The fine tuning problem in physics is an observation that multiple fundaental physical constants seem to independently fall into relatively small intervals enabling the existence of life.
The Strong Anthropic Principle is a proposed explanation for fine tuning which posits the existence of multiple universes or parts of the universe with different values of basic constants. In a multiverse like that we necessarily find ourselves in the part which support the existence of life and consciousness.
Each option in this question will be resolve based on one of the following:
If a poll is conducted among physicists about the most likely explanation for fine-tuning, its results are used directly. The poll should be reasonably representative.
In absence of such poll, I'll try to find at least 2 professional physicists (preferably Manifold users) and ask them whether in their opinion Anthropic Principle is the preferred explanation of fine tuning among physicists. Note: I will not be asking whether they personally believe this explanation, but whether it's the preferred explanation in the field.
If previous options don't resolve the question, I'm going to ask the best available at the time version of ChatGPT or another AI, whether they think Strong Anthropic Principle is accepted as most likely true in physics community.
As soon as one of these methods unambiguously point to Strong Anthropic Principle being accepted, I'll resolve all remaining options to YES. Otherwise the options will resolve to NO as soon as the respective period is over.
Astronomers and cosmologists count as physicists for the purposes of this question. Philosophers do not, except those that also hold a PhD in Physics or Astronomy.
In case the research in Physics gets dominated by AIs, I will try to adapt the resolution criteria to gauge their opinions. If this is for some reason impossible, I might resolve some of the options as N/A.
I do not bet on my own questions.
Update 2026-01-07 (PST) (AI summary of creator comment): For the Strong Anthropic Principle to be accepted as the most likely solution for fine-tuning, physicists must consider it likely that we live in a multiverse with varying cosmological constants. Without assuming the existence of a multiverse, the Strong Anthropic Principle does not resolve the fine-tuning question.
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@spiderduckpig To accept the anthropic principle as the most likely explanation, the majority of physicists should also consider it likely that we live in a multiverse with varying cosmological constants. And this proposition is pretty controversial.
@OlegEterevsky I don't think varying cosmological constants or non fine-tuned multiverses is necessary for anthropic reasoning to apply, only that 1. certain cosmological constants exist in our universe, and 2. the values that they're at are uniquely suited to allowing for emergent behaviors like life. For example, the constant Λ is very fine tuned and a slightly smaller or greater value would make life impossible. I'm sure if you asked most physicists why this value is so perfectly fine-tuned, they would agree with the explanation that rational observers would be impossible to exist without a perfectly fine tuned value, so it would be impossible to observe a non-fine tuned value.
@spiderduckpig If we don't assume the existence of a multiverse, then the question of why the constant Λ has the value that it does is still open, no? Strong Anthropic principle doesn't resolve it.
@OlegEterevsky How so? The question "why do we observe Λ to have a certain fine-tuned value" is solved by an anthropic explanation. If you're asking "what was the efficient cause of a universe having this value, regardless of our presence of it," I don't think anthropic reasoning is applicable or related to that question
@spiderduckpig If we live in a multiverse with a varying value of a given parameter, it removes the question of why the parameter has this particular value. So it does solve the question.