Cosmologic philosophy: fine tuning and alternatives (Introduction)

by David Turell @, Monday, October 17, 2022, 20:36 (557 days ago) @ David Turell

A clear discussion:

https://uncommondescent.com/intelligent-design/from-the-new-atlantis-the-fine-tuning-of...

"Underlying all of these endeavors, however, is a question that has vexed physicists ever since Thales first postulated that water was the unifying principle of the cosmos: What are the most fundamental laws and principles of nature?

"Today, our deepest understanding of the laws of nature is summarized in a set of equations. Using these equations, we can make very precise calculations of the most elementary physical phenomena, calculations that are confirmed by experimental evidence. But to make these predictions, we have to plug in some numbers that cannot themselves be calculated but are derived from measurements of some of the most basic features of the physical universe. These numbers specify such crucial quantities as the masses of fundamental particles and the strengths of their mutual interactions. After extensive experiments under all manner of conditions, physicists have found that these numbers appear not to change in different times and places, so they are called the fundamental constants of nature.

"These constants represent the edge of our knowledge. Richard Feynman called one of them — the fine-structure constant, which characterizes the amount of electromagnetic force between charged elementary particles like electrons — “one of the greatest damn mysteries of physics: a magic number that comes to us with no understanding by man.” An innovative, elegant physical theory that actually predicts the values of these constants would be among the greatest achievements of twenty-first-century physics.

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"Since physicists have not discovered a deep underlying reason for why these constants are what they are, we might well ask the seemingly simple question: What if they were different? What would happen in a hypothetical universe in which the fundamental constants of nature had other values?

"There is nothing mathematically wrong with these hypothetical universes. But there is one thing that they almost always lack — life. Or, indeed, anything remotely resembling life.

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"That the constants are all arranged in what is, mathematically speaking, the very improbable combination that makes our grand, complex, life-bearing universe possible is what physicists mean when they talk about the “fine-tuning” of the universe for life.

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"The lack of an explanation for the fundamental constants in the Standard Model suggests that there is still work to be done.

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"...even a theory free of arbitrary constants would not necessarily explain why the universe gives rise to living beings like us. If these hoped-for deeper equations are anything like all the equations of physics thus far, then they, too, will still require initial conditions. The laws specify how the stuff of the universe behaves in a given scenario; they do not specify the scenario.

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"...rather than talking about the fine-tuning of the constants, we would consider the fine-tuning of the symmetries and abstract principles. Could it be just a lucky coincidence that they produce in our universe the properties and interactions required by complex structures such as life? This notion “really strains credulity,” according to Frank Wilczek, who shared the 2004 Nobel Prize in Physics with David Gross. And as Bernard Carr and Martin Rees wrote in the conclusion of an influential early paper on the fine-tuning problem, “it would still be remarkable that the relationships dictated by physical theory happened also to be those propitious for life.”

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"The fine-tuning of the universe for life invites us to imagine that our fortuitous cosmic environment is improbable. A random spin of the cosmic dials, it seems, would almost certainly result in a universe unable to create and sustain the complexity required by life. But if probabilities must be dictated by physical theories and are about physical events, as the frequentist believes, then we cannot say that our constants are improbable. We have no physical theory that stands above the constants, informing us that they are unlikely.

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"Facts can be special to a theory. That is, they can be special because of what we can infer from them. Fine-tuning shows that life could be extraordinarily special in this sense. Our universe’s ability to create and sustain life is rare indeed; a highly explainable but as yet unexplained fact. It could point the way to deeper physics, or beyond this universe, or even to principles beyond the ultimate laws of nature."

Comment: The article is filled with examples of what could go wrong if constants are changed. Multiverses can be calculated but not studied and are dismissed. The anthropic principle is not mentioned but a John Leslie quote is: "[theories]include axiarchism, the view that moral value, such as the goodness of embodied, free, conscious moral agents like us, can explain the existence of one kind of universe rather than another; or, in the words of John Leslie, the theory’s chief proponent, it is “the theory that the world exists because it should.'”


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