Theory HEP Seminar

Why are the effective equations of loop quantum cosmology so accurate?

Edward Wilson-Ewing

Louisiana State University

We point out that the Heisenberg uncertainty relations vanish for non-compact spaces in loop quantum cosmology. As a consequence, for sharply peaked states quantum fluctuations in the scale factor never become important, even near the bounce point. This shows why quantum back-reaction effects remain negligible and explains the surprising accuracy of the effective equations in describing the dynamics of sharply peaked wave packets. This also underlines the fact that minisuperspace models —where it is global variables that are quantized— do not capture the local quantum fluctuations of the geometry.