Barak Hirshberg was born and raised in Jerusalem and attended Boyer High School; his interest in science began there under the influence of his mathematics teacher.  After high school, he postponed his military service for three years in order to do a BSc in chemistry at the Hebrew University, as a member of the Amirim Natural Sciences Excellence Program. During this period he was an undergraduate research assistant in the lab of Professor R. Benny Gerber, where he worked on his BSc thesis on the electronic structure and dynamics of all-nitrogen molecules.

After graduating magna cum laude, Barak joined the IDF for six years as a theoretical chemist in RAFAEL Ltd. At the same time he studied for his MSc in the group of Prof. Gerber, later transferring to the direct PhD program. Barak has published six papers in international journals, as the leading author of three of them. His most significant contribution is a paper which predicts the existence of a new phase of solid nitrogen, published in 2014 in Nature Chemistry. This work brought him the Lise Meitner Prize for an outstanding study in computational quantum chemistry.

One of the main topics addressed in the Gerber Group is the electronic structure and chemical dynamics of atmospherically relevant molecules and processes. Currently, Barak studies the reaction between hot CO₂ molecules impacting on water clusters and surfaces, using ab initio molecular dynamics simulations. This reaction is important for the formation of carbonic acid in the oceans, which might lead to ocean acidification.