2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90134We study the class of protocols for weak quantum coin flipping introduced by Spekkens and Rudolph (quant-ph/0202118). We show that, for any protocol in this class, one party can win the coin flip with probability at least $1/\sqrt{2}$.6 pagesQuantum PhysicsCryptography and Securitytext