12-16 October 2015
Hungarian Academy of Sciences
Europe/Budapest timezone

Precision measurements on H2 in search for new physics

Oct 12, 2015, 3:15 PM
Kis terem (Small conference room) (Hungarian Academy of Sciences)

Kis terem (Small conference room)

Hungarian Academy of Sciences

1051 Budapest, Széchenyi tér 9.


Wim Ubachs (VU University Amsterdam)


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.

Primary author

Wim Ubachs (VU University Amsterdam)

Presentation materials