5 ms·

>>Flying through a galaxy at 0.999c is identical to "sitting still" while a galaxy flies by at 0.999c.spaceship. You're right if you were sitting in a train an

>>Flying through a galaxy at 0.999c is identical to "sitting still" while a galaxy flies by at 0.999c.spaceship. You're right if you were sitting in a train and watched the station go by, but not at .999c. You're ignoring relativistic mass. Unlike General Relativity where we were able to measure the effects of sun's gravity against the position of emitted light from the stars, The truth is we have no empirical evidence of the effects on solid objects (not single accelerated particles) approaching C.

Strilanc 14y ago
Read the Wikipedia article on mass in special relativity (http://en.wikipedia.org/wiki/Mass_in_special_relativity http://en.wikipedia.org/wiki/Mass_in_special_relativity). The summary of the article mentions that, in the mass' frame of reference, relativistic mass is the same as rest mass: > As seen from the center of momentum frame, the relativistic mass is also the invariant [rest] mass [...] Actually, the whole idea of relativistic mass is misleading to intuition. It makes more sense to think of relativistic energy. This is mentioned near the end of the article: > Many contemporary authors such as Taylor and Wheeler avoid using the concept of relativistic mass altogether: > > > "The concept of "relativistic mass" is subject to misunderstanding. That's why we don't use it. First, it applies the name mass - belonging to the magnitude of a 4-vector - to a very different concept, the time component of a 4-vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself."[6] Remember: the laws of physics are invariant with respect to absolute velocity. If you add 5 m/s along some direction to all velocities, all the same interactions will occur. Relativity does not break this invariant.

Strilanc 14y ago

Read the Wikipedia article on mass in special relativity (http://en.wikipedia.org/wiki/Mass_in_special_relativity http://en.wikipedia.org/wiki/Mass_in_special_relativity). The summary of the article mentions that, in the mass' frame of reference, relativistic mass is the same as rest mass: > As seen from the center of momentum frame, the relativistic mass is also the invariant [rest] mass [...] Actually, the whole idea of relativistic mass is misleading to intuition. It makes more sense to think of relativistic energy. This is mentioned near the end of the article: > Many contemporary authors such as Taylor and Wheeler avoid using the concept of relativistic mass altogether: > > > "The concept of "relativistic mass" is subject to misunderstanding. That's why we don't use it. First, it applies the name mass - belonging to the magnitude of a 4-vector - to a very different concept, the time component of a 4-vector. Second, it makes increase of energy of an object with velocity or momentum appear to be connected with some change in internal structure of the object. In reality, the increase of energy with velocity originates not in the object but in the geometric properties of spacetime itself."[6] Remember: the laws of physics are invariant with respect to absolute velocity. If you add 5 m/s along some direction to all velocities, all the same interactions will occur. Relativity does not break this invariant.