Question

What does it mean for a graviton to have mass?

Answer 1

In the classical limit:

V(r)∝G1re−r/mV(r)∝G1re−r/m

so in the limit m→0m→0, V(r)→V(r)→ Newton.

Meanwhile, gravitons (like photons) are their own anti-particle, so their number isn't conserved.

Regarding a quantum field theory of massive gravitons: why not? The massless one doesn't work anyway.

Answer 2

The graviton is a hypothetical elementary particle that mediates the force of gravitation in the framework of quantum field theory.

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