The Long Earth: Multiverse Physics

About this video

The physics behind the multiverse.

Philosopher of physics David Wallace guides us the many-worlds interpretation of quantum mechanics and the mind-bending claims it makes about our reality.

First proposed by American physicist Hugh Everett – and described by Wallace as the "coolest interpretation of quantum mechanics" – the many-worlds theory implies that all possible alternative histories and futures are real. Each alternative represents an actual 'world' (or 'universe').

From Erwin Schrödinger’s famous feline thought experiment to thinking about different types of different worlds, Dr Wallace demonstrates how the many-worlds interpretation can be seen as "irresistibly correct" when applying the logic of best physics available to us today (or, as he puts it, "thinking hard enough about it").

Can cats really be in two places at once? And, if multiple worlds exist, why are we stuck in the one with all the bad weather?

Keep up if you can...

Introduced by Roger Highfield from the Science Museum Group.