1. Gravitational lenses measure universe expansion  Phys.org
  2. Gravitational lenses could hold the key to better estimates of the expansion of the universe  Phys.org
  3. View Full coverage on Google News
It's one of the big cosmology debates: The universe is expanding, but how fast exactly? Two available measurements yield different results. Leiden physicist David Harvey adapted an independent third measurement ...

Gravitational lenses measure universe expansion

The universe is expanding but astrophysicists aren't sure exactly how fast that expansion is happening—not because there aren't answers, but rather because the answers they could give don't agree.

Gravitational lenses could hold the key to better estimates of the expansion of the universe