Asked by: Terry Stanton, by email
According to Einstein’s General Relativity, which is our best current description of space and time, the only place where time – and also space – ends is in a so-called singularity. This involves gravitational forces becoming so intense that space and time lose all meaning.

While this is a theoretical possibility if the Universe collapses into a ‘Big Crunch’, observations suggest the current cosmic expansion will continue indefinitely.
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