From https://arxiv.org/pdf/1712.03079

Suppose some future technology enables the same consciously experienced human life to be repeated, identically or nearly so, N times, in series or in parallel. Is this roughly N times as valuable as enabling the same life once, because each life has value and values are additive? Or is it of roughly equal value as enabling the life once, because only one life is enabled, albeit in a physically unusual way? Does it matter whether the lives are contemporaneous or successive? We argue that these questions highlight a hitherto neglected facet of population ethics that may become relevant in the not necessarily far distant future.

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the intuition behind replication futility is that, having written Alice’s life into the universe once, we add nothing to the total value of the universe (integrated over space and time) by doing so again. In particular, we add no value for Alice by repeating her emulation, even though each emulation of Alice has the sense of appreciating their life.

I remember reading something similar on this a while ago, possibly on this forum, but I can't find anything at the moment, does anyone remember any other papers/posts on the topic?

Cross-posted from the EA Forum