During the 2022-23 academic year, the CMSA will host a seminar on Swampland, organized by Max Wiesner and Cumrun Vafa. This seminar will take place biweekly on Mondays at 11:00 am - 12:00 pm (Boston time). The meetings will take place in Room G10 at the CMSA, 20 Garden Street, Cambridge MA 02138 and virtually via Zoom. To learn how to attend, please subscribe here. Talks will be posted on the Swampland Seminars YouTube channel. The schedule will be updated as talks are confirmed.  

CMSA COVID-19 Policies

  • December 05, 2022 11:00 AM
Speaker: Markus Dierigl
Title: IIB Explored &#; Dualities, Bordisms, and the Swampland
Venue: Jefferson 356

Swampland Seminar Location: Jefferson Physical Laboratory, Seminar room J356 Speaker: Markus Dierigl (LMU Munich) Title: IIB Explored – Dualities, Bordisms, and the Swampland Abstract: In this talk I will discuss the application of the Cobordism Conjecture to type IIB supergravity with non-trivial duality bundle. Calculating the relevant bordism groups we find that they are highly non-trivial and would predict the presence of various global symmetries in the underlying theory. Since quantum gravity theories do not allow for global symmetries, we discuss which defects need to be included to break them completely. Interestingly, we find many backgrounds that are well-known in the F-theory literature, such as [p,q]-7-branes, non-Higgsable clusters, as well as S-folds and their generalizations to higher codimensions. Further including…

  • November 15, 2022 11:00 AM
Speaker: Alvaro Herraez
Title: The Emergence Proposal in Quantum Gravity and the Species Scale
Venue: CMSA Room G10

Swampland Seminar Speaker: Alvaro Herraez (Saclay) Title: The Emergence Proposal in Quantum Gravity and the Species Scale Abstract: The Emergence Proposal claims that in Quantum Gravity the kinetic terms of the fields in the IR emerge from integrating out (infinite) towers of particles up to the QG cutoff. After introducing this proposal in the context of the Swampland Program, I will explain why it is natural to identify this QG cutoff with the Species Scale, motivating it by direct computation in the presence of the relevant towers. Then, I will present evidence for this proposal by directly studying how it is realized in different string theory setups, where the kinetic terms of scalars, p-forms and even scalar potentials can be shown…

  • November 07, 2022 11:00 AM
Speaker: Fernando Marchesano
Title: EFT strings and emergence
Venue: CMSA Room G10

Swampland Seminar Speaker: Fernando Marchesano (IFT Madrid) Title: EFT strings and emergence Abstract: We revisit the Emergence Proposal in 4d N=2 vector multiplet sectors that arise from  type II string Calabi-Yau compactifications, with emphasis on the role of axionic fundamental strings, or EFT strings. We focus on large-volume type IIA compactifications, where EFT strings arise from NS5-branes wrapping internal four-cycles, and consider a set of infinite-distance moduli-space limits that can be classified in terms of a scaling weight w=1,2,3. It has been shown before how one-loop threshold effects of an infinite tower of BPS particles made up of D2/D0-branes generate the asymptotic behaviour of  the gauge kinetic functions along limits with $w=3$. We extend this result to w=2 limits, by taking…

  • October 24, 2022 11:00 AM
Speaker: Paul-Konstantin Oehlmann
Title: Anomalies of Discrete Gauge Symmetries and their Cancellation in D F-theory
Venue: CMSA Room G10

Swampland Seminar Speaker: Paul-Konstantin Oehlmann(Northeastern) Title: Anomalies of Discrete Gauge Symmetries and their Cancellation in 6D F-theory Abstract: We consider 6D SUGRAs with a discrete gauge group G, engineered via F-theory compactifications on genus-one fibered threefolds. We argue that group G suffers from Dai-Freed anomalies that can be canceled via a discrete Green-Schwarz mechanism. We comment on the ambiguity to assign this GS term in the 7D Anomaly theory which leads to choices that are not all compatible with F-theory. In F-theory we then deduce this Anomaly coefficient explicitly by computing the elliptic genera of the non-critical strings that couple to the 6D two-form fields: Their 2D worldsheet theories inherits a G Flavor symmetries whose t’Hooft anomaly cancels the 6D Dai-Freed anomaly in the…

  • October 11, 2022 11:00 AM
Speaker: Aasmund Folkestad
Title: The Penrose Inequality as a Constraint on Low Energy Quantum Gravity
Venue: CMSA Room G10

Swampland Seminar Speaker: Aasmund Folkestad (MIT) Title: The Penrose Inequality as a Constraint on Low Energy Quantum Gravity Abstract: In this talk, I argue that the Penrose inequality (PI) can be used to constrain low energy theories compatible AdS/CFT, and possibly also quantum gravity in flat space. Focusing on AdS/CFT, it is shown that the PI can be violated for minimally coupled scalar fields, and I produce exclusion plots on couplings that respect the PI. I also present numerical evidence that top-down scalar theories and supersymmetric theories respect the PI. Finally, similar to the Breitenlohner-Freedman bound, I give a necessary condition for the stability AdS that constrains coupling constants (beyond the scalar mass).

  • September 19, 2022 11:00 AM
Speaker: Samir Mathur
Title: The story of the information paradox
Venue: CMSA Room G10

Swampland Seminar Speaker: Samir Mathur (Ohio State) Title: The story of the information paradox Abstract:  In 1975 Hawking argued that black hole evaporation would lead to a loss of unitarity in quantum theory.  The small corrections theorem made Hawking’s argument into a precise statement: if semiclassical physics hold to leading order in any gently curved region of spacetime, then there can be no resolution to the paradox. In string theory, whenever people have been able to construct microstates explicutly, the states turned out to be horizon sized objects (fuzzballs) with no horizon; such a structure of microstates resolves the information paradox since their is no pair creation at a vacuum horizon. There have been a set of parallel attempts to…

  • May 09, 2022 01:00 PM
Speaker: Georges Obie
Title: Inflation and light Dark Matter constraints from the Swampland
Venue: Virtual

Abstract: I will explore the interplay between Swampland conjectures and models of inflation and light Dark Matter. To that end, I will briefly review the weak gravity conjecture (WGC) and the related Festina Lente (FL) bound. These have implications for light darkly and milli-charged particles and can disfavor a large portion of parameter space. The FL bound also implies strong restrictions on the field content of our universe during inflation and presents an opportunity for inflationary model building. At the same time, it rules out some popular models like chromo-natural inflation and gauge-flation. Finally, I will review  another Swampland conjecture related to Stückelberg photon masses and discuss its implications for astro-particle physics.

  • April 18, 2022 01:00 PM
Speaker: José Calderón
Title: Swampland Seminar
Venue: Virtual

Open mic Swampland Discussion Topic: Cobordism

  • April 11, 2022 10:00 AM
Speaker: Timm Wrase and Eduardo Gonzalo (Lehigh)
Title: Type IIB flux compactifications with $h^{,}=$
Venue: virtual

Abstract: We revisit type IIB flux compactification that are mirror dual to type IIA on rigid Calabi-Yau manifolds. We find a variety of interesting new solutions, like fully stabilized Minkowski vacua and infinite families of AdS$_4$ solutions with arbitrarily large numbers of spacetime filling D3 branes. We discuss how these solutions fit into the web of swampland conjectures.

  • April 04, 2022 10:00 AM
Speaker: Simon Caron-Huot (McGill University) and Julio Parra (Caltech)
Title: Causality constraints on corrections to Einstein gravity
Venue: virtual

Swampland Seminar Speakers: Simon Caron-Huot (McGill University) and Julio Parra (Caltech) Title: Causality constraints on corrections to Einstein gravity Abstract: We study constraints from causality and unitarity on 2→2 graviton scattering in four-dimensional weakly-coupled effective field theories. Together, causality and unitarity imply dispersion relations that connect low-energy observables to high-energy data. Using such dispersion relations, we derive two-sided bounds on gravitational Wilson coefficients in terms of the mass M of new higher-spin states. Our bounds imply that gravitational interactions must shut off uniformly in the limit G→0, and prove the scaling with M expected from dimensional analysis (up to an infrared logarithm). We speculate that causality, together with the non-observation of gravitationally-coupled higher-spin states at colliders, severely restricts modifications to Einstein gravity that could be probed by experiments in the near future.

  • March 28, 2022 01:00 PM
Speaker: Fernando Quevedo
Title: On renormalisation group induced moduli stabilisation and brane-antibrane inflation
Venue: Virtual

Abstract: A proposal to use the renormalisation group to address moduli stabilisation in IIB string perturbation theory will be described. We revisit brane-antibrane inflation combining this proposal with non-linearly realised supersymmetry.

  • March 21, 2022 01:00 PM
Speaker: Patrick Draper (Univ. of Illinois) and Alvaro Herraez (IPhT Saclay)
Title: Swampland Seminar
Venue: Virtual

Open Mic Discussion Topic: Entropy bounds (species bound, Bekenstein bound, CKN bound, and the like)

  • March 07, 2022 10:00 AM
Speaker: Fernando Marchesano (UAM-CSIC, Madrid) and Max Wiesner (Harvard CMSA)
Title: d strings at strong coupling
Venue: virtual

Speakers: Fernando Marchesano (UAM-CSIC, Madrid)  and Max Wiesner (Harvard CMSA) Title: 4d strings at strong coupling As usual, the format will be 45 min talk + 30 min discussion, to encourage participation from the audience. Looking forward to seeing you there!

  • February 28, 2022 01:00 PM
Speaker: Tom Rudelius
Title: Generalized Global Symmetries and the Weak Gravity Conjecture
Venue: Virtual
  • February 07, 2022 01:00 PM
Speaker: Du Pei
Title: Holomorphic CFTs and topological modular forms
Venue: Virtual

Abstract: The theory of topological modular forms leads to many interesting constraints and predictions for two-dimensional quantum field theories, and some of them might have interesting implications for the swampland program. In this talk, I will show that a conjecture by Segal, Stolz and Teichner requires the constant term of the partition function of a bosonic holomorphic CFTs to be divisible by specific integers determined by the central charge. We verify this constraint in large classes of physical examples, and rule out the existence of an infinite set of “extremal CFTs”, including those with central charges c = 48, 72, 96 and 120.

  • January 31, 2022 01:00 PM
Speaker: Rafael Álvarez-García
Title: Membrane Limits in Quantum Gravity
Venue: Virtual
  • December 06, 2021 01:00 PM
Speaker: Lars Aalsma
Title: Extremal Black Hole Corrections from Iyer-Wald
Venue: Virtual

Abstract: Extremal black holes play a key role in our understanding of various swampland conjectures and in particular the WGC. The mild form of the WGC states that higher-derivative corrections should decrease the mass of extremal black holes at fixed charge. Whether or not this conjecture is satisfied depends on the sign of the combination of Wilson coefficients that control corrections to extremality. Typically, corrections to extremality need to be computed on a case-by-case basis, but in this talk I will present a universal derivation of extremal black hole corrections using the Iyer-Wald formalism. This leads to a formula that expresses general corrections to the extremality bound in terms of the stress tensor of the perturbations under consideration, clarifying the…

  • November 29, 2021 01:00 PM
Speaker: Timm Wrase
Title: Scale separated AdS vacua?
Venue: Virtual

Abstract: In this talk I will review massive type IIA flux compactifications that seem to give rise to infinite families of supersymmetric 4d AdS vacua. These vacua provide an interesting testing ground for the swampland program. After reviewing potential shortcomings of this setup, I will discuss recent progress on overcoming them and getting a better understanding of these solutions.

  • November 22, 2021 01:00 PM
Speaker: Thomas Grimm
Title: Taming the Landscape
Venue: Virtual

Abstract: In this talk I will introduce a generalized notion of finiteness that provides a structural principle for the set of effective theories that can be consistently coupled to quantum gravity. More concretely, I will propose a ‘tameness conjecture’ that states that all scalar field spaces and coupling functions that appear in such an effective theory must be definable in an o-minimal structure. The fascinating field of tame geometry has seen much recent progress and I will argue that the results can be used to support the above swampland conjecture. The strongest evidence arises from a new finiteness theorem for the flux landscape which is shown using the tameness of the period map.

  • November 15, 2021 01:00 PM
Speaker: Nima Arkani-Hamed (IAS), and Gary Shiu (UW-Madison)
Title: Swampland Seminar
Venue: Virtual

This week’s seminar will be an open mic discussion which will be led by Nima Arkani-Hamed (IAS), and by Gary Shiu (UW-Madison), and the topic will be “Swampland constraints, Unitarity and Causality”. They will start with a brief introduction sharing their thoughts about the topic and moderate a discussion afterwards.