|The Hydrogen Lyman-alpha line, strongest recombination line of the most
abundant atom in the Universe, is observed in a broad range of astrophysical contexts. However, it's
resonant nature complicates the interpretation of most Lyman-alpha observations. Radiation transfer
studies can help understanding the complicated alteration of the line along its travel to the observer.
I will present concrete effects of radiation transfer in simple geometrical configurations,
and in more realistic simulations of galaxy formation and Lyman-alpha blobs.
I will describe implications of my work for the interpretation of
Lyman-alpha properties of galaxies, in the local universe and at high redshift.