Speaker
Wim Ubachs
(VU University Amsterdam)
Description
Molecular hydrogen is the smallest neutral molecule and the most abundant molecular species in the Universe. High-resolution spectroscopic studies of this benchmark system can serve as a test for various directions in the exploration of new physics. Several of those have been pursued:
- The search for a variation of the proton-electron mass ratio in earlier phases of the Universe; this is done via the analysis of absorption systems in the line-of-sight of quasars.
- The search for a possible dependence of the proton electron mass ratio depending on environmental conditions, such as the local gravitational field; this is done via the analysis of absorption spectra of the photosphere of white dwarf stars.
- The search for possible fifth forces between hadrons; this is done via precision measurement of the dissociation limit of the H2 molecule and a measurement of the vibrational ground tone splitting.
- The same experimental data can also be employed to detect possible extra dimensions beyond the known 3+1 space-time dimensionality.
All of these directions will be highlighted and the possibility for improvements and tighter constraints discussed.
Author
Wim Ubachs
(VU University Amsterdam)
