After a star lives and dies, I assume virtually all of it's mass would be photons. If enough stars have already lived and died, couldn't there be enough photon energy out there to account for all the ...
Dark matter does have gravitational mass as we know from its discovery. Does it have inertial mass?
In my understanding, there exists a critical mass for which a star needs to be in order for it to collapse into a black hole. This also applies to a certain critical density of gas in order for stars ...
Do we consider the amount of matter in the universe to be "infinite"? Or do we have an idea about "how much" there is?
Inertial mass: determined from Newton's f = ma Gravitational mass: determined via Newton's law of gravity Baryonic mass: sum of mass of all baryons. Which ones ...