PIRSA:14110133  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Modified Gravity (MOG) and Dark Matter: Can We Detect Dark Matter in the Present Universe?
Speaker(s): John Moffat

A modified gravity (MOG) theory is explored that can explain current observational data in the present universe without detectable dark matter. This data includes galaxy rotation curves, cluster dynamics, gravitational lensing, globular clusters, the Bullet Cluster and solar system experiments. A vector field in the MOG action is a hidden, dark and massive photon that acts as a collisionless particle in the early universe and explains structure growth. The vector field evolves to an ultralight hidden photon in the present universe after the formation of stars and galaxies, and it cannot play the role of detectable dark matter. The theory successfully describes the CMB data. The matter power spectrum is fitted without dark matter and can distinguish between modified gravity and dark matter scenarios in the present universe.

Date: 20/11/2014 - 11:00 am
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