Question

​what is meant by massive vector boson

Answer 1

Dear Student,
In particle physics a vector boson has spin 1.Vector bosons are the elementary particles which are the force carriers of fundamental interactions. Massive vector bosons means the boson which have mass like W⁺,W^- and Z⁰ weak interaction bosons. The only known mass less boson with spin 1 particle is Photon.
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