|Fields||Mathematical Physics, Physics|
|Institutions||University of Vienna|
|Alma mater||Göttingen University|
|Doctoral advisor||Hans-Jürgen Borchers|
|Known for||Quantum Field Theory
|Notable awards||Levi Conant prize|
Jakob Yngvason (born 1945) is an Icelandic/Austrian physicist. He is professor of mathematical physics at the University of Vienna and Deputy Director of the Erwin Schrödinger International Institute for Mathematical Physics (ESI) in Vienna. He has made important contributions to local quantum field theory, thermodynamics, and the quantum theory of many-body systems, in particular cold atomic gases and Bose–Einstein condensation. He is co-author, together with Elliott H. Lieb, Jan Philip Solovej and Robert Seiringer, of a monograph on Bose gases 
After graduating from high school in 1964 in Reykjavík, Yngvason studied physics at Göttingen University, obtaining his Diploma in physics in 1969 and dr.rer.nat. in 1973. His thesis advisor was Hans-Jürgen Borchers. Yngvason was assistant professor at the University of Göttingen 1973–1978, 1978–1985 research scientist at the Science Institute of the University of Iceland and 1985–1996 professor of theoretical physics at the University of Iceland. Since 1996 he has been professor of mathematical physics at the University of Vienna. He was Vice-President of the International Association of Mathematical Physics 2000–2005 and Editor-in-Chief of Reviews in Mathematical Physics 2006-2010. He is a member of the Societas Scientiarum Islandica and corresponding member of the Academy of Sciences in Göttingen and the Royal Danish Academy of Science and Letters, Copenhagen. For his work on Thermodynamics  he received, together with Lieb, the Levi Conant Prize of the American Mathematical Society in 2002. In 2004 he received the Erwin Schrödinger Prize of the Austrian Academy of Sciences. He is married to Guðrún Kvaran, Professor of Lexicography at the University of Iceland; they have two children.
- Lieb, Elliott H.; Seiringer, Robert; Solovej, Jan Philip; Yngvason, Jakob: "The mathematics of the Bose gas and its condensation". Oberwolfach Seminars, 34. Birkhauser Verlag, Basel, 2005. viii+203 pp. ISBN 978-3-7643-7336-8; 3-7643-7336-9.
- Lieb, Elliott H., Yngvason, Jakob: "The physics and mathematics of the second law of thermodynamics". Physics Reports 310, 1–96 (1999) .
- "2002 Conant Prize". Notices of the AMS, "'49"', 481–482 (2002)
- Guðrún Kvaran (December 2010). "Curriculum vitæ". Retrieved 2011-01-30.