Beyond the Standard Model - the Variation of Fundamental Constants in Space-Time

Peter Schwerdtfeger
Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland, New Zealand

Vendredi 28 Octobre 2022, 11H00
Bibiothèque du LCT, Couloir 12-13, 4^ème étage, Campus Pierre et Marie Curie

Fundamental constants like the speed of light c, the Planck constant h or the gravitational constant G play defining roles in physics and chemistry. Modern theories attempting to unify all four fundamental forces of nature suggest that all fundamental constants may vary in space and time. A small deviation from these constants would result in a completely different universe not able to sustain life. The weak anthropic principle by Brendon Carter states that "we must be prepared to take account of the fact that our location in the universe is necessarily privileged to the extent of being compatible with our existence as observers."
The search for small variations currently constitutes one of the most exciting areas of modern physics as it goes beyond the standard model in particle physics. In fact, this area of research is motivated by new theories unifying gravity with the other three fundamental interactions, as well as by a number of cosmological models. From atomic clock experiments we already know that the variation of the fine structure constant Δα/α is less than ˜10^-17 per year, and the variation in the electron to proton mass ratio Δμ/μ (μ=m_e/m_p) is similarly small with less than ˜10^-15 per year. Quasar and Big Bang nucleosynthesis data gave hints for non-zero variations, which, however, have not been confirmed yet. For further progress in this area, it is important to find enhanced effects in atoms or molecules for the variation of fundamental constants.