A Why the fine-tuning argument for improbable existence is a fallacy

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"In 1961, physicist Robert H. Dicke claimed that certain forces in physics, such as gravity and electromagnetism, must be perfectly fine-tuned for life to exist anywhere in the universe. Fred Hoyle also argued for a fine-tuned universe in his 1984 book Intelligent Universe.
Much as been written about the precise parameters allowing human being to exist, such that if the values were different, humans and life of similiar organic matter would not exist."


Now, here's the caveat; this observation does not tell us anything more than that the conditions conducive to the intelligent we know of is the one which we are currently apart of (surprise!). The universe would have to take some value, and unless you can prove that the observable universe we are apart of was a singular event in history, "the fine-tuning argument" is not an argument for any innate improbability of our existence.

If the big bang was not a singular event, our universe would have to evolve in one of the universes coming in and out existence due to the principle of physics "anything that can happen, will eventually happen". If that principle is not enough motivation for you, quantum physics neccessitate there to arrise a universe with the values that we currently live in. It's just a matter of "time", or if you like, enough "trials".

If the Big Bang was a singular event and there are no appeals to a multiverse hypothesis, one would first have to prove that the universe had an absolute beginning in order to derive that the values we end up with conducive to propagate our life was improbable, rather than a brute fact (otherwise there would be no use in applying probability models ), and that physics is an ultimately inadequate method of inquiry.

We have not even remotely reached that stage in our understanding of the universe.

Is there anyone reading this that would object to this rather straight-forward approach to a "problem" which may very well be imaginary?
 
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Dr. Courtney

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Usually, ideas and hypotheses that consider other universes and what might happen in them are outside the scope of science, because they are not falsifiable (not testable). These scientific-sounding speculations are not really scientific, because they do not make testable predictions. But likewise, many rebuttals also fail to make testable predictions. One can only use the scientific method and common approach to asking for supporting (or refuting) experimental evidence for hypotheses that are falsifiable in the first place.

Explanations don't always make testable predictions, and the fine-tuning argument and many of its rebuttals are in this category. So it's not so much that it's a logical fallacy (since the versions I've heard are offered as support rather than proof), it's outside the scope of science.
 

BWV

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Ultimately the ‘why are we here?’ and ‘why is there something rather than nothing?’ questions, which the fine tuning arguments address, belong to philosophy, not science. Nothing wrong with philosophy informed by science, but the distinction needs to be made. We can only know the universe as it presents to us and will never get an adequate answer why it exists in this form vs some other.
 
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Usually, ideas and hypotheses that consider other universes and what might happen in them are outside the scope of science, because they are not falsifiable (not testable).
It is science and falsifiable if it's explicitly compliant with Quantum Mechanics, which the multiverse hypothesis is. It wouldn't have been with our knowledge prior to quantum mechanics. Thus the theory would have been falsified if QM was not a correct model of reality. This is why many physicists are tempted to embrace it.

There are also possible indirect evidence of the multiverse:

"It sounds bonkers but the latest piece of evidence that could favour a multiverse comes from the UK’s Royal Astronomical Society. They recently published a study on the so-called ‘cold spot’. This is a particularly cool patch of space seen in the radiation produced by the formation of the Universe more than 13 billion years ago."

One of the study’s authors, Professor Tom Shanks of Durham University, told the RAS, “We can’t entirely rule out that the Spot is caused by an unlikely fluctuation explained by the standard [theory of the Big Bang]. But if that isn’t the answer, then there are more exotic explanations. Perhaps the most exciting of these is that the Cold Spot was caused by a collision between our universe and another bubble universe. If further, more detailed, analysis … proves this to be the case then the Cold Spot might be taken as the first evidence for the multiverse.”
 
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Ultimately the ‘why are we here?’ and ‘why is there something rather than nothing?’ questions, which the fine tuning arguments address, belong to philosophy, not science. N
That is NOT the topic of the discussion raised here. The topic is the assumption that our existence is improbable based on mathematical models of possible universes. It is true that our existence only fit within a narrow range of parameters, but it does not entail that it is therefore an unlikely event, unless we know about the frequency of past universe formations. The first step to this realization is whether such theories are mathematically consistent and in line with the findings of quantum mechanics - the behavior at subatomic levels.
 
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BWV

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The first step to this realization is whether such theories are mathematically consistent and in line with the findings of quantum mechanics - the behavior at subatomic levels.
That is not only the first step, but also likely the last - after which is only speculation.
 
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That is not only the first step, but also likely the last - after which is only speculation.
And QM prescribes that a universe can, in fact WILL pop into existence from rudimentary conditions. This is the consequence/prediction of the theory, and it is the most verified theory in physics. No reason then not to assume that is the origin of the universe(s), concidering the postulate: "everything that can happen, will happen"
 

kimbyd

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Among physicists, "fine tuning" is usually considered to be a guide to ways in which our understanding is incomplete. There's a general expectation that the appearance of fine tuning is an indication that something is going on that we don't really understand. It's not an unreasonable stance to take: if you were walking down the sidewalk and came across a pencil standing on its tip in the middle of the sidewalk, you'd expect there to be a reason for it. You wouldn't expect it to just have been the result of a pencil falling out of somebody's pocket and landing that way. That can happen, but it's very unlikely.

So fine tuning is generally not considered to be something we can conclude with certainty that there must be an explanation we don't yet understand, but theorists hope that it provides a guide to places that current theories may need to be modified. Much of the debate surrounding fine tuning seems to revolve around how much fine tuning we should expect to see, resulting in a lot of anthropic principle arguments which tend to be highly controversial.

Physicists generally don't think fine tuning says anything about existence. It's all about highlighting potential incorrectness in the physical laws as we understand them today, and thus guiding theorists to modifications that might be better descriptions of reality.

And yes, there is a lot of debate as to whether or not fine tuning should be used as a guide at all.
 
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Among physicists, "fine tuning" is usually considered to be a guide to ways in which our understanding is incomplete. There's a general expectation that the appearance of fine tuning is an indication that something is going on that we don't really understand. It's not an unreasonable stance to take: if you were walking down the sidewalk and came across a pencil standing on its tip in the middle of the sidewalk, you'd expect there to be a reason for it. You wouldn't expect it to just have been the result of a pencil falling out of somebody's pocket and landing that way. That can happen, but it's very unlikely.
The inference here is that our existence, if astronomically improbable, could reveal additional layers of complexity to the universe. But the inference that our existence is astronomically improbable is a premature conclusion based on the data. We don't have a working model for the prior probability of a universe existing/coming into existence due to incomplete theories on cosmology.
 

kimbyd

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The inference here is that our existence, if astronomically improbable, could reveal additional layers of complexity to the universe. But the inference that our existence is astronomically improbable is a premature conclusion based on the data. We don't have a working model for the prior probability of a universe existing/coming into existence due to incomplete theories on cosmology.
Except we do have a model: the standard model. The point is that the appearance of fine tuning is one indication that the standard model is incomplete.

Fine tuning is a useful concept only in relation to specific theoretical models. The observation that those theoretical models can be incomplete and therefore the fine tuning might go away if we had a better model is the entire point of the exercise.
 
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Except we do have a model: the standard model.
The standard model is that the observable universe started at a certain point, dubbed the big bang. It lacks any cohesive theory beyond that. There is good reason to believe, based on QM, that fundamental reality beyond bing bang(s) is QM frequencies that give rise to universes. Do you see any reason not to accept such a world view when QM clearly shows that such behavior is permissible?
 

kimbyd

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The standard model is that the observable universe started at a certain point, dubbed the big bang. It lacks any cohesive theory beyond that. There is good reason to believe, based on QM, that fundamental reality beyond bing bang(s) is QM frequencies that give rise to universes. Do you see any reason not to accept such a world view when QM clearly shows that such behavior is permissible?
"QM frequencies" is gibberish. Please rephrase using words that have real meaning.
 

kimbyd

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Quantum vacuum, of course.
Quantum vacuum fluctuations, you mean? That's one class of models. There are many others.

But you don't specifically need a particular model for the origin to talk about fine tuning. It's possible to discuss fine tuning for any model. Yes, some fine tuning might disappear if you add a particular model for the origin to the standard cosmological model. That's the point of examining the fine tuning!
 

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