> In fact it's quite hard for something random at that level to have any noticeable [to a human] effect at all. So basically all the multiverses are identical.

> In fact it's quite hard for something random at that level to have any noticeable [to a human] effect at all. So basically all the multiverses are identical. If and what particular type of tissue damage and/or cancer(s) is caused in someone by exposure to radiation damaging their cells in repairable or unrepairable ways (which depends on the particular times at which particular radioactive atoms decay and the paths of the resulting particles and their interactions with with the small-scale constituents of the person's biology). I would think that whether a person recovers from some radiation exposure or the exposure went just beyond what their cells could handle and thus causes a fatal cancer, that is noticeable to a human. Finding that wasn't altogether hard. Given a sufficiently long time horizon (some physicists at UC Davies got some press arguing it could be on the scale of months), future weather conditions at individual moments are currently in the realm of quantum uncertainty/randomness. The people who have/don't-have car accidents due to the rain&sleet or not on some winter day a few years hence will easily notice which of the multiple worlds they ended up in. Also, should anyone so choose, they could easily make world-history-scale decisions based on Geiger counter readings or some other implementation of a quantum-coin-flip. Imagine an assassin setup and ready to take out a large nation's leader(s), and taking the shot or not based on such a random quantum outcome. Scale is no barrier to such things.