Uroš Seljak
{{Short description|Slovenian cosmologist}}
{{Infobox scientist
| name = Uroš Seljak
| image = Uros Seljak.jpg
| caption = Uroš Seljak in 2011
| birth_name =
| birth_date = {{birth date and age|df=yes|1966|5|13}}
| birth_place =
| death_date =
| death_place =
| citizenship = Slovenian, United States
| occupation = {{unbulleted list|Professor in Physics and Astronomy Departments, UC Berkeley|Senior Faculty Scientist, LBNL Berkeley}}
| known_for = E and B-modes, CMBFAST code {{cite web |title=Overview of CMBFAST |url=https://lambda.gsfc.nasa.gov/toolbox/cmbfast_overview.html |publisher=NASA |access-date=September 15, 2023 }}
| awards = {{unbulleted list|Helen B. Warner Prize for Astronomy (2001)|Gruber Prize in Cosmology (2021)}}
| fields = {{unbulleted list|Cosmology|Theoretical and observational astrophysics|Statistical data analysis in astrophysics|Bayesian statistical methodology|Machine learning}}
| alma_mater = {{plainlist|University of Ljubljana, Slovenia (1989, 1991) *MIT (1995)}}
| thesis_title = Light propagation in a weakly perturbed expanding universe {{cite thesis |title=Light propagation in a weakly perturbed expanding universe |date=1995 |url=https://dspace.mit.edu/handle/1721.1/37767 |publisher=MIT |hdl=1721.1/37767 |access-date=September 18, 2023 |type=Thesis |last1=Seljak |first1=Uros̆ }}
| thesis_url =
| thesis_year = 1995
| doctoral_advisor = Edmund Bertschinger
}}
Uroš Seljak (born 13 May 1966 in Nova Gorica) is a Slovenian cosmologist and a professor of astronomy and physics at University of California, Berkeley.[https://physics.berkeley.edu/people/faculty/uros-seljak Faculty profile], UC Berkeley physics department, retrieved 27 March 2011. He is particularly well-known for his research in cosmology and approximate Bayesian statistical methods.
Biography
Seljak completed his secondary education at the Nova Gorica Grammar School and carried out his undergraduate studies at the University of Ljubljana, Slovenia. He graduated in 1989 and later received a Master's degree from the same institution in 1991. Seljak conducted his doctoral research at Massachusetts Institute of Technology and received his PhD in 1995.
After postdoctoral studies at the Center for Astrophysics {{!}} Harvard & Smithsonian, he held faculty positions at Princeton University, the International Centre for Theoretical Physics in Trieste, Italy, and the University of Zurich, before joining the UC Berkeley physics and astronomy departments in 2008. He holds a joint appointment with the Lawrence Berkeley National Laboratory.
Career
Seljak is a cosmologist who is particularly well-known for his research on cosmic microwave background radiation,{{Cite journal|last1=Seljak|first1=Uroš|last2=Zaldarriaga|first2=Matias|date=1996|title=A Line-of-Sight Integration Approach to Cosmic Microwave Background Anisotropies|journal=The Astrophysical Journal|volume=469|pages=437–444|doi=10.1086/177793|arxiv=astro-ph/9603033|bibcode=1996ApJ...469..437S|s2cid=3015599}}{{cite magazine|last=Sincell|first=Mark|title=A New Lens on Dark Matter|date=30 March 1999|url=http://focus.aps.org/story/v3/st19|magazine=Physical Review Focus|volume=3}}. galaxy clustering and weak gravitational lensing,{{citation|title=Galaxy Study Validates General Relativity on Cosmic Scale, Existence of Dark Matter|date=10 March 2010|url=https://www.sciencedaily.com/releases/2010/03/100310134152.htm|journal=Science Daily}}. and the implications of these observations for the large scale structure of the universe.{{citation|last=Becker|first=Markus|title=Raumzeit-Wellen provozieren Forscher|date=20 April 2005|url=http://www.spiegel.de/wissenschaft/weltall/0,1518,347742,00.html|journal=Spiegel|language=German}}.
In 1997, Seljak predicted the existence of B-modes in CMB polarization that are a tracer of primordial gravitational waves from inflation.{{Cite journal|last=Seljak|first=Uroš|date=10 June 1997|title=Measuring Polarization in the Cosmic Microwave Background|journal=The Astrophysical Journal|language=en|volume=482|issue=1|pages=6–16|doi=10.1086/304123|issn=0004-637X|arxiv=astro-ph/9608131|bibcode=1997ApJ...482....6S|s2cid=16825580}} Together with Matias Zaldarriaga, he developed the CMBFAST code for CMB Temperature, E and B-mode polarization, and for gravitational lensing effects on CMB.
In 2000, he developed the halo model for dark matter{{Cite journal|last1=Seljak|first1=Uroš|last2=Makarov|first2=Alexey|last3=McDonald|first3=Patrick|last4=Trac|first4=Hy|date=8 November 2006|title=Can Sterile Neutrinos Be the Dark Matter?|journal=Physical Review Letters|language=en|volume=97|issue=19|pages=191303|doi=10.1103/PhysRevLett.97.191303|pmid=17155611|arxiv=astro-ph/0602430|bibcode=2006PhRvL..97s1303S|s2cid=22565444|issn=0031-9007}}{{Cite journal|last1=Seljak|first1=Uroš|last2=Makarov|first2=Alexey|last3=McDonald|first3=Patrick|last4=Anderson|first4=Scott F.|last5=Bahcall|first5=Neta A.|last6=Brinkmann|first6=J.|last7=Burles|first7=Scott|last8=Cen|first8=Renyue|last9=Doi|first9=Mamoru|last10=Gunn|first10=James E.|last11=Ivezić|first11=Željko|date=20 May 2005|title=Cosmological parameter analysis including SDSS Ly α forest and galaxy bias: Constraints on the primordial spectrum of fluctuations, neutrino mass, and dark energy|journal=Physical Review D|language=en|volume=71|issue=10|pages=103515|doi=10.1103/PhysRevD.71.103515|arxiv=astro-ph/0407372|bibcode=2005PhRvD..71j3515S|s2cid=15237151|issn=1550-7998}} and galaxy clustering statistics.{{Cite journal|last=Seljak|first=Uroš|date=11 October 2000|title=Analytic model for galaxy and dark matter clustering|journal=Monthly Notices of the Royal Astronomical Society|language=en|volume=318|issue=1|pages=203–213|doi=10.1046/j.1365-8711.2000.03715.x|arxiv=astro-ph/0001493|bibcode=2000MNRAS.318..203S|issn=0035-8711|doi-access=free}}
Much of Seljak's recent work has been focused on how to extract fundamental properties of our universe from cosmological observations using analytical methods and numerical simulations. He has developed cosmological generative models of dark matter, stars and cosmic gas distributions.
Seljak is actively developing methods for accelerated approximate Bayesian methodologies, and applying them to cosmology, astronomy, and other sciences. Examples of this work are the MicroCanonical Hamiltonian and Langevin Monte Carlo and Deterministic Langevin Monte Carlo samplers.
Seljak is developing machine learning methods with applications to cosmology, astronomy, and other sciences. Notable examples include Fourier-based Gaussian processes for analysis of time and/or spatially ordered data, generative models with explicit physics symmetries (translation, rotation), and sliced iterative transport methods for density estimation and sampling.
=Honours and awards=
Seljak was awarded the 2021 Gruber Prize in Cosmology jointly with Marc Kamionkowski and Matias Zaldarriaga, who together "introduced numerous techniques for the study of the large-scale structure of the universe as well as the properties of its first instant of existence."{{Cite web |title=2021 Gruber Cosmology Prize |url=https://gruber.yale.edu/2021-gruber-cosmology-prize |access-date=6 May 2021 |website=gruber.yale.edu}}
- David and Lucille Packard Research Fellow (2000)
- Sloan Research Fellow (2001)
- Helen B. Warner Prize for Astronomy (2001)[http://aas.org/prizes/warner Warner prize recipients] {{Webarchive|url=https://web.archive.org/web/20101119191008/http://aas.org/prizes/warner|date=19 November 2010}}, AAS, retrieved 27 March 2011.
- Fellow of the American Physical Society (2013)
- Member of the US National Academy of Sciences (2019)
- Highest cited Slovenian scientist (2019)
- Wiki Science Competition international winner (2019-2020){{Cite web|url=https://commons.wikimedia.org/wiki/Commons:Wiki_Science_Competition_2019/Winners#Non-photographic_media|title = Commons:Wiki Science Competition 2019/Winners - Wikimedia Commons}}{{cite web |url=https://elementsmagazine.org/2020/07/31/lab-cosmologist-wins-science-photo-competition/ |title=Lab Cosmologist Wins Science Photo Competition |last= |first= |date=July 31, 2020 |website=Elements Archive |publisher= |access-date=August 15, 2023}}
- Gruber Prize in Cosmology (2021)
- Honorary Doctorate, University of Ljubljana (2023)
- Member of American Academy of Arts and Sciences (2024)
Notable students
References
{{Reflist|30em}}
{{Authority control}}
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Category:University of Ljubljana alumni
Category:Massachusetts Institute of Technology alumni
Category:Princeton University faculty
Category:University of California, Berkeley faculty
Category:Academic staff of the University of Zurich
Category:People from Nova Gorica
Category:Members of the United States National Academy of Sciences