## Steven Gubser

**Department/Program(s):**

- Physics

**Position:**Professor

**Title:**Professor of Physics

**Field:**High Energy Theory

**Office:**341 Jadwin Hall

**Phone:**609-258-5927

I work on string theory, black holes, heavy ion collisions, and aspects of condensed matter theory and theoretical cosmology.

I focus particularly on the gauge-string duality, which relates gauge theories in four flat spacetime dimensions to string theory in five or ten curved dimensions. The gauge theories that can be described in this way are relatives of quantum chromodynamics, which is the theory of quarks and gluons.

Here are some of the things that I've worked on in recent years:

- Black holes can superconduct.
- Black holes dual to super-Yang-Mills theory at finite chemical potential exhibit Fermi surfaces.
- The motion of ordinary smoke rings can be approximately described in terms of bosonic strings in a background field similar to a magnetic field.
- Quarks plowing through a thermal plasma of quarks and gluons lose energy at a rate that can be estimated using strings in anti-de Sitter space.
- Conformal symmetry can be used to help generate exact solutions to the relativistic Navier-Stokes equation that are similar to heavy-ion collisions.
- Classical string theory can sometimes be formulated entirely algebraically, without any calculus.

In 2010 I wrote a book on string theory entitled *The Little Book of String Theory*. You can find out more about it on the publisher's web page, and also here.

You can visit my homepage and my research group's page.

#### Recent Publications

- (with O. DeWolfe, C. Rosen, and D. Teaney) "Heavy ions and string theory,"
*Prog. Part. Nucl. Phys.***75**, 86-132, arXiv:1304.7794 [hep-th] (2014). - (with A. Ficnar) "Finite momentum at string endpoints,"
*Phys. Rev.***D89**, 026002, arXiv:1306.6648 [hep-th] (2014). - (with A. Ficnar and M. Gyulassy) "Shooting String Holography of Jet Quenching at RHIC and LHC,"
*Phys. Lett.***B738**, 464-471, arXiv:1311.6160 [hep-ph] (2014). - (with A. Ficnar and M. Gyulassy) "Holographic light quark jet quenching at RHIC and LHC via the shooting strings,"
*Nucl. Phys.***A932**, 264-268, arXiv:1404.0935 [hep-ph] (2014). - (with W. Song) "An axial gauge ansatz for higher spin theories,"
*JHEP***11**, 036, arXiv:1405.7045 [hep-th] (2014). - (with O. DeWolfe and C. Rosen) "Fermionic response in a zero entropy state of $\mathcal N=$ 4 super-Yang-Mills,"
*Phys. Rev.***D91**, 046011, arXiv:1312.7347 [hep-th] (2015). - (with R. Nayar and S. Parikh) "Strings, vortex rings, and modes of instability,"
*Nucl. Phys.***B892**, 156-180, arXiv:1408.2246 [hep-th] (2015). - (with W. van der Schee) "Complexified boost invariance and holographic heavy ion collisions,"
*JHEP***01**, 028, arXiv:1410.7408 [hep-th] (2015). - (with C. Cosnier-Horeau) "Holographic Fermi surfaces at finite temperature in top-down constructions,"
*Phys. Rev.***D91**, 066002, arXiv:1411.5384 [hep-th] (2015). - (with N. Callebaut, A. Samberg, and C. Toldo) "Segmented strings in AdS$_{3}$,"
*JHEP***11**, 110, arXiv:1508.07311 [hep-th] (2015). - (with O. DeWolfe, O. Henriksson, and C. Rosen) "Fermionic Response in Finite-Density ABJM Theory with Broken Symmetry," arXiv:1509.00518 [hep-th] (2015).
- (with Z. Saleem, S. Schoenholz, B. Stoica, and J. Stokes) "Nonlinear Sigma Models with Compact Hyperbolic Target Spaces," arXiv:1510.02129 [hep-th] (2015).
- (with B. Horn and S. Parikh) "Perturbations of vortex ring pairs," arXiv:1510.08059 [hep-th] (2015).
- "Evolution of segmented strings," arXiv:1601.08209 [hep-th] (2016).
- (with S. Parikh and P. Witaszczyk) "Segmented strings and the McMillan map," arXiv:1602.00679 [hep-th] (2016).