided that my words meant something other than their obvious, intended meaning and replied to that instead.

There is no great virtue in speculating without evidence. Currently there are no observations that would help us determine whether we are in a universe that supports life when this is improbable for deep reasons we currently do not understand, or in a universe that supports life when this is unremarkable for deep reasons we currently do not understand. The fact that we exist and think about it is not evidence either way because it fits equally with either hypothesis.

 

[Toontown]

I only went down to post 24.

Apparently when you say fine tuning you mean just what you want to mean and no more.

Doesn't everyone? Seems like a waste of time to try to mean what you don't want to mean. Do you do that often?

As far as I'm concerned, if someone wants to mean something else, it's up to them to mean that. I'm not going to mean it for them.

I know what scientists mean when they say "fine tuning". I know what theists mean when they say "fine tuning". It ain't the same. And neither camp is trying to mean what the other camp means. The theists mean it literally. The scientists mean it metaphorically.

The scientists who mean it metaphorically do not make arguments for fine tuning. Theists make arguments for fine tuning, but have not done so in this thread. The scientists simply see the appearance of fine tuning as a likely clue to the nature of the universe, which makes some of them want to look for a naturalistic explanation, because that's what scientists do. Not unlike what Newton did when he noticed that things always fall toward the ground. He saw that as a clue, while it never even occurred to the incurious to wonder why things fall toward the ground instead of up or sideways. And if Newton had bothered to inform the incurious of his suspicions, the incurious would have yawned and told him it was moot.

BTW, none of the examples you thought you found contained any arguments either for or against fine tuning. There were some appeals to incuriosity and ignorance, but there were no theistic arguments for it, and the quotes from scientists were simply the metaphorical use of the term.

 

[Toontown]

Oh, how clever. You decided that my words meant something other than their obvious, intended meaning and replied to that instead.

There is no great virtue in speculating without evidence. Currently there are no observations that would help us determine whether we are in a universe that supports life when this is improbable for deep reasons we currently do not understand, or in a universe that supports life when this is unremarkable for deep reasons we currently do not understand. The fact that we exist and think about it is not evidence either way because it fits equally with either hypothesis.

Then where is the virtue in your reasoning, which relies on a speculation that "deep reasons we currently do not understand" are the reason why the universe is either "improbable" or "unremarkable", as the case may be? What evidence supports your speculation that such deep reasons exist?

Another flaw in your reaoning: The probabilities are not equal. probability supports an "unremarkable" universe. Given that we exist, an "unremarkable" universe is a more likely cause of our existence than an "improbable" universe.

And what would make the universe we observe "unremarkable"? An inflationary multiverse, in which everything possible almost certainly happens. There's a "deep reason" for you, and observations are consistent with it.

And what kind of universe is "improbable"? One with invariable parameters. Because we see no evidence that the parameters are invariable. However, we do see one example of a universe with existentially convenient parameters.

 

[tsig]

I only went down to post 24.

Apparently when you say fine tuning you mean just what you want to mean and no more.

Doesn't everyone? Seems like a waste of time to try to mean what you don't want to mean. Do you do that often?
>snip<
.

No most of us use the common meaning of the word but I see you prefer Humpty Dumpty's method.

“When I use a word,’ Humpty Dumpty said in rather a scornful tone, ‘it means just what I choose it to mean — neither more nor less.’
’The question is,’ said Alice, ‘whether you can make words mean so many different things.’

’The question is,’ said Humpty Dumpty, ‘which is to be master — that’s all.”

 

[Kevin_Lowe]

Then where is the virtue in your reasoning, which relies on a speculation that "deep reasons we currently do not understand" are the reason why the universe is either "improbable" or "unremarkable", as the case may be?

To paraphrase Wittgenstein, the virtue is to explain to you that currently this problem is one we should pass over in silence, for there is nothing worth saying to say about it.

 

[Toontown]

To paraphrase Wittgenstein, the virtue is to explain to you that currently this problem is one we should pass over in silence, for there is nothing worth saying to say about it.

This "we" you're talking about does not include me. If you want to pass over in silence, that's easy to do. Just pass over in silence. You don't need me to help you pass over in silence.