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  • Journal article
    Mkrtchyan K, Svazas M, 2022,

    Solutions in Nonlinear Electrodynamics and their double copy regular black holes

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Hoare B, Seibold FK, Tseytlin AA, 2022,

    Integrable supersymmetric deformations of AdS(3)x S(3)x T-4

    , The Journal of High Energy Physics, Vol: 2022, Pages: 1-39, ISSN: 1029-8479

    We construct a family of type IIB string backgrounds that are deformations of AdS3 × S3 × T4 with a “squashed” AdS3 × S3 metric supported by a combination of NSNS and RR fluxes. They have global SU(1, 1) × SU(2) symmetry, regular curvature, constant dilaton and preserve 8 supercharges. Upon compactification to 4 dimensions they reduce to N = 2 supersymmetric AdS2 × S2 solutions with electric and magnetic Maxwell fluxes. These type IIB supergravity solutions can be found from the undeformed AdS3 × S3 × T4 background by a combination of T-dualities and S-duality. In contrast to T-duality, S-duality transformations of a type IIB supergravity background do not generally preserve the classical integrability of the corresponding Green-Schwarz superstring sigma model. Nevertheless, we show that integrability is preserved in the present case. Indeed, we find that these backgrounds can be obtained, up to T-dualities, from an integrable inhomogeneous Yang-Baxter deformation (with unimodular Drinfel’d-Jimbo R-matrix) of the original AdS3 × S3 supercoset model.
  • Journal article
    Hoare B, Seibold FK, Tseytlin AA, 2022,

    Integrable supersymmetric deformations of AdS<inf>3</inf> × S<sup>3</sup> × T<sup>4</sup>

    , Journal of High Energy Physics, Vol: 2022

    We construct a family of type IIB string backgrounds that are deformations of AdS3× S3× T4 with a “squashed” AdS3× S3 metric supported by a combination of NSNS and RR fluxes. They have global SU(1, 1) × SU(2) symmetry, regular curvature, constant dilaton and preserve 8 supercharges. Upon compactification to 4 dimensions they reduce to N = 2 supersymmetric AdS2× S2 solutions with electric and magnetic Maxwell fluxes. These type IIB supergravity solutions can be found from the undeformed AdS3× S3× T4 background by a combination of T-dualities and S-duality. In contrast to T-duality, S-duality transformations of a type IIB supergravity background do not generally preserve the classical integrability of the corresponding Green-Schwarz superstring sigma model. Nevertheless, we show that integrability is preserved in the present case. Indeed, we find that these backgrounds can be obtained, up to T-dualities, from an integrable inhomogeneous Yang-Baxter deformation (with unimodular Drinfel’d-Jimbo R-matrix) of the original AdS3× S3 supercoset model.
  • Journal article
    Bourget A, Grimminger JF, Hanany A, Zhong Zet al., 2022,

    The Hasse diagram of the moduli space of instantons

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Gerhardinger M, Giblin JTJJ, Tolley AJ, Trodden Met al., 2022,

    Well-posed UV completion for simulating scalar Galileons

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 106, Pages: 1-10, ISSN: 1550-2368

    The Galileon scalar field theory is a prototypical example of an effective field theory that exhibits the Vainshtein screening mechanism, which is incorporated into many extensions to Einstein gravity. The Galileon describes the helicity-zero mode of gravitational radiation, the presence of which has significant implications for predictions of gravitational waves from orbiting objects and for tests of gravity sensitive to additional polarizations. Because of the derivative nature of their interactions, Galileons are superficially not well posed as effective field theories. Although this property is properly understood merely as an artifact of the effective field theory truncation, and is not theoretically worrisome, at the practical level it nevertheless renders numerical simulation highly problematic. Notwithstanding, previous numerical approaches have successfully evolved the system for reasonable initial data by slowly turning on the interactions. We present here two alternative approaches to improving numerical stability in Galileon numerical simulations. One of these is a minor modification of previous approaches, which introduces a low-pass filter that amounts to imposing a UV cutoff together with a relaxation method of turning on interactions. The second approach amounts to constructing a (numerical) UV completion for which the dynamics of the high momentum modes is under control and for which it is unnecessary to slowly turn on nonlinear interactions. We show that numerical simulations of the UV theory successfully reproduce the correct Galileon dynamics at low energies, consistent with the low-pass filter method and with previous numerical simulations.
  • Journal article
    Acharya B, Alexandre J, Benes P, Bergmann B, Bertolucci S, Bevan A, Bhattacharyya R, Branzas H, Burian P, Campbell M, Cecchini S, Cho YM, de Montigny M, De Roeck A, Ellis JR, ElSawy M, Fairbairn M, Felea D, Frank M, Hays J, Hirt AM, Hung PQ, Janecek J, Kalliokoski M, Korzenev A, Lacarrere DH, Leroy C, Levi G, Lionti A, Margiotta A, Maselek R, Maulik A, Mauri N, Mavromatos NE, Musumeci E, Mieskolainen M, Millward L, Mitsou VA, Orava R, Ostrovskiy I, Ouimet P-P, Papavassiliou J, Parker B, 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, Santra A, Sarkar S, Semenoff G, Shaa A, Sirri G, Sliwa K, Soluk R, Spurio M, Staelens M, Suk M, Tenti M, Togo V, Upreti A, Vento V, Vives Oet al., 2022,

    Search for highly-ionizing particles in <i>pp</i> collisions at the LHC's Run-1 using the prototype MoEDAL detector

    , EUROPEAN PHYSICAL JOURNAL C, Vol: 82, ISSN: 1434-6044
  • Journal article
    Avetisyan Z, Evnin O, Mkrtchyan K, 2022,

    Nonlinear (chiral) <i>p</i>-form electrodynamics

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Working paper
    Cheung KCM, Fry JHT, Gauntlett JP, Sparks Jet al., 2022,

    M5-branes wrapped on four-dimensional orbifolds

    , Publisher: ArXiv

    We construct supersymmetric $AdS_3$ solutions of $D=11$ supergravity, dual to$d=2$, $\mathcal{N}=(0,2)$ SCFTs, that are associated with M5-branes wrappingtwo different four-dimensional orbifolds. In one case the orbifold is a spindlefibred over another spindle, while in the other it is a spindle fibred over aRiemann surface with genus $g>1$. We show that the central charges of the $d=2$SCFTs calculated from the gravity solutions agree with field theorycomputations using anomaly polynomials. The new $D=11$ solutions are obtainedafter constructing a new consistent Kaluza-Klein truncation of maximal $D=7$gauged supergravity reduced on a spindle down to $D=5$ minimal gaugedsupergravity.
  • Journal article
    Bourget A, Grimminger JF, Hanany A, Kalveks R, Zhong Zet al., 2022,

    Higgs branches of U/SU quivers via brane locking

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Baker T, Calcagni G, Chen A, Fasiello M, Lombriser L, Martinovic K, Pieroni M, Sakellariadou M, Tasinato G, Bertacca D, Saltas IDet al., 2022,

    Measuring the propagation speed of gravitational waves with LISA

    , JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, ISSN: 1475-7516
  • Journal article
    Bourget A, Dancer A, Grimminger JF, Hanany A, Zhong Zet al., 2022,

    Partial implosions and quivers

    , JOURNAL OF HIGH ENERGY PHYSICS, ISSN: 1029-8479
  • Journal article
    Erickson CW, Leung R, Stelle KS, 2022,

    Higgs Effect Without Lunch

    , Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, ISSN: 1364-503X

    Reduction in effective spacetime dimensionality can occur in field-theorymodels more general than the widely studied dimensional reductions based ontechnically consistent truncations. Situations where wavefunction factorsdepend nontrivially on coordinates transverse to the effective lower dimensioncan give rise to unusual patterns of gauge symmetry breaking. Leading-ordergauge modes can be left massless, but naturally occurring Stueckelberg modescan couple importantly at quartic order and higher, thus generating a "covert"pattern of gauge symmetry breaking. Such a situation is illustrated in afive-dimensional model of scalar electrodynamics in which one spatial dimensionis taken to be an interval with Dirichlet/Robin boundary conditions on opposingends. This simple model illuminates a mechanism which also has been found ingravitational braneworld scenarios.
  • Journal article
    Evans T, Chen B, Evans TS, Chen Bet al., 2022,

    Linking the network centrality measures closeness and degree

    , Communications Physics, Vol: 5, Pages: 1-11, ISSN: 2399-3650

    Measuring the importance of nodes in a network with a centrality measure is an core task in any network application. There many measures available and it is speculated that many encode similar information. We give an explicit non-linear relationship between two of the most popular measures of node centrality: degree and closeness. Based on a shortest-path tree approximation, we give an analytic derivation that shows the inverse ofcloseness is linearly dependent on the logarithm of degree. We show that our hypothesis works well for a range of networks produced from stochastic network models and for networks derived from 130 real-world data sets. We connect our results with previous results for other network distance scales such as average distance. Our results imply that measuring closeness is broadly redundant unless our relationship is used to remove the dependence on degree from closeness. The success of our relationship suggests that most networks can be approximated by shortest-path spanning trees which are all statistically similar two or more steps away from their root nodes.
  • Journal article
    Mylova M, Moschou M, Afshordi N, Magueijo Jet al., 2022,

    Non-gaussian signatures of a thermal big bang

    , Journal of Cosmology and Astroparticle Physics, Vol: 2022, Pages: 1-25, ISSN: 1475-7516

    What if Big Bang was hot from its very inception? This is possible in a bimetric theory where the source of fluctuations is thermal, requiring the model to live on a critical boundary in the space of parameters and can be realized when an anti-DBI brane moves within an EAdS2 ×E3 geometry. This setup renders the model unique, with sharp predictions for the scalar spectral index and its running. We investigate the non-Gaussian signatures of this thermal bimetric model, or "bi-thermal" for short. We adapt the standard calculation of non-Gaussianities for P(X,ϕ) models to the thermal nature of the model, emphasising how the bi-thermal peculiarities affect the calculation and alter results. This leads to precise predictions for the shape and amplitude of the three-point function of the bi-thermal model (at tree-level): flocalNL = -3/2 and fequilNL = -2 + 4 √(3)π/9 ≃ 0.4. We also discover a new shape of flattened non-gaussianity ∝ (k1 + k2 - k3)-3/2 + permutations, which is expected due to the excited thermal initial conditions. These results, along with our earlier predictions for the scalar power spectrum, provide sharp targets for the future generation of cosmological surveys.
  • Journal article
    Addazi A, Alvarez-Muniz J, Alves Batista R, Amelino-Camelia G, Antonelli V, Arzano M, Asorey M, Atteia J-L, Bahamonde S, Bajardi F, Ballesteros A, Baret B, Barreiros DM, Basilakos S, Benisty D, Birnholtz O, Blanco-Pillado JJ, Blas D, Bolmont J, Boncioli D, Bosso P, Calcagni G, Capozziello S, Carmona JM, Cerci S, Chernyakova M, Clesse S, Coelho JAB, Colak SM, Cortes JL, Das S, D'Esposito V, Demirci M, Di Luca MG, di Matteo A, Dimitrijevic D, Djordjevic G, Prester DD, Eichhorn A, Ellis J, Escamilla-Rivera C, Fabiano G, Franchino-Vinas SA, Frassino AM, Frattulillo D, Funk S, Fuster A, Gamboa J, Gent A, Gergely LA, Giammarchi M, Giesel K, Glicenstein J-F, Gracia-Bondia J, Gracia-Ruiz R, Gubitosi G, Guendelman E, Gutierrez-Sagredo I, Haegel L, Heefer S, Held A, Herranz FJ, Hinderer T, Illana JI, Ioannisian A, Jetzer P, Joaquim FR, Kampert K-H, Uysal AK, Katori T, Kazarian N, Kerszberg D, Kowalski-Glikman J, Kuroyanagi S, Lammerzahl C, Said JL, Liberati S, Lim E, Lobo IP, Lopez-Moya M, Luciano GG, Manganaro M, Marciano A, Martin-Moruno P, Martinez M, Martinez M, Martinez-Huerta H, Martinez-Mirave P, Masip M, Mattingly D, Mavromatos N, Mazumdar A, Mendez F, Mercati F, Micanovic S, Mielczarek J, Miller AL, Milosevic M, Minic D, Miramonti L, Mitsou VA, Moniz P, Mukherjee S, Nardini G, Navas S, Niechciol M, Nielsen AB, Obers NA, Oikonomou F, Oriti D, Paganini CF, Palomares-Ruiz S, Pasechnik R, Pasic V, de los Heros CP, Pfeifer C, Pieroni M, Piran T, Platania A, Rastgoo S, Relancio JJ, Reyes MA, Ricciardone A, Risse M, Rodriguez Frias MD, Rosati G, Rubiera-Garcia D, Sahlmann H, Sakellariadou M, Salamida F, Saridakis EN, Satunin P, Schiffer M, Schussler F, Sigl G, Sitarek J, Sola Peracaula J, Sopuerta CF, Sotiriou TP, Spurio M, Staicova D, Stergioulas N, Stoica S, Striskovic J, Stuttard T, Cerci DS, Tavakoli Y, Ternes CA, Terzic T, Thiemann T, Tinyakov P, Torri MDC, Tortola M, Trimarelli C, Trzesniewski T, Tureanu A, Urban FR, Vagenas EC, Vernieri D, Vitagliano V, Wallet J-C Zet al., 2022,

    Quantum gravity phenomenology at the dawn of the multi-messenger era-A review

    , PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, Vol: 125, ISSN: 0146-6410
  • Journal article
    Fumagalli J, Pieroni M, Renaux-Petel S, Witkowski LTet al., 2022,

    Detecting primordial features with LISA

    , JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, ISSN: 1475-7516
  • Journal article
    Adam A, Figueras P, Jacobson T, Wiseman Tet al., 2022,

    Rotating black holes in Einstein-aether theory

    , CLASSICAL AND QUANTUM GRAVITY, Vol: 39, ISSN: 0264-9381
  • Journal article
    Vasiliauskaite V, Evans TS, Expert P, 2022,

    Cycle analysis of directed acyclic graphs

    , Physica A: Statistical Mechanics and its Applications, Vol: 596, Pages: 1-22, ISSN: 0378-4371

    In this paper, we employ the decomposition of a directed network as an undirected graph plus its associated node meta-data to characterise the cyclic structure found in directed networks by finding a Minimal Cycle Basis of the undirected graph and augmenting its components with direction information. We show that only four classes of directed cycles exist, and that they can be fully distinguished by the organisation and number of source–sink node pairs and their antichain structure. We are particularly interested in Directed Acyclic Graphs and introduce a set of metrics that characterise the Minimal Cycle Basis using the Directed Acyclic Graphs meta-data information. In particular, we numerically show that transitive reduction stabilises the properties of Minimal Cycle Bases measured by the metrics we introduced while retaining key properties of the Directed Acyclic Graph. This makes the metrics a consistent characterisation of Directed Acyclic Graphs and the systems they represent. We measure the characteristics of the Minimal Cycle Bases of four models of transitively reduced Directed Acyclic Graphs and show that the metrics introduced are able to distinguish the models and are sensitive to their generating mechanisms.
  • Journal article
    Duff MJ, 2022,

    The conformal brane-scan: an update

    , JOURNAL OF HIGH ENERGY PHYSICS, Vol: 2022, ISSN: 1029-8479

    Generalizing the The Membrane at the End of the Universe, a 1987 paper Supersingletons by Blencowe and the author conjectured the existence of BPS p-brane configurations (p = 2, 3, 4, 5) and corresponding CFTs on the boundary of anti-de Sitter space with symmetries appearing in Nahm’s classification of superconformal algebras: OSp(N|4) N = 8, 4, 2, 1; SU(2, 2|N) N = 4, 2, 1; F 2(4); OSp(8∗|N), N = 4, 2. This correctly predicted the D3-brane with SU(2, 2|4) on AdS5 × S5 and the M5-brane with OSp(8∗|4) on AdS7 × S4, in addition to the known M2-brane with OSp(8|4) on AdS4 × S7. However, finding non-singular AdS solutions matching the other symmetries was less straightforward. Here we perform a literature search and confirm that all of the empty slots have now been filled, thanks to a number of extra ingredients including warped products and massive Type IIA. Orbifolds, orientifolds and S-folds also play a part providing examples not predicted: SU(2, 2|3), OSp(3|4), OSp(5|4) and OSp(6|4) but not OSp(7|4). We also examine the status of p = (0, 1) configurations.
  • Journal article
    Josse G, Malek E, Petrini M, Waldram Det al., 2022,

    The higher-dimensional origin of five-dimensional N=2 gauged supergravities

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

    Using exceptional generalised geometry, we classify which five-dimensional N = 2 gauged supergravities can arise as a consistent truncation of 10-/11-dimensional supergravity. Exceptional generalised geometry turns the classification into an algebraic problem of finding subgroups GS ⊂ USp(8) ⊂ E6(6) that preserve exactly two spinors. Moreover, the intrinsic torsion of the GS structure must contain only constant singlets under GS, and these, in turn, determine the gauging of the five-dimensional theory. The resulting five-dimensional theories are strongly constrained: their scalar manifolds are necessarily symmetric spaces and only a small number of matter multiplets can be kept, which we completely enumerate. We also determine the largest reductive and compact gaugings that can arise from consistent truncations.
  • Journal article
    Ashmore A, Petrini M, Tasker EL, Waldram Det al., 2022,

    Exactly marginal deformations and their supergravity duals

    , Physical Review Letters, Vol: 128, Pages: 1-6, ISSN: 0031-9007

    We study the space of supersymmetric AdS5 solutions of type IIB supergravity corresponding to the conformal manifold of the dual N=1 conformal field theory. We show that the background geometry naturally encodes a generalized holomorphic structure, dual to the superpotential of the field theory, with the existence of the full solution following from a continuity argument. In particular, this work allows us to address the long-standing problem of finding the gravity dual of the generic N=1 deformations of N=4 conformal field theory: even if we are not able to give it in a fully explicit form, we provide a proof-of-existence of the supergravity solution. Using this formalism, we derive a new result for the Hilbert series of the deformed field theories.
  • Journal article
    Roberts MM, Wiseman T, 2022,

    Curved-space Dirac description of elastically deformed monolayer graphene is generally incorrect

    , PHYSICAL REVIEW B, Vol: 105, ISSN: 2469-9950
  • Journal article
    AbdusSalam SS, Agocs FJ, Allanach BC, Athron P, Balazs C, Bagnaschi E, Bechtle P, Buchmueller O, Beniwal A, Bhom J, Bloor S, Bringmann T, Buckley A, Butter A, Camargo-Molina JE, Chrzaszcz M, Conrad J, Cornell JM, Danninger M, de Blas J, De Roeck A, Desch K, Dolan M, Dreiner H, Eberhardt O, Ellis J, Ben F, Fedele M, Flaecher H, Fowlie A, Gonzalo TE, Grace P, Hamer M, Handley W, Harz J, Heinemeyer S, Hoof S, Hotinli S, Jackson P, Kahlhoefer F, Kowalska K, Kraemer M, Kvellestad A, Martinez ML, Mahmoudi F, Martinez Santos D, Martinez GD, Mishima S, Olive K, Paul A, Prim MT, Porod W, Raklev A, Renk JJ, Rogan C, Roszkowski L, de Austri RR, Sakurai K, Scaffidi A, Scott P, Sessolo EM, Stefaniak T, Stoecker P, Su W, Trojanowski S, Trotta R, Tsai Y-LS, Van den Abeele J, Valli M, Vincent AC, Weiglein G, White M, Wienemann P, Wu L, Zhang Yet al., 2022,

    Simple and statistically sound recommendations for analysing physical theories

    , Reports on Progress in Physics, Vol: 85, ISSN: 0034-4885

    Physical theories that depend on many parameters or are tested against data from many different experiments pose unique challenges to statistical inference. Many models in particle physics, astrophysics and cosmology fall into one or both of these categories. These issues are often sidestepped with statistically unsound ad hoc methods, involving intersection of parameter intervals estimated by multiple experiments, and random or grid sampling of model parameters. Whilst these methods are easy to apply, they exhibit pathologies even in low-dimensional parameter spaces, and quickly become problematic to use and interpret in higher dimensions. In this article we give clear guidance for going beyond these procedures, suggesting where possible simple methods for performing statistically sound inference, and recommendations of readily-available software tools and standards that can assist in doing so. Our aim is to provide any physicists lacking comprehensive statistical training with recommendations for reaching correct scientific conclusions, with only a modest increase in analysis burden. Our examples can be reproduced with the code publicly available at Zenodo.
  • Working paper
    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, Luca VD, Pozzo WD, Desjacques V, Dimastrogiovanni E, Dorsch GC, Ezquiaga JM, Fasiello M, Figueroa DG, Flauger R, Franciolini G, Frusciante N, Fumagalli J, Garcia-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, Sopuerta CF, Tereno I, Tolley A, Urrestilla J, Vagenas EC, Vis JVD, Weygaert RVD, Wardell B, Weiet al., 2022,

    Cosmology with the Laser Interferometer Space Antenna

    , Publisher: ArXiv

    The Laser Interferometer Space Antenna (LISA) has two scientific objectivesof cosmological focus: to probe the expansion rate of the universe, and tounderstand stochastic gravitational-wave backgrounds and their implications forearly universe and particle physics, from the MeV to the Planck scale. However,the range of potential cosmological applications of gravitational waveobservations extends well beyond these two objectives. This publicationpresents a summary of the state of the art in LISA cosmology, theory andmethods, and identifies new opportunities to use gravitational waveobservations by LISA to probe the universe.
  • Journal article
    Leung JS-Y, Hartley J, Nagy JM, Netterfield CB, Shariff JA, Ade PAR, Amiri M, Benton SJ, Bergman AS, Bihary R, Bock JJ, Bond JR, Bonetti JA, Bryan SA, Chiang HC, Contaldi CR, Dore O, Duivenvoorden AJ, Eriksen HK, Farhang M, Filippini JP, Fraisse AA, Freese K, Galloway M, Gambrel AE, Gandilo NN, Ganga K, Gualtieri R, Gudmundsson JE, Halpern M, Hasselfield M, Hilton G, Holmes W, Hristov VV, Huang Z, Irwin KD, Jones WC, Karakci A, Kuo CL, Kermish ZD, Li S, Mak DSY, Mason P, Megerian K, Moncelsi L, Morford TA, Nolta M, Osherson B, Padilla IL, Racine B, Rahlin AS, Reintsema C, Ruhl JE, Runyan MC, Ruud TM, Shaw EC, Shiu C, Soler JD, Song X, Trangsrud A, Tucker C, Tucker RS, Turner AD, van der List JF, Weber AC, Wehus IK, Wen S, Wiebe D, Young EYet al., 2022,

    A Simulation-based Method for Correcting Mode Coupling in CMB Angular Power Spectra

    , ASTROPHYSICAL JOURNAL, Vol: 928, ISSN: 0004-637X
  • Journal article
    Bao J, Hanany A, He YH, Hirst Eet al., 2022,

    Some Open Questions in Quiver Gauge Theory

    , Proyecciones, Vol: 41, Pages: 355-386, ISSN: 0716-0917

    Quivers, gauge theories and singular geometries are of great interest in both mathematics and physics. In this note, we collect a few open questions which have arisen in various recent works at the intersection between gauge theories, representation theory, and algebraic geometry. The questions originate from the study of supersymmetric gauge theories in different dimensions with different supersymmetries. Although these constitute merely the tip of a vast iceberg, we hope this guide can give a hint of possible directions in future research.
  • Journal article
    de Rham C, Tolley AJ, Zhang J, 2022,

    Causality constraints on gravitational effective field theories

    , Physical Review Letters, Vol: 128, Pages: 1-6, ISSN: 0031-9007

    We consider the effective field theory of gravity around black holes, and show that the coefficients of the dimension-8 operators are tightly constrained by causality considerations. Those constraints are consistent with—but tighter than—previously derived causality and positivity bounds and imply that the effects of one of the dimension-8 operators by itself cannot be observable while remaining consistent with causality. We then establish in which regime one can expect the generic dimension-8 and lower order operators to be potentially observable while preserving causality, providing a theoretical prior for future observations. We highlight the importance of “infrared causality” and show that the requirement of “asymptotic causality” or net (sub)luminality would fail to properly diagnose violations of causality.
  • Journal article
    Borsten L, Marrani A, Pope CN, Stelle Ket al., 2022,

    Introduction to the special issue dedicated to Michael J. Duff FRS on the occasion of his 70th birthday

    , PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, Vol: 478, ISSN: 1364-5021
  • Journal article
    Collaboration SPIDER, Ade PAR, Amiri M, Benton SJ, Bergman AS, Bihary R, Bock JJ, Bond JR, Bonetti JA, Bryan SA, Chiang HC, Contaldi CR, Doré O, Duivenvoorden AJ, Eriksen HK, Farhang M, Filippini JP, Fraisse AA, Freese K, Galloway M, Gambrel AE, Gandilo NN, Ganga K, Gualtieri R, Gudmundsson JE, Halpern M, Hartley J, Hasselfield M, Hilton G, Holmes W, Hristov VV, Huang Z, Irwin KD, Jones WC, Karakci A, Kuo CL, Kermish ZD, Leung JS-Y, Li S, Mak DSY, Mason PV, Megerian K, Moncelsi L, Morford TA, Nagy JM, Netterfield CB, Nolta M, O'Brient R, Osherson B, Padilla IL, Racine B, Rahlin AS, Reintsema C, Ruhl JE, Runyan MC, Ruud TM, Shariff JA, Shaw EC, Shiu C, Soler JD, Song X, Trangsrud A, Tucker C, Tucker RS, Turner AD, List JFVD, Weber AC, Wehus IK, Wen S, Wiebe DV, Young EYet al., 2022,

    A constraint on primordial B-modes from the first flight of the spider balloon-borne telescope

    , The Astrophysical Journal: an international review of astronomy and astronomical physics, Vol: 927, Pages: 1-26, ISSN: 0004-637X

    We present the first linear polarization measurements from the 2015long-duration balloon flight of SPIDER, an experiment designed to map thepolarization of the cosmic microwave background (CMB) on degree angular scales.Results from these measurements include maps and angular power spectra fromobservations of 4.8% of the sky at 95 and 150 GHz, along with the results ofinternal consistency tests on these data. While the polarized CMB anisotropyfrom primordial density perturbations is the dominant signal in this region ofsky, Galactic dust emission is also detected with high significance; Galacticsynchrotron emission is found to be negligible in the SPIDER bands. We employtwo independent foreground-removal techniques in order to explore thesensitivity of the cosmological result to the assumptions made by each. Theprimary method uses a dust template derived from Planck data to subtract theGalactic dust signal. A second approach, employing a joint analysis of SPIDERand Planck data in the harmonic domain, assumes a modified-blackbody model forthe spectral energy distribution of the dust with no constraint on its spatialmorphology. Using a likelihood that jointly samples the template amplitude and$r$ parameter space, we derive 95% upper limits on the primordialtensor-to-scalar ratio from Feldman-Cousins and Bayesian constructions, finding$r<0.11$ and $r<0.19$, respectively. Roughly half the uncertainty in $r$derives from noise associated with the template subtraction. New data at 280GHz from SPIDER's second flight will complement the Planck polarization maps,providing powerful measurements of the polarized Galactic dust emission.
  • Journal article
    Chen CY-R, de Rham C, Margalit A, Tolley AJet al., 2022,

    A cautionary case of casual causality

    , The Journal of High Energy Physics, Vol: 25, Pages: 1-40, ISSN: 1029-8479

    We distinguish between the notions of asymptotic causality and infrared causality for gravitational effective field theories, and show that the latter gives constraints consistent with gravitational positivity bounds. We re-explore the scattering of gravitational waves in a spherically symmetric background in the EFT of gravity in D ≥ 5, for which the leading-order correction to Einstein gravity is determined by the Gauss-Bonnet operator. We reproduce the known result that the truncated effective theory exhibits apparent time advances relative to the background geometry for specific polarisations, which naively signal a violation of causality. We show that by properly identifying the regime of validity of the effective theory, the apparent time advance can be shown to be unresolvable. To illustrate this, we identify specific higher-dimension operators in the EFT expansion which become large for potentially resolvable time advances, rendering the EFT expansion invalid. Our results demonstrate how staying within the confines of the EFT, neither infrared nor asymptotic causality are ever violated for Einstein-Gauss-Bonnet gravity, no matter how low the scale, and furthermore its causality can be understood without appealing to a precise UV completion such as string theory.

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