What a nice little war. Technically Bruce is right, but this just shows that we have misunderstood the issue. Of course mass/energy in each branch is unaffected by the split; we just need to find another, sane way to express the idea.
Here is what I understand; correct me if I am wrong. In the multiverse created by a single split, we define the space-time distribution of mass/energy in this multiverse as the weighed (Born) sum of the distributions of the branches. So, each mass in each branch doesn't change; only its contribution to the corresponding "multiverse-total" mass is weighed. What is the point of a multiverse-total mass? I suppose it is intended as the source of gravitational field for any observer outside the Schroedinger-box in which the split is contained (assuming a separate, isolated, contained environment inside the box). To make it more concrete, consider a double-slit interference experiment, using one electron at a time. Instead of a screen there are many tiny pockets to capture the electron. Outside the box, there are many ultra-sensitive gravitational detectors, aiming to locate the electron in a pocket. But if the gravitational field of the electron, outside the box, is the weighed sum of all branches (one for each pocket), then the detectors will be unable to locate the electron. The gravitational measurements will indicate, instead of a single pocket, the interference pattern (which we would expect from a large number of electrons). So the gravitational measurements will produce something like an X-ray picture of a wavefunction, without destroying it. I find this queer, but here I quit for the night, waiting for any other opinions on this issue. George K. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/18abb32e-c247-49b0-9d73-0597261fa835n%40googlegroups.com.