Suppose we managed to arrange a causality-violating transmission of data with hypothetical “superluminal cables” (SLC; see both links for respective descriptions) and expect, similarly to ideas popularized by David Deutsch, that it might result in communication from one “alternative reality” to another. Exact schemes may vary from the simple “send a word from a future and receive (the same or another) word in a past”.
Main questions are:
- How should we analyse the data received to investigate possible differences between quantum interpretations?
- How could experimenters reliably verify “several alternative realities” condition, debunking possible alternative explanations?
Any analysis of the setting leading to non-obvious implications, even speculative, can be considered a satisfactory answer. Ī only ask to describe carefully conditions of an experiment, see the two bottommost questions below.
Supplementary questions (Ī desire to consider them to some extent, but not require it for a satisfactory answer) are:
- How could this condition (even short-lived) be exploited?
- Would transmission of quantum information over an SLC offer some gains over transmission of purely classical information?
- Should a difference between physical principles behind our SLCs (such as General Relativity vs a hypothetical anomalous Lorentz symmetry-violating solid) influence quantum aspects of the experiment??