Cosmological constant abandoned
Main article: Cosmological constant
After Hubble's discovery was published, Albert Einstein abandoned his work on the cosmological constant, which he had designed to modify his equations of general relativity to allow them to produce a static solution, which he thought was the correct state of the universe
. The Einstein equations in their simplest form model generally either an expanding or contracting universe, so Einstein's cosmological constant was artificially created to counter the expansion or contraction to get a perfect static and flat universe. After Hubble's discovery that the universe was, in fact, expanding, Einstein called his faulty assumption that the universe is static his "biggest mistake". On its own, general relativity could predict the expansion of the universe, which (through observations such as the bending of light by large masses, or the precession of the orbit of Mercury) could be experimentally observed and compared to his theoretical calculations using particular solutions of the equations he had originally formulated.
In 1931, Einstein made a trip to Mount Wilson
to thank Hubble for providing the observational basis for modern cosmology.
The cosmological constant has regained attention in recent decades as a hypothesis for dark energy
Einstein had a different theory until Hubble "Proved" him wrong through his observations. Again, we are in a cloud of dust that Hubble did not know about when he made his measurements. The equipment he used to do this is less accurate than what people have at home and this effectively ended the search for an answer. If Hubble was wrong, then it doesn't allow for Einstein work, his own WORDS. The bending of light that has been observed is better explained through atmospheric lensing.
Hubble was able to plot a trend line from the 46 galaxies he studied and obtain a value for the Hubble constant of 500 km/s/Mpc (much higher than the currently accepted value due to errors in his distance calibrations). (See cosmic distance ladder
This is so wrong it is terrible. It acts as if space is homogenous and it is in the article very clearly.
Idealized Hubble's law
The mathematical derivation of an idealized Hubble's law for a uniformly expanding universe is a fairly elementary theorem of geometry in 3-dimensional Cartesian
/Newtonian coordinate space, which, considered as a metric space
, is entirely homogeneous and isotropic
(properties do not vary with location or direction). Simply stated the theorem is this:
Any two points which are moving away from the origin, each along straight lines and with speed proportional to distance from the origin, will be moving away from each other with a speed proportional to their distance apart.
In fact this applies to non-Cartesian spaces as long as they are locally homogeneous and isotropic; specifically to the negatively and positively curved spaces frequently considered as cosmological models (see shape of the universe
An observation stemming from this theorem is that seeing objects recede from us on Earth is not an indication that Earth is near to a center from which the expansion is occurring, but rather that every
observer in an expanding universe will see objects receding from them.