15 MAR 2013 by ideonexus

 Einstein's "Biggest Blunder"

For much of the modern era, scientists followed Nicolaus Copernicus, Galileo Galilei, and Isaac Newton in believing the cosmos to be eternal and unchanging. But in 1917, when Albert Einstein applied his theory of relativity to space-time as a whole, his equations implied that the universe could not be static; it must be either expanding or contracting. This struck Einstein as grotesque, so he added to his theory a fiddle factor called the "cosmological constant" that eliminated the implicatio...
 1  1  notes

The story of how Einstein's belief in a static Universe prompted him to introduce a fudge-factor in his Theory of Relativity, the Cosmological Constant.

18 JAN 2013 by ideonexus

 The Story of How the Universe's Size was Determined

It was into this fiery climate of the 1920s that the Protestant-raised Hubble, adorned with the cape, cane, and British accent he had adopted while at Oxford, returned after the war. He arrived at the Carnegie Institution of Washington-funded Mount Wilson Observatory outside Pasadena, California, insisting on being called "Major Hubble."^'' Looking through the great Hooker telescope—at one hundred and one inches in diameter and weighing more than one hundred tons it was by far the largest a...
  1  notes

Includes a cautionary tale of Shapely, who helped prove the Sun was not the center of the Universe, but who thought the Milky Way was all the Universe there was without empirical data.