A Brief History of Ideas About the Universe

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Christianity, Jews and Muslims believe that the Universe was made by God in six days. Most religions give some sort of deity the credit for the creation of the Universe. From Greek times until the middle of the sixteenth century is was also believed that the Earth was at the centre of the Solar System and Universe and both circled the Earth.

It was not until science began to be based on observation that this point of view was challenged in Europe. In 1543 a polish monk called Copernicus suggested a view view of the Solar System and put forward three laws of the motion of the planets. He suggested that all the planets moved about the Sun, basing his suggestion on years of observations.

In 1610, Galileo built the first telescope and saw the moons of Jupiter for the first. Time. The moons, orbiting Jupiter, were in direct contradiction to the teachings of the roman catholic church at the time, that all heavenly bodies orbited the Sun.

In 1687 Isaac Newton published his theory of gravity and laws of motion. These explained Copernicus laws in a theoretical way, and explained and predicted much else, later observed. Cosmology was now firmly on a scientific basis. Still though it was assumed that the Universe was eternal and unchanging, having been so created by God. God have given all the particles in the Universe motion at the creation, and now they moved according to Newton's laws. This was called the clockwork model of the universe.

In 1785 William Hershcel and his sister estimated the number of stars in the Milky Way and suggested the Milky Way was only one of many galaxies.

In 1915, Albert Einstein published his General Theory of Relativity. This predictd the Universe be expanding. In 1929, the expanding Universe was confirmed by Edwin Hubble, who measured their redshifts – corresponding to the speed at which galaxies are moving away from us – and compared these with their distances.

In 1964, the cosmic microwave background radiation was discovered. This is essentially an echo of the Big Bang, the moment of creation of the Universe, and virtually disproved the other main cosmological theory – the Steady State Theory, that though the Universe was expanding, matter was being created all the time to fill the gaps as the Universe expanded.

The Universe, it is supposed, will at some point in the future undergo a Big Crunch, collapsing to a point, reversing the Big Bang, or continue to expand forever. Lately evidence has emerged to suggest the latter. The expansing of the Universe appears to be increasing in speed. There will be no Big Crunch.