[1] He is known for the development of the Lindhard theory, that describes the behaviour of metals under the influence of electromagnetic fields, named in his honour.
[1] Jens' father was a professor at University of Copenhagen Faculty of Life Sciences but died young in 1928.
[1] There, in 1954, he published the first description of the dielectric function of metals in the linear response regime, today known as Lindhard theory.
[2][1] There Lindhard, Morten Scharff and H. E. Schiøt developed what is now known as the LSS theory [de] (carrying their initials), which describes the penetration of low-energy ions.
[2][1][5] Lindhard moved to Aarhus University in 1957 in collaboration with experimentalist Karl Ove Nielsen, where he created and led a research group to study the penetration of charged particles in crystal lattices.