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BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240415T090000
DTEND;TZID=America/New_York:20240524T170000
DTSTAMP:20260413T022210
CREATED:20230904T173915Z
LAST-MODIFIED:20240624T181936Z
UID:10000003-1713171600-1716570000@cmsa.fas.harvard.edu
SUMMARY:Program on Mathematical Aspects of Scattering Amplitudes
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Program \nDates: April 15 – May 24\, 2024 \nLocation: Harvard CMSA\, 20 Garden Street\, Cambridge\, MA 02138 \nThis program will bring together and foster interaction between theoretical physicists and mathematicians working on various topics connected to recent developments in our understanding of scattering amplitudes in quantum field theory. The field has advanced considerably since 2019 when the CMSA hosted the program “Spacetime and Quantum Mechanics\, Total Positivity and Motives.” Recent developments have primed this area for further significant advances\, which will be facilitated by bringing together many of the relevant experts for intensive discussion and collaboration. \nThe program will feature a weekly seminar series. \nTuesday\, April 16\, 2024\n4:15 pm\nSabrina Pasterski\, Perimeter Institute\nTitle: Radiation in Holography \n[Physics Talk]\nWednesday\, April 17\, 2024\n4:30 pm –  Cruft 309\nAna-Maria Raclariu\, King’s College London \nThursday\, April 18\, 2024\n4:15 pm\nLionel Mason\, University of Oxford\nTitle: Hidden symmetries of SD Poincare Einstein metrics in split signature \n[Physics Talk]\nTuesday\, April 23\, 2024\n4:30 pm – Jefferson 256\nJuan Maldacena\, Institute for Advanced Study \nThursday\, April 25\, 2024\n4:15 pm\nTomasz Taylor\, Northeastern University\nTitle: Progress in Yang-Mills-Liouville Theory \n[CMSA Colloquium]\nMonday\, April 29\, 2024\n4:30 – 5:30 pm\nLance Dixon\, Stanford\nTitle: The DNA of Particle Scattering \nTuesday\, April 30\, 2024\n9:00 am- Jefferson 453\nNima Arkani-Hamed\, IAS\nTitle: Surfaceology and the Real World Part 1 \n1:00 pm – Jefferson 453\nNima Arkani-Hamed\, IAS\nTitle: Surfaceology and the Real World Part 2 \n4:00 pm – Jefferson 453\nNima Arkani-Hamed\, IAS\nTitle: Surfaceology and the Real World Part 3 \nWednesday\, May 1\, 2024\n11:00 am – Science Center 507\nJaroslav Trnka\, UC Davis\nTitle: Loops of loops expansion in the Amplituhedron \n3:00 pm\nYu-tin Huang\, National Taiwan University\nTitle: Loop in trees: Chambers in amplitudes and correlation functions \n4:00 pm\nLivia Ferro\, University of Hertfordshire\nTitle: Scattering Amplitudes from Null-cone Geometry \n5:00 pm\nStephan Stieberger\, Max Planck Institute\nTitle: One-loop Double Copy Relation in String Theory and Twisted (Co)homology \nThursday\, May 2\, 2024\n11:00 am – Science Center 310\nDaniil Rudenko\, Chicago\nTitle: Introduction to Cluster Polylogarithms \nFriday\, May 3\, 2024\n11:00 am\nAndrew McLeod\, Edinburgh\nTitle: Genealogical Constraints on Feynman Integrals \nTuesday\, May 7\, 2024\n3:00 pm\nJacob Bourjaily\, Penn State\nTitle: The Algebraic and Transcendental Structure of Perturbative QFT \nWednesday\, May 8\, 2024\n3:00 pm\nRuth Britto\, Trinity\nTitle: Cuts and Symbols \nTuesday\, May 14\, 2024\n3:00 pm\nJames Drummond\, University of Southampton\nTitle: Multiple light-like Wilson loops in N=4 super Yang-Mills theory \nWednesday\, May 15\, 2024\n3:00 pm\nMatteo Parisi\, Harvard CMSA\nTitle: The amplituhedron and cluster algebras \nTuesday\, May 21\, 2024\n11:00 am\nMichael Borinsky\, ETH Zurich\nTitle: On the Euler characteristic of the commutative graph complex and the top-weight cohomology of the moduli space of curves \nWednesday\, May 22\, 2024\n11:00 am\nChaim Even-Zohar\, Technion\nTitle: Amplituhedron tiles and twistor polynomials \n  \nOrganizers: \n\nNima Arkani-Hamed (Institute for Advanced Study)\nMarcus Spradlin (Brown University)\nAndrew Strominger (Harvard University)\nAnastasia Volovich (Brown University)\nLauren Williams (Harvard University)\n\nParticipants: \n\n\nMichael Borinsky\, ETH Zurich\nJacob Bourjaily\, Pennsylvania State University\nRuth Britto\, Trinity College\nLance Dixon\, Stanford Linear Accelerator Center\nJames Drummond\, University of Southampton\nChaim Even-Zohar\, Technion\nLivia Ferro\, University of Hertfordshire\nCarolina Figueiredo\, Princeton University\nHadleigh Frost\, Oxford University\nBruno Gimenez\, University of Southampton\nOmer Gurdogan\, University of Southampton\nXuhua He\, Chinese University of Hong Kong\nPaul Heslop\, Durham University\nYu-Tin Huang\, National Taiwan University\nDani Kaufman\, University of Copenhagen\nJianrong Li\, University of Vienna\nTomasz Lukowski\, University of Hertfordshire\nYelena Mandelshtam\, University of California\, Berkeley\nLionel Mason\, University of Oxford\nAndrew McLeod\, University of Edinburgh\nNatalie Paquette\, University of Washington\nMatteo Parisi\, Harvard University\nSabrina Pasterski\, Perimeter Institute\nDmitri Pavlov\, Max Planck Institute for Mathematics in the Sciences\, Leipzig\nLizzie Pratt\, University of California\, Berkeley\nClaudia Rella\, University of Geneva\nDaniil Rudenko\, University of Chicago\nGiulio Salvatori\, Max Planck Institute for Physics\nMelissa Sherman-Bennett\, Massachusetts Institute of Technology\nJonah Stalknecht\, University of Hertfordshire\nStephan Stieberger\, Max Planck Institute\nTomasz Taylor\, Northeastern University\nRan Tessler\, Weizmann Institute of Science\nHugh Thomas\, Université du Québec à Montréal\nJaroslav Trnka\, University of California\, Davis\nCristian Vergu\, Pennsylvania State University
URL:https://cmsa.fas.harvard.edu/event/scattering-amplitudes/
LOCATION:CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Event,Programs
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Page-88-from-2310.17727_crop.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240429T090000
DTEND;TZID=America/New_York:20240503T170000
DTSTAMP:20260413T022210
CREATED:20240105T071054Z
LAST-MODIFIED:20240624T182013Z
UID:10001119-1714381200-1714755600@cmsa.fas.harvard.edu
SUMMARY:Workshop on Global Categorical Symmetries
DESCRIPTION:The CMSA will be hosting a Workshop on Global Categorical Symmetries from April 29–May 3\, 2024. \nParticipation in the workshop is by invitation. \nThe workshop will hold three Symmetry Colloquia open to the community on Thursday\, May 2\, 2024. \nLocation:  Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nTime: 2:00 – 2:50 pm \nSpeaker: Clay Còrdova\, University of Chicago \nTitle: Particle-Soliton Degeneracies from Spontaneously Broken Non-Invertible Symmetry \nAbstract: We study non-invertible topological symmetry operators in massive quantum field theories in (1+1) dimensions. In phases where this symmetry is spontaneously broken we show that the particle spectrum often has degeneracies dictated by the non-invertible symmetry and we deduce a procedure to determine the allowed multiplets. These degeneracies are robust predictions and do not require integrability or other special features of renormalization group flows. We exhibit these conclusions in examples where the spectrum is known\, recovering soliton and particle degeneracies. For instance\, the Tricritical Ising model deformed by the subleading Z2 odd operator flows to a gapped phase with two degenerate vacua. This flow enjoys a Fibonacci fusion category symmetry which implies a threefold degeneracy of its particle states\, relating the mass of solitons interpolating between vacua and particles supported in a single vacuum. \n  \nLocation:  Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nTime: 3:00 – 3:50 pm \nSpeaker: Thomas Dumitrescu\, UCLA \nTitle: Symmetries\, Invertible Field Theories\, and Gauge Theory Phases \nAbstract: I will start with a brief overview of gauge theory phases in 3+1 dimensions through the lens of higher symmetries — in particular the realization of 1-form symmetries acting on loop order parameters. I will then review recent progress in refining this characterization using invertible field theories\, or equivalently symmetry protected topological phases (SPTs). This refinement leads to new results in gauge theories with fundamental matter\, such as quantum chromodynamics (QCD)\, which do not possess 1-form symmetries. I will explain why these theories must sometimes undergo a phase transition between their confining and Higgs regimes\, despite the fact that classic results and standard lore say they should be continuously connected. \n  \nLocation:  Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nTime: 4:30 – 5:20 pm \nSpeaker: Theo Johnson-Freyd\, Dalhousie University and Perimeter Institute \nTitle: The Universal Target Category \nAbstract: Hilbert’s Nullstellensatz says that the complex numbers C satisfy a universal property among all R-algebras: every not-too-large nonzero commutative R-algebra maps to C. Deligne proved a similar statement in categorical dimension 1: every not-too-large symmetric monoidal category over R maps to the category sVec of super vector spaces. In other words\, sVec (and not Vec!) is “algebraically closed”. These statements help explain why quantum field theory requires imaginary numbers and fermions. I will describe the universal symmetric monoidal higher category that extends the sequence C\, sVec\, …. This is joint work in progress with David Reutter\, and builds on closely-related work by GCS collaborators Freed\, Scheimbauer\, and Teleman and Schlank et al. \n  \nOrganizers:\nDan Freed (Harvard CMSA & Math)\nConstantin Teleman  (UC Berkeley) \nThis event is co-sponsored by the Simons Foundation. 
URL:https://cmsa.fas.harvard.edu/event/globalcomputing24/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Workshop
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Symmetry-Lectures-poster-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240501T110000
DTEND;TZID=America/New_York:20240501T120000
DTSTAMP:20260413T022210
CREATED:20240423T135245Z
LAST-MODIFIED:20240430T200942Z
UID:10003379-1714561200-1714564800@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Jaroslav Trnka\, University of California\, Davis \nTitle: Loops of loops expansion in the Amplituhedron
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5124_trnka/
LOCATION:Science Center 507\, 1 Oxford Street\, Cambridge\, 02138
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240501T150000
DTEND;TZID=America/New_York:20240501T160000
DTSTAMP:20260413T022210
CREATED:20240415T175837Z
LAST-MODIFIED:20240429T134856Z
UID:10003366-1714575600-1714579200@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Yu-tin Huang\, National Taiwan University \nTitle: Loop in trees: Chambers in amplitudes and correlation functions
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5124/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240501T160000
DTEND;TZID=America/New_York:20240501T170000
DTSTAMP:20260413T022210
CREATED:20240415T182314Z
LAST-MODIFIED:20240422T142214Z
UID:10003370-1714579200-1714582800@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Livia Ferro\, University of Hertfordshire \nTitle: Scattering Amplitudes from Null-cone Geometry
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_51242/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240501T170000
DTEND;TZID=America/New_York:20240501T180000
DTSTAMP:20260413T022210
CREATED:20240423T135511Z
LAST-MODIFIED:20240423T135511Z
UID:10003380-1714582800-1714586400@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Stephan Stieberger\, Max Planck Institute \nTitle: One-loop Double Copy Relation in String Theory and Twisted (Co)homology
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_51243/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240502T110000
DTEND;TZID=America/New_York:20240502T120000
DTSTAMP:20260413T022210
CREATED:20240415T174619Z
LAST-MODIFIED:20240502T144153Z
UID:10003364-1714647600-1714651200@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Daniil Rudenko\, U Chicago \nTitle: Introduction to Cluster Polylogarithms \nLocation: Harvard Science Center 310
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5224dr/
LOCATION:Harvard Science Center\, 1 Oxford Street\, Cambridge\, MA\, 02138
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240502T133000
DTEND;TZID=America/New_York:20240502T143000
DTSTAMP:20260413T022210
CREATED:20240416T181909Z
LAST-MODIFIED:20240430T131929Z
UID:10003376-1714656600-1714660200@cmsa.fas.harvard.edu
SUMMARY:Non-dispersive one-way signal amplification in sonic metamaterials
DESCRIPTION:Active Matter Seminar \nSpeaker: Jayson Paulose\, University of Oregon \nTitle: Control of parametric amplification in space-time modulated mechanical metamaterials \nAbstract: Active mechanical metamaterials harbor acoustic signal processing functionalities that are impossible to achieve in passive structures. Amplifying an elastic wave as it passes through the material is a prominent example\, with potential applications in acoustic signal processing and loss mitigation. The fundamental mechanism for signal amplification of this kind is the parametric amplifier–an oscillator whose stiffness is periodically modulated in time\, which can inject energy into mechanical oscillations. Typically\, parametric amplification occurs at distinct modulation frequencies that are trivially related to the resonance modes of the unmodulated system\, which restricts its utility for amplifying signals with complex spatial or spectral structure. In this talk\, I’ll show how spatial variation of the modulation phase in parametric oscillator networks enables amplification phenomena that are far richer than those achievable by uncoupled and uncoordinated parametric amplifiers. Examples include turning off parametric resonances for particular vibrational modes in small assemblies [1]\, and achieving nonreciprocal broadband amplification in periodic arrays [2]. The existence of parametric resonances is tied to the internal symmetries inherent to mechanical systems as well as the symmetries obeyed by the parametric variation in space and time\, through an exact theoretical framework that augments the standard Floquet analysis of space-time modulated systems. \n  \n[1] Melkani and Paulose\, arXiv:2310.08734 \n[2] Kruss and Paulose\, PRApplied17\, 024020 (2022)
URL:https://cmsa.fas.harvard.edu/event/active-matter-5224/
LOCATION:Jefferson 256\, 17 Oxford Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Active Matter Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Active-Matter-Seminar-05.02.2024-2.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240502T140000
DTEND;TZID=America/New_York:20240502T145000
DTSTAMP:20260413T022210
CREATED:20240415T162849Z
LAST-MODIFIED:20240417T181513Z
UID:10003356-1714658400-1714661400@cmsa.fas.harvard.edu
SUMMARY:Symmetry Colloquia - Global Categorical Symmetries
DESCRIPTION:Symmetry Colloquia – Global Categorical Symmetries \nMay 2\, 2024 \nLocation: Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nSpeaker: Clay Còrdova\, University of Chicago \nTitle:  Particle-Soliton Degeneracies from Spontaneously Broken Non-Invertible Symmetry \nAbstract: We study non-invertible topological symmetry operators in massive quantum field theories in (1+1) dimensions. In phases where this symmetry is spontaneously broken we show that the particle spectrum often has degeneracies dictated by the non-invertible symmetry and we deduce a procedure to determine the allowed multiplets. These degeneracies are robust predictions and do not require integrability or other special features of renormalization group flows. We exhibit these conclusions in examples where the spectrum is known\, recovering soliton and particle degeneracies. For instance\, the Tricritical Ising model deformed by the subleading Z2 odd operator flows to a gapped phase with two degenerate vacua. This flow enjoys a Fibonacci fusion category symmetry which implies a threefold degeneracy of its particle states\, relating the mass of solitons interpolating between vacua and particles supported in a single vacuum.
URL:https://cmsa.fas.harvard.edu/event/gcs24_cordova/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Event,Symmetry Colloquia
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Pages-from-2403.08883_2.47.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240502T150000
DTEND;TZID=America/New_York:20240502T155000
DTSTAMP:20260413T022210
CREATED:20240415T163531Z
LAST-MODIFIED:20240417T181737Z
UID:10003357-1714662000-1714665000@cmsa.fas.harvard.edu
SUMMARY:Symmetry Colloquia  - Global Categorical Symmetries
DESCRIPTION:Symmetry Colloquia – Global Categorical Symmetries \nMay 2\, 2024 \nLocation: Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nSpeaker: Thomas Dumitrescu\, UCLA \nTitle: Symmetries\, Invertible Field Theories\, and Gauge Theory Phases \nAbstract: I will start with a brief overview of gauge theory phases in 3+1 dimensions through the lens of higher symmetries — in particular the realization of 1-form symmetries acting on loop order parameters. I will then review recent progress in refining this characterization using invertible field theories\, or equivalently symmetry protected topological phases (SPTs). This refinement leads to new results in gauge theories with fundamental matter\, such as quantum chromodynamics (QCD)\, which do not possess 1-form symmetries. I will explain why these theories must sometimes undergo a phase transition between their confining and Higgs regimes\, despite the fact that classic results and standard lore say they should be continuously connected.
URL:https://cmsa.fas.harvard.edu/event/gcs24_dumitrescu/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Event,Symmetry Colloquia
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Pages-from-2312.16898_phase-transition.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240502T163000
DTEND;TZID=America/New_York:20240502T172000
DTSTAMP:20260413T022210
CREATED:20240415T163546Z
LAST-MODIFIED:20240422T153733Z
UID:10003358-1714667400-1714670400@cmsa.fas.harvard.edu
SUMMARY:Symmetry Colloquia  - Global Categorical Symmetries
DESCRIPTION:Symmetry Colloquia – Global Categorical Symmetries \nMay 2\, 2024 \nLocation: Room G-10\, CMSA\, 20 Garden Street\, Cambridge MA 02138 \nSpeaker: Theo Johnson-Freyd\, Dalhousie University and Perimeter Institute \nTitle: The Universal Target Category \nAbstract: Hilbert’s Nullstellensatz says that the complex numbers C satisfy a universal property among all R-algebras: every not-too-large nonzero commutative R-algebra maps to C. Deligne proved a similar statement in categorical dimension 1: every not-too-large symmetric monoidal category over R maps to the category sVec of super vector spaces. In other words\, sVec (and not Vec!) is “algebraically closed”. These statements help explain why quantum field theory requires imaginary numbers and fermions. I will describe the universal symmetric monoidal higher category that extends the sequence C\, sVec\, …. This is joint work in progress with David Reutter\, and builds on closely-related work by GCS collaborators Freed\, Scheimbauer\, and Teleman and Schlank et al.
URL:https://cmsa.fas.harvard.edu/event/gcs24_johnson-freyd/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Event,Symmetry Colloquia
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Pages-from-2105.15167_Johnson-Freyd.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240503T110000
DTEND;TZID=America/New_York:20240503T120000
DTSTAMP:20260413T022210
CREATED:20240430T205406Z
LAST-MODIFIED:20240501T155445Z
UID:10003385-1714734000-1714737600@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Andrew McLeod\, Edinburgh \nTitle: Genealogical Constraints on Feynman Integrals
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5324/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240506T163000
DTEND;TZID=America/New_York:20240506T173000
DTSTAMP:20260413T022210
CREATED:20240319T201629Z
LAST-MODIFIED:20240507T201738Z
UID:10000819-1715013000-1715016600@cmsa.fas.harvard.edu
SUMMARY:Liouville Theory and Weil-Petersson Geometry
DESCRIPTION:Colloquium \nSpeaker: Sarah Harrison (Northeastern University) \nTitle: Liouville Theory and Weil-Petersson Geometry \nAbstract: Two-dimensional conformal field theory is a powerful tool to understand the geometry of surfaces. Liouville conformal field theory in the classical (large central charge) limit encodes the geometry of the moduli space of Riemann surfaces. I describe an efficient algorithm to compute the Weil–Petersson metric to arbitrary accuracy using Zamolodchikov’s recursion relation for conformal blocks\, focusing on examples of a sphere with four punctures and generalizations to other one-complex-dimensional moduli spaces. Comparison with analytic results for volumes and geodesic lengths finds excellent agreement. In the case of M_{0\,4}\, I discuss numerical results for eigenvalues of the Weil-Petersson Laplacian and connections with random matrix theory. \nBased on work with K. Coleville\, A. Maloney\, K. Namjou\, and T. Numasawa.
URL:https://cmsa.fas.harvard.edu/event/colloquium-5624/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Colloquium
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-05.06.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240507T120000
DTEND;TZID=America/New_York:20240507T130000
DTSTAMP:20260413T022210
CREATED:20240207T190343Z
LAST-MODIFIED:20240813T155522Z
UID:10000693-1715083200-1715086800@cmsa.fas.harvard.edu
SUMMARY:On using ML for Economics
DESCRIPTION:CMSA Member Seminar \nSpeaker: Sergiy Verstyuk \nTitle: On using ML for Economics \nAbstract: I will introduce some tools from the field of machine learning and discuss how they can be leveraged to get a fresh perspective on economics.
URL:https://cmsa.fas.harvard.edu/event/member-seminar-5724/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Member Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Member-Seminar-05.07.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240507T140000
DTEND;TZID=America/New_York:20240507T150000
DTSTAMP:20260413T022210
CREATED:20240411T181320Z
LAST-MODIFIED:20240819T151524Z
UID:10000835-1715090400-1715094000@cmsa.fas.harvard.edu
SUMMARY:Real-time observables in horizon thermodynamics
DESCRIPTION:General Relativity Seminar \nSpeaker: Albert Law\, Stanford \nTitle: Real-time observables in horizon thermodynamics \nAbstract: Euclidean black hole 1-loop determinants have recently been shown to compute a renormalized thermal canonical partition function for free fields in Lorentzian signature. A key ingredient is a ‘quasinormal mode (QNM) character’\, whose Fourier transform equals the renormalized spectral density of the single-particle Hamiltonian. Using a static patch in de Sitter space as an example\, in this talk\, I will offer new perspectives on the QNM character\, including its connection with the local density of states for the single-particle quantum mechanical problem associated with the Klein-Gordon equation\, and its direct relationships with (thermal) correlators of the free fields. I will discuss how these considerations might point toward a generalization to interacting theories.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-5724/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-05.7.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240507T150000
DTEND;TZID=America/New_York:20240507T160000
DTSTAMP:20260413T022210
CREATED:20240415T175924Z
LAST-MODIFIED:20240417T200650Z
UID:10003367-1715094000-1715097600@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Jacob Bourjaily\, Penn State \nTitle: The Algebraic and Transcendental Structure of Perturbative QFT
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5724/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240508T150000
DTEND;TZID=America/New_York:20240508T160000
DTSTAMP:20260413T022210
CREATED:20240415T180235Z
LAST-MODIFIED:20240429T182143Z
UID:10003368-1715180400-1715184000@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Ruth Britto\, Trinity \nTitle: Cuts and Symbols
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_5824/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240509T103000
DTEND;TZID=America/New_York:20240509T113000
DTSTAMP:20260413T022210
CREATED:20240416T133629Z
LAST-MODIFIED:20240507T152049Z
UID:10000890-1715250600-1715254200@cmsa.fas.harvard.edu
SUMMARY:Computing periods of hypersurfaces and elliptic surfaces via effective homology
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: Eric Pichon-Pharabod\, Universite Paris-Saclay \nTitle: Computing periods of hypersurfaces and elliptic surfaces via effective homology \nAbstract: The period matrix of a smooth complex projective variety X encodes the isomorphism between its singular homology and its algebraic De Rham cohomology. Numerical approximations with sufficient precision of the entries of this matrix\, called periods\, allow to recover some algebraic invariants of the variety\, such as the Néron-Severi group in the case of surfaces. In this talk\, we will present a method relying on the computation of an effective description of the homology for obtaining such numerical approximations of the periods of hypersurfaces and elliptic surfaces.
URL:https://cmsa.fas.harvard.edu/event/agst-5924/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Algebraic-Geometry-in-String-Theory-05.09.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240510T100000
DTEND;TZID=America/New_York:20240510T113000
DTSTAMP:20260413T022210
CREATED:20240507T190917Z
LAST-MODIFIED:20240508T195139Z
UID:10001518-1715335200-1715340600@cmsa.fas.harvard.edu
SUMMARY:From quantum Hall to Hubbard physics in twisted bilayer graphene
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Eslam Khalaf (Harvard) \nTitle: From quantum Hall to Hubbard physics in twisted bilayer graphene \n\nAbstract: Early on it was noticed that twisted bilayer graphene (TBG) has elements in common with two paradigmatic examples of strongly correlated physics: Hubbard physics and quantum Hall physics. On the one hand\, TBG hosts flat topological Landau-level-like bands which realize quantum anomalous Hall states and orbital ferromagnetism under the right conditions. On the other hand\, these bands are characterized by concentrated charge density and show experimental signs of fluctuating magnetism\, and unconventional superconductivty; all characteristics of Hubbard-model-like physics. The emergence of fluctuating moments is particularly surprising\, as localized Wannier states do not exist in topological bands. I will discuss a phenomenological model for the flat bands in TBG that centers the concentration of charge density and\, relatedly\, the concentration of Berry flux. The bands obtained have excellent quantitative agreement with the Bistritzer-Macdonald model for realistic parameters. I will show that\, rather remarkably\, the model hosts decoupled flavor moments which despite being only power-law delocalized with infinite localization length\, have parametrically small overlap with each other. I will show how this unifies many of the observations in TBG and leads to a novel Mott semimetal phase for intermediate temperatures where moments are thermally disordered but charge fluctuations are mostly frozen.
URL:https://cmsa.fas.harvard.edu/event/qm_51024/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-05.10.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240510T120000
DTEND;TZID=America/New_York:20240510T130000
DTSTAMP:20260413T022210
CREATED:20240416T185907Z
LAST-MODIFIED:20240507T190133Z
UID:10000695-1715342400-1715346000@cmsa.fas.harvard.edu
SUMMARY:On the landscape of 4d N=2 SCFTs
DESCRIPTION:CMSA Member Seminar \nSpeaker: Robert Moscrop\, Harvard CMSA \nTitle: On the landscape of 4d N=2 SCFTs \nAbstract: Four-dimensional conformal field theories with sufficient (N = 2) supersymmetry are highly constrained. So much so\, there has been an ongoing effort to classify them using only information about their moduli space of vacua. In this talk\, I will review recent progress in this classification before detailing a subclass of theories for which the classification problem is particularly tractable.
URL:https://cmsa.fas.harvard.edu/event/member-seminar-51024/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Member Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Member-Seminar-05.10.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240513T110000
DTEND;TZID=America/New_York:20240513T120000
DTSTAMP:20260413T022210
CREATED:20240411T181646Z
LAST-MODIFIED:20240514T142424Z
UID:10003354-1715598000-1715601600@cmsa.fas.harvard.edu
SUMMARY:An analogue of non-interacting quantum field theory in Riemannian signature
DESCRIPTION:General Relativity Seminar \nSpeaker: Mikhail Molodyk\, Stanford \nTitle: An analogue of non-interacting quantum field theory in Riemannian signature \nAbstract: Recent advances using microlocal tools have led to constructions\, for wave operators on various classes of spacetimes\, of four distinguished Fredholm inverses which have the singular behavior required of retarded\, advanced\, Feynman\, and anti-Feynman propagators in QFT. Vasy and Wrochna have used these to define a QFT on asymptotically Minkowski spacetimes\, for which they construct Hadamard states described by asymptotic data at infinity. I will describe an analogue of this construction on Riemannian manifolds with two asymptotically conic ends\, defining quantum fields satisfying the Helmholtz equation and using scattering data to construct states satisfying a wavefront mapping-property version of the Hadamard condition. The absence of a spacetime interpretation lends itself to a sharper focus on the theory’s analytic structure\, from whose perspective the Feynman propagators are no less natural than the advanced/retarded ones. I will also highlight some differences between Feynman propagators defined as distinguished inverses and as time-ordered expectations. Based on joint work with András Vasy.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-51324/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-05.13.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240513T133000
DTEND;TZID=America/New_York:20240513T143000
DTSTAMP:20260413T022210
CREATED:20240509T150634Z
LAST-MODIFIED:20240509T162010Z
UID:10003386-1715607000-1715610600@cmsa.fas.harvard.edu
SUMMARY:Improving Mean-Field Theory for Quantum Magnets
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Junyi Zhang\, Johns Hopkins University \nTitle: Improving Mean-Field Theory for Quantum Magnets \nAbstract: Frustrated magnets have garnered significant attention because of their potential to host exotic spin liquids\, while many real material candidates exhibit magnetic orders.  Due to their proximity to spin liquid phases\, the semiclassical descriptions of these magnetic orders often fall short in capturing their intricate quantum behaviors. In this talk\, I will introduce an improved mean-field method\, named density-matrix mean-field theory (DMMFT)\, for these quantum magnets. Using local reduced density matrix\, DMMFT can systematically incorporate the quantum fluctuations beyond conventional mean-field theories. Notably\, it not only quantitatively evaluates the renormalization of order parameters induced by quantum fluctuations but also has the capability to detect the topological order of quantum phases. DMMFT offers an efficient approach to explore phases displaying unconventional quantum orders\, particularly beneficial for investigating frustrated spin systems in high spatial dimensions. \nRef: https://arxiv.org/abs/2401.06236
URL:https://cmsa.fas.harvard.edu/event/qm_51324/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-05.13.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240513T163000
DTEND;TZID=America/New_York:20240513T173000
DTSTAMP:20260413T022210
CREATED:20240130T151206Z
LAST-MODIFIED:20240508T203329Z
UID:10000814-1715617800-1715621400@cmsa.fas.harvard.edu
SUMMARY:Errors and Correction in Cumulative Knowledge
DESCRIPTION:Colloquium \nSpeaker: Madhu Sudan\, Harvard University \nTitle: Errors and Correction in Cumulative Knowledge \nAbstract: Societal accumulation of knowledge is a complex\, and arguably error-prone\, process. The correctness of new units of knowledge depends not only on the correctness of the new reasoning\, but also on the correctness of old units that the new one builds on. If left unchecked\, errors could completely ruin the validity of most of this knowledge so there must some error-correcting going on. What are the error-corrections processes employed in nature and how effective are they? In this talk\, we describe our attempts to model such phenomena using probablistic models – we describe models for growth of cumulative knowledge\, emergence of errors and methods to check for errors and eliminate them. We then analyze in this compound model\, when effects of errors may survive\, and when they are totally eliminated. \nThe central discovery in our work is the following optimistic statement: If we do checking correctly (most of the time) investing just a constant factor (<1) of our effort in checking (and saving the remaining constant factor towards deriving new units of knowledge)\, then effects of errors can be kept in check. Notably the amount of effort expended on checking does not scale with the volume of total knowledge or the depth of dependencies in the new units of knowledge\, either of which would be overwhelming. \nBased on the papers: \nIs this correct? Let’s check!\nOmri Ben-Eliezer\, Dan Mikulincer\, Elchanan Mossel\, Madhu Sudan\narXiv:2211.12301 \nErrors are Robustly Tamed in Cumulative Knowledge Processes\nAnna Brandenberger\, Cassandra Marcussen\, Elchanan Mossel\, Madhu Sudan\narXiv:2309.05638
URL:https://cmsa.fas.harvard.edu/event/colloquium-4124/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Colloquium
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-05.13.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240514T123000
DTEND;TZID=America/New_York:20240514T133000
DTSTAMP:20260413T022210
CREATED:20240424T200426Z
LAST-MODIFIED:20240510T202406Z
UID:10003382-1715689800-1715693400@cmsa.fas.harvard.edu
SUMMARY:Quasilocal mass for general domains in space
DESCRIPTION:CMSA Member Seminar \nSpeaker: Jue Liu \nTitle: Quasilocal mass for general domains in space \nAbstract: Diffeomorphism-invariant quasilocal mass in classical general relativity has been studied for decades\, but it is still an open problem how to define quasi-local mass for general domains with multiple boundaries in space. Using the Hamiltonian formulation\, we will provide a new way to define the nonnegative quasi-local mass\, and give recent progress in overcoming the difficulties.
URL:https://cmsa.fas.harvard.edu/event/member-seminar-51424/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Member Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Member-Seminar-05.14.24.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240514T150000
DTEND;TZID=America/New_York:20240514T160000
DTSTAMP:20260413T022210
CREATED:20240415T180344Z
LAST-MODIFIED:20240510T144105Z
UID:10003369-1715698800-1715702400@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: James Drummond\, University of Southampton\n \nTitle: Multiple light-like Wilson loops in N=4 super Yang-Mills theory
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_51424/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240515T150000
DTEND;TZID=America/New_York:20240515T160000
DTSTAMP:20260413T022210
CREATED:20240415T182551Z
LAST-MODIFIED:20240517T135756Z
UID:10003371-1715785200-1715788800@cmsa.fas.harvard.edu
SUMMARY:Mathematical Aspects of Scattering Amplitudes Lecture
DESCRIPTION:Mathematical Aspects of Scattering Amplitudes Lecture \nSpeaker: Matteo Parisi\, Harvard CMSA \nTitle: The amplituhedron and cluster algebras
URL:https://cmsa.fas.harvard.edu/event/scatteringamplitudes_51524/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Scattering Amplitudes Lectures
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240516T103000
DTEND;TZID=America/New_York:20240516T113000
DTSTAMP:20260413T022210
CREATED:20240416T133753Z
LAST-MODIFIED:20240514T183407Z
UID:10003374-1715855400-1715859000@cmsa.fas.harvard.edu
SUMMARY:Mirror symmetry and log del Pezzo surfaces
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: Franco Rota\, University of Glasgow \nTitle: Mirror symmetry and log del Pezzo surfaces \nAbstract: The homological mirror symmetry conjecture predicts a duality\, expressed in terms of categorical equivalences\, between the complex geometry of a variety X (the B side) and the symplectic geometry of its mirror object Y (the A side). Motivated by this\, we study a series of singular surfaces (called log del Pezzo). I will describe the category arising in the B side\, using the McKay correspondence and explicit birational geometry. I will discuss early results on the A side\, using the language of pseudolattices to focus on the special case of a smooth degree 2 del Pezzo surface. This is joint work with Giulia Gugiatti.
URL:https://cmsa.fas.harvard.edu/event/agist_51624/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Algebraic-Geometry-in-String-Theory-05.16.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240516T130000
DTEND;TZID=America/New_York:20240516T140000
DTSTAMP:20260413T022210
CREATED:20240416T181859Z
LAST-MODIFIED:20240510T175438Z
UID:10003377-1715864400-1715868000@cmsa.fas.harvard.edu
SUMMARY:Controlling chaotic advection in 2D active nematics
DESCRIPTION:Active Matter Seminar \nSpeaker: Kevin Mitchell\, University of California\, Merced \nTitle: Controlling chaotic advection in 2D active nematics \nAbstract: Recent years have seen a surge of interest in active materials\, in which energy injected at the microscale gives rise to mesoscale coherent motion. One prominent example is an active 2D “liquid crystal” composed of microtubules in the nematic phase. The activity is generated by molecular motors that consume ATP to generate local shearing between the microtubules. The resulting 2D fluid flow exhibits self-generated mesoscale chaotic dynamics with a characteristic folding and stretching pattern. We analyze this dynamics from the perspective of chaotic advection\, in which the fluid can be viewed as “stirred” by topological defects in the nematic order parameter. Typically\, these defects move in an irregular\, chaotic pattern. We explore conditions\, both theoretically and in experiments\, under which the topological defects can be coaxed to perform regular periodic motion\, thus bringing some degree of order to the chaos.
URL:https://cmsa.fas.harvard.edu/event/active-matter-51624/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Active Matter Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Active-Matter-Seminar-05.16.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240516T150000
DTEND;TZID=America/New_York:20240516T160000
DTSTAMP:20260413T022210
CREATED:20240510T170616Z
LAST-MODIFIED:20240510T175234Z
UID:10003387-1715871600-1715875200@cmsa.fas.harvard.edu
SUMMARY:Geometry of Generalized Lienard Equations\, Contact Geometry and Metriplectic Structure
DESCRIPTION:Speaker: Partha Guha\, Khalifa University\, Abu Dhabi \nTitle: Geometry of Generalized Lienard Equations\, Contact Geometry and Metriplectic Structure \nAbstract: We start with a self-contained brief review of the construction of non-standard Lagrangian and Hamiltonian structures using the Jacobi Last Multiplier for the (generalized) reduced Lienard equations satisfying Chiellini integrability condition\, we then explore its connection with the contact Hamiltonian mechanics. We also explore Lienard equations\, of reaction-diffusion class and conformal (or contact) Hamiltonian Structures. Finally\, we present the geometric formulation of the generalized Lienard equations in terms of metriplectic structure. \nJoint work with Jose Carinena and Anindya Ghose Choudhury
URL:https://cmsa.fas.harvard.edu/event/geometry_51624/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Special Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Geometry-and-Physics-Seminar-05.16.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240517T103000
DTEND;TZID=America/New_York:20240517T120000
DTSTAMP:20260413T022210
CREATED:20240411T151408Z
LAST-MODIFIED:20240425T140248Z
UID:10001514-1715941800-1715947200@cmsa.fas.harvard.edu
SUMMARY:Love and Naturalness
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Mikhail Ivanov (MIT) \nTitle: Love and Naturalness \nAbstract: Recent progress in gravitational wave astronomy has spurred the development of efficient tools to describe gravitational binary dynamics. One such tool is classical worldline effective field theory (EFT). In the first part of my talk\, I will show how to use this EFT for systematic studies of tidal heating and deformations (Love numbers) of compact objects. I will present a gauge-invariant definition of Love numbers and show how to extract them in a coordinate-independent way from scattering amplitudes of the gravitational Raman process. I will show that the worldline EFT exhibits strong fine-tuning when applied to black holes. This gives rise to a naturalness paradox associated with the vanishing of black hole static Love numbers. In the second part of my talk\, I will present a new symmetry of black holes (Love symmetry) that elegantly resolves this paradox. The Love symmetry is tightly connected to isometries of extremal black holes that appear in many holographic constructions. It also provides a curious example of IR/UV mixing\, which may give insights for other hierarchy problems.
URL:https://cmsa.fas.harvard.edu/event/qm_51724/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-04.26.2024.docx-1.png
END:VEVENT
END:VCALENDAR