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PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE

PIRSA:14030114  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Are superselection rules fundamental?
Speaker(s): Robert Spekkens
Abstract: Superselection rules in quantum theory assert the impossibility of preparing coherent superpositions of certain conserved quantities. For instance, it is commonly presumed that there is a superselection rule for charge and for baryon number, as well as a "univalence superselection rule" forbidding a coherent superposition of a fermion and a boson. I will show how many superselection rules can be effectively lifted using a reference frame for the variable that is conjugate to the conserved quantity. I will also discuss subtleties related to the univalence superselection rule.
Date: 14/03/2014 - 10:00 am
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