# Sung-Sik Lee

McMaster University

Areas of research:

### Affiliations

Department of Physics and Astronomy, McMaster University

Perimeter Institute

Potential PhD students should submit an application to the Department of Physics and Astronomy at McMaster University.

Students interested in pursuing an MSc degree can apply either to Perimeter Institute's PSI program or directly to McMaster University

### Research Interests

Condensed matter systems consist of many particles that are the order of 10 to the 23rd power. At the microscopic level, the well-established rules of quantum mechanics govern the dynamics of individual particles. However, it is very challenging to predict the behaviors of a whole system, starting from the microscopic theory. For the past 30 years, it has become clear that collective behaviors are governed by organizing principles that are not manifest from microscopic rules of dynamics. The main goal of my research is to identify new dynamical principles that are behind novel emergent phenomena in critical states of quantum matter such as non-Fermi liquids. I am also interested in the interdisciplinary research areas between condensed matter physics, string theory, and gravitational theory. Recently I have developed the quantum renormalization group in which coupling constants in quantum field theories are promoted to dynamical variables. The quantum renormalization group provides a microscopic connection between general D-dimensional quantum field theories and (D+1)-dimensional quantum theories of gravity as conjectured by the AdS/CFT correspondence. I am trying to use it to better understand quantum field theories, quantum gravity, and the holographic principle.

### Positions Held

- July 2018 --- present : Department of Physics and Astronomy, McMaster University, Professor
- July 2012 - June 2018 : Department of Physics and Astronomy, McMaster University, Associate Professor
- July 2007 - June 2012 : Department of Physics and Astronomy, McMaster University, Assistant Professor
- July 2006 --- June 2007 : Post doctoral researcher, Kavli Institute for Theoretical Physics, Santa Barbara
- Mar. 2004 --- Jul. 2006 : Post doctoral researcher, Massachusetts Institute of Technology
- Nov. 2002 --- Feb. 2004: Post doctoral researcher, Pohang University of Science and Technology

### Awards

- Early Research Award, $100,000 for five years, Ontario Ministry of Research and Innovation

### Recent Publications

- H. Ma, S.-S. Lee, "Constraints on beta functions in field theories", SciPost Phys. 12, 046 (2022), arXiv: 2009.11880
- W. Ye, S.-S. Lee, L. Zou, "Ultraviolet-Infrared Mixing in Marginal Fermi Liquids", Phys. Rev. Lett. 128, 106402 (2022), arXiv: 2109.00004
- S.-S, Lee, "Clock-dependent spacetime", J. High Energy Phys. 2021, 204 (2021), arXiv: 2012.14416
- S.-S. Lee, "A model of quantum gravity with emergent spacetime", JHEP 2020, 70 (2020), arXiv: 1912.12291
- J. M. Lee, C. Geng, J. W. Park, M. Oshikawa, S.-S. Lee, H. W. Yeom, G. Y. Cho, ``Flat Bands, Topology, and Superconductivity of "Magic" Honeycomb Network in TaS2'', Phys. Rev. Lett. 124, 137002 (2020), arXiv: 1907.00012.
- S.-S. Lee, ``State dependent spread of entanglement in relatively local Hamiltonians'', JHEP (2019) 2019: 215, arXiv: 1811.07241
- S.-S. Lee, ``Emergent gravity from relatively local Hamiltonians and a possible resolution of the black hole information puzzle'', JHEP (2018) 2018: 43, arXiv: 1803.00556
- A. Schlief, P. Lunts, S.-S. Lee, "Noncommutativity between the low-energy limit and integer dimension limits in the epsilon-expansion: a case study of the antiferromagnetic quantum critical metal", Phys. Rev. B 98, 075140 (2018)
- S.-S. Lee, "Recent Developments in Non-Fermi Liquid Theory", Annual Review of Condensed Matter Physics Vol. 9:227-244 (2018)
- Q. Hu, S.-S. Lee, ``Non-local Geometry inside Lifshitz Horizon", JHEP 07 (2017) 56, arXiv: 1703.07522.
- P. Lunts, A. Schlief, S.-S. Lee, ``Emergence of a control parameter for the antiferromagnetic quantum critical metal", Phys. Rev. B 95, 245109 (2017), arXiv: 1701.08218.
- A. Schlief, P. Lunts, S.-S. Lee, ``Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions'', Phys. Rev. X 7, 021010 (2017), arXiv: 1608.06927.
- S. Sur and S.-S. Lee, ``Anisotropic Non-Fermi Liquids", Phys. Rev. B 94, 195135 (2016), arXiv: 1606.06694.
- S.-S. Lee, ``Horizon as Critical Phenomenon'', JHEP (2016) 2016: 44, arXiv: 1603.08509.
- P. Lunts, S. Bhattacharjee, J. Miller, E. Schnetter, Y. B. Kim, S.-S. Lee, "Ab initio holography", JHEP 08 (2015) 107, arXiv: 1503.06474
- S. Ghamari, S.-S. Lee and C. Kallin, ``RG Analysis on a Neck-Narrowing Lifshitz Transition in the Presence of Weak Short-Range Interactions in Two Dimensions", Phys. Rev. B 92, 085112 (2015) , arXiv: 1407.6732.
- I. Mandal and S.-S. Lee, ``UV/IR mixing in Non-Fermi Liquids", Phys. Rev. B 92, 035141 (2015), arXiv: 1407.0033.
- S. Sur and S.-S. Lee, "Quasi-Local Strange Metal", Phys. Rev. B 91, 125136 (2015), arXiv: 1405.7357.
- S. Sur and S.-S. Lee, ``Chiral non-Fermi liquids", Phys. Rev. B 90, 045121 (2014), arXiv: 1310.7543
- Sung-Sik Lee, "Quantum Renormalization Group and Holography", JHEP 01, 076 (2014), arXiv: 1305.3908.
- P. Ponte and S.-S. Lee, ``Emergence of supersymmetry on the surface of three dimensional topological insulators'', New J. Phys. 16, 013044 (2014), arXiv : 1206.2340
- Denis Dalidovich and Sung-Sik Lee, "Perturbative non-Fermi liquids from dimensional regularization", Phys. Rev. B 88, 245106 (2013), arXiv: 1307.3170
- Marlon Rodney, H. Francis Song, Sung-Sik Lee, Karyn Le Hur, Erik Sorensen, "Scaling of entanglement entropy across Lifshitz transitions", Phys. Rev. B 87, 115132 (2013)
- Sung-Sik Lee, "Background independent holographic description : From matrix field theory to quantum gravity", JHEP 1210 (2012) 160
- S.-S. Lee, ``Holographic Matter : Deconfined String at Criticality'', Nucl. Phys. B 862, 781 (2012), arXiv: 1108.2253.
- S. Bhattacharjee, S.-S. Lee and Y. B. Kim, ``Spin-Orbital Locking, Emergent Pseudo-Spin, and Magnetic order in Na2IrO3'', New J. Phys.14, 073015 (2012), arXiv: 1108.1806.
- S. Bhattacharjee, Y. B. Kim, S.-S. Lee, and D.-H. Lee, ``Fractionalized topological insulators from frustrated spin models in three dimensions'', Phys. Rev. B 85, 224428 (2012), arXiv: 1202.0291.
- S. Ghamari, C. Kallin, S.-S. Lee, and E. S. Sorensen, ``Order in a Spatially Anisotropic Triangular Antiferromagnet'', Phys. Rev. B 84, 174415 (2011), arXiv : 1108.3036.
- S.-S. Lee, ``Holographic description of large N gauge theory'', Nucl. Phys. B 851, 143 (2011), arXiv: 1011.1474.
- A. Bayntun, C.P. Burgess, Brian P. Dolan, S.-S. Lee, AdS/QHE: Towards a Holographic Description of Quantum Hall Experiments, New J.Phys.13:035012 (2011), arXiv: 1008.1917.
- F. Borges, A. Borissov, A. Singh, A. Schlief, S.-S. Lee, "Field-theoretic functional renormalization group formalism for non-Fermi liquids and its application to the antiferromagnetic quantum critical metal in two dimensions", arXiv: 2208.00730
- H. Ma, S.-S. Lee, "Exact effective action for the O(N) vector model in the large N limit", arXiv: 2107.05654

### Seminars

- "Functional renormalization group formalism for non-Fermi liquids and its application to the antiferromagnetic quantum critical metal", Conformal field theory and quantum many-body physics, Centre de Recherche de Mathematiques, Montreal, Aug. 2022
- "Emergent phenomena in quantum matter", Journeys into theoretical physics, ICTP, Sao Paulo, July 2022
- "Functional renormalization group formalism for non-Fermi liquids and its application to the antiferromagnetic quantum critical metal", Recent developments in strongly correlated quantum matter, NORDITA, June 2022
- "Effective action from quantum renormalization group", University of Illinois, Urbana-Champaign (virtual), Nov. 2021
- "Quantum renormalization group", University of Montreal (virtual), Oct. 2021
- ``A model of quantum gravity with emergent spacetime", Harvard University (virtual), September 2021
- "Clock-dependent spacetime", Emergence in Cosmology Workshop, Rotman Institute of Philosophy (virtual), Aug. 2021
- "State-dependent spread of entanglement in relatively local Hamiltonians", International Workshop: New Frontiers in Extremely Strongly Interacting Quantum Matter: Transport Dynamics, Quantum Hydrodynamics and Topological Matter, TD Lee Institute, Shanghai (virtual) July 2021
- ``Effective field theories of strange metals", All things EFT seminar Series (virtual), March 2021
- ``Field theories for non-Fermi liquids", Condensed matter seminar, Ohio State University (virtual), Nov. 2020
- ``A model of quantum gravity with emergent spacetime", String Seminar, Stanford University (virtual), Nov. 2020
- ``Model of quantum gravity with emergent spacetime", Workshop on quantum matter and quantum information with holography, APCTP (virtual), Aug. 2020
- ``Model of quantum gravity with emergent spacetime", Condensed matter seminar, University College London (virtual), April 2020
- ``Field theories for non-Fermi liquids", Winter School on gapless fermion - from Fermi liquids to Strange metals, Max Planck Institute, Dresden, February 2020
- ``Field theories for non-Fermi liquids", 2020 Theory Winter School, The National High Magnetic Laboratory, Tallahassee, Florida, January 2020
- ``Model of quantum gravity with emergent spacetime", High energy seminar, McGill University, January 2020
- ``Antiferromagnetic quantum critical metal", Quantum Ferromagnetism and Related Phenoemena, Max-Planck Institute, Dresden, May 2019
- "State dependent spread of entanglement in relatively local Hamiltonians", Quantum and Topological Matter meeting, Delta Institute, Amsterdam, March, 2019
- "State dependent spread of entanglement in relatively local Hamiltonians", Aspen Winter Conference, February 2019
- "State dependent spread of entanglement in relatively local Hamiltonians", Rutgers University, January 2019
- "State dependent spread of entanglement in relatively local Hamiltonians", Polchinski Science Symposium, KITP, Santa Barbara, December 2018
- "Emergent gravity from relatively local Hamiltonians", Quantum Information in quantum gravity, Galileo Galilei Institute for Theoretical Physics, Florence, Italy, June 2018
- "Emergent gravity from relatively local Hamiltonians", Emergent symmetries in Particle Physics, Cosmology and Condensed Matter Systems, Niels Bohr Institute, Copenhagen, Denmark, June 2018
- "Noncommutativity between the low-energy limit and integer dimension limits in the epsilon-expansion for the antiferromagnetic quantum critical metal", Correlated Electron Systems - Novel Development Workshop, William Fine Theoretical Physics Institute, May 2018
- "Emergent gravity from relatively local Hamiltonians", University of California, Santa Barbara, May, 2018
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", University of Minnesota, Minneapolis, April 2018
- "Field theories for non-Fermi liquids", APS March meeting tutorial, Los Angeles, March 2018
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", Chaos, duality and topology in condensed matter theory, Urbana-Champaign, Nov. 2017
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", University of Florida, Gainesville, October 2017
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", Summer Workshop on Quantum Criticality in Metallic Systems, Aspen, August 2017
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", Conference on Order, Fluctuations, and Strong Correlations: New Platforms and Developments, KITP, Santa Barbara, July 2017
- "Quantum Renormalization Group", Theory Canada, York University, May 2017
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", Quantum Materials Symposium, Muju, Korea, February 2017
- "Exact critical exponents for the antiferromagnetic quantum critical metal in two dimensions", Workshop on many-body entanglement and strongly correlated phenomena, Sanya, China, December. 2016
- "Horizon as critical phenomenon", Journey to the center of the bulk, Princeton Center for Theoretical Science, Princeton, October 2016
- "Low-energy effective theories for non-Fermi liquids", Rutgers University, September, 2016
- "Low energy effective theories for non-Fermi liquids", Lecture Series on Beyond Landau Fermi liquid and BCS superconductivity near quantum criticality and Real space renormalization group approach, APCTP, Pohang, June 2016
- "Quantum renormalization group and holography", Lecture Series on Beyond Landau Fermi liquid and BCS superconductivity near quantum criticality and Real space renormalization group approach, APCTP, Pohang, June 2016
- "Horizon as critical phenomenon", Workshop on Emergent properties of space-time, CERN, Switzerland, June 2016
- "Horizon as dynamical quantum phase transition", Conference on holography and quantum information, Yukawa Institute for theoretical physics, Japan, June, 2016
- "Quantum renormalization group", CIFAR Summer School, Toronto, April 2016
- "Low energy effective theories for metals", CIFAR Summer School, Toronto, April 2016
- "Quantum RG, tensor network and holography", Gauge/Gravity Duality and Condensed Matter Physics, Banff International Research Station, February 2016
- "Ab Inition Holography", Columbia University, Nov. 2015
- "Ab Inition Holography", Brock University, Oct. 2015
- "Ab Inition Holography", University of Florida, Tallahasse, Oct. 2015
- "Ab-Initio Holograph", International Workshop on Strings, Black Holes and Quantum Information, Tohoku University, Japan, September 2015
- "Ab-Initio Holograph", Beyond Quasiparticle, Aspen Center for Physics, August 2015
- "Quantum Renormalization Group", International Congress on Mathematical Physics, Santiago, Chile, July 2015
- "Ab-Initio Holograph", Entanglement in Strongly Correlated Quantum Matter, KITP, Santa Barbara, June 2015
- "Quasi-Local strange metal", POSTECH, Pohang, Korea, April 2015
- "Low energy effective theories for non-Fermi liquids", Pioneering symposium on Quantum Criticality and Emergent Phenomena, Daejeon, Korea, April 2015
- "Quasi-Local strange metal", Symposium on Quantum Criticality : Heavy Fermion Systems and Beyond, Rice University, Houston, March 2015
- "Ab-Initio Holograph", Simons Symposium on Quantum Entanglement, Puerto Rico, March 2015
- "Quasi-Local strange metal", Quantum Material Symposium, Muju, Korea, Feb. 2015
- "Ab-Initio Holograph", Workshop on Holographic Renormalization Group and Entanglement, Paris, January, 2015
- "Ab Inition Holography", University of Chicago, Dec. 2014
- "Low energy effective theories for non-Fermi liquids", Conference on Quantum Field theory, String Theory and Condensed Matter Physics, Orthodox Academy of Crete, September 2014
- "Quasi-local strange metal", 2014 IASTU summer forum on topology and strong correlation in condensed matter physics, Tsinghua university, June, 2014
- "Low energy effective theories for non-Fermi liquids", 2014 IASTU summer forum on topology and strong correlation in condensed matter physics, Tsinghua university, June, 2014
- "Quasi-local strange metal", Workshop on non-Fermi liquids, SITP, Stanford University, April 2014
- "Low energy effective theories for non-Fermi liquids", Condensed matter seminar, University of Illinois Urbana Champaign, March 2014
- "Quantum renormalization group and Holography", Physics of Emergence, University of Pittsburgh, Feb. 2014
- "Low energy effective theories for non-Fermi liquids", Beyond quasiparticle : New paradigm for quantum fluids, Aspen Center for Physics, Jan. 2014
- "Low energy effective theories for non-Fermi liquids", Condensed matter seminar, MIT, Nov. 2013
- "Quantum renormalization group and AdS/CFT", String Seminar, Stanford, Nov. 2013
- "Low energy effective theories for non-Fermi liquids", Condensed matter seminar, Stanford, Nov. 2013
- "Low energy effective theories for non-Fermi liquids", Condensed matter seminar, Harvard, Nov. 2013
- "Quantum renormalization group and Holography", Holography : from gravity to quantum matter, Issac Newton Institute, Cambridge, United Kingdom, Sept. 2013
- "Low energy effective theories for non-Fermi liquids in two dimensions", Bad metal behavior and Mott quantum criticality, APCTP, Pohang, Korea, July 2013
- "Quantum renormalization group and Holography", Workshop and Conference on Geometrical Aspects of Quantum States in Condensed Matter, ICTP, Trieste, Italy, July 2013
- "Quantum renormalization group and AdS/CFT", String Seminar, Caltech, April 2013
- "Quantum renormalization group and AdS/CFT", String Seminar, University of Michigan, Ann Abor, March 2013
- "Quantum renormalization group and AdS/CFT", Simons Symposium on Quantum Entanglement, Caneel Bay, St. John, Feb. 2013
- "From renormalization group to emergent gravity: holographic description of quantum many-body matter", Topology, Entanglement and Strong Correlations in Condensed Matter, University of Urbana Champaign, Nov. 2012
- "From renormalization group to emergent gravity: holographic description of quantum many-body matter", String Seminar, MIT, Nov. 2012
- "Emergent phenomena in condensed matter systems", Colloquium, Virginia Tech, Nov. 2012
- "From Renormalization Group to Emergent Gravity: Holographic Description of Quantum Many-body Systems", KITP Conference: Exotic Phases of Frustrated Magnets, KITP, Santa Barbara, Oct. 2012
- "Chiral non-Fermi liquids in two dimensions", Center for Quantum Materials Inaugural conference, Field Institute, Toronto, Sep. 2012
- "From renormalization group to emergent gravity: holographic description of quantum many-body systems", ICTP2012: Innovations in Strongly Correlated Electronic Systems, ICTP, Trieste, Italy, August 2012
- ``Non-Fermi liquids in two dimensions'', 2012 Canadian Association of Physicists Congress, Alberta, June 2012
- ``Quantum field theory and quantum gravity'', Theoretical Physics Workshop, University of Western Ontario, April 2012
- ``Emergent dimension and quantum critical point'', APS March meeting, Boston, March 2012
- ``Holographic matter; deconfined string at criticality", SPOCK meeting, University of Cincinnati, December 2011
- ``Holographic matter; deconfined string at criticality'', String Seminar, University of California, Berkeley, Nov. 2011
- ``Connections between new states of condensed matter and string'', Origins Colloquium, Origin Institute, McMaster University, Oct. 2011
- ``Holographic matter; deconfined string at criticality", Holographic Duality and Condensed Matter Physics, KITP, Santa Barbara, USA, September 2011
- ``Holographic matter; deconfined string at criticality", KIAS-YITP Joint Workshop on String Theory, Holography and Beyond, Seoul, Korea, September 2011
- ``Holographic Matter'', Workshop on Emergence in Field Theory, IAS, Nanyang Technological University, Singapore, Aug 2011
- ``Holographic matter; deconfined string at criticality", Conference on Cold Materials, Hot Nuclei, and Black Holes: Applied Gauge/Gravity Duality, ICTP, Trieste, Italy, August 2011
- PIRSA:20080013, Non-Fermi liquid theories, 2020-08-13, Online School on Ultra Quantum Matter
- PIRSA%3A20080013%2C%20Non-Fermi%20liquid%20theories%2C%202020-08-13%2C%20Online%20School%20on%20Ultra%20Quantum%20Matter
- %60%60Non-Fermi%20liquid%20theories%22%2C%20Summer%20School%20on%20Ultra%20Quantum%20Matter%20(virtual)%2C%20August%202020
- ``Non-Fermi liquid theories", Summer School on Ultra Quantum Matter (virtual), August 2020
- PIRSA%3A18060027%2C%20Emergent%20Gravity%20From%20Relatively%20Local%20Hamiltonians%20%2C%202018-06-18%2C%20Low%20Energy%20Challenges%20for%20High%20Energy%20Physicists%203
- PIRSA%3A16120009%2C%20Low%20energy%20field%20theories%20for%20non-Fermi%20liquids%2C%202016-12-07%2C%20Colloquium
- PIRSA%3A15110066%2C%20Welcome%20and%20Opening%20Remarks%2C%202015-11-05%2C%20PI-UIUC%20Joint%20Workshop%20on%20Strongly%20Correlated%20Quantum%20Many-Body%20Systems%202015
- PIRSA%3A15070061%2C%20Anisotropic%20Non-Fermi%20Liquids%20%2C%202015-07-10%2C%20Recent%20Progress%20on%20High%20Tc%20Superconductivity%20and%20Related%20Problems
- PIRSA%3A15040162%2C%20Low%20energy%20field%20theories%20for%20non-Fermi%20liquids%2C%202015-04-30%2C%204%20Corners%20Southwest%20Ontario%20Condensed%20Matter%20Physics%20Symposium%202015
- PIRSA%3A14010100%2C%20Low%20energy%20effective%20theories%20for%20non-Fermi%20liquids%2C%202014-01-10%2C%20Condensed%20Matter%20Group%20Meeting
- PIRSA%3A13050036%2C%20Quantum%20renormalization%20group%20and%20AdS%2FCFT%2C%202013-05-08%2C%20Emergence%20%26%20Entanglement%20II%202013
- PIRSA%3A12060028%2C%20TBA%2C%202012-06-08%2C%20Exploring%20AdS%2FCFT%20Dualities%20in%20Dynamical%20Settings
- PIRSA%3A12050033%2C%20Background%20Independent%20Holographic%20Description%20%3A%20From%20Matrix%20Field%20Theory%20to%20Quantum%20Gravity%2C%202012-05-22%2C%20String%20Seminars
- PIRSA%3A11100095%2C%20First%20Principle%20Construction%20of%20Holographic%20Duals%20%2C%202011-10-25%2C%20Tensor%20Networks%20for%20Quantum%20Field%20Theories%20Conference
- PIRSA%3A11100057%2C%20Quantum%20Order%20and%20Emergent%20Space%20in%20Holographic%20Phases%20of%20Matter%2C%202011-10-18%2C%20String%20Seminars
- PIRSA%3A10070001%2C%20Holographic%20description%20of%20quantum%20field%20theory%2C%202010-07-20%2C%20String%20Seminars
- PIRSA%3A10050087%2C%20Holographic%20description%20of%20quantum%20field%20theory%2C%202010-05-29%2C%20Emergence%20and%20Entanglement
- PIRSA%3A08120018%2C%20Emergent%20supersymmetry%20and%20holographic%20non-Fermi%20liquid%20%2C%202008-12-03%2C%20String%20Seminars
- PIRSA%3A07040033%2C%20Spin%20Liquid%20with%20Spinon%20Fermi%20Surface%3A%20Its%20Stability%20and%20Possible%20Application%20to%20the%20Organics%2C%202008-04-24%2C%20Southwestern%20Ontario%204-Corner%20Condensed%20Matter%20Symposium
- PIRSA%3A06030004%2C%20Dual%20gravity%20study%20of%20the%20(2%2B1)D%20compact%20U(1)%20gauge%20theory%20coupled%20with%20strongly%20interacting%20matter%20fields%2C%202006-03-06%2C%20Colloquium