The primary objective of the study is the investigation of the physical properties and chemical composition of matter at different cosmological epochs. The investigation is based on high-resolution spectral observations of hydrogen and metal (C IV, Si IV, O VI and others) absorption-line profiles and advanced models of the radiative transfer in random media.
A statistical analysis of space-time distributions of C IV and Mg II absorption-line systems observed in QSO spectra within the cosmological redshift interval z=0.2-3.2 is performed. The results obtained give an evidence of possible existence of Global Large-Scale Structure of space-time distribution of matter in the Universe.
We have analyzed the spectrum of the quasar PKS 1232+082 obtained by Petitjean et al. (2000). HD molecular lines are identified in an absorption system at the redshift z = 2.3377.