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  • Journal article
    Dechant P-P, He Y-H, Heyes E, Hirst Eet al., 2023,

    Cluster algebras: Network science and machine learning

    , Journal of Computational Algebra, Vol: 8, Pages: 100008-100008, ISSN: 2772-8277
  • Journal article
    Tseytlin AA, 2023,

    Comments on a 4-derivative scalar theory in 4 dimensions

    , Theoretical and Mathematical Physics, Vol: 217, Pages: 1969-1986, ISSN: 0040-5779

    We review and elaborate on some aspects of the classically scale-invariant renormalizable 4-derivative scalartheory L = φ ∂4φ + g(∂φ)4. Similar models appear, e.g., in the context of conformal supergravity or inthe description of the crystalline phase of membranes. Considering this theory in Minkowski signature, wesuggest how to define Poincar´e-invariant scattering amplitudes by assuming that only massless oscillating(nongrowing) modes appear as external states. In such shift-symmetric interacting theory, there are no IRdivergences despite the presence of 1/q4 internal propagators. We discuss how nonunitarity of this theorymanifests itself at the level of the one-loop massless scattering amplitude.
  • Journal article
    Tseytlin AA, 2023,

    Quantum supermembranes and AdS/CFT duality

    , Journal of Experimental and Theoretical Physics, Vol: 137, Pages: 846-863, ISSN: 1063-7761

    We review and extend some recent work on testing AdS/CFT correspondence between U(N)k × U(N)–k Chern-Simons-matter 3d gauge theory and M-theory in AdS4 × S7/Zk background. We demonstrate that 1-loop term in the quantum M2 brane partition function expanded near a classical solution correctly matches localization predictions on the gauge theory side in the case of BPS Wilson loop expectation value and instanton corrections to free energy.
  • Journal article
    Jazayeri S, Renaux-Petel S, 2023,

    Cosmological bootstrap in slow motion

    , The Journal of High Energy Physics, Vol: 2022, ISSN: 1029-8479

    Speed matters. How the masses and spins of new particles active during inflation can be read off from the statistical properties of primordial density fluctuations is well understood. However, not when the propagation speeds of the new degrees of freedom and of the curvature perturbation differ, which is the generic situation in the effective field theory of inflationary fluctuations. Here we use bootstrap techniques to find exact analytical solutions for primordial 2-,3- and 4-point correlators in this context. We focus on the imprints of a heavy relativistic scalar coupled to the curvature perturbation that propagates with a reduced speed of sound cs, hence strongly breaking de Sitter boosts. We show that akin to the de Sitter invariant setup, primordial correlation functions can be deduced by acting with suitable weight-shifting operators on the four-point function of a conformally coupled field induced by the exchange of the massive scalar. However, this procedure requires the analytical continuation of this seed correlator beyond the physical domain implied by momentum conservation. We bootstrap this seed correlator in the extended domain from first principles, starting from the boundary equation that it satisfies due to locality. We further impose unitarity, reflected in cosmological cutting rules, and analyticity, by demanding regularity in the collinear limit of the four-point configuration, in order to find the unique solution. Equipped with this, we unveil that heavy particles that are lighter than H/cs leave smoking gun imprints in the bispectrum in the form of resonances in the squeezed limit, a phenomenon that we call the low speed collider. We characterise the overall shape of the signal as well as its unusual logarithmic mass dependence, both vividly distinct from previously identified signatures of heavy fields. Eventually, we demonstrate that these features can be understood in a simplified picture in which the heavy field is integrated out, albeit
  • Journal article
    Jazayeri S, Renaux-Petel S, Werth D, 2023,

    Shapes of the cosmological low-speed collider

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

    Massive particles produced during inflation leave specific signatures in soft limits of correlation functions of primordial fluctuations. When the Goldstone boson of broken time translations acquires a reduced speed of sound, implying that de Sitter boosts are strongly broken, we introduce a novel discovery channel to detect new physics during inflation, called the cosmological low-speed collider signal. This signal is characterised by a distinctive resonance lying in mildly-soft kinematic configurations of cosmological correlators, indicating the presence of a heavy particle, whose position enables to reconstruct its mass. We show that this resonance can be understood in terms of a non-local single-field effective field theory, in which the heavy field becomes effectively non-dynamical. This theory accurately describes the full dynamics of the Goldstone boson and captures all multi-field physical effects distinct from the non-perturbative particle production leading to the conventional cosmological collider signal. As such, this theory provides a systematic and tractable way to study the imprint of massive fields on cosmological correlators. We conduct a thorough study of the low-speed collider phenomenology in the scalar bispectrum, showing that large non-Gaussianities with new shapes can be generated, in particular beyond weak mixing. We also provide a low-speed collider template for future cosmological surveys.
  • Book
    , 2023,

    Encyclopedia of Cosmology, The, Set 2: Frontiers in Cosmology (in 3 Volumes)

    , ISBN: 9789811289699

    Together, these volumes will be a comprehensive review of the most important current topics in cosmology, discussing the important concepts and current status in each field, covering both theory and observation.These three volumes are ...
  • Book chapter
    Rivers R, Paliou E, Evans T, 2023,

    Gravity and Maximum Entropy Models

    , The Oxford Handbook of Archaeological Network Research, Editors: Brughmans, Mills, Munson, Peeples, Publisher: Oxford University Press, Pages: 186-199, ISBN: 9780198854265

    Gravity models are a class of quantitative models that can be used for describing the spatial characteristics of social interactions, providing a realization of Tobler’s “law” of geography that “near things are more related than distant things.” In archaeology, they are particularly suited for describing historic and prehistoric “exchange” and “settlement formation.” Although, quantitatively, they were originally little more than mimicry of Newtonian gravitation, they arise naturally in some forms of economic modeling and as the “most likely” outcomes (MaxEnt) from limited knowledge. We discuss several of their key applications to archaeological data.
  • Journal article
    Magueijo J, 2023,

    Evolving laws and cosmological energy

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 108, ISSN: 1550-2368

    We couple the issue of evolution in the laws of physics with that of violations of energy conservation. Avoiding a time dependence in terms of coordinate time, we define evolution as a function of time variables canonically dual to “constants” (such as Λ, the Planck mass, or the gravitational coupling), mimicking a procedure associated with one formulation of unimodular gravity. We then introduce variability via a dependence of other fundamental “constants” on these clocks. Although this is not needed, sharper results are obtained if this procedure violates local Lorentz invariance, which we define in the spirit of Horava-Lifshitz theories (modifying a 3+1 split action, so that a Lorentz invariant 4D reassembly is no longer possible). We find that variability in the “laws of physics” generically leads to violations of energy conservation if either a matter parameter varies as a function of a gravitational clock, or a gravity parameter depends on a matter clock, with the other combinations sterile. In general the matter components associated with the varying parameter or the clock absorb or give off the violated energy. We illustrate this with a variety of clocks (ticking unimodular time, Ricci time, etc.) and parameters (mainly the gravitational and matter speed of light, but also Λ). We can accommodate in this construction (and improve on) several early varying speed of light models, allowing for variability effects related to the spatial curvature and Λ to cause creation of radiation and a hot big bang.
  • Journal article
    Benetti Genolini P, Gauntlett JP, Sparks J, 2023,

    Localizing wrapped M5-branes and gravitational blocks

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

    We consider d ¼ 2, N ¼ ð0; 2Þ SCFTs that can arise from M5-branes wrapping four-dimensional,complex, toric manifolds and orbifolds. We use equivariant localization to compute the off-shell centralcharge of the dual supergravity solutions, obtaining a result that can be written as a sum of gravitationalblocks and precisely agrees with a field theory computation using anomaly polynomials and cextremization.
  • Journal article
    Sirks EL, Massey R, Gill AS, Anderson J, Benton SJ, Brown AM, Clark P, English J, Everett SW, Fraisse AA, Franco H, Hartley JW, Harvey D, Holder B, Hunter A, Huff EM, Hynous A, Jauzac M, Jones WC, Joyce N, Kennedy D, Lagattuta D, Leung JS-Y, Li L, Lishman S, Luu TVT, Mccleary JE, Nagy JM, Netterfield CB, Paracha E, Purcaru R, Redmond SF, Rhodes JD, Robertson A, Romualdez LJ, Roth S, Salter R, Schmoll J, Shaaban MM, Smith R, Smith R, Tam SI, Vassilakis GN, Oh H-Uet al., 2023,

    Data Downloaded via Parachute from a NASA Super-Pressure Balloon

    , AEROSPACE, Vol: 10
  • Journal article
    de Rham C, Kozuszek J, Tolley AJ, Wiseman Tet al., 2023,

    Dynamical formulation of ghost-free massive gravity

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 108, ISSN: 1550-7998

    We present a formulation of ghost-free massive gravity with flat reference metric that exhibits the full nonlinear constraint algebraically, in a way that can be directly implemented for numerical simulations. Motivated by the presence of higher order operators in the low-energy effective description of massive gravity, we show how the inclusion of higher-order gradient (dissipative) terms leads to a well-posed formulation of its dynamics. The formulation is presented for a generic combination of the minimal and quadratic mass terms (the phenomenologically interesting case) on any background. For concreteness, we then focus on the numerical evolution of the minimal model for spherically symmetric gravitational collapse of scalar field matter. This minimal model does not carry the relevant interactions to switch on an active Vainshtein mechanism, at least in spherical symmetry, thus we do not expect to recover usual general relativity behavior even for small graviton mass. Nonetheless we may ask what the outcome of matter collapse is for this gravitational theory. Starting with small initial data far away from the center, we follow the matter through a nonlinear regime as it falls towards the origin. For sufficiently weak data the matter disperses. However for larger data we generally find that the classical evolution breaks down resulting in the theory becoming infinitely strongly coupled without the presence of an apparent horizon shielding this behavior from an asymptotic observer.
  • 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
    Gautason FF, Puletti VGM, van Muiden J, 2023,

    Quantized strings and instantons in holography

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>We study worldsheet instantons in holographic type IIA backgrounds directly in string theory. The first background is a dimensional reduction of AdS<jats:sub>7</jats:sub> × <jats:italic>S</jats:italic><jats:sup>4</jats:sup> and is dual to the maximally supersymmetric Yang-Mills theory on <jats:italic>S</jats:italic><jats:sup>5</jats:sup>. The second background is AdS<jats:sub>4</jats:sub> × <jats:bold>C</jats:bold><jats:italic>P</jats:italic><jats:sup>3</jats:sup> dual to ABJM in the type IIA limit. We compute the one-loop partition function of the fundamental string in these backgrounds and show that the result is in exact agreement with field theory predictions. We argue that for higher rank instantons, the string partition function takes a product form of the single instanton partition function times the contribution of two orbifolds on the worldsheet. We determine the orbifold factor to be <jats:italic>n</jats:italic><jats:sup><jats:italic>−</jats:italic>3/2</jats:sup> where <jats:italic>n</jats:italic> is the instanton rank. With this result, we reproduce the series of non-perturbative corrections in <jats:italic>α</jats:italic><jats:sup><jats:italic>′</jats:italic></jats:sup> to the planar <jats:italic>S</jats:italic><jats:sup>5</jats:sup> free energy. When studying the worldsheet instanton partition function on <jats:bold>C</jats:bold><jats:italic>P</jats:italic><jats:sup>3</jats:sup>, we encounter twelve fermionic and twelve bosonic zero modes. By deforming the ABJM theory, the zero-modes are lifted and consequently the tower of worldsheet instantons can be evaluated and m
  • Journal article
    Piazza F, Tolley AJ, 2023,

    Subadditive average distances and quantum promptness

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

    A central property of a classical geometry is that the geodesic distance between two events is additive. When considering quantum fluctuations in the metric or a quantum or statistical superposition of different spacetimes, additivity is generically lost at the level of expectation values. In the presence of a superposition of metrics, distances can be made diffeomorphism invariant by considering the frame of a family of free-falling observers or a pressureless fluid, provided we work at sufficiently low energies. We propose to use the average squared distance between two events <d²(x,y)> as a proxy for understanding the effective quantum (or statistical) geometry and the emergent causal relations among such observers. At each point, the average squared distance <d²(x,y)> defines an average metric tensor. However, due to non-additivity, <d²(x,y)> is not the (squared) geodesic distance associated with it. We show that departures from additivity can be conveniently captured by a bi-local quantity C(x,y). Violations of additivity build up with the mutual separation between x and y and can correspond to C < 0 (subadditive) or C > 0 (superadditive). We show that average Euclidean distances are always subadditive: they satisfy the triangle inequality but generally fail to saturate it. In Lorentzian signature there is no definite result about the sign of C, most physical examples give C < 0 but there exist counterexamples. The causality induced by subadditive Lorentzian distances is unorthodox but not pathological. Superadditivity violates the transitivity of causal relations. On these bases, we argue that subadditive distances are the expected outcome of dynamical evolution, if relatively generic physical initial conditions are considered.
  • 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: Particles, Fields, Gravitation and Cosmology, Vol: 108, ISSN: 1550-7998

    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
    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
    Evnin O, Mkrtchyan K, 2023,

    Three approaches to chiral form interactions

    , DIFFERENTIAL GEOMETRY AND ITS APPLICATIONS, Vol: 89, ISSN: 0926-2245
  • Journal article
    Bobev N, Gautason FF, van Muiden J, 2023,

    Holographic 3d $$ \mathcal{N} $$ = 1 conformal manifolds

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>We construct and study several examples of continuous families of AdS<jats:sub>4</jats:sub><jats:inline-formula><jats:alternatives><jats:tex-math>$$ \mathcal{N} $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>N</mml:mi> </mml:math></jats:alternatives></jats:inline-formula> = 1 solutions of four-dimensional maximal gauged supergravity. These backgrounds provide the holographic descriptions of conformal manifolds of the dual 3d <jats:inline-formula><jats:alternatives><jats:tex-math>$$ \mathcal{N} $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>N</mml:mi> </mml:math></jats:alternatives></jats:inline-formula> = 1 SCFTs. The solutions we study can be uplifted to type IIB supergravity where they arise from D3-branes wrapping an <jats:italic>S</jats:italic><jats:sup>1</jats:sup> with an S-duality twist. We find the spectrum of low lying operators in the 3d <jats:inline-formula><jats:alternatives><jats:tex-math>$$ \mathcal{N} $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>N</mml:mi> </mml:math></jats:alternatives></jats:inline-formula> = 1 SCFTs as a function of the exactly marginal coupling and discuss the structure of the corresponding superconformal multiplets. Using string theory techniques we also study additional examples of continuous families of <jats:inline-formula><jats:alternatives><jats:tex-math>$$ \mathcal{N} $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/Mat
  • 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.

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