What Happens to Ethics Under Many-Worlds?

The Many Hidden Worlds of Quantum Mechanics – Season 1

A theory in which every moral act entails an immoral one taking place in a branching universe is rife with ethical quandaries. Now, consider whether you could be moral in each of the universes of a Many-Worlds scenario. One stumbling block is imagining that the version of you that took a branching path is actually you. You may share a past, but the two of you are really different people.