|MadSci Network: Physics|
Any particle-antiparticle pair can be generated from "nothing" (the vacuum) and in fact they are. Their lifetime depends on the mass (the energy) of those particles, the heavier the particles are the shorter is the lifetime, because they are generated due to the Energy-Time uncertainty. This relation reads
(dE) (dt) ~ hwhere dE is the energy uncertainty (the energy of the created particle-antiparticle pair) and dt is the time uncertainty (the lifetime of the respective particles), h is the so-called Planck constant. This is true for all types of particles, also for photons. In case of photons the frequency is proportional to its energy, E = h f, where f denotes the frequency.
By the way, a photon is its own antiparticle.
I hope this helps,
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