According to legend, when Damocles declared that his king, Dionysius, must have a posh and easy life, Dionysius offered to trade places with Damocles. There was only one catch. Dionysius decreed that a sword be suspended over the throne by a single horse hair, so that Damocles would always know the peril of being king. Since then the Sword of Damocles has come to represent a threat of doom that could strike without warning.
Let’s now go to quantum systems. A long-known property of quantum mechanics, that quantum systems don’t always have to settle in their most stable configuration. They can instead find themselves in a locally stable state (known as a metastable state).
Could we live in a universe which is stable, but just LOCALLY stable? scientists wonder (1)
But why should we care?
Is there ANYTHING which is eternally “stable”?
What does that even mean?!?
And this is the best proof that nothing changes at all…
You are here.
And you will be here for ever.
And yet always the same…