We discuss issues related with the cosmological constant problem in the light of recent observations which tend to indicate that the expansion of the universe is presently undergoing an acceleration. Models of fundamental physics which address these issues are discussed.

Jihn E. Kim Department of Physics and Astronomy and Center for Theoretical Physics, Seoul National University, Seoul 151-747, Korea DOI: http://dx.doi.org/10.3204/DESY-PROC-2010-03/kim jihn After showing the axion couplings, I review the Hawking type solution of the cosmological constant problem, present a (probably) correct way to calculate the probability amplitude, and show that the Kim-Kyae...

The cosmological constant is an unexplained until now phenomena of nature that requires an explanation through string effects. The apparent discrepancy between theory and experiment is enourmous and has already been explained several times by the author including mechanisms. In this work the string theory theory of abolished string modes is documented and given perturbatively to all loop orders...

Contrary to popular mythology, Einstein did not invent the cosmological constant just in order construct his model universe. He discussed it earlier in “The Foundations of General Relativity”in connection with the proper structure of the source-free field equations. There he dismissed it as arbitrary and unnecessary. It was later that he found its inclusion to be essential to the construction o...

When the cosmological constant of spacetime is derived from the 5D inducedmatter theory of gravity, we show that a simple gauge transformation changes it to a variable measure of the vacuum which is infinite at the big bang and decays to an astrophysically acceptable value at late epochs. We outline implications of this for cosmology and galaxy formation. PACS numbers: 04.20.Cv, 04.50.+h, 98.62...