Fine-Tuning Problem in Cosmology

[Dancing David]

I certainly overestimated how savvy the science forum is. But if people are asking me what "an unnatural universe" is, after I've given links specifically on the topic, I can't say I'm too surprised.

I am surprised that you use some vaguely defined quotes, without any rigor and then dance your little superiority dance.

So exactly and in science give us that definition of an unnatural universe.

So where exactly did Einstein define this term that your pop science article uses, did you actually research it? What is the source of this notion?

I was not condescending to you but you post is offensive.

 

[Dancing David]

I'm not doing anymore homework. The links I've given are excellent sources of information on this very topic!

You mean some pop science article you hide behind, what exactly did Einstein say and in what context?

Or do you just quote other people material and never research it? Are you sure that Einstein actually proposed such a thing?

But please continue to hide between other peoples words?

 

[Hercules Rockefeller]

Stenger is one.

Also did you answer teh question:

How many possible values exit between the fine tuned value of .0000000000000000000000000000000000000000000000000000000001 and .0000000000000000000000000000000000000000000000000000000002 ?

That's not the point. The point is that if you changed the value for the Cosmological Constant by even an incredible tiny amount, the universe as we know it would not have existed.

 

[MRC_Hans]

That's not the point. The point is that if you changed the value for the Cosmological Constant by even an incredible tiny amount, the universe as we know it would not have existed.

And the point is that even if astronomical odds might indeed be against it, it is here, and this is the reason we are having this discussion.

We are discussing this because we are here, not any other way around (hence the puddle analogy).

However, what we actually don't know is what the odds are. We don't know how wide the possible variation range is for ANY of these constants.

Hans

 

[Belz...]

Just so long as it's turtles all the way down.

Vats all the way outwards.

 

[Dr. Keith]

That's not the point. The point is that if you changed the value for the Cosmological Constant by even an incredible tiny amount, the universe as we know it would not have existed.

I think this is what he is getting at. If the range of possible values is even smaller than the amount of change that would be required then it could vary freely (some would say an infinite number of values) within its small range of possible values without ever venturing into a value that prevents the universe from existing.

If you can't define the possible range then you really don't know that the required change is small. Much less an incredibly tiny amount.

 

[Dr. Keith]

Vats all the way outwards.

Turtle vats and I'll be happy. Even Alien Turtle Vats. (Band name?)

 

[tsig]

That's not the point. The point is that if you changed the value for the Cosmological Constant by even an incredible tiny amount, the universe as we know it would not have existed.

Then you would not exist to make this post, since you did make the post we know that it did not change. You are trying to make book on a completed race.

Who could make that change?

 

[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?

Fine tuning looks a lot like the privileged planet hypotheses.

It is just ID on a larger level than bacteria tails.

 

[Hercules Rockefeller]

I'm just saying it's a mystery and there's a number of ways to deal with the problem i.e. anthropic reasoning, the multiverse or other unknown possibilities. No one knows.

 

[turingtest]

And the point is that even if astronomical odds might indeed be against it, it is here, and this is the reason we are having this discussion.

We are discussing this because we are here, not any other way around (hence the puddle analogy).

However, what we actually don't know is what the odds are. We don't know how wide the possible variation range is for ANY of these constants.

Hans

I've never understood the "odds" argument anyway. As others have said, odds aren't applicable to a past process or events. Another way to look at it is this-

If you take a deck of 52 ordinary playing cards, and lay them out one by one face-up, the odds against any one predicted and specified outcome for the completed order of the cards- an aim- would be 1 in 8x10^67th (that is, 1 in 80 followed by 67 zeroes). If, however, you specify no outcome, but simply lay them out, with each outcome being as acceptable as any other, then odds don't matter anymore- each outcome is as likely as any other when each is as acceptable.

This is the way the non-normative processes of the universe work; that the outcome was one in which life was a result doesn't make it less likely when no outcome was specified to begin with. "Odds" simply doesn't apply, to either a past event or to a non-normative process (since the whole point of "odds" is to treat an outcome normatively, as a predicted and specified one). If the universe were to begin all over again- if the cards were laid out again, with no aim for the final lay- the outcome would probably be completely different; but that doesn't, by itself, make the outcome we do have, for the cards or for the universe, a less likely one.

You can certainly interpret the "fine-tuning" of the universe to mean there was design by intent with life as its goal; but, on the evidence alone, there's no reason to see life as anything other than an outcome of the universe, not its aim. The parameters of the universe make the tune that life dances to, but doesn't dictate.

 

[Dancing David]

That's not the point. The point is that if you changed the value for the Cosmological Constant by even an incredible tiny amount, the universe as we know it would not have existed.

Then apparently you didn't understand my question, say that the Cosmological Constant ( I assume you mean lambda), can vary between .00000000000000000000001 and .00000000000000000000002, how many potential values for lambda exist between the variance?

Did you read Stengers .pdf ?

 

[Hercules Rockefeller]

Then apparently you didn't understand my question, say that the Cosmological Constant ( I assume you mean lambda), can vary between .00000000000000000000001 and .00000000000000000000002, how many potential values for lambda exist between the variance?

Did you read Stengers .pdf ?

I get the argument, I just disagree with it.

If someone fires a gun and misses your head by an inch, I don't think you'll be saying he missed you by an infinite distance.

 

[Fudbucker]

I've never understood the "odds" argument anyway. As others have said, odds aren't applicable to a past process or events. Another way to look at it is this-

If you take a deck of 52 ordinary playing cards, and lay them out one by one face-up, the odds against any one predicted and specified outcome for the completed order of the cards- an aim- would be 1 in 8x10^67th (that is, 1 in 80 followed by 67 zeroes). If, however, you specify no outcome, but simply lay them out, with each outcome being as acceptable as any other, then odds don't matter anymore- each outcome is as likely as any other when each is as acceptable.

This is the way the non-normative processes of the universe work; that the outcome was one in which life was a result doesn't make it less likely when no outcome was specified to begin with. "Odds" simply doesn't apply, to either a past event or to a non-normative process (since the whole point of "odds" is to treat an outcome normatively, as a predicted and specified one). If the universe were to begin all over again- if the cards were laid out again, with no aim for the final lay- the outcome would probably be completely different; but that doesn't, by itself, make the outcome we do have, for the cards or for the universe, a less likely one.

You can certainly interpret the "fine-tuning" of the universe to mean there was design by intent with life as its goal; but, on the evidence alone, there's no reason to see life as anything other than an outcome of the universe, not its aim. The parameters of the universe make the tune that life dances to, but doesn't dictate.

You're confusing the probability of an event (what happened), which is 1, since it already happened, with the probabilities of all the possible explanations for the event (why it happened), which fall between 0 and 1.

Consider: you walk up to a poker table, just as all the other players are leaving. You ask why they're leaving. They tell you the dealer just dealt himself a fourth royal flush in a row. The dealer confirms this, but claims he's just lucky. The odds of the four royal flushes are 1, since the events already occurred before you even got there. However, the "chance" explanation fails because the outcome is much better explained by a "cheating" hypothesis, than random chance alone. If you don't agree, then just change "four royal flushes" to "40 royal flushes". The point is, eventually you reach a point where the "chance" hypothesis is totally inadequate and another explanation is required, even though the event already occurred.

Also consider: a country decides to give a condemned person a chance at a pardon. The condemned will write down a number between one and 100 quadrillion. Right before the execution, the state will generate a random number between one and 100 quadrillion.

You are the condemned person, and this is the first time the state has ever done this. You've written down your number and are waiting for the cyanide pellet to drop after the state generates it's random number. The pellet never drops. Since you survived, the odds of you surviving the event are 1. However, you would naturally wonder why you're alive, and in a short time be convinced that someone intervened on your behalf, because the chance hypothesis is trumped massively by the hypothesis that someone rigged the new system on your behalf.

In the same way, we find ourselves in a universe that is appearing more and more unnatural (the values of the physical constants are not the result of any natural law, but random chance). We also know that if we tweak any of at least a dozen numbers by even a tiny amount, life that fits even the weirdest definition of "life" would not be possible (e.g., no life would exist in a universe where molecules can't form, or a universe that collapses back in on itself in a millisecond). The creation of the universe has a probability of 1, since it already happened. However, like the condemned man wondering how he could have possibly survived, we exist and we wonder how we could possibly be here, when the odds of a universe supporting any kind of life were so low.

If there's no natural explanation, then there are either a whole lot of condemned men (i.e., a lot of universes), and we just got lucky, or something intervened on our behalf (or we exist in a simulation in a universe that doesn't have a fine-tuning problem).

 

[John Jones]

You're confusing the probability of an event (what happened), which is 1, since it already happened, with the probabilities of all the possible explanations for the event (why it happened), which fall between 0 and 1.

[...]

So what is your explanation?

 

[tsig]

You're confusing the probability of an event (what happened), which is 1, since it already happened, with the probabilities of all the possible explanations for the event (why it happened), which fall between 0 and 1.

Consider: you walk up to a poker table, just as all the other players are leaving. You ask why they're leaving. They tell you the dealer just dealt himself a fourth royal flush in a row. The dealer confirms this, but claims he's just lucky. The odds of the four royal flushes are 1, since the events already occurred before you even got there. However, the "chance" explanation fails because the outcome is much better explained by a "cheating" hypothesis, than random chance alone. If you don't agree, then just change "four royal flushes" to "40 royal flushes". The point is, eventually you reach a point where the "chance" hypothesis is totally inadequate and another explanation is required, even though the event already occurred.

Also consider: a country decides to give a condemned person a chance at a pardon. The condemned will write down a number between one and 100 quadrillion. Right before the execution, the state will generate a random number between one and 100 quadrillion.

You are the condemned person, and this is the first time the state has ever done this. You've written down your number and are waiting for the cyanide pellet to drop after the state generates it's random number. The pellet never drops. Since you survived, the odds of you surviving the event are 1. However, you would naturally wonder why you're alive, and in a short time be convinced that someone intervened on your behalf, because the chance hypothesis is trumped massively by the hypothesis that someone rigged the new system on your behalf.

In the same way, we find ourselves in a universe that is appearing more and more unnatural (the values of the physical constants are not the result of any natural law, but random chance). We also know that if we tweak any of at least a dozen numbers by even a tiny amount, life that fits even the weirdest definition of "life" would not be possible (e.g., no life would exist in a universe where molecules can't form, or a universe that collapses back in on itself in a millisecond). The creation of the universe has a probability of 1, since it already happened. However, like the condemned man wondering how he could have possibly survived, we exist and we wonder how we could possibly be here, when the odds of a universe supporting any kind of life were so low.
If there's no natural explanation, then there are either a whole lot of condemned men (i.e., a lot of universes), and we just got lucky, or something intervened on our behalf (or we exist in a simulation in a universe that doesn't have a fine-tuning problem).

Actually the odds of a universe supporting life are one since we are in one of those.


Who did your fine tuning?

 

[Fudbucker]

So what is your explanation?

What, I didn't make any grammar mistakes*?

There are several explanations:

1. Coincidence. Other than Victor Stenger, I haven't seen any evidence that any scientists actually doing research chalk it up to this. The number of scientists who have a problem with the coincidence explanation is long and illustrious. People like Tegmark, Linde, Hawking, Rees, Davies, Dyson** are all highly respected in their fields.

Their reasoning is fairly straightforward- the universe appears to be balanced on a knife-edge for life to even be possible. If universes where life is possible are extremely (almost impossibly) rare, and yet we find ourselves in one, the question is obvious- did we win a highly unlikely cosmic jackpot or was something else at work?

2. The values are the result of some natural law, like super-symmetry (or some theory that hasn't even been thought of yet). It would be nice if we could derive all the values from some elegant theory, but since the LHC, a natural explanation doesn't seem likely anymore.

3. A sufficiently large multiverse. This is what seems to be popular at the moment, especially with BICEP2's recent findings supporting inflation. Given enough universes, there would be a few life-permitting ones, and we happen to be on one of them.

4. A simulation where the problem is non-existent in the unsimulated "real" universe. Nick Bostrom has a theory that there are decent odds we're in a simulation anyway. If multiverse-theory doesn't pan out, simulation-theory will get a boost.

5. The existence of a fine-tuner. The fine-tuner would have to come from outside the universe (otherwise the problem is just bumped up a level), so you'd basically be dealing with a supernatural explanation. I reject this because there is scant evidence a supernatural being exists.

If the coincidence explanation isn't satisfactory, then fine-tuning is a "problem". But "problem" simply means a surprising result that needs to be explained. It can be something as mundane as the hexagon cloud-structure on Saturn (nobody is suggesting coincidence for that one either), or as problematic as Mercury's eccentric orbit wrt to Newtonian Physics.

As cosmologist Paul Davies puts it: "There is now broad agreement among physicists and cosmologists that the universe is in several respects ‘fine-tuned' for life."

I think why so many people voted "no" is because the creationists have gleefully hitched their wagon to the supernatural explanation, and now cosmic fine-tuning has a ton of theistic "baggage" associated with it. Just because coincidence is unsatisfactory doesn't mean "god did it".

David, I don't hide behind quotes. I've explained my reasoning why the "puddle analogy" doesn't work. I use quotes to show that many, many authorities agree with my position. This is not a fallacy, as the authorities are all respected authorities in the relevant field.




*I still don't get the Africa thing

** "As we look out into the universe and identify the many accidents of physics and astronomy that have worked together to our benefit, it almost seems as if the universe must in some sense have known we were cominghttp://en.wikiquote.org/wiki/Freeman_Dyson."

 

[Fudbucker]

Actually the odds of a universe supporting life are one since we are in one of those.

Again, there is a difference between the probability of an event (1), and the probabilities of the explanations for the event (between 0 and 1).

Who did your fine tuning?

A fine-tuner isn't required for several explanations.

 

[Kevin_Lowe]

You're confusing the probability of an event (what happened), which is 1, since it already happened, with the probabilities of all the possible explanations for the event (why it happened), which fall between 0 and 1.

Consider: you walk up to a poker table, just as all the other players are leaving. You ask why they're leaving. They tell you the dealer just dealt himself a fourth royal flush in a row. The dealer confirms this, but claims he's just lucky. The odds of the four royal flushes are 1, since the events already occurred before you even got there. However, the "chance" explanation fails because the outcome is much better explained by a "cheating" hypothesis, than random chance alone. If you don't agree, then just change "four royal flushes" to "40 royal flushes". The point is, eventually you reach a point where the "chance" hypothesis is totally inadequate and another explanation is required, even though the event already occurred.

The problem with this analogy is that we do know that poker cheats exist, and we also know that four royal flushes in a row is improbable.

Compared to a real thing like a poker cheat the hypothesis "something maybe God fine-tuned the universe to create life like us" is not a hypothesis with any explanatory power.

Worse, we don't even know that the universe we are in is improbable in any meaningful sense. Maybe this is the only way a universe can be.

Here's a different analogy for you. The odds of me personally existing are unimaginably tiny. Out of millions of sperm just the right one had to get to the egg first, and the same for both my parents, and the same for all my parents and great-grandparents and so on. If at any time any other sperm had won the race I wouldn't be here. Forgetting every other contingency that led to me being alive today to post it, that improbability alone is staggering. Yet I am not surprised by the fact that I exist, nor do I think it in need of any particular explanation.

After all, if I didn't exist I wouldn't be here to marvel at my own improbability.

In the same way, maybe the universe isn't improbable. However even if it is, only in that subset of cases where life arises will life wonder at how convenient it is that life exists. Hence living things should not be the least bit surprised that the universe they are in supports life.

 

[Correa Neto]

Some things must be added to the fact we have few if any clues about possible different values of the constants and possible different universes.

First, along the lines of what Kevin Lowe wrote, “god or alien turtles did it” lack explanatory power. It just hides the problems under the rug creating a huge hump underneath it. How god or the alien turtles did it? How god or the alien turtles came to be?

Second, science is an eternal WIP. Consider how many models have been proposed and tested within cosmology. So, the interpretation of LHC data being questioned is normal and expected. The future outcome may or may not be aligned with supersymmetry. Similar reasoning can be applied to multiverse lines of investigation. Constants tailored for life, well, guess what? This notion can also be questioned and changed.

Third, we must keep an unbiased perspective. Can we actually say the universe –or even our own Goldilocks planet- is fine tuned for us? Consider the following: For how long would last an average human if dropped at a randomly chosen part of the Earth’s surface? Now, lets change perspective and substitute “human”, say, by “tardigrade”. Maybe Earth was actually fine-tuned for tardigrades and we are just enjoying the ride…

For how long would an average human last if dropped at a randomly chosen part of the universe? And a tardigrade, for how long would it last? So, it seems finely tuned constants apart, most of the universe is rather hostile for life. If you add time as a factor to this observation, then you’ll see that according our current understanding of the universe, we are living at the very narrow window of time and space where life-as-we-know-it-Jim is possible. If it’s a simulation… Looks like a waste of resources and rather poor coding. Why not simulate the whole damn thing in a smaller volume of space and time(*)? Why not say, 6Ky-old small geocentric universe where conditions suitable for life will last forever?

I think we can’t actually say the universe was somehow tailored for human life; it’s just another version of the narrow, biased anthropocentric views inherited from religious doctrines that place mankind at the center of the stage and under a bright spotlight. Life, more specifically human life was a consequence, a side effect, rendered possible by sheer chance when conditions were favorable and a given complex long chain of events happened. Life (human life included) could as well not have happened at all. So, again, sorry but… Tuned for life? Meh! Deal with it. Live long and prosper.



(*)OK, maybe it’s the only way. But lets suppose it’s a simulation. Sorry, but meh, again. The alien turtles may be running countless simulations and this may be just one. Maybe life is just an unintended, unexpected side effect (perhaps even undesirable). Or they are right now annoyed because turtles have not evolved to become a sentient species at this iteration. In light of this result, some alien turtles are wondering that their universe must be a simulation, because the conditions were the right ones and the whole chain of events unfolded precisely as required for their species coming in to existence. Wait, maybe large areas of this simulated galaxy are being colonized by alien turtles right now, just as it happened in the turtleverse. Thus, the alien turtles (simulations and simulators) are wondering that their universe must be a simulation, because the fine-tuned constants and the whole chain of events unfolded precisely as required for their species coming in to existence. See? Cheloniocentrism…