Talk detail

Participant	Ubachs, Wim
Institution	VU University Amsterdam, Dept. of Physics - De Boelelaan 1081 - Amsterdam - - Netherland

Session	EG2	Accepted		Order	Time
Talk	Oral abstract	Title	Search for a drifting proton-electron mass ratio on a cosmologicala time scale
Co-authors
Abstract	Accurate measurements of molecular line spectra in the early Universe, compared to laboratory measurements of the same lines can reveal possible drifts in the value of a dimensionless fundamental constant of nature: the proton-electron mass ratio (mu). We will report on observations of molecular hydrogen lines at redshifts z>2 that have yielded constraints on a relative variation of mu at the level of 10^(-5). Recently we have discovered that spectral lines of the methanol molecule at microwave frequencies have much larger sensitivities for varying constant, up to a thousand times more sensitive than H2. We will present data on a comprehensive study of methanol in PKS-1830 by radio-astronomy revealing much tighter constraints on a varying mu.