3 ms·
It's neither massive nor massless object that follow geodesics, it's objects with energy (including the mc^2 kind).
by ars 6y ago
It's neither massive nor massless object that follow geodesics, it's objects with energy (including the mc^2 kind).
- nimish 6y agoYes, and "massive" and "massless" exhaustively covers both, with the special highlighting of massless particles which are further constrained to follow null geodesics. Massive particles don't have that limitation but they only travel time-like geodesics (as far as we know).
- ars 6y ago> with the special highlighting of massless particles which are further constrained to follow null geodesics. Only to an approximation. Photons generate gravitational fields, and the planets they travel near are attracted to the photons (not much obviously). (See: Kugelblitz) Gravity does not treat photons specially, the rules are the same as for other particles. For extra credit imagine a Kugelblitz traveling by at light speed - it's moving so fast, it doesn't have time to add any mass. Yet, mass transited inside the event horizon of this object.