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  • 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

    The stochastic spectral expansion method offers a simple framework for calculations in de Sitter spacetimes. We show how to extend its reach to metastable vacuum states, both in the case when the potential is bounded from below, and when it is unbounded from below and therefore no stable vacuum state exists. In both cases, the decay rate of the metastable vacuum is given by the lowest nonzero eigenvalue associated to the Fokker–Planck equation. We show how the corresponding eigenfunction determines the field probability distribution which can be used to compute correlation functions and other observables in the metastable vacuum state.
  • 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
    Mkrtchyan K, Valach F, 2023,

    Democratic actions for type II supergravities

    , 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
    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
  • Journal article
    Boido A, Gauntlett JP, Martelli D, Sparks Jet al., 2023,

    Entropy functions for accelerating black holes

    , Physical Review Letters, Vol: 130, ISSN: 0031-9007

    We introduce an entropy function for supersymmetric accelerating black holes in four-dimensional anti–de Sitter space that uplift on general Sasaki-Einstein manifolds X7 to solutions of M theory. This allows oneto compute the black hole entropy without knowing the explicit solutions. A dual holographic microstatecounting would follow from computing certain supersymmetric partition functions of Chern-Simonsmatter theories compactified on a spindle. We make a general prediction for a class of such partitionfunctions in terms of “blocks,” with each block being constructed from the partition function on a threesphere
  • Journal article
    Aharony O, Chester SM, Sheaffer T, Urbach EYet al., 2023,

    Explicit holography for vector models at finite N, volume and temperature

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>In previous work we constructed an explicit mapping between large <jats:italic>N</jats:italic> vector models (free or critical) in <jats:italic>d</jats:italic> dimensions and a non-local high-spin gravity theory on <jats:italic>AdS</jats:italic><jats:sub><jats:italic>d</jats:italic>+1</jats:sub>, such that the gravitational theory reproduces the field theory correlation functions order by order in 1<jats:italic>/N</jats:italic>. In this paper we discuss three aspects of this mapping. First, our original mapping was not valid non-perturbatively in 1<jats:italic>/N</jats:italic>, since it did not include non- local correlations between the gravity fields which appear at finite <jats:italic>N</jats:italic>. We show that by using a bi-local <jats:italic>G</jats:italic> − Σ type formalism similar to the one used in the SYK model, we can construct an exact mapping to the bulk that is valid also at finite <jats:italic>N</jats:italic>. The theory in the bulk contains additional auxiliary fields which implement the finite <jats:italic>N</jats:italic> constraints. Second, we discuss the generalization of our mapping to the field theory on <jats:italic>S</jats:italic><jats:sup><jats:italic>d</jats:italic></jats:sup>, and in particular how the sphere free energy matches exactly between the two sides, and how the mapping can be consistently regularized. Finally, we discuss the field theory at finite temperature, and show that the low-temperature phase of the vector models can be mapped to a high-spin gravity theory on thermal AdS space.</jats:p>
  • Journal article
    Baker T, Barausse E, Chen A, de Rham C, Pieroni M, Tasinato Get al., 2023,

    Testing gravitational wave propagation with multiband detections

    , Journal of Cosmology and Astroparticle Physics, Vol: 2023, Pages: 1-21, ISSN: 1475-7516

    Effective field theories (EFT) of dark energy (DE) — built to parameterise the properties of DE in an agnostic manner — are severely constrained by measurements of the propagation speed of gravitational waves (GW). However, GW frequencies probed by ground-based interferometers lie around the typical strong coupling scale of the EFT, and it is likely that the effective description breaks down before even reaching that scale. We discuss how this leaves the possibility that an appropriate ultraviolet completion of DE scenarios, valid at scales beyond an EFT description, can avoid present constraints on the GW speed. Instead, additional constraints in the lower frequency LISA band would be harder to escape, since the energies involved are orders of magnitude lower. By implementing a method based on GW multiband detections, we show indeed that a single joint observation of a GW150914-like event by LISA and a terrestrial interferometer would allow one to constrain the speed of light and gravitons to match to within 10-15. Multiband GW observations can therefore firmly constrain scenarios based on the EFT of DE, in a robust and unambiguous way.
  • Journal article
    Gielen S, Magueijo J, 2023,

    Quantum resolution of the cosmological singularity without new physics

    , EPL, Vol: 141, ISSN: 0302-072X

    We study a quantum Hot Big Bang in the connection representation, with a matter constant of motion m whose conjugate defines time. Superpositions in m induce a unitary inner product. The wave function reveals a resolution of the singularity problem without new physics or supplementary boundary conditions. Backtracking in time, the probability peak eventually halts at a maximum curvature, its height dropping thereafter while a symmetric contracting peak rises. The Big Bang is replaced by a superposition of contracting and expanding regular Universes. We contrast these findings with the situation in the metric representation, where boundary conditions at the singularity are needed for unitary evolution.
  • Journal article
    Cabass G, Jazayeri S, Pajer E, Stefanyszyn Det al., 2023,

    Parity violation in the scalar trispectrum: no-go theorems and yes-go examples

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

    We derive a set of no-go theorems and yes-go examples for the parity-odd primordial trispectrum of curvature perturbations. We work at tree-level in the decoupling limit of the Effective Field Theory of Inflation and assume scale invariance and a Bunch-Davies vacuum. We show that the parity-odd scalar trispectrum vanishes in the presence of any number of scalar fields with arbitrary mass and any parity-odd scalar correlator vanishes in the presence of any number of spinning fields with massless de Sitter mode functions, in agreement with the findings of Liu, Tong, Wang and Xianyu [1]. The same is true for correlators with an odd number of conformally-coupled external fields. We derive these results using both the (boostless) cosmological bootstrap, in particular the Cosmological Optical Theorem, and explicit perturbative calculations. We then discuss a series of yes-go examples by relaxing the above assumptions one at the time. In particular, we provide explicit results for the parity-odd trispectrum for (i) violations of scale invariance in single-clock inflation, (ii) the modified dispersion relation of the ghost condensate (non-Bunch-Davies vacuum), and (iii) interactions with massive spinning fields. Our results establish the parity-odd trispectrum as an exceptionally sensitive probe of new physics beyond vanilla inflation.
  • Journal article
    Isichei R, Magueijo J, 2023,

    Minisuperspace quantum cosmology from the Einstein-Cartan path integral

    , Physical Review D, Vol: 107, Pages: 1-8, ISSN: 2470-0010

    We derive the fixed-Λ and unimodular propagators using the path integral formalism as applied to the Einstein-Cartan action. The simplicity of the action (which is linear in the lapse function) allows for an exact integration starting from the lapse function and the enforcement of the Hamiltonian constraint, leading to a product of Chern-Simons states if the connection is fixed at the endpoints. No saddle point approximation is needed. Should the metric be fixed at the endpoints, then, depending on the contour chosen for the connection, Hartle-Hawking or Vilenkin propagators are obtained. Thus, in this approach one trades a choice of contour in the lapse function for one in the connection, where appropriate. The unimodular propagators are also trivial to obtain via the path integral, and the previously derived expressions are recovered.
  • Journal article
    Chester SM, 2023,

    Bootstrapping 4d $$ \mathcal{N} $$ = 2 gauge theories: the case of SQCD

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>We derive exact relations between certain integrals of the conserved flavor current four point function in 4d <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> = 2 conformal field theories (CFTs) and derivatives of the mass deformed sphere free energy, which can be computed exactly for gauge theories using supersymmetric localization. For conformal gauge theories with flavor groups of rank greater than one, there are at least two such integrated constraints, which can then be combined with the numerical conformal bootstrap to bound CFT data as a function of the complexified gauge coupling <jats:italic>τ</jats:italic>. We apply this strategy to the case of SU(2) conformal SQCD with flavor group SO(8), where we compute bounds on unprotected scaling dimensions as a function of <jats:italic>τ</jats:italic> that match the free theory limit, and exhibit the expected mixing between the action of the SL(2<jats:italic>,</jats:italic> ℤ) duality group and SO(8) triality.</jats:p>
  • Journal article
    Gielen S, Magueijo J, 2023,

    Quantum analysis of the recent cosmological bounce in the comoving Hubble length

    , Physical Review D, Vol: 107, Pages: 1-16, ISSN: 2470-0010

    We formulate the transition from decelerated to accelerated expansion as a bounce in connection space and study its quantum cosmology, knowing that reflections are notorious for bringing quantum effects to the fore. We use a formalism for obtaining a time variable via the demotion of the constants of nature to integration constants, and focus on a toy universe containing only radiation and a cosmological constant Λ for simplicity. We find that, beside the usual factor-ordering ambiguities, there is an ambiguity in the order of the quantum equation, leading to two distinct theories: one second order, and one first order. In both cases two time variables may be defined, conjugate to Λ and the radiation constant of motion. We make little headway with the second-order theory, but are able to produce solutions to the first-order theory. They exhibit the well-known “ringing” whereby incident and reflected waves interfere, leading to oscillations in the probability distribution even for well-peaked wave packets. We also examine in detail the probability measure within the semiclassical approximation. Close to the bounce, the probability distribution becomes double peaked, with one peak following a trajectory close to the classical limit but with a Hubble parameter slightly shifted downwards, and the other with a value of b stuck at its minimum. An examination of the effects still closer to the bounce, and within a more realistic model involving matter and Λ, is left to future work.
  • Journal article
    Beccaria M, Korchemsky GP, Tseytlin AA, 2023,

    Exact strong coupling results in N=2 Sp(2N) superconformal gauge theory from localization

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

    We apply the localization technique to compute the free energy on four-sphere and the circular BPS Wilson loop in the four-dimensional N = ∈ superconformal Sp(2N) gauge theory containing vector multiplet coupled to four hypermultiplets in fundamental representation and one hypermultiplet in rank-2 antisymmetric representation. This theory is unique among similar N = ∈ superconformal models that are planar-equivalent to N = ∆ SYM in that the corresponding localization matrix model has the interaction potential containing single-trace terms only. We exploit this property to show that, to any order in large N expansion and an arbitrary ’t Hooft coupling λ, the free energy and the Wilson loop satisfy Toda lattice equations. Solving these equations at strong coupling, we find remarkably simple expressions for these observables which include all corrections in 1/N and 1/√λ. We also compute the leading exponentially suppressed O(e-√λ) corrections and consider a generalization to the case when the fundamental hypermultiplets have a non-zero mass. The string theory dual of this N = ∈ gauge theory should be a particular orientifold of AdS5 × S5 type IIB string and we discuss the string theory interpretation of the obtained strong-coupling results.
  • Journal article
    Chester SM, Dempsey R, Pufu SS, 2023,

    Bootstrapping $$ \mathcal{N} $$ = 4 super-Yang-Mills on the conformal manifold

    , Journal of High Energy Physics, Vol: 2023

    <jats:title>A<jats:sc>bstract</jats:sc> </jats:title><jats:p>We combine supersymmetric localization results with numerical bootstrap techniques to compute upper bounds on the low-lying CFT data of <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> = 4 super-Yang-Mills theory as a function of the complexified gauge coupling <jats:italic>τ</jats:italic>. In particular, from the stress tensor multiplet four-point function, we extract the scaling dimension of the lowest-lying unprotected scalar operator and its OPE coefficient. While our method can be applied in principle to any gauge group <jats:italic>G</jats:italic>, we focus on <jats:italic>G</jats:italic> = SU(2) and SU(3) for simplicity. At weak coupling, the upper bounds we find are very close to the corresponding four-loop results. We also give preliminary evidence that these upper bounds become small islands under reasonable assumptions.</jats:p>
  • Journal article
    Yan C, Barik A, Stanley S, Leung JS-Y, Mittelholz A, Johnson CL, Plesa A-C, Rivoldini Aet al., 2023,

    An Ancient Martian Dynamo Driven by Hemispheric Heating: Effect of Thermal Boundary Conditions

    , PLANETARY SCIENCE JOURNAL, Vol: 4
  • Journal article
    Bourget A, Grimminger JF, Hanany A, Sperling M, Zhong Zet al., 2023,

    Branes, quivers, and the affine Grassmannian

    , Advanced Studies in Pure Mathematics, Vol: 88, Pages: 331-435, ISSN: 0920-1971

    Brane systems provide a large class of gauge theories that arise in string theory. This paper demonstrates how such brane systems fit with a somewhat exotic geometric object, called the affine Grassmannian. This gives a strong motivation to study physical aspects of the affine Grassmannian. Explicit quivers are presented throughout the paper, and a quiver addition algorithm to generate the affine Grassmannian is introduced. An important outcome of this study is a set of quivers for new elementary slices.
  • Journal article
    Giardino S, Giusti A, Faraoni V, 2023,

    Thermal stability of stealth and de Sitter spacetimes in scalar-tensor gravity.

    , Eur Phys J C Part Fields, Vol: 83, ISSN: 1434-6044

    Stealth solutions of scalar-tensor gravity and less-known de Sitter spaces that generalize them are analyzed regarding their possible role as thermal equilibria at non-zero temperature in the new first-order thermodynamics of scalar-tensor gravity. No stable equilibria are found, further validating the special role of general relativity as an equilibrium state in the landscape of gravity theories, seen through the lens of first-order thermodynamics.
  • Journal article
    Cheung M-W, Dechant P-P, He Y-H, Heyes E, Hirst E, Li J-Ret al., 2023,

    Clustering cluster algebras with clusters

    , Advances in Theoretical and Mathematical Physics, Vol: 27, Pages: 797-828, ISSN: 1095-0761
  • Journal article
    Faraoni V, Giardino S, Giusti A, Vanderwee Ret al., 2023,

    Scalar field as a perfect fluid: thermodynamics of minimally coupled scalars and Einstein frame scalar-tensor gravity.

    , Eur Phys J C Part Fields, Vol: 83, ISSN: 1434-6044

    We revisit the analogy between a minimally coupled scalar field in general relativity and a perfect fluid, correcting previous identifications of effective temperature and chemical potential. This provides a useful complementary picture for the first-order thermodynamics of scalar-tensor gravity, paving the way for the Einstein frame formulation (which eluded previous attempts) and raises interesting questions to further develop the analogy.
  • Journal article
    Giusti A, Giardino S, Faraoni V, 2023,

    Past-directed scalar field gradients and scalar-tensor thermodynamics.

    , Gen Relativ Gravit, Vol: 55, ISSN: 0001-7701

    We refine and slightly enlarge the recently proposed first-order thermodynamics of scalar-tensor gravity to include gravitational scalar fields with timelike and past-directed gradients. The implications and subtleties arising in this situation are discussed and an exact cosmological solution of scalar-tensor theory in first-order thermodynamics is revisited in light of these results.
  • Journal article
    Cable A, Rajantie A, 2022,

    Second-order stochastic theory for self-interacting scalar fields in de Sitter spacetime

    , Physical Review D: Particles, Fields, Gravitation and Cosmology, Vol: 106, ISSN: 1550-7998

    We introduce a second-order stochastic effective theory for light scalar fields in de Sitter spacetime, extending the validity of the stochastic approach beyond the massless limit and demonstrating how it can be used to compute long-distance correlation functions nonperturbatively. The parameters of the second-order stochastic theory are determined from quantum field theory through a perturbative calculation, which is valid if the self-interaction parameter 𝜆 satisfies 𝜆 ≪𝑚²/𝐻², where 𝑚 is the scalar and 𝐻 is the Hubble rate. Therefore, it allows stronger self-interactions than conventional perturbation theory, which is limited to 𝜆 ≪𝑚⁴/𝐻⁴ by infrared divergences. We demonstrate the applicability of the second-order stochastic theory by comparing its results with perturbative quantum field theory and overdamped stochastic calculations, and discuss the prospects of improving its accuracy with a full one-loop calculation of its parameters.
  • Journal article
    Afshordi N, Magueijo J, 2022,

    Lower bound on the cosmological constant from the classicality of the early Universe

    , Physical Review D, Vol: 106, Pages: 1-10, ISSN: 2470-0010

    We use the quantum unimodular theory of gravity to relate the value of the cosmological constant, Λ, and the energy scale for the emergence of cosmological classicality. The fact that Λ and unimodular time are complementary quantum variables implies a perennially quantum Universe should Λ be zero (or, indeed, fixed at any value). Likewise, the smallness of Λ puts an upper bound on its uncertainty, and thus a lower bound on the unimodular clock’s uncertainty or the cosmic time for the emergence of classicality. Far from being the Planck scale, classicality arises at around 7×1011  GeV for the observed Λ, and taking the region of classicality to be our Hubble volume. We confirm this argument with a direct evaluation of the wave function of the Universe in the connection representation for unimodular theory. Our argument is robust, with the only leeway being in the comoving volume of our cosmological classical patch, which should be bigger than that of the observed last scattering surface. Should it be taken to be the whole of a closed Universe, then the constraint depends weakly on Ωk: for −Ωk<10−3, classicality is reached at >4×1012  GeV. If it is infinite, then this energy scale is infinite, and the Universe is always classical within the minisuperspace approximation. It is a remarkable coincidence that the only way to render the Universe classical just below the Planck scale is to define the size of the classical patch as the scale of nonlinearity for a red spectrum with the observed spectral index ns=0.967(4) (about 1011 times the size of the current Hubble volume). In the context of holographic cosmology, we may interpret this size as the scale of confinement in the dual 3D quantum field theory, which may be probed (directly or indirectly) with future cosmological surveys.
  • Journal article
    de Rham C, Engelbrecht L, Heisenberg L, Luescher Aet al., 2022,

    Positivity bounds in vector theories

    , The Journal of High Energy Physics, Vol: 86, Pages: 1-40, ISSN: 1029-8479

    Assuming unitarity, locality, causality, and Lorentz invariance of the, otherwise unknown, UV completion, we derive a new set of constraints on the effective field theory coefficients for the most general, ghost-free Generalized Proca and Proca Nuevo massive vector models. For the Generalized Proca model, we include new interactions that had not been previously considered in the context of positivity bounds and find these additional terms lead to a widened parameter space for the previously considered interactions. Although, the Generalized Proca and Proca Nuevo models are inequivalent, we find interesting analogues between the coefficients parameterizing the two models and the roles they play in the positivity bounds.

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