The use of precise spectroscopy for detailed studies of star forming regions and fundamental priperties of the Universe

Summary form only given. Due to significant increase of the accuracy of measured laboratory frequencies of interstellar molecular lines and their hyperfine splitting [1-3], tremendous increase of receivers sensitivity and frequency resolution of digital spectrometers, modern radioastronomical observations allow us to measure turbulence and systematic velocity gradients in star forming regions with precision about 1 m/s. The reported results show a search for and detailed multiline studies of collapsing cores in several dozens of dark clouds performed with MPIfR-lOOm, NRO45m, IRAM-30m, OSO-20m, SETS-15m and CSO-10.4m telescopes. It is shown that by using developed by us codes for MEM deconvolution [4] we increase significantly effective spatial resolution. Due to high spatial and frequency resolution differential cloud rotation and strong molecular depletion in central parts of the objects was revealed in a set of star forming regions. From comparison of precise laboratory and interstellar line frequencies a strong upper limit is obtained on variations of the electron to proton mass ratio [5]. It is shown how the detailed analysis of spectra, obtained at very high accuracy, makes it possible to draw the far reaching conclusions relative to the physical properties of our Universe.