Massless Objects

[raina_bandekar_1G]

I know the de Broglie equation is used for objects with mass and the einstein equation is used for massless objects such as photons, however, I was wondering if there are any other types of "massless" objects that we can use the einstein equation for.

[Raquel]

I searched it up, and though I haven't heard of anything else used for Einstein's E=hf, for the other equation, p=h/λ, which relates to momentum, can be used for electrons, and though they aren't massless, they still work for this equation!