And recent DESI data suggests that dark energy is not constant and the universe will experience a big crunch in a little more than double its current age, for a total lifespan of 33 billion years, no need to get wild with the orders of magnitude on years into the future. The infinite expansion to heat death over 10^100 years is looking less likely, 10^11 years should be plenty.

https://www.sciencedaily.com/releases/2026/02/260215225537.h...

Protons can decay because the distinction between matter and energy isn't permanent.

Two quarks inside the proton interact via a massive messenger particle. This exchange flips their identity, turning the proton into a positron and a neutral pion. The pion then immediately converts into gamma rays.

Proton decayed!

This was my thought. Nanoseconds are an eternity. You want to be using Planck units for your worst-case analysis.

Nanoseconds is a natural unit for processors operating around a GHz, as it's roughly the time of a clock cycle.

If a CPU takes 4 cycles to generate a UUID and the CPU runs at 4 GHz it churns out one every nanosecond.

> many worlds interpretation

These are only namespaces. Many worlds can have all the same (many) random numbers and they will never conflict with each other!

In that interpretation the total number of worlds does not change.

We don't "make" universes in the MWI. The universal wavefunction evolves to include all reachable quantum states. It's deterministic, because it encompasses all allowed possibilities.

Conservation laws result from continuous symmetries in the laws of physics, as proven by Noether's theorem.

So is the need for cosmologically unique IDs. We're having fun.

Times for things like "age of the universe" are usually given as "cosmic time" for this reason. If it's about a specific object (e.g. "how long until a day on Earth lasts 25 hours") it's usually given in "proper time" for that object. Other observers/reference frames may perceive time differently, but in the normal relativistic sense rather than a "it all needs to wind itself back up to be equal in the end" sense.

The local reference frame (which is what matters for proton decay) doesn't see an outside world moving slower or faster depending on how much mass is around it to any significant degree until you start adding a lot of mass very close around.