What is "massless"

Usage examples of "massless".

This is how, we recall, unwrapped strings can yield the zero-mass photon, graviton, and the other massless or near-massless particles, for example.

Only drunks would start by postulating an unfueled, massless wagon that could keep up with the wind.

Every second the Earth is visited by 10,000 trillion trillion tiny, all but massless neutrinos (mostly shot out by the nuclear broilings of the Sun), and virtually all of them pass right through the planet and everything that is on it, including you and me, as if it weren’t there.

All that existed before then were electrons (and their positively charged forms, positrons), neutrons, protons, neutrinos (a chargeless particle, until recently assumed to be massless but now thought to possess a tiny mass), and radiation.

A massless anomaly in the vacuum, small as a subatomic particle, it would be almost impossible to find.