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The anthropic principle in its weak form isn't really a hypothesis - it's more of a methodological principle that warns us against unnecessary theories. This is

The anthropic principle in its weak form isn't really a hypothesis - it's more of a methodological principle that warns us against unnecessary theories. This is best illustrated by the historical debate between Dirac and Dicke (who came up with this idea) about cosmic coincidences. In 1937, Dirac noticed striking numerical relationships between fundamental physical constants and the age of the universe [1]. He proposed these couldn't be coincidental and suggested fundamental constants must vary with cosmic time. But Dicke (1961) showed that some of these "coincidences" weren't so mysterious: they were necessary conditions for our existence as observers [2]. The universe had to be old enough for heavy elements to form in stars, but not so old that all stars burned out. These constraints naturally explain some of the numerical relationships Dirac found, without requiring varying constants. However, Dicke's argument has limits: it only works for coincidences necessary for intelligent life. It can't explain away "gratuitous coincidences" - numerical relationships that aren't required for our existence. This is particularly relevant because Dirac's work was actually part of a longer tradition - going back to Weyl in 1919 [1] - of physicists finding peculiar numerical relationships between physical constants. While the article discusses coincidences that make our existence possible, we need to consider how to explain the other ones. Is it even feasible ? Let me give it a try. If physical constants were "set" randomly, with their observability conditioned only by whether they allow intelligent life, we should expect to find both types of coincidences in our universe: the necessary ones that enable our existence, and gratuitous ones that just happened to come along for the ride in our universe's "roll of the dice". This leads to a disturbing conclusion: for laws of physics to be discoverable by observers in a universe without a creator, they must contain misleading elements as a by-product of what allowed these observers to emerge. The universe seems to impose a double-bind on its observers - the very conditions that make it observable must also make it deceptive. [1] https://en.wikipedia.org/wiki/Dirac_large_numbers_hypothesis https://en.wikipedia.org/wiki/Dirac_large_numbers_hypothesis https://en.wikipedia.org/wiki/Anthropic_principle https://en.wikipedia.org/wiki/Anthropic_principle [2] https://en.wikipedia.org/wiki/Anthropic_principle#Anthropic_observations https://en.wikipedia.org/wiki/Anthropic_principle#Anthropic_...

DennisP 2y ago
Here's a counterargument. Let's say there are two possible coincidences, A and B, each with an independent one-in-a-million chance. Coincidence A is necessary for life to emerge, but B is irrelevant. Now let's say there are a trillion universes, with random settings. Only one in a million universes have coincidence A, but those are all the universes with observers. All the observers see coincidence A. Out of those million universes, we can expect to see only one universe with coincidence B. The vast majority of observers will only see the coincidence that allowed them to exist.
- soulofmischief 2y ago
  But how can you determine that you're not one in a million?
  - DennisP 2y ago
    You can't, not for sure. But this does mean that we shouldn't expect to find gratuitous coincidences. Most likely, the apparent coincidences we observe in physics and cosmology will either be necessary, due to physical relationships we don't understand yet, or will be explainable by the anthropic principle.
    - soulofmischief 2y ago
      Would being one in a million itself be a coincidence though, one which we couldn't differentiate from coincidences explainable by the anthropic principle? "Most likely" doesn't satisfy me. It's easy to form conjectures, but there is a deep metaphysical problem when it comes to satisfactorily modeling a system from the inside. It's turtles all the way down [0]. Unless our universe is embedded within another system, and its configuration at least partially mirrors the configuration of the system it is embedded within [1], and this is recoverable, then we really just can't make many absolute claims about the nature of our universe's particular configuration. [0] And the only way out is by solving the deepest metaphysical problems which physics has not been able to touch, such as, "Why is there anything at all?" [1] An example might be the conservation of energy, or stationary action. If such principles were to hold even within a system our universe might be embedded in, we could start to narrow down a few things and maybe uncover some suprauniversal inevitabilities. The challenge is proving that without observing the universe from the vantage point of a host system, which would really mean proving the inevitability of such principles in any system of sufficient complexity.

DennisP 2y ago

Here's a counterargument. Let's say there are two possible coincidences, A and B, each with an independent one-in-a-million chance. Coincidence A is necessary for life to emerge, but B is irrelevant. Now let's say there are a trillion universes, with random settings. Only one in a million universes have coincidence A, but those are all the universes with observers. All the observers see coincidence A. Out of those million universes, we can expect to see only one universe with coincidence B. The vast majority of observers will only see the coincidence that allowed them to exist.

soulofmischief 2y ago
But how can you determine that you're not one in a million?
- DennisP 2y ago
  You can't, not for sure. But this does mean that we shouldn't expect to find gratuitous coincidences. Most likely, the apparent coincidences we observe in physics and cosmology will either be necessary, due to physical relationships we don't understand yet, or will be explainable by the anthropic principle.
  - soulofmischief 2y ago
    Would being one in a million itself be a coincidence though, one which we couldn't differentiate from coincidences explainable by the anthropic principle? "Most likely" doesn't satisfy me. It's easy to form conjectures, but there is a deep metaphysical problem when it comes to satisfactorily modeling a system from the inside. It's turtles all the way down [0]. Unless our universe is embedded within another system, and its configuration at least partially mirrors the configuration of the system it is embedded within [1], and this is recoverable, then we really just can't make many absolute claims about the nature of our universe's particular configuration. [0] And the only way out is by solving the deepest metaphysical problems which physics has not been able to touch, such as, "Why is there anything at all?" [1] An example might be the conservation of energy, or stationary action. If such principles were to hold even within a system our universe might be embedded in, we could start to narrow down a few things and maybe uncover some suprauniversal inevitabilities. The challenge is proving that without observing the universe from the vantage point of a host system, which would really mean proving the inevitability of such principles in any system of sufficient complexity.