Freddy Cachazo

Freddy Cachazo's picture
Faculty

Areas of Research:
Mathematical Physics,
Quantum Fields and Strings
Phone: x8501

Research Interests

In recent years it has become clear that the scattering matrix of massless particles is a very special object. Massless particles are the backbone of our best theory of nature; the Standard Model of particle physics and gravity. In 2003, Witten succeeded in combining twistor theory and string theory to produce a new formulation for the scattering matrix of gauge bosons - massless particles of helicity plus or minus one. Since then finding a similar formulation for gravitons - particles with helicity plus or minus two - has been a very important open problem. In 2012, in collaboration with Y. Geyer (a PSI student), I found one such formulation. Not long after this first formulation was found, I found a second one with D. Skinner (a PI's PDF). All these constructions are based on four dimensional kinematics. A natural question is whether similar constructions can be found in any dimension. Such a general formulation could lead to a deeper understanding of field theory in general. In collaboration with E. Yuan (a PI graduate student) and S. He (a PI postdoctoral fellow), I found such a construction. It expresses the tree-level scattering matrices of gluons and gravitons in any dimensions as integrals over the moduli space of n-punctured spheres. More recently, important advances for understanding how to proceed towards loop level have been made in terms of higher genus Riemann surfaces. This is work in progress with H. Gomez.

Positions Held

  • September 2009 - June 2010 School of Natural Sciences. Institute for Advanced Study. Princeton NJ. Member.
  • 2005-present. Perimeter Institute. Faculty Member
  • 2002-2005 School of Natural Sciences. Institute for Advanced Study. Princeton NJ. Postdoctoral Member.

Awards

  • 2014 New Horizons Prize
  • 2012 CAP Herzberg Medal.
  • 2009 Gribov Medal, European Physical Society (EPS)
  • Early Reseach Award of Ontario (ERA).

Recent Publications

  • F. Cachazo, S. He and E. Y. Yuan, Scattering of Massless Particles: Scalars, Gluons and Gravitons, JHEP 1407, 033 (2014) [arXiv: 1309.0885 [hep-th]].
  • F. Cachazo and D. Skinner, Gravity from Rational Curves, Phys. Rev. Lett. 110, 161301 (2013) [arXiv: 1207.0741 [hep-th]].
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo and J. Trnka, Local Integrals for Planar Scattering Amplitudes, JHEP 1206, 125 (2012), arXiv: 1012.6032 [hep-th].
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo, A. Hodges and J. Trnka, A Note on Polytopes for Scattering Amplitudes, JHEP 1204, 081 (2012) arXiv: 1012.6030 [hep-th].
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo, S. Caron-Huot and J. Trnka, The All-Loop Integrand For Scattering Amplitudes in Planar N=4 SYM, JHEP {\bf 1101}, 041 (2011). arXiv: 1008.2958 [hep-th]
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo and J. Trnka, Unification of Residues and Grassmannian Dualities, JHEP 1101, 049 (2011). arXiv: 0912.4912 [hep-th]
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo, J. Trnka, Unification of Residues and Grassmannian Dualities, JHEP 1101 (2011) 049. arXiv: 0912.4912 [hep-th]
  • N. Arkani-Hamed, J. Bourjaily, F. Cachazo, J. Trnka, Local Spacetime Physics from the Grassmannian, JHEP 1101, 108 (2011). arXiv: 0912.3249 [hep-th]
  • N. Arkani-Hamed, F. Cachazo and C. Cheung, The Grassmannian Origin Of Dual Superconformal Invariance, JHEP {\bf 1003}, 036 (2010). arXiv: 0909.0483 [hep-th]
  • N. Arkani-Hamed, F. Cachazo, C. Cheung and J. Kaplan, A Duality For The S Matrix, JHEP 1003, 020 (2010). arXiv: 0907.5418 [hep-th].
  • N. Arkani-Hamed, F. Cachazo, C. Cheung and J. Kaplan, The S-Matrix in Twistor Space, JHEP 1003, 110 (2010). arXiv: 0903.2110 [hep-th].
  • N. Arkani-Hamed, F. Cachazo and J. Kaplan, What is the Simplest Quantum Field Theory?, JHEP 1009, 016 (2010). arXiv: 0808.1446 [hep-th].
  • F. Cachazo and E. Y. Yuan, Are Soft Theorems Renormalized?, arXiv: 1405.3413 [hep-th].
  • F. Cachazo and A. Strominger, Evidence for a New Soft Graviton Theorem, arXiv: 1404.4091 [hep-th].
  • F. Cachazo, S. He and E. Y. Yuan, Scattering of Massless Particles in Arbitrary Dimension, arXiv: 1307.2199 [hep-th].
  • F. Cachazo, S. He and E. Y. Yuan, Scattering in Three Dimensions from Rational Maps, arXiv: 1306.2962 [hep-th].
  • F. Cachazo, S. He and E. Y. Yuan, Scattering Equations and KLT Orthogonality, arXiv: 1306.6575 [hep-th].
  • F. Cachazo, Resultants and Gravity Amplitudes, arXiv: 1301.3970 [hep-th].
  • N. Arkani-Hamed, J. L. Bourjaily, F. Cachazo, A. B. Goncharov, A. Postnikov and J. Trnka, Scattering Amplitudes and the Positive Grassmannian, arXiv: 1212.5605 [hep-th].
  • F. Cachazo, L. Mason and D. Skinner, Gravity in Twistor Space and its Grassmannian Formulation, arXiv: 1207.4712 [hep-th].
  • F. Cachazo and Y. Geyer, A 'Twistor String' Inspired Formula For Tree-Level Scattering Amplitudes in N=8 SUGRA, arXiv: 1206.6511 [hep-th].
  • F. Cachazo, Fundamental BCJ Relation in N=4 SYM From The Connected Formulation, arXiv: 1206.5970 [hep-th].

Seminars

  • Plenary talk at STRINGS 2014 in Princeton USA.
  • Plenary talk at Quantum Gravity in Paris 2014. Paris. March 2014.
  • Seminar at Cornell University. September 2013
  • The Geometry of Scattering Amplitudes. BIRS. Banff. Calgary, Canada, August 2012.
  • STRINGS 2012, Munich, Germany, June 2012.
  • 2012 CAP Congress. Canadian Association of Physicists (CAP) General Meeting. University of Calgary, Calgary, Canada, June 2012
  • Amplitudes 2012, DESY, Hamburg, Germany, March 2012
  • Amplitudes 2011, University of Michigan, Michigan, USA, November 2011
  • Grassmannians and Scattering Amplitudes. Canadian Mathematical Society Meeting. Edmonton, Alberta, Canada. June 2011
  • Four Lectures on Scattering Amplitudes at Weak Coupling. Abdus Salam ICTP, Trieste, Italy. April 2011
  • Five Lectures on Introduction to Twistor Methods and the S-Matrix. String Theory Latin-American School. Sao Paolo, Brazil. December 2010.
  • PiTP. Aspects of Supersymmetry, Institute for Advanced Study, Princeton, New Jersey, USA, July 2010
  • XVIth European Workshop on String Theory, Spain, June 2010
  • Gribov-80 Memorial Symposium, Abdus Salam ICTP, Trieste, Italy, May 2010
  • Joint theory seminar, Harvard University, Cambridge, Massachusetts, USA, April 2010
  • The Simons Center for Geometry and Physics, New York, USA, February 2010
  • APS ``April" Meeting, Washington, DC, USA, February 2010
  • S-Matrix Theory. Abdus Salam ICTP. Trieste. Italy.
  • What is the simplest quantum field theory?. Strings 2008. CERN.
  • BIRS String Workshop, Banff, Alberta, Canada, February 2006
  • STRINGS 2005, University of Toronto, Canada, July 2005
  • CMS/CSHPM Summer 2005 Meeting, String Theory and Integrable Systems Session, University of Waterloo, Waterloo, Canada, June 2005
  • QCD and String Theory, KITP, Santa Barbara, USA, November 2004
  • 28th Johns Hopkins Workshop on Current Problems in Particle Theory: Hyperspace, Superspace, Theory Space and Outer Space, Baltimore, Maryland, USA, Jun 2004
  • PIRSA:12030003, String Theory (Review) - Lecture 14, 2012-03-02, 11/12 PSI - String Theory (Review)
  • PIRSA:12030002, String Theory (Review) - Lecture 13, 2012-03-01, 11/12 PSI - String Theory (Review)
  • PIRSA:12020063, String Theory (Review) - Lecture 12, 2012-02-29, 11/12 PSI - String Theory (Review)
  • PIRSA:12020062, String Theory (Review) - Lecture 11, 2012-02-28, 11/12 PSI - String Theory (Review)
  • PIRSA:12020061, String Theory (Review) - Lecture 10, 2012-02-27, 11/12 PSI - String Theory (Review)
  • PIRSA:12020058, String Theory (Review) - Lecture 9, 2012-02-24, 11/12 PSI - String Theory (Review)
  • PIRSA:12020057, String Theory (Review) - Lecture 8, 2012-02-23, 11/12 PSI - String Theory (Review)
  • PIRSA:12020056, String Theory (Review) - Lecture 7, 2012-02-22, 11/12 PSI - String Theory (Review)
  • PIRSA:12020055, String Theory (Review) - Lecture 6, 2012-02-21, 11/12 PSI - String Theory (Review)
  • PIRSA:12020051, String Theory (Review) - Lecture 5, 2012-02-17, 11/12 PSI - String Theory (Review)
  • PIRSA:12020050, String Theory (Review) - Lecture 4, 2012-02-16, 11/12 PSI - String Theory (Review)
  • PIRSA:12020049, String Theory (Review) - Lecture 3, 2012-02-15, 11/12 PSI - String Theory (Review)
  • PIRSA:12020048, String Theory (Review) - Lecture 2, 2012-02-14, 11/12 PSI - String Theory (Review)
  • PIRSA:12020047, String Theory (Review) - Lecture 1, 2012-02-13, 11/12 PSI - String Theory (Review)
  • PIRSA:11090120, Research Presentation - String Theory, 2011-09-16, String Seminars
  • PIRSA:11080125, Lie Groups & Lie Algebras - Lecture 5, 2011-08-26, 11/12 PSI - Orientation Weeks
  • PIRSA:11080124, Lie Groups & Lie Algebras - Lecture 4, 2011-08-25, 11/12 PSI - Orientation Weeks
  • PIRSA:11080123, Lie Groups & Lie Algebras - Lecture 3, 2011-08-24, 11/12 PSI - Orientation Weeks
  • PIRSA:11080122, Lie Groups & Lie Algebras - Lecture 2, 2011-08-23, 11/12 PSI - Orientation Weeks
  • PIRSA:11080121, Lie Groups & Lie Algebras - Lecture 1, 2011-08-22, 11/12 PSI - Orientation Weeks
  • PIRSA:11080037, Wrap-up Talk, 2011-08-06, Mathematica Summer School - 2011
  • PIRSA:11070093, Intro to Scattering Amplitudes, 2011-07-31, Mathematica Summer School - 2011
  • PIRSA:11030113, String Theory Review - Lecture 15, 2011-03-04, 10/11 PSI - String Theory (Review)
  • PIRSA:11030006, String Theory Review - Lecture 13, 2011-03-03, 10/11 PSI - String Theory (Review)
  • PIRSA:11030007, String Theory Review - Lecture 14, 2011-03-03, 10/11 PSI - String Theory (Review)
  • PIRSA:11030005, String Theory Review - Lecture 12, 2011-03-02, 10/11 PSI - String Theory (Review)
  • PIRSA:11030004, String Theory Review - Lecture 11, 2011-02-28, 10/11 PSI - String Theory (Review)
  • PIRSA:11020062, String Theory Review - Lecture 10, 2011-02-28, 10/11 PSI - String Theory (Review)
  • PIRSA:11020059, String Theory Review - Lecture 9, 2011-02-25, 10/11 PSI - String Theory (Review)
  • PIRSA:11020058, String Theory Review - Lecture 8, 2011-02-24, 10/11 PSI - String Theory (Review)
  • PIRSA:11020057, String Theory Review - Lecture 7, 2011-02-23, 10/11 PSI - String Theory (Review)
  • PIRSA:11020056, String Theory Review - Lecture 6, 2011-02-22, 10/11 PSI - String Theory (Review)
  • PIRSA:11020052, String Theory Review - Lecture 5, 2011-02-18, 10/11 PSI - String Theory (Review)
  • PIRSA:11020051, String Theory Review - Lecture 4, 2011-02-17, 10/11 PSI - String Theory (Review)
  • PIRSA:11020050, String Theory Review - Lecture 3, 2011-02-16, 10/11 PSI - String Theory (Review)
  • PIRSA:11020049, String Theory Review - Lecture 2, 2011-02-15, 10/11 PSI - String Theory (Review)
  • PIRSA:11020048, String Theory Review - Lecture 1, 2011-02-14, 10/11 PSI - String Theory (Review)
  • PIRSA:10080017, Space-time, Quantum Mechanics and Scattering Amplitudes - 5A, 2010-08-27, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080022, Space-time, Quantum Mechanics and Scattering Amplitudes, 2010-08-27, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080016, Space-time, Quantum Mechanics and Scattering Amplitudes, 2010-08-26, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080021, Space-time, Quantum Mechanics and Scattering Amplitudes, 2010-08-26, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080015, Space-time, Quantum Mechanics and Scattering Amplitudes - 3A, 2010-08-25, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080020, Space-time, Quantum Mechanics and Scattering Amplitudes - 3B, 2010-08-25, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080014, Space-time, Quantum Mechanics and Scattering Amplitudes - Lecture 2A, 2010-08-24, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080019, Space-time, Quantum Mechanics and Scattering Amplitudes - Lecture 2B, 2010-08-24, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080013, Space-time, Quantum Mechanics and Scattering Amplitudes - 1A, 2010-08-23, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10080018, Space-time, Quantum Mechanics and Scattering Amplitudes - 1B, 2010-08-23, Space-time, Quantum Mechanics and Scattering Amplitudes
  • PIRSA:10050042, What Do Grassmannians And Particle Colliders Have In Common?, 2010-05-09, Connections in Geometry and Physics 2010
  • PIRSA:10010093, String Theory - Review (PHYS 623) - Lecture 5, 2010-01-29, 09/10 PSI - String Theory (Review)
  • PIRSA:10010092, String Theory - Review (PHYS 623) - Lecture 4, 2010-01-28, 09/10 PSI - String Theory (Review)
  • PIRSA:10010091, String Theory - Review (PHYS 623) - Lecture 3, 2010-01-27, 09/10 PSI - String Theory (Review)
  • PIRSA:10010090, String Theory - Review (PHYS 623) - Lecture 2, 2010-01-26, 09/10 PSI - String Theory (Review)
  • PIRSA:10010089, String Theory - Review (PHYS 623) - Lecture 1, 2010-01-25, 09/10 PSI - String Theory (Review)
  • PIRSA:09010009, The S-matrix reloaded, 2009-01-21, Colloquium
  • PIRSA:05060092, Twistor String Theory and Perturbative Yang-Mills 3, 2005-06-25, Summer School: Strings, Gravity & Cosmology - 2005
  • PIRSA:05060074, Twistor String Theory and Perturbative Yang-Mills 2, 2005-06-21, Summer School: Strings, Gravity & Cosmology - 2005
  • PIRSA:05060072, Twistor String Theory and Perturbative Yang-Mills 1, 2005-06-20, Summer School: Strings, Gravity & Cosmology - 2005