4 ms·

Why would it?

• floxy 4y ago
  I thought dark energy was the reason the non-gravitational-bound galaxies are accelerating away from each other? If they are accelerating, that would be a change in velocity, which seems like a change in momentum. ?
  • rhn_mk1 4y ago
    The name "acceleration" is just as misleading as "expanding" here, but maybe useful. Our galaxy is non-gravitationally-bound to a lot of other galaxies, and we "accelerate" away from them. Yet we don't really feel that. We also obviously can't accelerate away from all of them, when they are in random directions. That's because the "acceleration" describes the change of distance, without changing position. Without changing position, there's no change of momentum. That "acceleration" is a consequence of the expansion/stretching described in the article.
    • floxy 4y ago
      Why is it called dark energy if energy isn't changing?