# Amit Sever

Institute for Advanced Study (IAS) - School of Natural Sciences (SNS)

Area of Research:

## Research Interests

My current main focus is in solving the simplest example of an interacting quantum field theory in four dimensions. The example in mind is N=4 SYM which is a non trivial conformal theory with maximal supersymmetry. Solving the theory means to be able to efficiently compute any observable in the theory at any values of the parameters. Solving an interacting QFT in four dimensions would be a huge theoretical achievement. I believe it will have implications on our understanding of nature. It will also become part of the text books of tomorrow and will play an analog role to the harmonic oscillator in quantum mechanics.

N=4 SYM is believed to be integrable (at least in the planar limit) and integrability is the main tool we use to solve it. So far, the problem of computing anomalous dimensions of all local operators in the theory has been solved. We are now mainly working on computing scattering amplitudes (or equivalently, polygon Wilson loops) using integrability. We have also started computing correlation functions, which is the next step in complexity.

## Positions Held

• 2011 - 2014 Institute for Advanced Studies, Princeton, Postdoctoral Fellow. (Joint appointment with PI from 2011 to 2013.)

## Recent Publications

• B. Basso, A. Sever and P. Vieira, Space-time S-matrix and Flux-tube S-matrix at Finite Coupling'', Phys Rev Lett (2013), arXiv: 1303.1396 [hep-th].
• A. Sever, P. Vieira and T. Wang, From Polygon Wilson Loops to Spin Chains and Back'', JHEP {\bf 1212}, 065 (2012),[arXiv: 1208.0841 [hep-th]].
• N. Gromov and A. Sever, Analytic Solution of Bremsstrahlung TBA'', JHEP {\bf 1211}, 075 (2012), [arXiv: 1207.5489 [hep-th]].
• D. Correa, J. Maldacena and A. Sever, The quark anti-quark potential and the cusp anomalous dimension from a TBA equation,'' arXiv: 1203.1913 [hep-th]. JHEP
• D. Correa, J. Henn, J. Maldacena and A. Sever, The cusp anomalous dimension at three loops and beyond,'' JHEP 1205, 098 (2012) [arXiv: 1203.1019 [hep-th]].
• D. Correa, J. Henn, J. Maldacena and A. Sever, An exact formula for the radiation of a moving quark in N=4 super Yang Mills,'' JHEP 1206}, 048 (2012) [arXiv: 1202.4455 [hep-th]].
• N. Gromov, A. Sever and P. Vieira, Tailoring Three-Point Functions and Integrability III. Classical Tunneling,'' JHEP 1207, 044 (2012) [arXiv: 1111.2349 [hep-th]].
• A. Sever, P. Vieira and T. Wang, OPE for Super Loops,'' JHEP 1111, 051 (2011) [arXiv: 1108.1575 [hep-th]].
• A. Sever and P. Vieira, Multichannel Conformal Blocks for Polygon Wilson Loops,'' JHEP 1201, 070 (2012) [arXiv: 1105.5748 [hep-th]].
• J. Escobedo, N. Gromov, A. Sever and P. Vieira, Tailoring Three-Point Functions and Integrability II. Weak/strong coupling match,'' JHEP 1109, 029 (2011) [arXiv: 1104.5501 [hep-th]].
• D. Gaiotto, J. Maldacena, A. Sever and P. Vieira, Pulling the straps of polygons,'' JHEP 1112, 011 (2011) [arXiv: 1102.0062 [hep-th]].
• J. Escobedo, N. Gromov, A. Sever and P. Vieira, Tailoring Three-Point Functions and Integrability,'' JHEP 1109, 028 (2011) [arXiv: 1012.2475 [hep-th]].
• D. Gaiotto, J. Maldacena, A. Sever and P. Vieira, Bootstrapping Null Polygon Wilson Loops,'' JHEP 1103, 092 (2011) [arXiv: 1010.5009 [hep-th]].
• L. F. Alday, D. Gaiotto, J. Maldacena, A. Sever and P. Vieira, An Operator Product Expansion for Polygonal null Wilson Loops,'' JHEP 1104, 088 (2011) [arXiv: 1006.2788 [hep-th]].
• L. F. Alday, J. Maldacena, A. Sever and P. Vieira, Y-system for Scattering Amplitudes,'' J. Phys. A 43, 485401 (2010) [arXiv: 1002.2459 [hep-th]].
• A. Sever, Non-commutative holography and scattering amplitudes in a large magnetic background,'' JHEP 0904, 039 (2009) [arXiv: 0901.4374 [hep-th]].
• J.~McGreevy and A.~Sever, Planar scattering amplitudes from Wilson loops,'' JHEP 0808, 078 (2008), arXiv: 0806.0668 [hep-th].
• J.~McGreevy and A.~Sever, Quark scattering amplitudes at strong coupling,'' JHEP {\bf 0802}, 015 (2008), arXiv: 0710.0393 [hep-th].
• B. Basso, A. Sever and P. Vieira, Space-time S-matrix and Flux tube S-matrix II. Extracting and Matching Data'', arXiv: 1306.2058 [hep-th].
• A. Sever and P. Vieira, Symmetries of the N=4 SYM S-matrix,'' arXiv: 0908.2437 [hep-th].

## Seminars

• Ecole normale superieure, Paris, The quark-antiquark potential in N=4 SYM"
• Joint IIP-ICTP Workshop on Gravity and String Theory, The quark-antiquark potential in N=4 SYM"
• ICTP-SAIFR Theory seminar, Color flux, Integrability and the S-matrix of N=4 SYM
• ICTP-SAIFR, Physics Colloquium, Gauge theories through the 't Hooft string"
• Israel Institute for Advanced Studies, Jerusalem, Integrability in Gauge and String Theory", The quark-antiquark potential in N=4 SYM"
• Isaac Newton Institute, Cambridge, Recent Advances in Scattering Amplitudes", The quark anti-quark potential and the generalized cusp anomalous dimension at any coupling"
• Tel Aviv University, The quark-antiquark potential in N=4 SYM"
• University of Amsterdam, Gauge theories through the t Hooft string"
• Nordita, Stockholm, Exact Results in Gauge-String Dualities", The quark anti-quark potential and the cusp anomalous dimension from a TBA equation"
• MIT, High energy seminar, Flux Tubes, Integrability and the S-matrix of N=4 SYM"
• Brandeis University, High energy seminar, Flux Tubes, Integrability and the S-matrix of N=4 SYM"
• Harvard University, Duality seminar, Flux Tubes, Integrability and the S-matrix of N=4 SYM"
• Brown University Strings Seminar, Flux Tubes, Integrability and the S-matrix of N=4 SYM"
• The Technion, Theory seminar, Solving gauge theories in 3+1 dimensions using spin chains dynamics"
• Tel Aviv University, Solving gauge theories in 3+1 dimensions using spin chains dynamics"
• University of Minnesota, Fine Theoretical Physics Institute, High Energy Theory Seminar, Flux Tubes, Integrability and the S-matrix of N=4 SYM"
• The Hebrew University, High energy seminar, Solving gauge theories in 3+1 dimensions using spin chains dynamics"
• Institute for Advanced Study, Princeton, High Energy Theory Seminar, `Flux Tubes, Integrability and the S-matrix of N=4 SYM"