Huw Price (Cambridge) gives a talk at the MCMP Colloquium titled "Retrocausality - What Would it Take?". Abstract: Some writers argue that retrocausality offers an attractive loophole in Bell's Theorem, allowing an explanation of EPR-Bell correlations without "spooky action-at-a-distance." This idea originated more than a decade before Bell's famous result, when de Broglie's student, Olivier Costa de Beauregard, first proposed that retrocausality plays a role in EPR contexts. The proposal is difficult to assess, because there has been little work on the general question of what a world with retrocausality would "look like" - what kinds of considerations, if any, would properly lead to the conclusion that we do live in such

a world. In this talk I discuss these general issues, with the aim of bringing the more specific question as to whether quantum theory implies retrocausality into sharper focus than has hitherto been possible.