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DTSTART;TZID=America/New_York:20250918T160000
DTEND;TZID=America/New_York:20250918T170000
DTSTAMP:20260630T142907
CREATED:20250904T162209Z
LAST-MODIFIED:20250910T174655Z
UID:10003777-1758211200-1758214800@cmsa.fas.harvard.edu
SUMMARY:Moduli spaces of 4d N=2 quantum field theories
DESCRIPTION:Differential Geometry and Physics Seminar  \nSpeaker: Robert Moscrop\, CMSA \nTitle: Moduli spaces of 4d N=2 quantum field theories \nAbstract: Supersymmetry endows quantum field theories with several rich algebraic and geometric structures associated to their moduli space of vacua\, providing powerful tools to study such theories non-perturbatively. For example\, in four-dimensional theories with eight supercharges\, the low energy dynamics of the theory is captured by an algebraic completely integrable system whose base is the Coulomb branch– a particular distinguished submanifold of the moduli space. This structure is so tightly constrained\, that there is an ongoing program to classify such theories purely by understanding their Coulomb branch geometry. In this talk\, I will give a gentle introduction to the geometry of the moduli spaces of 4d N=2 theories and\, time permitting\, discuss some recent results showcasing how the geometry of the Coulomb branch can be used to constrain certain physical quantities of the theory. \n  \n  \n 
URL:https://cmsa.fas.harvard.edu/event/dgphys_91825/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Differential Geometry and Physics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/DG-Physics-Seminar-9.18.2025-scaled.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250915T163000
DTEND;TZID=America/New_York:20250915T173000
DTSTAMP:20260630T142907
CREATED:20250904T152315Z
LAST-MODIFIED:20250904T152759Z
UID:10003776-1757953800-1757957400@cmsa.fas.harvard.edu
SUMMARY:Topological Manifolds – The First 100 Years
DESCRIPTION:Colloquium \nSpeaker: Michael Freedman (Harvard CMSA and Logical Intelligence) \nTitle: Topological Manifolds – The First 100 Years \nAbstract: I’ll review manifold topology in the topological category from its start with work of Rado (1925) and Kneser (1926) to the present. Work of Moise\, Mazur\, Kirby\, Siebenmann\, Sullivan\, Kruskal\, and the speaker will be discussed. In my view there is one pressing open question (the A-B slice problem). I will end with some thoughts on putting an AI to work on it. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/colloquium-91525/
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-9.15.2025-scaled.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250915T150000
DTEND;TZID=America/New_York:20250915T160000
DTSTAMP:20260630T142907
CREATED:20250910T193835Z
LAST-MODIFIED:20250910T194841Z
UID:10003788-1757948400-1757952000@cmsa.fas.harvard.edu
SUMMARY:Orientifolds for F-theory on K3 Surfaces
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Chuck Doran (Alberta/CMSA) \nTitle: Orientifolds for F-theory on K3 Surfaces \nAbstract: Compactification of F-theory on an elliptically fibered K3 surface provides a framework to encode type IIB string theory on elliptic curves\, with the Kaehler modulus of the elliptic curve encoded in the complex structure of the elliptic fibers. In work with Malmendier\, Mendez-Diez\, and Rosenberg we extend that perspective by examining F-theory orientifolds on elliptically fibered K3 surfaces and connecting them to D-brane classifications using real K-theory (KR-theory).  The real structures—antiholomorphic involutions—on our K3 surfaces connect the geometry with the physics\, providing a natural setting for understanding the interplay between elliptic fibration structures and D-brane classifications in F-theory. We construct Real normal forms with their associated antiholomorphic involutions and use this to make explicit the 2-torsion Brauer twist that relates our normal forms to the Jacobian (Weierstrass normal form) elliptic fibration\, including the realization of a representative for the twisting class as an Azumaya algebra. This all connects back to the physics by considering three families of real K3 surfaces whose string limits give the three different type IIB theories on P1 with four type I_0^∗ Kodaira fibers.
URL:https://cmsa.fas.harvard.edu/event/qft_91525/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QFT-and-Physical-Mathematics-9.15.25-scaled.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250911T090000
DTEND;TZID=America/New_York:20250912T170000
DTSTAMP:20260630T142907
CREATED:20250502T175902Z
LAST-MODIFIED:20251026T044243Z
UID:10003743-1757581200-1757696400@cmsa.fas.harvard.edu
SUMMARY:Big Data Conference 2025
DESCRIPTION:Big Data Conference 2025 \nDates: Sep. 11–12\, 2025 \nLocation: Harvard University CMSA\, 20 Garden Street\, Cambridge & via Zoom \nThe Big Data Conference features speakers from the Harvard community as well as scholars from across the globe\, with talks focusing on computer science\, statistics\, math and physics\, and economics. \nInvited Speakers \n\nMarkus J. Buehler\, MIT\nYiling Chen\, Harvard\nJordan Ellenberg\, UW Madison\nYue M. Lu\, Harvard\nPankaj Mehta\, BU\nNick Patterson\, Harvard\nGautam Reddy\, Princeton\nTrevor David Rhone\, Rensselaer Polytechnic Institute\nTess Smidt\, MIT\n\nOrganizers: \nMichael M. Desai\, Harvard OEB |  Michael R. Douglas\, Harvard CMSA | Yannai A. Gonczarowski\, Harvard Economics | Efthimios Kaxiras\, Harvard Physics | Melanie Weber\, Harvard SEAS \n  \nBig Data Youtube Playlist \n  \nSchedule \nThursday\, Sep. 11\, 2025 \n  \n\n\n\n9:00 am\nRefreshments\n\n\n9:30 am\nIntroductions\n\n\n9:45–10:45 am\nGautam Reddy\, Princeton \nTitle: Global epistasis in genotype-phenotype maps\n\n\n10:45–11:00 am\nBreak\n\n\n11:00 am –12:00 pm\nNick Patterson\, Harvard \nTitle: The Origin of the Indo-Europeans \nAbstract: Indo-European is the largest family of human languages\, with very wide geographical distribution and more than 3 billion native speakers. How did this family arise and spread? This question has been discussed for nearly 250 years but with the advent of the availability of DNA from ancient fossils is now largely understood\, at least in broad outlines. We will describe what we now know about the origins.\n\n\n12:00–1:30 pm\nLunch break\n\n\n1:30–2:30 pm\nMarkus Buehler\, MIT \nTitle: Superintelligence for scientific discovery \nAbstract: AI is moving beyond prediction to become a partner in invention. While today’s models excel at interpolating within known data\, true discovery requires stepping outside existing truths. This talk introduces superintelligent discovery engines built on multi-agent swarms: diverse AI agents that interact\, compete\, and cooperate to generate structured novelty. Guided by Gödel’s insight that no closed system is complete\, these swarms create gradients of difference – much like temperature gradients in thermodynamics – that sustain flow\, invention\, and surprise. Case studies in protein design and music composition show how swarms escape data biases\, invent novel structures\, and weave long-range coherence\, producing creativity that rivals human processes. By moving from “big data” to “big insight”\, these systems point toward a new era of AI that composes knowledge across science\, engineering\, and the arts.\n\n\n2:30–2:45 pm\nBreak\n\n\n2:45–3:45 pm\nJordan Ellenberg\, UW Madison \nTitle: What does machine learning have to offer mathematics?\n\n\n3:45–4:00 pm\nBreak\n\n\n4:00–5:00 pm\nPankaj Mehta\, Boston University \nTitle: Thinking about high-dimensional biological data in the age of AI \nAbstract: The molecular biology revolution has transformed our view of living systems. Scientific explanations of biological phenomena are now synonymous with the identification of the genes and proteins. The preeminence of the molecular paradigm has only become more pronounced as new technologies allow us to make measurements at scale. Combining this wealth of data with new artificial intelligence (AI) techniques is widely viewed as the future of biology. Here\, I will discuss the promise and perils of this approach. I will focus on our unpublished work with collaborators on two fronts: (i) transformer-based models for understanding genotype-to-phenotype maps\, and (ii) LLM-based ‘foundational models’ for cellular identity\, such as TranscriptFormer\, which is trained on single-cell RNA sequencing (scRNAseq) data. While LLMs excel at capturing complex evolutionary and demographic structure in DNA sequence data\, they are much less adept at elucidating the biology of cellular identity. We show that simple parameter-free models based on linear-algebra outperform TranscriptFormer on downstream tasks related to cellular identity\, even though TranscriptFormer has nearly a billion parameters. If time permits\, I will conclude by showing how we can combine ideas from linear algebra\, bifurcation theory\, and statistical physics to classify cell fate transitions using scRNAseq data.\n\n\n\n  \nFriday\, Sep. 12\, 2025  \n\n\n\n9:00-9:45 am\nRefreshments\n\n\n9:45–10:45 am\nYiling Chen\, Harvard \nTitle: Data Reliability Scoring \nAbstract: Imagine you are trying to make a data-driven decision\, but the data at hand may be noisy\, biased\, or even strategically manipulated. Can you assess whether such a dataset is reliable—without access to ground truth?\nWe initiate the study of reliability scoring for datasets reported by potentially strategic data sources. While the true data remain unobservable\, we assume access to auxiliary observations generated by an unknown statistical process that depends on the truth. We introduce the Gram Determinant Score\, a reliability measure that evaluates how well the reported data align with the unobserved truth\, using only the reported data and the auxiliary observations. The score comes with provable guarantees: it preserves several natural reliability orderings. Experimentally\, it effectively captures data quality in settings with synthetic noise and contrastive learning embeddings.\nThis talk is based on joint work with Shi Feng\, Fang-Yi Yu\, and Paul Kattuman.\n\n\n10:45–11:00 am\nBreak\n\n\n11:00 am –12:00 pm\nYue M. Lu\, Harvard \nTitle: Nonlinear Random Matrices in High-Dimensional Estimation and Learning \nAbstract: In recent years\, new classes of structured random matrices have emerged in statistical estimation and machine learning. Understanding their spectral properties has become increasingly important\, as these matrices are closely linked to key quantities such as the training and generalization performance of large neural networks and the fundamental limits of high-dimensional signal recovery. Unlike classical random matrix ensembles\, these new matrices often involve nonlinear transformations\, introducing additional structural dependencies that pose challenges for traditional analysis techniques. \nIn this talk\, I will present a set of equivalence principles that establish asymptotic connections between various nonlinear random matrix ensembles and simpler linear models that are more tractable for analysis. I will then demonstrate how these principles can be applied to characterize the performance of kernel methods and random feature models across different scaling regimes and to provide insights into the in-context learning capabilities of attention-based Transformer networks.\n\n\n12:00–1:30 pm\nLunch break\n\n\n1:30–2:30 pm\nTrevor David Rhone\, Rensselaer Polytechnic Institute \nTitle: Accelerating the discovery of van der Waals quantum materials using AI \nAbstract: van der Waals (vdW) materials are exciting platforms for studying emergent quantum phenomena\, ranging from long-range magnetic order to topological order. A conservative estimate for the number of candidate vdW materials exceeds ~106 for monolayers and ~1012 for heterostructures. How can we accelerate the exploration of this entire space of materials? Can we design quantum materials with desirable properties\, thereby advancing innovation in science and technology? A recent study showed that artificial intelligence (AI) can be harnessed to discover new vdW Heisenberg ferromagnets based on Cr2Ge2Te6 [1]\, [2] and magnetic vdW topological insulators based on MnBi2Te4 [3]. In this talk\, we will harness AI to efficiently explore the large chemical space of vdW materials and to guide the discovery of vdW materials with desirable spin and charge properties. We will focus on crystal structures based on monolayer Cr2I6 of the form A2X6\, which are studied using density functional theory (DFT) calculations and AI. Magnetic properties\, such as the magnetic moment are determined. The formation energy is also calculated and used as a proxy for the chemical stability. We also investigate monolayers based on MnBi2Te4 of the form AB2X4 to identify novel topological materials. Further to this\, we study heterostructures based on MnBi2Te4/Sb2Te3 stacks. We show that AI\, combined with DFT\, can provide a computationally efficient means to predict the thermodynamic and magnetic properties of vdW materials [4]\,[5]. This study paves the way for the rapid discovery of chemically stable vdW quantum materials with applications in spintronics\, magnetic memory and novel quantum computing architectures.\n[1]        T. D. Rhone et al.\, “Data-driven studies of magnetic two-dimensional materials\,” Sci. Rep.\, vol. 10\, no. 1\, p. 15795\, 2020.\n[2]        Y. Xie\, G. Tritsaris\, O. Granas\, and T. Rhone\, “Data-Driven Studies of the Magnetic Anisotropy of Two-Dimensional Magnetic Materials\,” J. Phys. Chem. Lett.\, vol. 12\, no. 50\, pp. 12048–12054.\n[3]        R. Bhattarai\, P. Minch\, and T. D. Rhone\, “Investigating magnetic van der Waals materials using data-driven approaches\,” J. Mater. Chem. C\, vol. 11\, p. 5601\, 2023.\n[4]        T. D. Rhone et al.\, “Artificial Intelligence Guided Studies of van der Waals Magnets\,” Adv. Theory Simulations\, vol. 6\, no. 6\, p. 2300019\, 2023.\n[5]        P. Minch\, R. Bhattarai\, K. Choudhary\, and T. D. Rhone\, “Predicting magnetic properties of van der Waals magnets using graph neural networks\,” Phys. Rev. Mater.\, vol. 8\, no. 11\, p. 114002\, Nov. 2024.\nThis work used the Extreme Science and Engineering Discovery Environment (XSEDE)\, which is supported by National Science Foundation Grant No. ACI-1548562. This research used resources of the Argonne Leadership Computing Facility\, which is a DOE Office of Science User Facility supported under Contract No. DE-AC02-06CH11357. This material is based on work supported by the National Science Foundation CAREER award under Grant No. 2044842.\n\n\n2:30–2:45 pm\nBreak\n\n\n2:45–3:45 pm\nTess Smidt\, MIT \nTitle: Applications of Euclidean neural networks to understand and design atomistic systems \nAbstract: Atomic systems (molecules\, crystals\, proteins\, etc.) are naturally represented by a set of coordinates in 3D space labeled by atom type. This poses a challenge for machine learning due to the sensitivity of coordinates to 3D rotations\, translations\, and inversions (the symmetries of 3D Euclidean space). Euclidean symmetry-equivariant Neural Networks (E(3)NNs) are specifically designed to address this issue. They faithfully capture the symmetries of physical systems\, handle 3D geometry\, and operate on the scalar\, vector\, and tensor fields that characterize these systems. \nE(3)NNs have achieved state-of-the-art results across atomistic benchmarks\, including small-molecule property prediction\, protein-ligand binding\, force prediciton for crystals\, molecules\, and heterogeneous catalysis. By merging neural network design with group representation theory\, they provide a principled way to embed physical symmetries directly into learning. In this talk\, I will survey recent applications of E(3)NNs to materials design and highlight ongoing debates in the AI for atomistic sciences community: how to balance the incorporation of physical knowledge with the drive for engineering efficiency.\n\n\n\n 
URL:https://cmsa.fas.harvard.edu/event/bigdata_2025/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Big Data Conference,Conference,Event
ATTACH;FMTTYPE=image/jpeg:https://cmsa.fas.harvard.edu/media/Big-Data-2025_11x17.9-scaled.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250516T120000
DTEND;TZID=America/New_York:20250516T130000
DTSTAMP:20260630T142907
CREATED:20250218T161047Z
LAST-MODIFIED:20250513T152517Z
UID:10003714-1747396800-1747400400@cmsa.fas.harvard.edu
SUMMARY:Echo Chamber: RL Post-training Amplifies Behaviors Learned in Pretraining
DESCRIPTION:Member Seminar \nSpeaker: Samy Jelassi\, CMSA \nTitle: Echo Chamber: RL Post-training Amplifies Behaviors Learned in Pretraining \nAbstract: Reinforcement Learning has become a crucial step in training state-of-the-art language models such as DeepSeek-R1 for solving mathematical problems. In this talk\, I will first review the mechanisms of Reinforcement Learning fine-tuning. Then\, I will present a systematic end-to-end study of RL fine-tuning for mathematical reasoning\, training models entirely from scratch on different mixtures of fully open datasets and fine-tuning them with RL. Doing so allows us to investigate the effects of the pretraining data mixture on the behavior of RL\, and its interaction with the model size and choices of the algorithm hyperparameters. Our study reveals that RL algorithms consistently converge towards a dominant output distribution\, amplifying patterns in the pretraining data. We also find that models of different scales trained on the same data mixture will converge to distinct output distributions\, suggesting that there are scale-dependent biases in model generalization. \nThe second part of the talk is based on a joint work with Rosie Zhao\, Alex Meterez\, Cengiz Pehlevan\, Sham Kakade and Eran Malach: https://arxiv.org/abs/2504.07912 \n 
URL:https://cmsa.fas.harvard.edu/event/member-seminar-51625/
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-5.16.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250515T100000
DTEND;TZID=America/New_York:20250515T110000
DTSTAMP:20260630T142907
CREATED:20250417T165100Z
LAST-MODIFIED:20250509T175206Z
UID:10003741-1747303200-1747306800@cmsa.fas.harvard.edu
SUMMARY:Resurgence\, number theory\, and quantum mirror curves 
DESCRIPTION:Mathematical Physics and Algebraic Geometry Seminar \nSpeaker: Claudia Rella (IHES) \nTitle: Resurgence\, number theory\, and quantum mirror curves \nAbstract: Resurgence provides a powerful toolbox to access the non-perturbative sectors hidden within the divergent asymptotic series of quantum theories. Under some special assumptions\, the non-perturbative data extracted via resurgent methods possess intrinsic number-theoretic properties that are deeply rooted in the symmetries and arithmetic of the geometry underlying the quantum theory. The framework of modular resurgence aims to formalise this observation. In this talk\, after introducing the basics of modular resurgence\, I will consider the TS/ST correspondence for toric Calabi-Yau threefolds and focus on the fermionic spectral traces of quantum mirror curves. Here\, a complete realisation of the modular resurgence paradigm is found in the spectral theory of local P^2—where the bridge between non-perturbative physics and the arithmetic properties of the geometry takes the form of an exact strong-weak symmetry—and is now being generalised to all local weighted projective spaces. This talk is based on arXiv:2212.10606\, 2404.10695\, 2404.11550\, and work in progress. \n  \n  \n 
URL:https://cmsa.fas.harvard.edu/event/mathphys_51525/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Mathematical Physics and Algebraic Geometry
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Mathematical-Physics-and-Algebraic-Geometry-5.15.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250512T163000
DTEND;TZID=America/New_York:20250512T173000
DTSTAMP:20260630T142907
CREATED:20250407T140851Z
LAST-MODIFIED:20250506T191033Z
UID:10003734-1747067400-1747071000@cmsa.fas.harvard.edu
SUMMARY:Factorizations for data analysis
DESCRIPTION:Colloquium \nSpeaker: Anna Seigal\, Harvard University \nTitle: Factorizations for data analysis \nAbstract: We can find structure in data by factoring it into building blocks\, which should be interpretable for the context at hand. A classical example is principal component analysis (PCA)\, which uses the eigendecomposition of the covariance matrix to find axes of variation in a dataset. Starting from PCA\, I will discuss matrix and tensor factorizations for data analysis\, and the linear and multilinear algebra that underpins their theoretical properties. We will see examples from causal inference\, independent component analysis\, and dimensionality reduction.
URL:https://cmsa.fas.harvard.edu/event/colloquium-51225/
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-5.12.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250512T150000
DTEND;TZID=America/New_York:20250512T160000
DTSTAMP:20260630T142907
CREATED:20250226T174007Z
LAST-MODIFIED:20250605T134144Z
UID:10003716-1747062000-1747065600@cmsa.fas.harvard.edu
SUMMARY:An index for 2d invertible phases of quantum many-body systems
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Nikita Sopenko\, IAS \nTitle: An index for 2d invertible phases of quantum many-body systems
URL:https://cmsa.fas.harvard.edu/event/qft_51225/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QFT-and-Physical-Mathematics-5.12.25-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250509T120000
DTEND;TZID=America/New_York:20250509T130000
DTSTAMP:20260630T142907
CREATED:20241211T195446Z
LAST-MODIFIED:20250506T153832Z
UID:10003649-1746792000-1746795600@cmsa.fas.harvard.edu
SUMMARY:Asset pricing with heterogeneous agents
DESCRIPTION:Member Seminar \nSpeaker: Sergiy Verstyuk\, Harvard CMSA \nTitle: Asset pricing with heterogeneous agents \nAbstract: This talk will introduce the basics of continuous-time finance\, discuss important existing theories and models\, as well as present some new asset pricing results in a setting with many heterogeneous investors. (Joint work with Puskar Mondal.) \n 
URL:https://cmsa.fas.harvard.edu/event/member-seminar-5925/
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-5.9.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250505T163000
DTEND;TZID=America/New_York:20250505T173000
DTSTAMP:20260630T142907
CREATED:20250407T140808Z
LAST-MODIFIED:20250501T134436Z
UID:10003733-1746462600-1746466200@cmsa.fas.harvard.edu
SUMMARY:Thinking Outside the Ballot Box
DESCRIPTION:Colloquium \nSpeaker: Ariel Procaccia\, Harvard University \nTitle: Thinking Outside the Ballot Box \nAbstract: How should one design unprecedented democratic processes capable of handling enormous sets of alternatives like all possible policies\, bills\, or statements? I argue that this challenge can be addressed through a framework called generative social choice\, which fuses the rigor of social choice theory with the flexibility and power of large language models. I then explore an application of generative social choice to the problem of identifying a proportionally representative slate of opinion statements. This includes a discussion of desired properties\, an algorithm that provably achieves them\, an implementation using GPT\, and insights from an end-to-end pilot. By providing guarantees\, generative social choice could alleviate concerns about AI-driven democratic innovation and help unlock its potential.
URL:https://cmsa.fas.harvard.edu/event/colloquium-5525/
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-5.5.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250505T150000
DTEND;TZID=America/New_York:20250505T160000
DTSTAMP:20260630T142907
CREATED:20250226T173940Z
LAST-MODIFIED:20250226T173940Z
UID:10003715-1746457200-1746460800@cmsa.fas.harvard.edu
SUMMARY:Quantum Field Theory and Physical Mathematics
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar
URL:https://cmsa.fas.harvard.edu/event/qft_5525/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250502T120000
DTEND;TZID=America/New_York:20250502T130000
DTSTAMP:20260630T142907
CREATED:20241211T195435Z
LAST-MODIFIED:20250428T151202Z
UID:10003650-1746187200-1746190800@cmsa.fas.harvard.edu
SUMMARY:Incentives for data sharing in federated learning
DESCRIPTION:Member Seminar \nSpeaker: Han Shao\, Harvard CMSA \nTitle: Incentives for data sharing in federated learning \nAbstract: Federated learning has recently emerged as a powerful approach for enabling collaboration across large populations of learning agents. However\, agents may have incentives to defect from the collaboration—that is\, to withdraw or contribute less data than expected—due to the costs of data curation and privacy concerns. This raises several key questions: What happens when agents defect\, and how can we prevent such defections? \n 
URL:https://cmsa.fas.harvard.edu/event/member-seminar-5225/
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-5.2.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250501T100000
DTEND;TZID=America/New_York:20250501T110000
DTSTAMP:20260630T142907
CREATED:20250128T172012Z
LAST-MODIFIED:20250428T143252Z
UID:10003681-1746093600-1746097200@cmsa.fas.harvard.edu
SUMMARY:From superspace to twisted supergravity
DESCRIPTION:Mathematical Physics and Algebraic Geometry Seminar \nSpeaker: Fabian Hahner\, University of Washington \nTitle: From superspace to twisted supergravity \nAbstract: In this talk\, I will present a geometric perspective on the pure spinor superfield formalism\, which proves fruitful for studying twisted supergravity. For eleven-dimensional supergravity\, we use this technique to construct the full interacting theory together with all its twists in a uniform and geometric way as homotopy Poisson–Chern–Simons theories. In addition to simplifying the computation of twists immensely\, this also provides fresh insights into the supergeometric origin of supergravity. Building on these ideas\, we further construct local dg Lie algebras that recover conformal supergravity multiplets and their twists in terms of a geometric moduli problem on superspace. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/mathphys_5125/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Mathematical Physics and Algebraic Geometry
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Mathematical-Physics-and-Algebraic-Geometry-5.1.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250428T163000
DTEND;TZID=America/New_York:20250428T173000
DTSTAMP:20260630T142907
CREATED:20241209T171137Z
LAST-MODIFIED:20250423T174326Z
UID:10003637-1745857800-1745861400@cmsa.fas.harvard.edu
SUMMARY:Bass-Note Spectra of locally uniform geometries
DESCRIPTION:Colloquium \nSpeaker: Peter Sarnak\, IAS & Princeton University \nTitle: Bass-Note Spectra of locally uniform geometries \nAbstract: We formulate and report on the problem of the Bass-Note Spectrum of an invariant operator as one varies over locally uniform geometries. In the Euclidean setting this recasts classical problems of Mahler from the geometry of numbers in a new light. For certain operators homogeneous dynamics can be used decisively. In the non-Euclidean setting of hyperbolic manifolds we review some recent developments using the conformal bootstrap method and of random covers to study the Bass-Note spectra. We highlight the theme and impact of rigidity.
URL:https://cmsa.fas.harvard.edu/event/colloquium-42825/
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-4.28.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250424T100000
DTEND;TZID=America/New_York:20250424T110000
DTSTAMP:20260630T142907
CREATED:20250128T191347Z
LAST-MODIFIED:20250421T140604Z
UID:10003686-1745488800-1745492400@cmsa.fas.harvard.edu
SUMMARY:Mass gap in AdS space
DESCRIPTION:Mathematical Physics and Algebraic Geometry Seminar \nSpeaker: Ziming Ji\, Northeastern University \nTitle: Mass gap in AdS space \nAbstract: AdS space can be used as an IR regulator of QFT. The asymptotic conformal boundary in AdS space provides rich\, unique observables. We study asymptotic free theories in two-dimensional AdS space. By changing the AdS curvature scale \Lambda L\, we observe boundary signals of quantum phase transitions where mass gaps are dynamically generated in the bulk. We also utilize supersymmetry to study gauge theories in AdS4. We argue a connection between the AdS partition function and the prepotential and use the F-maximization of the Nekrasov partition function to study supersymmetric boundary conditions and its connection to the Seiberg-Witten theory. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/mathphys_42425/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Mathematical Physics and Algebraic Geometry
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Mathematical-Physics-and-Algebraic-Geometry-4.24.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250423T140000
DTEND;TZID=America/New_York:20250423T150000
DTSTAMP:20260630T142907
CREATED:20250128T214818Z
LAST-MODIFIED:20250311T184354Z
UID:10003709-1745416800-1745420400@cmsa.fas.harvard.edu
SUMMARY:Machine learning for analytic calculations in theoretical physics
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Matthias Wilhelm (University of Southern Denmark) \nTitle: Machine learning for analytic calculations in theoretical physics \nAbstract: In this talk\, we will present recent progress on applying machine-learning techniques to improve calculations in theoretical physics\, in which we desire exact and analytic results. One example are so-called integration-by-parts reductions of Feynman integrals\, which pose a frequent bottleneck in state-of-the-art calculations in theoretical particle and gravitational-wave physics. These reductions rely on heuristic approaches for selecting a finite set of linear equations to solve\, and the quality of the heuristics heavily influences the performance. In this talk\, we investigate the use of machine-learning techniques to find improved heuristics. We use funsearch\, a genetic programming variant based on code generation by a Large Language Model\, in order to explore possible approaches\, then use strongly typed genetic programming to zero in on useful solutions. Both approaches manage to re-discover the state-of-the-art heuristics recently incorporated into integration-by-parts solvers\, and in one example find a small advance on this state of the art.
URL:https://cmsa.fas.harvard.edu/event/newtech_42325/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-4.23.2025.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250421T163000
DTEND;TZID=America/New_York:20250421T173000
DTSTAMP:20260630T142907
CREATED:20241209T163847Z
LAST-MODIFIED:20250418T142045Z
UID:10003636-1745253000-1745256600@cmsa.fas.harvard.edu
SUMMARY:Modeling the emergence of complex cortical structure from simple precursors in the brain: maps\, hierarchies\, and modules
DESCRIPTION:Colloquium \nSpeaker: Ila Fiete\, MIT \nTitle: Modeling the emergence of complex cortical structure from simple precursors in the brain: maps\, hierarchies\, and modules \nAbstract: Modular and hierarchical structures are ubiquitous in the brain. Two distinct hypotheses for such morphogenesis involve genetic specification (the positional information hypothesis) or spontaneous structure emergence from symmetry breaking (the pattern formation hypothesis). Indeed\, there is rich evidence supporting both hypotheses in different systems\, and more recently evidence that both systems might interact\, for instance with genetic specification providing an initial but relatively low-information scaffold of positional guidance and pattern formation constructing sharper structures by bootstrapping from this guidance. In this talk\, I will consider the emergence of two systems in the brain: the visual processing hierarchy with topographic structure\, and a modular cognitive circuit consisting of functionally independent grid cell networks that compute spatial location from velocity cues as animals move and navigate the world. I will describe how simple activity-driven growth and competition rules can lead to the emergence of topographically ordered sensory processing hierarchies\, and how genetically specified smooth gradients with purely local recurrent interactions on two scales can lead to global module emergence. In sum\, simple growth rules\, local interactions and smooth gradients can interact to produce rich emergent order on multiple scales in the form of maps\, modules\, and hierarchies\, with predictions that bridge scales from genes to connectivity to function.
URL:https://cmsa.fas.harvard.edu/event/colloquium-42125/
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-4.21.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250418T120000
DTEND;TZID=America/New_York:20250418T130000
DTSTAMP:20260630T142907
CREATED:20241211T195316Z
LAST-MODIFIED:20250218T160819Z
UID:10003647-1744977600-1744981200@cmsa.fas.harvard.edu
SUMMARY:Member Seminar
DESCRIPTION:Member Seminar \nSpeaker: Han Shao \n 
URL:https://cmsa.fas.harvard.edu/event/member-seminar-41825/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Member Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250414T163000
DTEND;TZID=America/New_York:20250414T173000
DTSTAMP:20260630T142907
CREATED:20241209T163821Z
LAST-MODIFIED:20250410T204704Z
UID:10003635-1744648200-1744651800@cmsa.fas.harvard.edu
SUMMARY:Quantum K-theory at roots of unity
DESCRIPTION:Colloquium \nSpeaker: Andrey Smirnov\, University of North Carolina at Chapel Hill \nTitle: Quantum K-theory at roots of unity \nAbstract: In this talk\, I will discuss a version of quantum K-theory introduced by A.Okounkov\, which can be defined through quasimap counts. In this framework\, the quantum K-theory ring is obtained as a specialization of the equivariant quasimap count at $q=1$\, where $q$ is the equivariant parameter associated with the torus action on the source of the quasimaps. A related\, but less explored\, structure emerges when $q$ is specialized at the roots of unity. I will outline the key ideas behind this construction and its implications. As an application\, I’ll also describe the spectrum of $p$-curvature for the quantum connection\, which offers a new proof of a recent result by P.Etingof and A.Varchenko. This talk is based on joint work with P. Koroteev.
URL:https://cmsa.fas.harvard.edu/event/colloquium-41425/
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-4.14.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250411T120000
DTEND;TZID=America/New_York:20250411T130000
DTSTAMP:20260630T142907
CREATED:20241211T195247Z
LAST-MODIFIED:20250407T150951Z
UID:10003646-1744372800-1744376400@cmsa.fas.harvard.edu
SUMMARY:Homological Invariants in Translation-Invariant Pauli Stabilizer Codes
DESCRIPTION:Member Seminar \nSpeaker: Bowen Yang \nTitle: Homological Invariants in Translation-Invariant Pauli Stabilizer Codes \nAbstract: Pauli stabilizer codes serve as foundational models in quantum error correction and the study of exotic quantum phases. In this talk\, we explore the application of homological methods to translationally invariant Pauli stabilizer codes with qudits of varying dimensions. We introduce a series of invariants\, termed charge modules\, and delve into their properties and physical interpretations. A key focus is on codes whose charge modules exhibit zero Krull dimension\, a condition indicative of the mobility of excitations. Notably\, we demonstrate that this condition is universally met in two-dimensional codes with a unique ground state in infinite volume\, extending prior findings beyond the realm of uniform\, prime qudit dimensions. For systems where all excitations are mobile\, we establish the existence of p-dimensional excitations and associated (D−p−1)-form symmetries corresponding to each element of the p-th charge module. Additionally\, we define a braiding pairing between charge modules in complementary degrees.
URL:https://cmsa.fas.harvard.edu/event/member-seminar-41125/
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-4.11.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250409T140000
DTEND;TZID=America/New_York:20250409T150000
DTSTAMP:20260630T142907
CREATED:20250128T214458Z
LAST-MODIFIED:20250410T150618Z
UID:10003707-1744207200-1744210800@cmsa.fas.harvard.edu
SUMMARY:Can Transformers Do Enumerative Geometry?
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Baran Hashemi\, Technical University of Munich \nTitle: Can Transformers Do Enumerative Geometry? \nAbstract: How can Transformers model and learn enumerative geometry? What is a systematic procedure for using Transformers in abductive knowledge discovery within a mathematician-machine collaboration? In this work\, we introduce a Neural Enumerative Reasoning model for computation of ψ-class intersection numbers on the moduli space of curves. By reformulating the problem as a continuous optimization task\, we compute intersection numbers across a wide value range from 10e-45 to 10e45. To capture the recursive nature inherent in these intersection numbers\, we propose the Dynamic Range Activator (DRA)\, a new activation function that enhances the Transformer’s ability to model recursive patterns and handle severe heteroscedasticity. Given precision requirements for computing the intersections\, we quantify the uncertainty of the predictions using Conformal Prediction with a dynamic sliding window adaptive to the partitions of equivalent number of marked points. Beyond simply computing intersection numbers\, we explore the enumerative “world-model” of Transformers. Our interpretability analysis reveals that the network is implicitly modeling the Virasoro constraints in a purely data-driven manner. Moreover\, through abductive hypothesis testing\, probing\, and causal inference\, we uncover evidence of an emergent internal representation of the large-genus asymptotic of ψ-class intersection numbers. This opens up new possibilities in inferring asymptotic closed-form expressions directly from limited amount of data. \nThis talk is based on https://openreview.net/pdf?id=4X9RpKH4Ls. \n 
URL:https://cmsa.fas.harvard.edu/event/newtech_4925/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-4.9.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250408T090000
DTEND;TZID=America/New_York:20250408T103000
DTSTAMP:20260630T142907
CREATED:20250331T204029Z
LAST-MODIFIED:20250409T143732Z
UID:10003731-1744102800-1744108200@cmsa.fas.harvard.edu
SUMMARY:CMSA/Tsinghua Math-Science Literature Lecture: Scott Sheffield (MIT): Yang-Mills theory and random surfaces
DESCRIPTION:CMSA/Tsinghua Math-Science Literature Lecture \nDate: April 8\, 2025 \nTime: 9:00 – 10:30 am ET \nLocation: CMSA G10\, 20 Garden Street\, Cambridge MA & via Zoom \nSpeaker: Scott Sheffield (MIT) \nTitle: Yang-Mills theory and random surfaces \nAbstract: The Clay Institute famously offered one million dollars to anyone who could mathematically construct and understand a certain continuum version of “Yang-Mills gauge theory.” This theory is the basis of the standard model of physics\, and the heart of the problem is to understand the so-called “Wilson loop expectations.” Following recent work with Sky Cao and Minjae Park\, I will explain how the “Wilson loop expectations” in a lattice Yang-Mills model are equivalent to “insertion costs” of loops in a related random-closed-surface-ensemble model. In a sense\, these results allow us to convert one famously hard problem into another presumably hard problem. But the new problem is all about random surfaces and random permutations\, and it has a lot of relationships with and similarities to other problems we understand (think domino tilings\, random planar maps\, Young tableaux and symmetric group representation theory\, and the Weingarten calculus). It gives us some intuition for *why* certain things should be true like the “area law” or “exponential correlation decay” (what physicists call “quark confinement” or “mass gap”) even if we can’t prove all of them yet. \n\nBeginning in Spring 2020\, the CMSA began hosting a lecture series on literature in the mathematical sciences\, with a focus on significant developments in mathematics that have influenced the discipline\, and the lifetime accomplishments of significant scholars.
URL:https://cmsa.fas.harvard.edu/event/mathscilit2025_ss/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Math Science Literature Lecture Series,Public Lecture,Special Lectures
ATTACH;FMTTYPE=image/jpeg:https://cmsa.fas.harvard.edu/media/Mathlit_Sheffield_11x17-2.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250407T163000
DTEND;TZID=America/New_York:20250407T173000
DTSTAMP:20260630T142907
CREATED:20241209T163727Z
LAST-MODIFIED:20250401T191454Z
UID:10003634-1744043400-1744047000@cmsa.fas.harvard.edu
SUMMARY:3-d Mirror Symmetry
DESCRIPTION:Colloquium \nSpeaker: Ben Webster\, University of Waterloo & Perimeter Institute \nTitle: 3-d Mirror Symmetry \nAbstract: I’ll give an introduction (or update\, for those who’ve been introduced) to 3d mirror symmetry from the perspective of a mathematician. \n 
URL:https://cmsa.fas.harvard.edu/event/colloquium-4725/
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-4.7.2025.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250407T150000
DTEND;TZID=America/New_York:20250407T160000
DTSTAMP:20260630T142907
CREATED:20250128T192454Z
LAST-MODIFIED:20250331T184600Z
UID:10003694-1744038000-1744041600@cmsa.fas.harvard.edu
SUMMARY:Quantum Field Theory and Physical Mathematics
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Matthew Yu (Oxford) \nTitle: A new tangential structure for type IIA string theory \nAbstract: The Green-Schwarz anomaly cancellation condition says that the target space of heterotic string theory must come with a string structure for the theory to be consistent. In this talk we discuss a new tangential structure called string^h\, first introduced by Devalapurkar\, as a spin^c analogue of string. Approximating the correct tangential structure of string theory has many implications\, primarily is the Swampland program via the cobordism conjecture of Mcnamara and Vafa. We will show that the spectrum of string^h has the notable property that it orients tmf_1(n)\, just like how the spectrum of string orients tmf\, by the work of Ando-Hopkins-Rezk. Finally we will show that the anomaly condition of the partition function of M-theory\, studied by Diaconescu-Moore-Witten is implied by a string^h structure on the target space of type IIA\, in parallel to the Green-Schwarz anomaly for heterotic string theory\, and discuss applications for anomaly cancellation.
URL:https://cmsa.fas.harvard.edu/event/qft_4725/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QFT-and-Physical-Mathematics-4.7.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250404T120000
DTEND;TZID=America/New_York:20250404T130000
DTSTAMP:20260630T142907
CREATED:20241211T195214Z
LAST-MODIFIED:20250328T164025Z
UID:10003645-1743768000-1743771600@cmsa.fas.harvard.edu
SUMMARY:Learning diffusion models in high-dimensions
DESCRIPTION:Member Seminar \nSpeaker: Hugo Cui \nTitle: Learning diffusion models in high-dimensions \nAbstract: We consider the problem of learning a generative model parametrized by a two-layer auto-encoder\, and trained with online stochastic gradient descent\, to sample from a high-dimensional data distribution with an underlying low-dimensional structure. We provide a tight asymptotic characterization of low-dimensional projections of the resulting generated density\, and evidence how mode(l) collapse can arise.  On the other hand\, we discuss how in a case where the architectural bias is suited to the target density\, these simple models can efficiently learn to sample from a binary Gaussian mixture target distribution. \n 
URL:https://cmsa.fas.harvard.edu/event/member-seminar-4425/
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-4.4.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250403T100000
DTEND;TZID=America/New_York:20250403T110000
DTSTAMP:20260630T142907
CREATED:20250128T172140Z
LAST-MODIFIED:20250331T191842Z
UID:10003683-1743674400-1743678000@cmsa.fas.harvard.edu
SUMMARY:(Strictly) Non-minimal Elliptic Threefolds and the Distance Conjecture
DESCRIPTION:Mathematical Physics and Algebraic Geometry Seminar \nSpeaker: Rafael Álvarez García (Harvard University) \nTitle: (Strictly) Non-minimal Elliptic Threefolds and the Distance Conjecture \nAbstract: We analyze infinite-distance limits in the complex structure moduli space of six-dimensional F-theory\, providing an algebro-geometric classification and a physical interpretation. From the point of view of the Swampland Program\, the motivation is to understand the fate of open-moduli infinite-distance limits in relation with the Distance Conjecture. From an F-theory perspective\, the infinite-distance limits correspond to degenerations of elliptic threefolds leading to non-minimal singularities in codimension one and higher. We show how such non-crepant singularities can be removed by a systematic sequence of blow-ups of the bases of the infinite-distance degenerations\, making their central fibers a union of log Calabi-Yau spaces glued together along their boundaries. We interpret said central fibers as either the endpoints of decompactification limits with six-dimensional defects or as emergent string limits\, providing further evidence for the Emergent String Conjecture. Degenerations leading to strictly non-minimal singularities can correspond both to finite-distance and infinite-distance limits in the open moduli space. We analyze the chain of modifications and base changes necessary to unambiguously determine the fate of such families of F-theory models. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/mathphys_4325/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Mathematical Physics and Algebraic Geometry
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Mathematical-Physics-and-Algebraic-Geometry-4.3.2025-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250402T140000
DTEND;TZID=America/New_York:20250402T150000
DTSTAMP:20260630T142907
CREATED:20250128T214417Z
LAST-MODIFIED:20250403T144343Z
UID:10003706-1743602400-1743606000@cmsa.fas.harvard.edu
SUMMARY:Learning Dynamical Transport without Data
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Michael Albergo (Harvard) \nTitle: Learning Dynamical Transport without Data \nAbstract: Algorithms based on dynamical transport of measure\, such as score-based diffusion models\, have resulted in great progress in the field of generative modeling. However\, these algorithms rely on access to an abundance of data from the target distribution. A complementary problem to this is learning to generate samples from a target distribution when only given query access to the unnormalized log-likelihood or energy function associated to it\, with myriad application in statistical physics\, chemistry\, and Bayesian inference. I will present an algorithm based on dynamical transport to sample from a target distribution in this context\, which can be seen as an augmentation of annealed importance sampling and sequential Monte Carlo. Time permitting\, I will also discuss how to generalize these ideas to dynamics of discrete distributions. This is joint work with Eric Vanden-Eijnden\, Peter Holderrieth\, and Tommi Jaakkola. \n 
URL:https://cmsa.fas.harvard.edu/event/newtech_4225/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-4.2.2025.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250331T150000
DTEND;TZID=America/New_York:20250331T160000
DTSTAMP:20260630T142907
CREATED:20250128T192422Z
LAST-MODIFIED:20250326T181346Z
UID:10003693-1743433200-1743436800@cmsa.fas.harvard.edu
SUMMARY:Homotopical Methods for Free and Interacting Fermionic SPTs
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Cameron Krulewski\, MIT \nTitle: Homotopical Methods for Free and Interacting Fermionic SPTs \nAbstract: We develop and compute homotopical “free-to-interacting maps” to compare classifications of fermionic symmetry-protected topological phases (SPTs)\, determining when such phases are stable under interactions or\, alternatively\, interaction-enabled. Generalizing work of Freed-Hopkins\, we construct maps from K-theory to Anderson-dual spin bordism in two new situations: for weak phases\, which are SPTs protected by discrete translation symmetry\, and for the “Bott spiral” studied by Queiroz-Khalaf-Stern\, who observed that the tenfold way classification of free theories breaks down to a large 2-torsion interacting classification. Along the way\, we employ T-duality\, generalizations of the spin orientation of KO-theory\, and the Adams spectral sequence. \nThis talk is based on joint work with Omar Antolín Camarena\, Arun Debray\, Natalia Pacheco-Tallaj\, Daniel Sheinbaum\, and Luuk Stehouwer.
URL:https://cmsa.fas.harvard.edu/event/qft_33125/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QFT-and-Physical-Mathematics-3.31.25.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250324T163000
DTEND;TZID=America/New_York:20250324T173000
DTSTAMP:20260630T142907
CREATED:20241209T163216Z
LAST-MODIFIED:20250321T163829Z
UID:10003631-1742833800-1742837400@cmsa.fas.harvard.edu
SUMMARY:The Toda Lattice as a Soliton Gas
DESCRIPTION:Colloquium \nSpeaker: Amol Aggarwal\, Columbia University \nTitle: The Toda Lattice as a Soliton Gas \nAbstract: A basic tenet of integrable systems is that\, under sufficiently irregular initial data\, they can be thought of as dense collections of many solitons\, or “soliton gases.” In this talk we focus on the Toda lattice\, which is an archetypal example of an integrable Hamiltonian dynamical system. We explain how the system\, under certain random initial data\, can be interpreted through solitons\, and provide a framework for studying how these solitons asymptotically evolve in time. The arguments use ideas from random matrix theory\, particularly the analysis of Lyapunov exponents governing the decay rates of eigenvectors of random tridiagonal matrices.
URL:https://cmsa.fas.harvard.edu/event/colloquium-32425/
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-3.24.2025.docx.final_.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20250324T150000
DTEND;TZID=America/New_York:20250324T160000
DTSTAMP:20260630T142907
CREATED:20250128T192400Z
LAST-MODIFIED:20250318T141044Z
UID:10003692-1742828400-1742832000@cmsa.fas.harvard.edu
SUMMARY:The Andersen-Kashaev volume conjecture for FAMED geometric triangulations  
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Ka Ho Wong (Yale) \nTitle: The Andersen-Kashaev volume conjecture for FAMED geometric triangulations \nAbstract: In the early 2010s\, Andersen and Kashaev defined a TQFT based on quantum Teichmuller theory. In particular\, they define a partition function for every ordered ideal triangulation of hyperbolic knot complement in $\mathbb{S}^3$ equipped with an angle structure. The Andersen-Kashaev volume conjecture suggests that the partition function can be expressed in terms of a Jones function of the knot which\, in its semi-classical limit\, decay exponentially with decay rate the hyperbolic volume of the knot complement. In this talk\, we will introduce a purely combinatorial condition on triangulations which\, together with the geometricity of the triangulations\, imply the Andersen-Kashaev volume conjecture and its generalization. This talk is based on the joint work with Fathi Ben Aribi.
URL:https://cmsa.fas.harvard.edu/event/qft_32425/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Quantum Field Theory and Physical Mathematics
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