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  • Journal article
    de Rham C, Kozuszek J, Tolley AJ, Wiseman Tet al., 2023,

    Dynamical formulation of ghost-free massive gravity

    , PHYSICAL REVIEW D, Vol: 108, ISSN: 2470-0010
  • Journal article
    Toomey MW, Koushiappas SM, Alexandre B, Magueijo Jet al., 2023,

    Quantum gravity signatures in the late Universe

    , Physical Review D, Vol: 108, ISSN: 2470-0010

    We calculate deviations in cosmological observables as a function of parameters in a class of connection-based models of quantum gravity. In this theory nontrivial modifications to the background cosmology can occur due to a distortion of the wave function of the Universe at the transition from matter to dark energy domination (which acts as a “reflection” in connection space). We are able to exclude some regions of parameter space and show with projected constraints that future experiments like DESI will be able to further constrain these models. An interesting feature of this theory is that there exists a region of parameter space that could naturally alleviate the S8 tension.
  • Journal article
    Beccaria M, Giombi S, Tseytlin AA, 2023,

    Instanton contributions to the ABJM free energy from quantum M2 branes

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Boido A, Gauntlett JP, Martelli D, Sparks Jet al., 2023,

    Gravitational blocks, spindles and GK geometry

    , Communications in Mathematical Physics, Vol: 403, Pages: 917-1003, ISSN: 0010-3616

    We derive a gravitational block formula for the supersymmetric action for ageneral class of supersymmetric AdS solutions, described by GK geometry. Extremalpoints of this action describe supersymmetric AdS3 solutions of type IIB supergravity,sourced by D3-branes, and supersymmetric AdS2 solutions of D = 11 supergravity,sourced by M2-branes. In both cases, the branes are also wrapped over a two-dimensionalorbifold known as a spindle, or a two-sphere. We develop various geometric methodsfor computing the gravitational block contributions, allowing us to recover previouslyknown results for various explicit supergravity solutions, and to significantly generalizethese results to other compactifications. For the AdS3 solutions we give a general proofthat our off-shell supersymmetric action agrees with an appropriate off-shell c-functionin the dual field theory, establishing a very general exact result in holography. Forthe AdS2 solutions our gravitational block formula allows us to obtain the entropy forsupersymmetric, magnetically charged and accelerating black holes in AdS4.
  • Journal article
    Genolini PB, Gauntlett JP, Sparks J, 2023,

    Equivariant localization in supergravity

    , Physical Review Letters, Vol: 131, ISSN: 0031-9007

    We show that supersymmetric supergravity solutions with an R-symmetry Killing vector are equipped with a set of equivariantly closed forms. Various physical observables may be expressed as integrals of these forms, and then evaluated using the Berline-Vergne-Atiyah-Bott fixed point theorem. We illustrate with a variety of holographic examples, including on-shell actions, black hole entropies, central charges, and scaling dimensions of operators. The resulting expressions depend only on topological data and the R-symmetry vector, and hence may be evaluated without solving the supergravity equations.
  • Journal article
    Bourget A, Grimminger JF, Hanany A, Kalveks R, Sperling M, Zhong Zet al., 2023,

    A tale of N cones

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Mccleary JE, Everett SW, Shaaban MM, Gill AS, Vassilakis GN, Huff EM, Massey RJ, Benton SJ, Brown AM, Clark P, Holder B, Fraisse AA, Jauzac M, Jones WC, Lagattuta D, Leung JS-Y, Li L, T Luu TV, Nagy JM, Netterfield CB, Paracha E, Redmond SF, Rhodes JD, Schmoll J, Sirks E, Tam SIet al., 2023,

    Lensing in the Blue. II. Estimating the Sensitivity of Stratospheric Balloons to Weak Gravitational Lensing

    , ASTRONOMICAL JOURNAL, Vol: 166, ISSN: 0004-6256
  • Journal article
    Beccaria M, Tseytlin AA, 2023,

    Comments on ABJM free energy on S3 at large N and perturbative expansions in M-theory and string theory

    , Nuclear Physics B, Vol: 994, ISSN: 0550-3213

    We compare large N expansion of the localization result for the free energy F in the 3d N = 6 superconformal U(N)k × U(N)−k Chern-Simons-matter theory to its AdS/CFT counterpart, i.e. to the perturbativeexpansion of M-theory partition function on AdS4 × S7/Zk and to the weak string coupling expansionof type IIA effective action on AdS4 × CP3. We show that the general form of the perturbative expansions of F on the two sides of the AdS/CFT duality is indeed the same. Moreover, the transcendentalityproperties of the coefficients in the large N, large k expansion of F match those in the corresponding Mtheory or string theory expansions. To shed light on the structure of the 1-loop M-theory partition functionon AdS4 × S7/Zk we use the expression for the 1-loop 4-graviton scattering amplitude in the 11d supergravity. We also use the known information about the transcendental coefficients of the leading curvatureinvariants in the low-energy effective action of type II string theory. Matching of the remaining rationalfactors in the coefficients requires a precise information about currently unknown RR field strength termsin the corresponding superinvariants.
  • Journal article
    Piazza F, Tolley AJ, 2023,

    Subadditive average distances and quantum promptness

    , CLASSICAL AND QUANTUM GRAVITY, Vol: 40, ISSN: 0264-9381
  • Journal article
    Auclair P, Bacon D, Baker T, Barreiro T, Bartolo N, Belgacem E, Bellomo N, Ben-Dayan I, Bertacca D, Besancon M, Blanco-Pillado JJ, Blas D, Boileau G, Calcagni G, Caldwell R, Caprini C, Carbone C, Chang C-F, Chen H-Y, Christensen N, Clesse S, Comelli D, Congedo G, Contaldi C, Crisostomi M, Croon D, Cui Y, Cusin G, Cutting D, Dalang C, De Luca V, Pozzo WD, Desjacques V, Dimastrogiovanni E, Dorsch GC, Ezquiaga JM, Fasiello M, Figueroa DG, Flauger R, Franciolini G, Frusciante N, Fumagalli J, García-Bellido J, Gould O, Holz D, Iacconi L, Jain RK, Jenkins AC, Jinno R, Joana C, Karnesis N, Konstandin T, Koyama K, Kozaczuk J, Kuroyanagi S, Laghi D, Lewicki M, Lombriser L, Madge E, Maggiore M, Malhotra A, Mancarella M, Mandic V, Mangiagli A, Matarrese S, Mazumdar A, Mukherjee S, Musco I, Nardini G, No JM, Papanikolaou T, Peloso M, Pieroni M, Pilo L, Raccanelli A, Renaux-Petel S, Renzini AI, Ricciardone A, Riotto A, Romano JD, Rollo R, Pol AR, Morales ER, Sakellariadou M, Saltas ID, Scalisi M, Schmitz K, Schwaller P, Sergijenko O, Servant G, Simakachorn P, Sorbo L, Sousa L, Speri L, Steer DA, Tamanini N, Tasinato G, Torrado J, Unal C, Vennin V, Vernieri D, Vernizzi F, Volonteri M, Wachter JM, Wands D, Witkowski LT, Zumalacárregui M, Annis J, Ares FR, Avelino PP, Avgoustidis A, Barausse E, Bonilla A, Bonvin C, Bosso P, Calabrese M, Çalışkan M, Cembranos JAR, Chala M, Chernoff D, Clough K, Criswell A, Das S, Silva AD, Dayal P, Domcke V, Durrer R, Easther R, Escoffier S, Ferrans S, Fryer C, Gair J, Gordon C, Hendry M, Hindmarsh M, Hooper DC, Kajfasz E, Kopp J, Koushiappas SM, Kumar U, Kunz M, Lagos M, Lilley M, Lizarraga J, Lobo FSN, Maleknejad A, Martins CJAP, Meerburg PD, Meyer R, Mimoso JP, Nesseris S, Nunes N, Oikonomou V, Orlando G, Özsoy O, Pacucci F, Palmese A, Petiteau A, Pinol L, Zwart SP, Pratten G, Prokopec T, Quenby J, Rastgoo S, Roest D, Rummukainen K, Schimd C, Secroun A, Sesana A, Sopuerta CF, Tereno I, Tolley A, Urrestilla J, Vagenas EC, van de Vis J, van de Weyget al., 2023,

    Cosmology with the Laser Interferometer Space Antenna

    , Living Reviews in Relativity, Vol: 26, ISSN: 1433-8351

    The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational-wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational-wave observations by LISA to probe the universe.
  • Journal article
    Gkountoumis G, Hull C, Stemerdink K, Vandoren Set al., 2023,

    Freely acting orbifolds of type IIB string theory on T<SUP>5</SUP>

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
    • Cite
    • Citations: 14
  • Journal article
    De Rham C, Jaitly S, Tolley AJ, 2023,

    Constraints on Regge behavior from IR physics

    , Physical Review D, Vol: 108, ISSN: 2470-0010

    We consider positivity constraints applicable to the effective field theory (EFT) of gravity in arbitrary dimensions. By considering scattering of indefinite initial and final states, we highlight the existence of a gravitational scattering amplitude for which full crossing symmetry is manifest and utilize the recently developed crossing symmetric dispersion relations to derive compact nonlinear bounds. We show that the null constraints built into these dispersion relations lead to a finite energy sum rule for gravity which may be extended to a one-parameter family of continuous moment sum rules. These sum rules enforce a UV-IR relation which imposes constraints on both the Regge trajectory and residue. We also highlight a situation where the Regge trajectory is uniquely determined in terms of the sub-Regge scale amplitude. Generically the Regge behavior may be split into an IR sensitive part calculable within a given EFT, which mainly depends on the lightest fields in nature, and an IR independent part, which is subject to universal positivity constraints following from unitarity and analyticity.
  • Journal article
    Smith GR, Waldram D, 2023,

    M-theory moduli from exceptional complex structures

    , The Journal of High Energy Physics, Vol: 2023, ISSN: 1029-8479

    We continue the analysis of the geometry of generic Minkowski N = 1, D = 4flux compactifications in M-theory using exceptional generalised geometry, including thecalculation of the infinitesimal moduli spaces. The backgrounds can be classified into twoclasses: type-0 and type-3. For type-0, we review how the moduli arise from standard deRham cohomology classes. We also argue that, under reasonable assumptions, there areno appropriate sources to support compact flux backgrounds for this class and so the onlysolutions are in fact G2 geometries. For type-3 backgrounds, given a suitable ∂0∂¯0-lemma,we show that the moduli can be calculated from a cohomology based on an involutive subbundle of the complexified tangent space. Using a simple spectral sequence we prove quitegenerally that the presence of flux can only reduce the number of moduli compared withthe fluxless case. We then use the formalism to calculate the moduli of heterotic M-theoryand show they match those of the dual Hull-Strominger system as expected.
  • Journal article
    Dowker F, Zalel S, 2023,

    Observables for cyclic causal set cosmologies

    , Classical and Quantum Gravity, Vol: 40, ISSN: 0264-9381

    In causal set theory, cycles of cosmic expansion and collapse are modelled by causal sets with 'breaks' and 'posts' and a special role is played by cyclic dynamics in which the universe goes through perpetual cycles. We identify and characterise two algebras of observables for cyclic dynamics in which the causal set universe has infinitely many breaks. The first algebra is constructed from the cylinder sets associated with finite causal sets that have a single maximal element and offers a new framework for defining cyclic dynamics as random walks on a novel tree. The second algebra is generated by a collection of stem-sets and offers a physical interpretation of the observables in these models as statements about unlabelled stems with a single maximal element. There are analogous theorems for cyclic dynamics in which the causal set universe has infinitely many posts.
  • Journal article
    Evnin O, Mkrtchyan K, 2023,

    Three approaches to chiral form interactions

    , DIFFERENTIAL GEOMETRY AND ITS APPLICATIONS, Vol: 89, ISSN: 0926-2245
  • Journal article
    Mentasti G, Contaldi CR, Peloso M, 2023,

    Prospects for detecting anisotropies and polarization of the stochastic gravitational wave background with ground-based detectors

    , Journal of Cosmology and Astroparticle Physics, Vol: 2023, Pages: 053-053, ISSN: 1475-7516

    We build an analytical framework to study the observability of anisotropies and a net chiral polarization of the Stochastic Gravitational Wave Background (SGWB) with a generic network of ground-based detectors. We apply this formalism to perform a Fisher forecast of the performance of a network consisting of the current interferometers (LIGO, Virgo and KAGRA) and planned third-generation ones, such as the Einstein Telescope and Cosmic Explorer. Our results yield limits on the observability of anisotropic modes, spanning across noise- and signal-dominated regimes. We find that if the isotropic component of the SGWB has an amplitude close to the current limit, third-generation interferometers with an observation time of 10 years can measure multipoles (in a spherical harmonic expansion) up to ℓ = 8 with Script O(10-3 – 10-2) accuracy relative to the isotropic component, and an Script O(10-3) amount of net polarization. For weaker signals, the accuracy worsens as roughly the inverse of the SGWB amplitude.
  • Journal article
    Ashmore A, He Y-H, Heyes E, Ovrut BAet al., 2023,

    Numerical spectra of the Laplacian for line bundles on Calabi-Yau hypersurfaces

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>We give the first numerical calculation of the spectrum of the Laplacian acting on bundle-valued forms on a Calabi-Yau three-fold. Specifically, we show how to compute the approximate eigenvalues and eigenmodes of the Dolbeault Laplacian acting on bundle-valued (<jats:italic>p</jats:italic>, <jats:italic>q</jats:italic>)-forms on Kähler manifolds. We restrict our attention to line bundles over complex projective space and Calabi-Yau hypersurfaces therein. We give three examples. For two of these, ℙ<jats:sup>3</jats:sup> and a Calabi-Yau one-fold (a torus), we compare our numerics with exact results available in the literature and find complete agreement. For the third example, the Fermat quintic three-fold, there are no known analytic results, so our numerical calculations are the first of their kind. The resulting spectra pass a number of non-trivial checks that arise from Serre duality and the Hodge decomposition. The outputs of our algorithm include all the ingredients one needs to compute physical Yukawa couplings in string compactifications.</jats:p>
  • Journal article
    Chester SM, Dupuis É, Witczak-Krempa W, 2023,

    Evidence for web of dualities from monopole operators

    , Physical Review D, Vol: 108, ISSN: 2470-0010

    We give evidence for the web of 3d bosonization dualities in conformal field theories (CFTs) by computing monopole operator scaling dimensions in (2+1)-dimensional quantum electrodynamics (QED3) with Chern-Simons level k and N complex bosons in a large-N, k expansion. We first consider the k=0 case, where we show that scaling dimensions previously computed to subleading order in 1/N can be extrapolated to N=1 and matched to O(2) Wilson-Fisher CFT scaling dimensions with around 5% error, which is evidence for particle-vortex duality. We then generalize the subleading calculation to large N, k and fixed k/N, extrapolate to N=k=1, and consider monopole operators that are conjectured to be dual to nondegenerate scalar operators in a theory of a single Dirac fermion. We find matches typically with 1% error or less, which is strong evidence of this so-called "seed"duality that implies a web of 3d bosonization dualities among CFTs.
  • Journal article
    Alexandre B, Isichei R, Magueijo J, 2023,

    Unitary and Vilenkin's wave functions

    , Physical Review D, Vol: 108, ISSN: 2470-0010

    It is remarkably difficult to reconcile unitarity and Vilenkin’s wave function. For example, the natural conserved inner product found in quantum unimodular gravity applies to the Hartle-Hawking wave function, but fails for its Vilenkin counterpart. We diagnose this failure from different angles (Laplace transform instead of Fourier transform, non-Hermiticity of the Hamiltonian, etc.) to conclude that ultimately it stems from allowing the connection to become imaginary in a section of its contour. In turn this is the unavoidable consequence of representing the Euclidean theory as an imaginary image within a fundamentally Lorentzian theory. It is nonetheless possible to change the underlying theory and replace the connection’s foray into the imaginary axis by an actual signature change (with the connection, action and Hamiltonian remaining real). The structural obstacles to unitarity are then removed, but special care must still be taken, because the Euclidean theory a priori has boundaries, so that appropriate boundary conditions are required for unitarity. Reflecting boundary conditions would reinstate a Hartle-Hawking-like solution in the Lorentzian regime. To exclude an incoming wave in the Lorentzian domain one must allow a semi-infinite tower of spheres in the Euclidean region, wave packets traveling through successive spheres for half an eternity in unimodular time. Such a “Sisyphus” boundary condition no longer even vaguely resembles Vilenkin’s original proposal.
  • Journal article
    de Rham C, Garcia-Saenz S, Heisenberg L, Pozsgay V, Wang Xet al., 2023,

    To half-be or not to be?

    , The Journal of High Energy Physics, Vol: 2023, Pages: 1-31, ISSN: 1029-8479

    It has recently been argued that half degrees of freedom could emerge in Lorentz and parity invariant field theories, using a non-linear Proca field theory dubbed Proca-Nuevo as a specific example. We provide two proofs, using the Lagrangian and Hamiltonian pictures, that the theory possesses a pair of second class constraints, leaving D − 1 degrees of freedom in D spacetime dimensions, as befits a consistent Proca model. Our proofs are explicit and straightforward in two dimensions and we discuss how they generalize to an arbitrary number of dimensions. We also clarify why local Lorentz and parity invariant field theories cannot hold half degrees of freedom.
  • Journal article
    Beccaria M, Korchemsky GP, Tseytlin AA, 2023,

    Non-planar corrections in orbifold/orientifold <i>N</i>=2 superconformal theories from localization

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
    • Cite
    • Citations: 14
  • Journal article
    Giombi S, Tseytlin AA, 2023,

    Wilson Loops at Large N and the Quantum M2-Brane

    , PHYSICAL REVIEW LETTERS, Vol: 130, ISSN: 0031-9007
    • Cite
    • Citations: 19
  • Journal article
    Camargo-Molina JE, Rajantie A, 2023,

    Phase transitions in de Sitter spacetimes: The stochastic formalism

    , PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010
  • Journal article
    Dunning J, Burke T, Chan AHH, Chik HYJ, Evans T, Schroeder Jet al., 2023,

    Opposite-sex associations are linked with annual fitness, but sociality is stable over lifetime

    , Behavioral Ecology, Vol: 315, Pages: 315-324, ISSN: 1045-2249

    Animal sociality, an individual’s propensity to associate with others, has fitness consequences through mate choice, for example, directly, by increasing the pool of prospective partners, and indirectly through increased survival, and individuals benefit from both. Annually, fitness consequences are realized through increased mating success and subsequent fecundity. However, it remains unknown whether these consequences translate to lifetime fitness. Here, we quantified social associations and their link to fitness annually and over lifetime, using a multi-generational, genetic pedigree. We used social network analysis to calculate variables representing different aspects of an individual’s sociality. Sociality showed high within-individual repeatability. We found that birds with more opposite-sex associates had higher annual fitness than those with fewer, but this did not translate to lifetime fitness. Instead, for lifetime fitness, we found evidence for stabilizing selection on opposite-sex sociality, and sociality in general, suggesting that reported benefits are only short-lived in a wild population, and that selection favors an average sociality.
  • Journal article
    Mawby C, Halliwell JJ, 2023,

    Leggett-Garg violations for continuous-variable systems with Gaussian states

    , PHYSICAL REVIEW A, Vol: 107, ISSN: 2469-9926
  • Journal article
    Gledhill K, Hanany A, 2023,

    Poisson brackets for some Coulomb branches

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Camargo-Molina JE, Gonzalez MC, Rajantie A, 2023,

    Phase transitions in de Sitter spacetimes: Quantum Corrections

    , PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010
  • Journal article
    Alexandre B, Magueijo J, 2023,

    Unimodular Hartle-Hawking wave packets and their probability interpretation

    , Physical Review D, Vol: 107, ISSN: 2470-0010

    We reexamine the Hartle-Hawking wave function from the point of view of a quantum theory whichstarts from the connection representation and allows for off-shell nonconstancy of Λ (as in unimodulartheory), with a concomitant dual relational time variable. By translating its structures to the metricrepresentation we find a nontrivial inner product rendering wave packets of Hartle-Hawking wavesnormalizable and the time evolution unitary; however, the implied probability measure differssignificantly from the naive jψj2. In contrast with the (monochromatic) Hartle-Hawking wave function,these packets form traveling waves with a probability peak describing de Sitter space, except near thebounce, where the incident and reflected waves interfere, transiently recreating the usual standing wave.Away from the bounce the packets get sharper both in metric and connection space, an apparentcontradiction with Heisenberg’s principle allowed by the fact that the metric is not Hermitian, eventhough its eigenvalues are real. Near the bounce, the evanescent wave not only penetrates into theclassically forbidden region but also extends into the a2 < 0 Euclidean domain. We work out thepropagators for this theory and relate them to the standard ones. The a ¼ 0 point (aka the “nothing”) isunremarkable, and in any case a wave function peaked therein is typically non-normalizable and/orimplies a nonsensical probability for Λ (which the Universe would preserve forever). Within this theory itmakes more sense to adopt a Gaussian state in an appropriate function of Λ, and use the probabilityassociated with the evanescent wave present near the time of the bounce as a measure of the likelihood ofcreation of a pair of time-symmetric semiclassical Universes.
  • Journal article
    Mkrtchyan K, Valach F, 2023,

    Democratic actions for type II supergravities

    , PHYSICAL REVIEW D, Vol: 107, ISSN: 2470-0010
  • Journal article
    De Biasio D, Freigang J, Luest D, Wiseman Tet al., 2023,

    Gradient flow of Einstein-Maxwell theory and Reissner-Nordstrom black holes

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479

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