1 upvotes, 1 direct replies (showing 1)
View submission: Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science
There are those who interpret the evidence of random variations at the quantum level as evidence of parallel universes. Though this is of course quite debatable.
The most important lesson I learned from the statistics class is that, while a single random event is completely unpredictable by definition, the aggregate of many occurrences of a random event is quite predictable if you know the probability distribution. Throw a coin 10,000 times, it's practically impossible that you'll get 55% or more faces. It will be much closer to 50-50 and I'm ready to bet all my savings on that.
So, my speculation: if those random quantum variations were really caused by parallel universes, at the macroscopic level those other universes would be exactly identical to ours becase what we see macroscopically is the aggregate of a lot of random microscopic events.
What do the physicists of reddit think of this speculation?
Edit: for the purposes of defining "exactly identical" consider everything that can be measured without getting down to the microscopic level
Comment by jarebear at 07/12/2023 at 02:06 UTC
4 upvotes, 0 direct replies
There's a few things off with this analogy. First, it's possible there are other universes with different fundamental physical constants so that obviously would lead to a different universe.
Second, chaos theory shows that extraordinarily small changes can lead to radically different behaviors in complex systems. Going back to the analogy, we're not just flipping 10,000 coins and then calling it a day on the universe, the difference between 4,999 heads and 5,000 could eventually lead to fundamentally different results.
Third, and one that directly deals with the analogy, is that there is a non-zero chance of getting over 55% heads in 10,000 coin tosses. It's incredibly low but with infinite universes where you make that bet, there are universes where you lose your savings on that bet (in fact, infinitely many). Hell, 1 in ~10^3010 universes have you lose that bet with 100% of the coins coming up heads. Now that's a ridiculous set of odds, you have a better shot of picking the "lucky proton" out of the 10^80 in the observable universe, but if you're talking infinite (or a quick Google result of maximum 10^10^16 universes) then it's likely or certain to happen.