The Three-Box "Paradox" and Other Reasons to Reject the Counterfactual Usage of the ABL Rule

Abstract

An apparent paradox proposed by Aharonov and Vaidman in which a single particle can be found with certainty in two (or more) boxes is analyzed by way of a simple thought experiment. It is found that the apparent paradox arises from an invalid counterfactual usage of the Aharonov-Bergmann-Lebowitz (ABL) rule, and effectively attributes conflicting properties not to the same particle but to different particles. A connection is made between the present analysis and the consistent histories formulation of Griffiths. Finally, a critique is given of some recent counterarguments by Vaidman against the rejection of the counterfactual usage of the ABL rule.