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  • Journal article
    Magueijo J, 2024,

    Spacetime symmetry breaking on nongeodesic leaves and a new form of matter

    , PHYSICAL REVIEW D, Vol: 110, ISSN: 2470-0010
  • Journal article
    Leung R, Stelle KS, 2024,

    Localised gravity and resolved braneworlds

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Fredenhagen S, Lausch F, Mkrtchyan K, 2024,

    Interactions of massless fermionic fields in three dimensions

    , PHYSICAL REVIEW D, Vol: 110, ISSN: 2470-0010
  • Journal article
    Hull C, Hutt ML, Lindstrom U, 2024,

    Gauge-invariant magnetic charges in linearised gravity

    , CLASSICAL AND QUANTUM GRAVITY, Vol: 41, ISSN: 0264-9381
  • Journal article
    Shaw EC, Ade PAR, Akers S, Amiri M, Austermann J, Beall J, Becker DT, Benton SJ, Bergman AS, Bock JJ, Bond JR, Bryan SA, Chiang HC, Contaldi CR, Domagalski RS, Doré O, Duff SM, Duivenvoorden AJ, Eriksen HK, Farhang M, Filippini JP, Fissel LM, Fraisse AA, Freese K, Galloway M, Gambrel AE, Gandilo NN, Ganga K, Gibbs SM, Gourapura S, Grigorian A, Gualtieri R, Gudmundsson JE, Halpern M, Hartley J, Hasselfield M, Hilton G, Holmes W, Hristov VV, Huang Z, Hubmayr J, Irwin KD, Jones WC, Kahn A, Kermish ZD, King C, Kuo CL, Lennox AR, Leung JSY, Li S, Luu TVT, Mason PV, May J, Megerian K, Moncelsi L, Morford TA, Nagy JM, Nie R, Netterfield CB, Nolta M, Osherson B, Padilla IL, Rahlin AS, Redmond S, Reintsema C, Romualdez LJ, Ruhl JE, Runyan MC, Shariff JA, Shiu C, Soler JD, Song X, Tartakovsky S, Thommesen H, Trangsrud A, Tucker C, Turner AD, Ullom J, Van Der List JF, Van Lanen J, Vissers MR, Weber AC, Wehus IK, Wen S, Wiebe DV, Young EYet al., 2024,

    In-flight performance of Spider's 280-GHz receivers

    , Journal of Astronomical Telescopes, Instruments, and Systems, Vol: 10, ISSN: 2329-4124

    Spider is a balloon-borne instrument designed to map the cosmic microwave background at degree-angular scales in the presence of Galactic foregrounds. Spider has mapped a large sky area in the Southern Hemisphere using more than 2000 transition-edge sensors (TESs) during two NASA Long Duration Balloon flights above the Antarctic continent. During its first flight in January 2015, Spider was observed in the 95- and 150-GHz frequency bands, setting constraints on the B-mode signature of primordial gravitational waves. Its second flight in the 2022-2023 season added new receivers at 280 GHz, each using an array of TESs coupled to the sky through feedhorns formed from stacks of silicon wafers. These receivers are optimized to produce deep maps of polarized Galactic dust emission over a large sky area, providing a unique data set with lasting value to the field. We describe the instrument's performance during Spider's second flight, focusing on the performance of the 280-GHz receivers. We include details on the flight, in-band optical loading at float, and an early analysis of detector noise.
  • Journal article
    Caprini C, Jinno R, Lewicki M, Madge E, Merchand M, Nardini G, Pieroni M, Pol AR, Vaskonen Vet al., 2024,

    Gravitational waves from first-order phase transitions in LISA: reconstruction pipeline and physics interpretation

    , JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, ISSN: 1475-7516
  • Journal article
    Benetti Genolini P, Gauntlett JP, Jiao Y, Lüscher A, Sparks Jet al., 2024,

    Localization of the free energy in supergravity

    , Physical Review Letters, Vol: 133, ISSN: 0031-9007

    We derive a general formula for the gravitational free energy of Euclidean supersymmetric solutions toD ¼ 4, N ¼ 2 gauged supergravity coupled to vector multiplet matter. This allows one to compute the freeenergy without solving any supergravity equations, just assuming the solutions exist. As well as recoveringsome known results in the literature with ease, we also present new supergravity results that match withholographically dual field theory computations.
  • Journal article
    Viegas E, Evans T, Viegas E, Evans TSet al., 2024,

    The Behavioural House Indicator: a faster and real time small-area indicative deprivation measure for England

    , Environment and Planning B: Urban Analytics and City Science, ISSN: 2399-8083

    Researchers have been long preoccupied with the measuring and monitoring of economic and social deprivation at small scales, neighbourhood, level in order to provide official government agencies and policy makers with more precise data insights. Whist valuable methodologies have been developed, the exercise of data collection associated with these methods tends to be expensive, time consuming, published infrequently with significant time delays, and subject to recurring changes to methodology. Here, we propose a novel method based on a straightforward methodology and data sources to generate a faster and real time indicator for deprivation at different scaling, small to larger areas. The results of our work show that our method provides a consistent view of deprivation across the regions of England and Wales, which are in line with the other indexes, but also highlight specific flash points of deep rural and highly dense urban deprivation areas that are not well captured by existing indexes. Our method is intended to aid researchers and policy makers by complementing existing but infrequent indexes.
  • Journal article
    Babak S, Falxa M, Franciolini G, Pieroni Met al., 2024,

    Forecasting the sensitivity of pulsar timing arrays to gravitational wave backgrounds

    , Physical Review B, Vol: 110, ISSN: 2469-9950

    Pulsar timing array (PTA) observations hinted towards the existence of a stochastic gravitational wave background (SGWB) in the nHz frequency band. Still, the nature of the SGWB signal cannot be confidently inferred from current data, and the leading explanation invokes mergers of supermassive black holes. If confirmed, such discovery would not only represent a turning point in our understanding of astrophysics, but it may severely limit the capability of searching for additional cosmological sources in the nHz frequency range. In this work, we build a simple framework to forecast the sensitivity of future pulsar timing array configurations and assess the parameter estimation of SGWB, which could consist of several contributions. We release the python code fastpta, implementing this framework and ready to use.
  • Journal article
    Babak S, Falxa M, Franciolini G, Pieroni Met al., 2024,

    Forecasting the sensitivity of pulsar timing arrays to gravitational wave backgrounds

    , PHYSICAL REVIEW D, Vol: 110, ISSN: 2470-0010
  • Journal article
    Arav I, Gauntlett JP, Jiao Y, Roberts MM, Rosen Cet al., 2024,

    Superconformal monodromy defects in N=4 SYM andLS theory

    , The Journal of High Energy Physics, Vol: 2024, ISSN: 1029-8479

    We study type IIB supergravity solutions that are dual to two-dimensionalsuperconformal defects in d = 4 SCFTs which preserve N = (0, 2) supersymmetry. Weconsider solutions dual to defects in N = 4 SYM theory that have non-trivial monodromy forU(1)3 ⊂ SO(6) global symmetry and we also allow for the possibility of conical singularities.In addition, we consider the addition of fermionic and bosonic mass terms that have nontrivial dependence on the spatial directions transverse to the defect, while preserving thesuperconformal symmetry of the defect. We compute various physical quantities including thecentral charges of the defect expressed as a function of the monodromy, the on-shell action aswell as associated supersymmetric Rényi entropies. Analogous computations are carried outfor superconformal defects in the N = 1, d = 4 Leigh-Strassler SCFT. We also show thatthe defects of the two SCFTs are connected by a line of bulk marginal mass deformationsand argue that they are also related by bulk RG fow.
  • Journal article
    Acharya B, Alexandre J, Behera SC, Benes P, Bergmann B, Bertolucci S, Bevan A, Brancaccio R, Branzas H, Burian P, Campbell M, Cecchini S, Cho YM, de Montigny M, De Roeck A, Ellis JR, Fairbairn M, Felea D, Frank M, Gould O, Hays J, Hirt AM, Ho DL-J, Hung PQ, Janecek J, Kalliokoski M, Lacarrere DH, Leroy C, Levi G, Margiotta A, Maselek R, Maulik A, Mauri N, Mavromatos NE, Millward L, Mitsou VA, Musumeci E, Ostrovskiy I, Ouimet P-P, Papavassiliou J, Patrizii L, Pavalas GE, Pinfold JL, Popa LA, Popa V, Pozzato M, Pospisil S, Rajantie A, de Austri RR, Sahnoun Z, Sakellariadou M, Sakurai K, Sarkar S, Semenoff G, Shaa A, Sirri G, Sliwa K, Soluk R, Spurio M, Staelens M, Suk M, Tenti M, Togo V, Tuszynski JA, Upreti A, Vento V, Vives Oet al., 2024,

    MoEDAL Search in the CMS Beam Pipe for Magnetic Monopoles Produced via the Schwinger Effect

    , PHYSICAL REVIEW LETTERS, Vol: 133, ISSN: 0031-9007
  • Journal article
    Seibold FK, Tseytlin AA, 2024,

    Scattering on the supermembrane

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Gill AS, Benton SJ, Damaren CJ, Everett SW, Fraisse AA, Hartley JW, Harvey D, Holder B, Huff EM, Jauzac M, Jones WC, Lagattuta D, Leung JSY, Li L, Luu TVT, Massey R, McCleary JE, Nagy JM, Netterfield CB, Paracha E, Redmond SF, Rhodes JD, Robertson A, Romualdez LJ, Schmoll J, Shaaban MM, Sirks EL, Vassilakis GN, Vitorelli AZet al., 2024,

    SuperBIT Superpressure Flight Instrument Overview and Performance: Near-diffraction-limited Astronomical Imaging from the Stratosphere

    , Astronomical Journal, Vol: 168, ISSN: 0004-6256

    SuperBIT was a 0.5 m near-UV to near-infrared wide-field telescope that launched on a NASA superpressure balloon into the stratosphere from New Zealand for a 45-night flight. SuperBIT acquired multiband images of galaxy clusters to study the properties of dark matter using weak gravitational lensing. We provide an overview of the instrument and its various subsystems. We then present the instrument performance from the flight, including the telescope and image stabilization system, the optical system, the power system, and the thermal system. SuperBIT successfully met the instrument’s technical requirements, achieving a telescope pointing stability of 0.″34 ± 0.″10, a focal plane image stability of 0.″055 ± 0.″027, and a point-spread function FWHM of ∼0.″35 over 5-minute exposures throughout the 45-night flight. The telescope achieved a near-diffraction-limited point-spread function in all three science bands (u, b, and g). SuperBIT served as a pathfinder to the GigaBIT observatory, which will be a 1.34 m near-UV to near-infrared balloon-borne telescope.
  • Journal article
    Etkin A, Magueijo J, Rassouli F-S, 2024,

    Vortices, topology and time

    , Physics Letters B: Nuclear Physics and Particle Physics, Vol: 855, ISSN: 0370-2693

    We relate physical time with the topology of magnetic field vortices. We base ourselves on a formulation of unimodular gravity where the cosmological constant Λ appears as the canonical dual to a variable which on-shell becomes four-volume time. If the theory is restricted to a topological axionic form (viz. a parity-odd product of an electric and a magnetic field), such a time variable becomes the spatial integral of the Chern-Simons density. The latter equates to helicity, so that unimodular time is transmuted into the linking number of the vortices of the topological magnetic field, times their flux. With the added postulate that this flux is a universal constant, the flow of time can thus be interpreted as the progressive weaving of further links between magnetic field vortices, each link providing a quantum of time with value related to the fixed flux. Non-abelian extensions, and targetting parameters other than Λ are briefly examined, exposing different types of vortices and a possible role for inter-linking leading to new phenomenology.
  • Journal article
    Jiang H, Tseytlin AA, 2024,

    On co-dimension 2 defect anomalies in <i>N</i>=4 SYM and (2,0) theory via brane probes in AdS/CFT

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Gkountoumis G, Hull C, Vandoren S, 2024,

    Exact moduli spaces for N=2, <i>D</i>=5 freely acting orbifolds

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Hull C, Hutt ML, Lindstrom U, 2024,

    Charges and topology in linearised gravity

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Gonzalez MC, de Rham C, Jaitly S, Pozsgay V, Tokareva Aet al., 2024,

    Positivity-causality competition: a road to ultimate EFT consistency constraints

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Magueijo J, 2024,

    Dark matter and spacetime symmetry restoration

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 109, ISSN: 1550-2368

    We examine local physics in the presence of global variables: variables associated with the whole of the spacelike surfaces of a foliation. These could be the (pseudo)constants of nature and their conjugate times, but our statements are more general. Interactions between the local and the global (for example, dependence of the local action on global times dual to constants) degrades full space-time diffeomorphism invariance down to spatial diffeomorphism invariance, and so an extra degree of freedom appears. When these presumably primordial global interactions switch off, the local action recovers full invariance and so the usual two gravitons, but a legacy matter component is left over, bearing the extra degree of freedom. Under the assumption that the preferred foliation is geodesic, this component behaves like dark matter, except that 3 of its 4 local degrees of freedom are frozen, forcing its rest frame to coincide with the preferred foliation. The nonfrozen degree of freedom (the number density of the effective fluid) is the survivor of the extra “graviton” present in the initial theory and keeps memory of all the past global interactions that took place in a given location in the preferred foliation. Such “painted-on” dark matter is best distinguished from the conventional one in situations where the preferred frame would be preposterous if all 4 degrees of freedom of dark matter were available. We provide one example: an outflowing halo of legacy matter with exact escape speed at each point and a very specific profile, surrounding a condensed structure made of normal matter.
  • Journal article
    Gerhardinger M, Giblin Jr JT, Tolley AJ, Trodden Met al., 2024,

    Simulating a numerical UV completion of quartic Galileons

    , PHYSICAL REVIEW D, Vol: 109, ISSN: 2470-0010
  • Journal article
    Liu X, Santos JE, Wiseman T, 2024,

    New Well-Posed boundary conditions for semi-classical Euclidean gravity

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Basile T, Joung E, Mkrtchyan K, Mojaza Met al., 2024,

    Spinor-helicity representations of particles of any mass in dS 4 and AdS 4 spacetimes

    , PHYSICAL REVIEW D, Vol: 109, ISSN: 2470-0010
  • Journal article
    Mentasti G, Contaldi CR, Peloso M, 2024,

    Probing the galactic and extragalactic gravitational wave backgrounds with space-based interferometers

    , Journal of Cosmology and Astroparticle Physics, Vol: 2024, ISSN: 1475-7516

    We employ the formalism developed in [1] and [2] to study the prospect of detecting an anisotropic Stochastic Gravitational Wave Background (SGWB) with the Laser Interferometer Space Antenna (LISA) alone, and combined with the proposed space-based interferometer Taiji. Previous analyses have been performed in the frequency domain only. Here, we study the detectability of the individual coefficients of the expansion of the SGWB in spherical harmonics, by taking into account the specific motion of the satellites. This requires the use of time-dependent response functions, which we include in our analysis to obtain an optimal estimate of the anisotropic signal. We focus on two applications. Firstly, the reconstruction of the anisotropic galactic signal without assuming any prior knowledge of its spatial distribution. We find that both LISA and LISA with Taiji cannot put tight constraints on the harmonic coefficients for realistic models of the galactic SGWB. We then focus on the discrimination between a galactic signal of known morphology but unknown overall amplitude and an isotropic extragalactic SGWB component of astrophysical origin. In this case, we find that the two surveys can confirm, at a confidence level ≳ 3σ, the existence of both the galactic and extragalactic background if both have amplitudes as predicted in standard models. We also find that, in the LISA-only case, the analysis in the frequency domain (under the assumption of a time average of data taken homogeneously across the year) provides a nearly identical determination of the two amplitudes as compared to the optimal analysis.
  • Journal article
    Abend S, Allard B, Alonso I, Antoniadis J, Araújo H, Arduini G, Arnold AS, Asano T, Augst N, Badurina L, Balaž A, Banks H, Barone M, Barsanti M, Bassi A, Battelier B, Baynham CFA, Beaufils Q, Belić A, Beniwal A, Bernabeu J, Bertinelli F, Bertoldi A, Biswas IA, Blas D, Boegel P, Bogojević A, Böhm J, Böhringer S, Bongs K, Bouyer P, Brand C, Brimis A, Buchmueller O, Cacciapuoti L, Calatroni S, Canuel B, Caprini C, Caramete A, Caramete L, Carlesso M, Carlton J, Casariego M, Charmandaris V, Chen Y-A, Chiofalo ML, Cimbri A, Coleman J, Constantin FL, Contaldi CR, Cui Y, Ros ED, Davies G, Rosendo EDP, Deppner C, Derevianko A, Rham CD, Roeck AD, Derr D, Di Pumpo F, Djordjevic GS, Döbrich B, Domokos P, Dornan P, Doser M, Drougakis G, Dunningham J, Duspayev A, Easo S, Eby J, Efremov M, Ekelof T, Elertas G, Ellis J, Evans D, Fadeev P, Fanì M, Fassi F, Fattori M, Fayet P, Felea D, Feng J, Friedrich A, Fuchs E, Gaaloul N, Gao D, Gardner S, Garraway B, Gauguet A, Gerlach S, Gersemann M, Gibson V, Giese E, Giudice GF, Glasbrenner EP, Gündoğan M, Haehnelt M, Hakulinen T, Hammerer K, Hanımeli ET, Harte T, Hawkins L, Hees A, Heise J, Henderson VA, Herrmann S, Hird TM, Hogan JM, Holst B, Holynski M, Hussain K, Janson G, Jeglič P, Jelezko F, Kagan M, Kalliokoski M, Kasevich M, Kehagias A, Kilian E, Koley S, Konrad B, Kopp J, Kornakov G, Kovachy T, Krutzik M, Kumar M, Kumar P, Lämmerzahl C, Landsberg G, Langlois M, Lanigan B, Lellouch S, Leone B, Poncin-Lafitte CL, Lewicki M, Leykauf B, Lezeik A, Lombriser L, Luis Lopez-Gonzalez J, Lopez Asamar E, Monjaraz CL, Luciano GG, Mahmoud MA, Maleknejad A, Krutzik M, Marteau J, Massonnet D, Mazumdar A, McCabe C, Meister M, Menu J, Messineo G, Micalizio S, Millington P, Milosevic M, Mitchell J, Montero M, Morley GW, Müller J, ioğlu ÖEM, Ni W-T, Noller J, Odžak S, Oi DKL, Omar Y, Pahl J, Paling S, Pandey S, Pappas G, Pareek V, Pasatembou E, Pelucchi E, Pereira dos Santos F, Piest B, Pikovski I, Pilaftsis A, Plunkett R, Poggiani R, Prevedelli M, Pupet al., 2024,

    Terrestrial very-long-baseline atom interferometry: workshop summary

    , AVS Quantum Science, Vol: 6, ISSN: 2639-0213

    This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.
  • Journal article
    Shi D, Shang F, Chen B, Expert P, Lü L, Stanley HE, Lambiotte R, Evans TS, Li R, Shang F, Chen B, Expert P, Lü L, Yang A, Stanley HE, Lambiotte R, Evans TS, Li Ret al., 2024,

    Local dominance unveils clusters in networks

    , Communications Physics, Vol: 7, ISSN: 2399-3650

    Clusters or communities can provide a coarse-grained description of complex systems at multiple scales, but their detection remains challenging in practice. Community detection methods often define communities as dense subgraphs, or subgraphs with few connections in-between, via concepts such as the cut, conductance, or modularity. Here we consider another perspective built on the notion of local dominance, where low-degree nodes are assigned to the basin of influence of high-degree nodes, and design an efficient algorithm based on local information. Local dominance gives rises to community centers, and uncovers local hierarchies in the network. Community centers have a larger degree than their neighbors and are sufficiently distant from other centers. The strength of our framework is demonstrated on synthesized and empirical networks with ground-truth community labels. The notion of local dominance and the associated asymmetric relations between nodes are not restricted to community detection, and can be utilised in clustering problems, as we illustrate on networks derived from vector data.
  • Journal article
    Hanany A, Kumaran G, Li C, Liu D, Sperling Met al., 2024,

    Actions on the quiver: discrete quotients on the Coulomb branch

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Hull CM, 2024,

    Magnetic charges for the graviton

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Conference paper
    Tseytlin AA, 2024,

    AdS/CFT, Wilson loops and M2-branes

    We discuss 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 show that the quantum M2 brane partition function expanded near the corresponding classical solution matches the localization predictions on the gauge theory side in the case of BPS Wilson loop expectation value and instanton corrections to free energy.
  • Journal article
    Albertini E, Dowker F, Nasiri A, Zalel Set al., 2024,

    In-in correlators and scattering amplitudes on a causal set

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 109, ISSN: 1550-2368

    Causal set theory is an approach to quantum gravity in which spacetime is fundamentally discrete at the Planck scale and takes the form of an irregular Lorentzian lattice, or “causal set,” from which continuum spacetime emerges in a large-scale (low-energy) approximation. In this work, we present new developments in the framework of interacting quantum field theory on causal sets. We derive a diagrammatic expansion for in-in correlators in local scalar field theories with finite polynomial interactions. We outline how these same correlators can be computed using the double-path integral, which acts as a generating functional for the in-in correlators. We modify the in-in generating functional to obtain a generating functional for in-out correlators. We define a notion of scattering amplitudes on causal sets with noninteracting past and future regions and verify that they are given by 𝑆-matrix elements (matrix elements of the time-evolution operator). We describe how these formal developments can be implemented to compute early Universe observables under the assumption that spacetime is fundamentally discrete.

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