Vijay Balasubramanian

Cathy and Marc Lasry Professor
2N3A, David Rittenhouse Laboratory
(215) 573-0982
(215) 898-2010 FAX

My work in particle physics has focused on basic questions concerning the nature of space and time. I have worked on the origin of the thermodynamics of gravitating systems and the apparent loss of quantum information in the presence of black holes. My work has shown ways in which the familiar smooth structure of space-time can emerge as a long-distance effective description of more complex underlying physical constructs. My work has also explored how the matter and forces whose existence is known from laboratory experiments and astrophysical measurements arise from a fundamental unified theory of forces, matter and spacetime. zz
My interests in the nature of information, and the ways it is produced, processed and transmitted have led to my present research in neuroscience. My ongoing work shows how numerous structural and functional aspects of the organization of sensory systems can be understood as adaptations to efficiently process the information in natural stimuli, subject to the metabolic, spatial, temporal and noise constraints inherent in biological computation. I aim to develop these ideas into a framework for explaining the structural and functional organization of cortical circuitry.
I have also written on problems in statistical inference and machine learning, and in particular on "Occam's Razor", i.e., the tradeoff between simplicity and accuracy in quantitative models.


Ph.D. in Theoretical Physics from Princeton University
M.S. in Computer Science from M.I.T.
B.S. degrees in Physics and Computer Science from M.I.T.

Research Interests: 

String Theory, Particle Physics, High Energy Physics, Neuroscience

Selected Publications: 

Four Dimensional Black Hole Microstates: From D-branes to Spacetime Foam. Vijay Balasubramanian (Pennsylvania U.) , Eric G. Gimon (UC, Berkeley & LBL, Berkeley), Thomas S. Levi (LBL, Berkeley) . UPR-1154-T, LBNL-60486, Jun 2006. 32pp.

Using cosmology to constrain the topology of hidden dimensions. Joan Simon (Pennsylvania U.) , Raul Jimenez (Pennsylvania U. & Carnegie Inst. Observ.) , Licia Verde (Pennsylvania U.) , Per Berglund (New Hampshire U.) , Vijay Balasubramanian (Pennsylvania U.) . UPR-T-1153:-UNH-06-04, May 2006. 4pp.

Information Recovery From Black Holes. Vijay Balasubramanian (Pennsylvania U.) , Donald Marolf (UC, Santa Barbara) , Moshe Rozali (British Columbia U. & Perimeter Inst. Theor. Phys.) . Apr 2006. 8pp.

Integrability versus information loss: A Simple example. Vijay Balasubramanian, Bartlomiej Czech, Klaus Larjo, Joan Simon (Pennsylvania U.) . UPR-T-1142, Feb 2006. 15pp.

Massless black holes and black rings as effective geometries of the D1-D5 system. Vijay Balasubramanian (Pennsylvania U.) , Per Kraus (UCLA) , Masaki Shigemori (Caltech) . UPR-1128-T, UCLA-TEP-05-25, CALT-68-2573, Aug 2005. 45pp.

The Library of Babel: On the origin of gravitational thermodynamics. Vijay Balasubramanian (Pennsylvania U.) , Jan de Boer (Amsterdam U.) , Vishnu Jejjala (Durham U., Dept. of Math.) , Joan Simon (Pennsylvania U.) . UPR-1127-7, ITFA-2005-37, DCTP-05-33, Aug 2005. 72pp.

The Library of Babel. Vijay Balasubramanian (Pennsylvania U.) , Vishnu Jejjala (Durham U., Dept. of Math.) , Joan Simon (Pennsylvania U.) . DCTP-05-21, UPR-1124-T, May 2005. 7pp.

V. Balasubramanian, M.J. Berry and D. Kimber. Metabolically efficient information processing. Neural Computation 13(4):799-816, 2001.

V. Balasubramanian and M.J. Berry. Evidence for metabolically efficient codes in the retina. Network 13(4):531-553, 2002.

K. Koch, J. McLean, M.J. Berry, P. Sterling, V. Balasubramanian, M.A. Freed. Efficiency of information transmission by retinal ganglion cells. Current Biology 14:1523-1530, 2004.