Anton Kapustin

Particle Theory Group, Caltech

March 27, 2013

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 1 / 13

Theory Group Members

Mark Wise

Clifford Cheung

John Schwarz

Hiroshi Ooguri

Sergei Gukov

Anton Kapustin

Sean Carroll (theoretical cosmology)

John Preskill (quantum information)

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 2 / 13

We have fun doing research

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 3 / 13

We try to be nice to graduate students

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 4 / 13

Mark Wise

Research topics: Particle Phenomenology, Cosmology

Beyond the Standard Model Physics

Baryon Number Violation

Neutrino masses

Dark Matter

Physics of Inflation

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 5 / 13

Cliff Cheung

Research interests: Particle Phenomenology, Cosmology, Quantum FieldTheory

Beyond the Standard Model Physics

Dark Matter

Supersymmetry

Twistor methods in Perturbative Gauge Theory and Gravity

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 6 / 13

John Schwarz

Research topic: String Theory

M5 branes

M2 branes

Superconformal field theories

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Hiroshi Ooguri

Research topics: String Theory, Quantum Field Theory, Condensed MatterTheory, Mathematical Physics

Holographic description of phases of matter

Supersymmetric gauge theories

D-branes on Calabi-Yau manifolds

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 8 / 13

Spatially modulated phases

Field theory in 4d is holographically dual to 5d theories with gravity onAdS space.T > 0 ↔ Black hole in AdSNonzero chemical potential ↔ Black hole is electrically chargedIf there is a 5d Chern-Simons term in the bulk action, the black hole hasan instability .The dual field theory undergoes a phase transition to a helical phase:translational symmetry is broken by a spontaneously generated currentdensity.Such phases have been conjectured to exist in superconductors in amagnetic field (FFLO phase) and in high-density nuclear matter.

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 9 / 13

Sergei Gukov

Research interests: Mathematical Physics, Quantum Field Theory

Supersymmetric gauge theories in various dimensions

Dualities and other non-perturbative physics

Quantum Knot Invariants

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 10 / 13

Quantum Knot Invariants

Imagine that this knotted curve is a worldline of a heavy particle (say, aquark). It interacts with gauge fields in the bulk.Imagine also that the gauge theory is invariant under arbitrarydeformations of the space-time (it is a Topological Quantum Field Theory).Then the vacuum-to-vacuum transition amplitude is a topological invariantof a knot.

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 11 / 13

Anton Kapustin

Research interests: Quantum Field Theory, Condensed Matter Theory,Mathematical Physics

Supersymmetric gauge theories in various dimensions

Dualities and other non-perturbative physics

Topological Field Theory

Non-relativistic Quantum Field Theory and its applications

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 12 / 13

Goldstone bosons without Lorenz invariance

In Lorenz-invariant theories spontaneous symmetry breaking (SSB) leadsto massless particles (Goldstone bosons).One such boson for every ”broken” generator, E ∼ |k|.In theories with only translational invariance the counting is morecomplicated: some generators give rise to 1/2 of a Goldstone boson only.Such Type II Goldstone bosons typically have a dispersion law E ∼ k2.Reason: vacuum charge density for some unbroken generators.Apart from true Goldstone bosons, there may also be ”almost-Goldstonebosons”, which have a nonzero mass. They are massive partners of Type IIGoldstone bosons.Applications: nuclear physics, condensed matter.

Anton Kapustin (Particle Theory Group, Caltech) March 27, 2013 13 / 13