1997/11/27 by John D. Barrow, Barrow, John D.
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #astro-ph #gr-qc
paper · pdf · doi:10.48550/arxiv.gr-qc/9711084
37 pages, Tex file, no figures. Lecture notes. Erice Summer School 'Current Topics in Astrofundamental Physics' 4-15 September 1997
arxiv created 1997/11/27 · arxiv updated 2009/11/30
We review recent progress in the study of varying constants and attempts to explain the observed values of the fundamental physical constants. We describe the variation of G in Newtonian and relativistic scalar-tensor gravity theories. We highlight the behaviour of the isotropic Friedmann solutions and consider some striking features of primordial black hole formation and evaporation if G varies. We discuss attempts to explain the values of the constants and show how we can incorporate the simultaneou s variations of several 'constants' exactly by using higher-dimensional unified theories. Finally, we describe some new observational limits on possible space or time variations of the fine structure constant.