208 citations · 474 across the 14 of their papers we have counts for
15 papers
Wormholes as red herrings: reflection positivity and the reconstruction of unitary quantum field theories
Jacob McNamara, Zhencheng Wang
As Coleman famously argued, the apparent breakdown of partition-function factorization in quantum gravity associated with Euclidean wormholes is a red herring, arising from a hidde…
GSO Defects: IIA/IIB Walls and the Surprisingly Stable -Brane
Jonathan J. Heckman, Jacob McNamara, Julio Parra-Martinez +1
The recently proposed Swampland Cobordism Conjecture predicts the existence of new non-supersymmetric objects which supplement the spectrum of low-energy gravitational effective fi…
Wormhole Renormalization: The gravitational path integral, holography, and a gauge group for topology change
Elliott Gesteau, Matilde Marcolli, Jacob McNamara
We study the Factorization Paradox from the bottom up by adapting methods from perturbative renormalization. Just as quantum field theories are plagued with loop divergences that n…
On the Fate of Stringy Non-Invertible Symmetries
Jonathan J. Heckman, Jacob McNamara, Miguel Montero +3
Non-invertible symmetries in quantum field theory (QFT) generalize the familiar product rule of groups to a more general fusion rule. In many cases, gauged versions of these symmet…
Non-standard axion electrodynamics and the dual Witten effect
Ben Heidenreich, Jacob McNamara, Matthew Reece
Standard axion electrodynamics has two closely related features. First, the coupling of a massless axion field to photons is quantized, in units proportional to the electric gauge…
Running Decompactification, Sliding Towers, and the Distance Conjecture
Muldrow Etheredge, Ben Heidenreich, Jacob McNamara +3
We study towers of light particles that appear in infinite-distance limits of moduli spaces of 9-dimensional string theories, some of which notably feature decompac…
Reflections on Parity Breaking
Jacob McNamara, Matthew Reece
Parity and CP symmetries are broken in the world around us. Nonetheless, parity (or CP) may be a gauge symmetry which is higgsed in our universe. This is assumed in many scenarios…
Gravitational Solitons and Completeness
Jacob McNamara
We show that gravitational solitons naturally carry gauge charges beyond those of any local quantum field. The effect of these charged excitations is to break a non-invertible symm…
Non-Invertible Global Symmetries and Completeness of the Spectrum
Ben Heidenreich, Jacob McNamara, Miguel Montero +3
It is widely believed that consistent theories of quantum gravity satisfy two basic kinematic constraints: they are free from any global symmetry, and they contain a complete spect…
Chern-Weil Global Symmetries and How Quantum Gravity Avoids Them
Ben Heidenreich, Jacob McNamara, Miguel Montero +3
We draw attention to a class of generalized global symmetries, which we call "Chern-Weil global symmetries," that arise ubiquitously in gauge theories. The Noether currents of thes…
Baby Universes, Holography, and the Swampland
Jacob McNamara, Cumrun Vafa
On the basis of a number of Swampland conditions, we argue that the Hilbert space of baby universe states must be one-dimensional in a consistent theory of quantum gravity. This sc…
Cobordism Classes and the Swampland
Jacob McNamara, Cumrun Vafa
We argue that any proposed quantum theory of gravity with non-trivial cobordism classes in the space of configurations belongs to the Swampland. The argument is based on the assump…
Topological Chern-Simons/Matter Theories
Mina Aganagic, Kevin Costello, Jacob McNamara +1
We propose a new partially topological theory in three dimensions which couples Chern-Simons theory to matter. The 3-manifolds needed for this construction admit transverse holomor…
Limiting behavior of Donaldson's heat flow on non-Kähler surfaces
Jacob McNamara, Yifei Zhao
Let be a compact Hermitian surface, and be any fixed Gauduchon metric on . Let be an Hermitian holomorphic vector bundle over . On the bundle , Donaldson's hea…
A Bound on the Norm of Shortest Vectors in Lattices Arising from CM Number Fields
Jacob McNamara
This paper partially addresses the problem of characterizing the lengths of vectors in a family of Euclidean lattices that arise from any CM number field. We define a modified quad…