Monday, January 25, 2010

The Reason Why the Earth is at the Center of the Universe

I'm reading Galileo at Work: His Scientific Biography by Stillman Drake. Galileo had literary interests as well as scientific. When he was younger (before he had even adopted the Copernican system) he was invited to lecture on Dante's Inferno. "Galileo expounded on God's reasons for having placed [the earth] at the center of the universe --- namely, to have it as far as possible from the sight of the blessed residents of Heaven, least they be offended by its grossness."
'In the midway of this our mortal life, I found me in a gloomy wood, astray'

Alternatives to dark matter

Alternatives to dark matter: Modified gravity as an alternative to dark matter by Jacob D. Bekenstein.
The premier alternative to the dark matter paradigm is modified gravity. Following an introduction to the relevant phenomenology of galaxies, I review the MOND paradigm, an effective summary of the observations which any theory must reproduce. A simple nonlinear modified gravity theory does justice to MOND at the nonrelativistic level, but cannot be elevated to the relativistic level in a unique way. I go in detail into the covariant tensor-vector-theory (TeVeS) which not only recovers MOND but can also deal in detail with gravitational lensing and cosmology. Problems with MOND and TeVeS at the level of clusters of galaxies are given attention. I also summarize the status of TeVeS cosmology

The Crab Canon by J.S.Bach

There's a discusion of the video here: This Week's Finds in Mathematical Physics (Week 291).