In 1986 Prof Schutz, from the School of Physics and Astronomy, showed how gravitational waves can be used to measure the
cosmic expansion rate.
Prof Schutz explained in his 1986 paper how gravitational waves could be used to measure the
cosmic expansion rate.
That's why, when he learned of
cosmic expansion, Einstein could forgo the need for lambda and describe the expansion with the original equations--and why, when the antigravity effect of dark energy was discovered, lambda went back in.
The anisotropy in the DE pressure along direction x is almost unaffected by
cosmic expansion for all three considered viscous coefficient values.
What we are seeing are the deviations from
cosmic expansion caused by the interactions of local sources of gravity.
Science writers and astronomy scholars provide an introduction to astronomy and its discoveries about space, time, and the physics of the cosmos, detailing the history of the subject from ancient speculations about the nature of the universe, to the Copernican revolution, to the rise of astrophysics, to the theory of relativity, to theories about dark energy and
cosmic expansion, including technological breakthroughs like GalileoAEs telescope; the first person on the moon; discoveries about gravity, planets, nebulae, stars, the Big Bang, and black holes; and the contributions of key astronomers like Copernicus, Tycho Brahe, and Edwin Hubble.
The previous two models that tried to explain this were both based on the simplified 100-year-old
cosmic expansion law - Friedmann's equation.
It underpinned Edwin Hubble's law on
cosmic expansion and led to discoveries about the shape of the Milky Way, our solar system's place far from the galactic center and the existence of other galaxies.
The theory of
cosmic expansion, originally proposed by Georges Lemaitre in 1931, offers the best explanation for observational data of our universe, starting with Edwin Hubble in 1929 to the present.
Scientists are now grappling with other mysteries such as understanding the nature of dark matter, which accounts for more than a quarter of the universe, and dark energy, which is believed to be the driver of
cosmic expansion.
The fact that our universe is expanding in all directions could be a sign simply of
cosmic expansion, rather than as the origin of the universe itself, the researchers suggest.