Klaus Liegener, LSU
Title: New Loop Quantum Cosmology modifications from Symplectic Structures
PDFof the talk (2M)
Audio+Slidesof the talk (38M)
Loop quantum gravity is based on a new set of variables for describing general relativity that were introduced by Abhay Ashtekar. These variables have a certain amount of redundancy, known as a gauge symmetry.
Loop quantum cosmology is an approximation to loop quantum gravity that attempts to model cosmologies by following only a very limited number of degrees of freedom. A current topic of great interest is to understand how and if this approximation captures behaviors of the full theory. This talk concentrated on the role the redundancies in the variables Ashtekar introduced play in the construction of loop quantum cosmologies. It proposes to use certain variables that better behave under the presence of these redundancies and draws implications for the dynamics of the resulting theory. In particular it implies, as is common in loop quantum cosmology, that the Big Bang at the beginning of the universe is replaced by a "bounce" from a previous universe. However, the dynamics of the current model implies the bounce is asymmetrical, the universe before and after it do not look the same. This had been encountered in some previous proposals for loop quantum cosmologies, but not in all of them.
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