The Metaphysical Mismatch in Modal Interpretations of Quantum Mechanics: Beyond Necessary Equivalence
M. Coelen
Abstract
The measurement problem is one of the major philosophical problems in the Philosophy of Quantum Mechanics. Modal Interpretations of Quantum Mechanics aim to overcome the measurement problem, however, not always without a hitch: other problems arise. That is, some Modal Interpretations claim that a property Q, considered in a subsystem , is a di erent property while considered in the composite physical system , this while both situations are empirically indistinguishable: a non-empirical mismatch ensues. The mismatch, that seems to manifest at the metaphysical level, implies that empirically equivalent propositions like \\the left-hand side of the table is green" (subsystem) and \\the table is green at the left-hand side" (composite system) are metaphysically di erent. Although such a conclusion is clearly at odds with our everyday idea of properties, in my thesis, I question why metaphysical equivalence should (directly) ensue from empirical equivalence. The goal is to provide an explanation why the mismatch can been seen as a correct representation. Furthermore, I question what is exactly ment by metaphysical. As it turns out, under certain circumstances, by using an injective non-surjective function f that sends ordered pairs of operators to quantitative properties, in all possible worlds, the mismatch appears to be a correct representation. Nevertheless, since there are good reasons to renounce the mismatch, I question the level of activity and I invoke a more ne-grained version of metaphysics, i.e hyperintensional metaphysics. A relation between two entities is considered as hyperintensional from the very moment the relation is more ne-grained than necessary equivalence: beyond necessary equivalence. Finally, I claim that the mismatch must be understood in terms of beyond necessary equivalence and should be seen as a correct representation of the relation between language and reality in all hyperintensional worlds.