Physics is an observational science and therefore we must be careful to base our theoretical models directly on observations and not allow the members of our community to ignore them when submitting their theories. For example, many feel the most reliable way to determine the age of the universe is by measuring its expansion rate … Read more
One of the biggest problems is cosmology is accurately determining how far distance objects are away from us. In 1998 researchers discovered the repulsive side of gravity when they discovered a discrepancy in apparent brightness of light from type 1A supernovae, which exploded billions of years ago suggested that it had traveled a greater distance … Read more
Physics is an observational science and therefore we must be careful to base our theoretical models on those observations and make sure the theoretical predictions we make using them conform to them. For example, the “Big Bang” the most widely accepted theoretical model of the universe’s beginning assumes it was an extremely hot dense environment … Read more
Is it an intrinsic property of space that cause velocities to make sense only by saying that this is moving with respect to something while accelerations or changes in velocity don’t require comparisons to give them meaning? Newton came to conclusion it was based an experiment involving a bucket of water. Greene, Brian describes his … Read more
A few years after Albert Einstein unified space and time in his (and by now very well tested!) Theory of General Relativity he applied it to the entire universe and found something remarkable. The theory predicts that the whole universe is either expanding or contracting. Later in 1929 the astronomer Edwin Hubble measured the velocities … Read more