Quantum Tunneling in the Everettian Multiverse

Quantum tunneling is analyzed within the Everettian interpretation, where decoherence generates distinct reflected and transmitted branches. The tunneling probability is obtained from relative branch weights via the Born rule without invoking collapse. Tunneling time \(τ_T \) is reformulated as the branching duration \(τ_T \sim N_B τ_B\), where\(\ N_B \) is the number of environmental degrees of freedom and \(τ_B\) is the decoherence time required to distinguish branches. Macroscopic tunneling in Josephson junctions is also analyzed.