David Wittman

Headshot of David Wittman

Associate Professor

One Shields Avenue
Physics Department
Davis, CA 95616

Office: 529 Physics Building
Phone: +1 (530) 554-2354
Fax: +1 (530) 554-2354
Email: dmwittman@ucdavis.edu

Personal Website: http://wittman.physics.ucdavis.edu

Research Interests:

Professor Wittman has discovered millions of galaxies as co-PI of the Deep Lens Survey, which was awarded over 100 nights on 4-m telescopes to study a representative sample of the universe. But discovering millions of galaxies was the easy part. He analyzed the galaxies' shapes to reveal subtle distortions caused by the gravitational fields of foreground masses, an effect called weak gravitational lensing. He was the first to detect cosmic shear, or weak lensing by the large-scale structure of the universe. He was also the first to detect a cluster of galaxies through its gravitational effects alone, and the first to combine source redshift information with lensing to probe structure in three dimensions (tomography). Because most matter is dark, these observations constrain the density of dark matter in the universe.

Professor Wittman is co-chair of the Weak Lensing Collaboration for the Large Synoptic Survey Telescope (LSST), which will be the biggest galaxy survey ever conducted. The LSST survey will cover half the sky, 1000 times more area than the Deep Lens Survey, and will measure 5-10 billion galaxies. He plans to use lensing with the LSST to study dark matter, dark energy, and the physics of gravity itself. Because lensing is sensitive to both the cosmic geometry and the growth of structure, and different theories of gravity prescribe different relationships between the two, LSST will be able to constrain theories of gravity at an interesting level. This in turn will yield insight into fundamental questions such as extra dimensions and how gravity might be unified with the other forces.

Research Areas

Career History

  • Ph.D., University of Arizona, 1997
  • Technical Staff at Bell Laboratories, Lucent Technologies from 1997-2004
  • Assistant Research Physicist, University of California, Davis, May, 2004
  • Assistant Professor, University of California, Davis, 2006

Honors

  • Fulbright Scholar, 2015
  • SPIE Scholarship in Optical Engineering, 1993