Papers

We prove that the $SL(2,\mathbb{C})$ character varieties of compact oriented surfaces and the generic relative $SL(2,\mathbb{C})$ character varieties of punctured surfaces admit divisorial log terminal (dlt) log Calabi-Yau compactifications. To do this, we establish a general result giving sufficient conditions for a compactification of an affine variety arising from a filtration of its algebra of regular functions to be log Calabi-Yau. We then apply this result to show that the compactifications constructed by Kutteri-Tehrani-Frohman in the compact case and by Tehrani-Frohman in the punctured case are log canonical and log Calabi-Yau.

The effects of black hole's spin in effective field theories (EFTs) of gravity are explored through observables of wave scattering on black hole backgrounds in the geometric optics approximation. The considered observables are polarisation rotation angle, wavenumber kick (or deflection angle), and (Shapiro/Wigner–Smith) time delay, each of which are related to gravitational Faraday rotation, gravitational spin Hall effect, and infrared causality. The observables are computed from scattering amplitudes through the Magnusian formalism, where the Magnusian is promoted to a matrix to account for helicity information. It is found that (1) the gravitational spin Hall effect in EFTs of gravity are qualitatively different from that of general relativity due to "noncommutative" wavenumber kicks, and (2) black hole's spin slightly enhances the causality constraints on EFT coefficients.

We initiate a study of centrally extended ($\textit{anomalous}$) symmetries in Kähler geometry, focusing on the simplest, and most ubiquitous, Abelian case. In particular, we provide a local description of the geometry admitting such isometries. A long-standing no-go theorem asserts that there is an obstruction to gauging such symmetries in the purely Kähler framework. Utilizing the language of sypersymmetry, we then show that these symmetries may be gauged within the setup of generalized Kähler geometry. Our results may be applied to quotients, T-dualities, etc.

We establish that supersymmetric monodromy defects in ABJM theory, also known as vortex loops, define integrable boundary states of the underlying alternating SU(4) spin chain. Exploiting the KT relation within the framework of the algebraic Bethe ansatz, we derive a closed-form expression for the leading-order one-point functions of non- protected operators in the presence of these defects. As a special case, our result reproduces the spin-chain overlap governing the three-point functions of two maximal giant gravitons and a single tiny graviton. We furthermore investigate the quantization of the theory in the defect background and compute the first quantum correction to the one-point functions in the simplest setting. Finally, we discuss possible extensions of our overlap formula.

In $(3+1)$ spacetime dimensions, we numerically calculate the suppression exponent of the false vacuum decay probability in the presence of a thermal bath and a black hole.

We investigate the geometrical and thermodynamical aspects of particle production in pp collisions over a broad center-of-mass energy, ranging from $\sqrt{s}=62.4$ GeV to 13 TeV using PYTHIA8. We study the azimuthal dependence of charged-particle production relative to the leading particle. This includes the study of the Tsallis–Pareto parameters extracted from the charged-particle transverse-momentum spectra in fixed $\Delta\phi$ intervals relative to the leading charged particle. The simultaneous analysis of charged-particle multiplicity and event topology demonstrates that the underlying event (UE) dominated region can be extended beyond the conventional transverse side region across RHIC and LHC energies. To further disentangle effects from soft and hard particle production mechanisms, the study is performed in different transverse spherocity and charged-particle flattenicity classes. We demonstrate that the UE region extends beyond the conventional transverse region, validating an enlarged angular interval of $40^\circ\lesssim|\Delta\phi|\lesssim140^\circ$ from RHIC to LHC energies. Event-shape selections reveal that jetty events consistently exhibit larger $q$ and lower $T_{\rm s}$ than isotropic events. The $\Delta\phi$ profiles of charged-particle multiplicity and transverse spherocity remain universal in shape across collision energies despite the strong increase in overall event activity, whereas the Tsallis parameters retain a residual, leading-particle-driven energy dependence in the near- and away-side regions.

We introduce a systematic framework for constructing spacetime and D-brane effective actions in bosonic string theory, encompassing both tachyon and massless modes. The actions are required to be gauge invariant and compatible with the expansion of sphere- and disk-level S-matrix elements. Our central proposal stipulates that, for each closed- or open-string channel, S-matrix poles involving an odd number of tachyons must be reproduced via an expansion in the effective action, whereas those with an even number of tachyons must be matched exactly. This criterion imposes strong selection rules: the bulk action contains only even powers of closed-string tachyon fields, and the D-brane action only even powers of open-string tachyon fields. In contrast, couplings of closed-string tachyons to D-branes are less constrained and allow both even and odd field multiplicities. As a concrete application, we analyze the disk-level amplitude involving two closed-string tachyons and demonstrate that the resulting linear and quadratic tachyon-D-brane interactions coincide precisely with those of type 0 theory. This is consistent with the duality between the orbifold of type 0 theory and the compactification of bosonic string theory on \(T^{16}\).

We discuss a mechanism for generating the baryon asymmetry in the early universe. We show that an axion-like particle can modify the related gauge field configurations in the Standard Model, thereby altering their dispersion relations. This change in the Chern-Simons number can source a violation of baryon number. We derive the relationship between the resulting baryon number and the evolution of the axion background. We estimate the baryon asymmetry produced via this mechanism and show that the observed value can be naturally achieved. We also show that axion photon coupling produces Cosmic Microwave Background spectral distortion. Our results show that the resulting distortion approaches a constant at low frequencies, unlike the conventional y-type and $\mu$-type distortions.

Ultra-heavy asymmetric dark matter (DM) particles captured by compact stars can thermalize, self-gravitate, and collapse to form an endoparasitic black hole (EBH), whose subsequent growth may transmute the host star into a black hole. The continued existence of old millisecond pulsars (MSPs) and white dwarfs (WDs) thus places powerful constraints on the DM particle mass $m_\chi$ and the DM-nucleon scattering cross-section $\sigma_{\rm n\chi}$. We derive an analytical expression for the transmutation timescale by solving the EBH growth equation, consistently accounting for Bondi accretion of stellar matter, Hawking evaporation, and sustained DM feeding of the EBH in a steady-state capture regime. We also incorporate quantum effects in baryonic accretion when the hydrodynamic description breaks down, providing a unified treatment of EBH growth across both particle and fluid regimes. Adopting a physically transparent collapse criterion for fermionic and bosonic asymmetric DM, we compute EBH transmutation timescales for representative MSPs and WDs in environments with different DM densities. Although the physical ingredients are broadly similar to previous studies, this work derives updated constraints through a closed-form analytical treatment of EBH growth and an adopted prescription for the EBH formation timescale, yielding a lower critical EBH mass for sustained growth and revised transmutation timescales. Requiring the transmutation time to exceed $\sim 1$ Gyr for MSPs and $\sim 10$ Gyr for WDs, we derive revised constraints on $\sigma_{\rm n\chi}$ over $m_\chi \sim 10^{6}$–$10^{14}$ GeV, and show that EBHs with initial masses as small as $\sim 4\times10^{4}$ kg can undergo sustained growth, extending the region of DM parameter space probed by compact stars.

We derive the gravitational radiation generated by a localised matter source in de Sitter spacetime at octupolar order in the multipolar expansion, working in generalised harmonic gauge in the future Poincaré patch. The scalar, vector, and tensor perturbation equations are solved explicitly, taking into account the cosmological tail. This constitutes the first extension of the de Sitter multipolar expansion beyond quadrupolar order. A key technical ingredient is a universal multipole moment differentiation identity, which unifies the relations between multipole moments into a single recursive formula and enables a controlled extension to higher multipoles. Using the symmetric trace-free tensor formalism of Blanchet, Damour, and Iyer, we further develop a systematic translation of the radiative solution into a spherical harmonic basis, and apply it to both the quadrupolar and octupolar metric perturbations. This representation renders the angular structure of the radiation manifest, simplifies the verification of the linearised field equations, and facilitates direct comparison with Bondi-gauge and other perturbative treatments of de Sitter spacetime.

We investigate how the sewing operations familiar from topological quantum field theory provide a useful organizational framework for semiclassical AdS/BCFT path integrals. Our purpose is not to identify AdS/BCFT with a topological field theory: the bulk geometry, the end-of-the-world brane, and the on-shell action remain intrinsically metric-dependent. Rather, we use the TQFT language of state preparation, orientation reversal, and gluing to separate interface data from local geometric contributions. For AdS$_3$/BCFT$_2$, we review how the Euclidean on-shell action and the Ryu–Takayanagi prescription reproduce the Affleck–Ludwig boundary entropy $\log g$ after holographic renormalization. We then formulate the Complexity=Action calculation in the presence of an end-of-the-world brane, carefully distinguishing bulk, brane, joint, and null-boundary contributions. We emphasize that finite terms in a relative Wheeler–DeWitt action depend on the choice of regulator matching and on the null-boundary counterterm scheme unless their scheme independence is established explicitly. Finally, we extend the geometric construction to a planar BTZ background and derive the brane embedding from the Neumann boundary condition. The resulting framework clarifies which aspects of holographic complexity are sensitive to boundary conditions and which require further renormalization input before they can be interpreted as universal boundary data.

We formulate a source-dependent QCD-to-BOEFT matching for the gluonic response of a stable compact heavy-quarkonium state. The matched complementary-space resolvent preserves coupled Born-Oppenheimer dynamics, while an exact Feshbach decomposition separates channels retained explicitly from sectors integrated out at the next matching step. Spectral separation, kernel analyticity, and joint propagation-source bounds provide sufficient conditions for a local channel-factorized OPE; otherwise low-energy BO poles and cuts remain dynamical. The weak-coupling pNRQCD response is recovered as a limiting reference problem. With the additional leading-$E1$, large-$N_c$/free-octet assumptions, the source-weighted spectral measure reproduces the established Bhanot-Peskin electric moments and dissociation cut. For a Coulombic spin-singlet $1S$ state we also obtain the sequential-$M1$ contribution $c_{B,GG}^{(1)ij} =5\pi\alpha_s^2(c_FV_{\rm iso}^{(s)})^2\delta^{ij}/16$ and the covariant-kinetic seagull contribution $c_{B,\mathrm{dia}}^{(1)ij} =-\pi\alpha_s^2\delta^{ij}/4$. These are identifiable components, not the complete magnetic matching coefficient.

We give the outlines of a proof for the existence of a mass gap for the 3d Yang-Mills theory in terms of an inequality on the eigenvalues of the Laplacian on the gauge-invariant configuration space.

Black-hole event horizons obey a set of evolution equations governing their intrinsic and extrinsic geometry. We study these equations in a two-timescale perturbative expansion about a Kerr background and derive strong constraints on the coarse-grained horizon dynamics. At leading order, the coarse-grained linear shear vanishes, while the horizon exhibits an adiabatic rigidity: the leading corrections to its angular velocity and inaffinity remain uniform on each horizon cut, while evolving on the slow timescale. We then provide a systematic procedure for transforming a perturbative bulk solution, given for example in Lorenz gauge, to an ingoing Newman–Unti gauge adapted to the horizon, allowing the perturbed horizon geometry to be extracted directly from the bulk metric. Finally, we formulate black-hole conservation laws associated with horizon symmetries, including energy, dynamical entropy, and angular momentum. We expand the charges through second order and their fluxes through third order in perturbation theory, providing a framework for future applications to horizon absorption and backreaction in extreme mass-ratio inspirals.

We construct a toy model of an evaporating black hole using approximately local degrees of freedom acting on “overlapping" qubits in which a version of black hole complementarity arises naturally. The operators corresponding to the radiation and the interior are identified as two distinct representations of the same fundamental algebra, thereby preventing the exact factorization of the Hilbert space into interior and exterior and avoiding the conventional no-cloning violations. We show how this toy model captures several qualitative and quantitative features of black hole evaporation and how the ability to account for this “overlap" in the entropy calculation leads to the recovery of a Page curve.

The renormalization of operators built out of Wilson lines that meet at an angle (cusp) involve what is known as the cusp anomalous dimension, a universal object appearing in many processes in QCD due to the divergences from gluonic interactions. In this paper, we consider the vacuum expectation value of a pair of cusped Wilson lines separated in the transverse direction. This configuration can be related to a simple observable in heavy quark transverse momentum-dependent (TMD) fragmentation as well as the TMD soft function. We compute the expectation values of Wilson loops in $N=4$ super Yang-Mills theory at strong coupling via the AdS/CFT correspondence, an approach complementary to perturbative calculations of the cusp anomalous dimension. We first present a thorough analysis, directly in Minkowski signature, of the Nambu-Goto action and its saddle points for a Wilson line configuration with a single cusp. We find that there are two different classes of saddle points whose contributions dominate different regions of parameter space. We calculate the cusp anomalous dimension $\Gamma_{\rm cusp}[\Delta\eta, \Delta\theta]$ for the whole range of $\Delta\eta$ from this setup, focusing on the cases $\Delta \theta = 0$ and $\Delta \theta = \pi$, and compare it with previous results in literature. We then use the techniques we developed to compute the expectation value of the two-cusp Wilson loop with transverse separation, and determine the profile of the transverse coordinate on the extremal surface in the large rapidity limit. We discuss the possible generalizations of our setup and results to soft functions in other gauge theories with a holographic dual.

In the context of type IIB superstring compactification, we demonstrate the assisted fibre inflation proposal for a four-field model realized using the orientifold of a tetra-quadric Calabi-Yau (CY) threefold. This CY threefold has an underlying permutation symmetry $S_4$ and belongs to both the list of CY threefolds, namely the Kreuzer-Skarke (KS) database as well as the Complete Intersection Calabi-Yau (CICY) database. After fixing the overall volume modulus of the CY threefold using the framework of perturbative large volume scenario, there are three Kähler moduli which remain flat and assist in driving fibre inflation via sub-leading corrections. In a particular benchmark model, we show that the effective inflaton shift of around $5.7$ M$_p$, as needed for driving fibre inflation, can be successfully shared by three inflaton moduli which need to be individually shifted by nearly $2.2$ M$_p$ only ! The main motivation for the work is to show that the effective large field excursions of the inflaton field is possible without the need of pushing the individual volume moduli towards a large super-Planckian excursion or close to the boundary of the Kähler cone which may create various subsequent challenges for the effective field theory and supergravity approximations, especially in Swiss-Cheese based models of fibre inflation.

We study the recursion coefficients of orthogonal polynomials and their associated Krylov dynamics in random matrix models with high-degree and possibly asymmetric polynomial potentials. We develop a moment recursion method that, when combined with the recursive algorithm, provides an efficient construction of the recursion coefficients. We also obtain their large-$n$ asymptotic behavior for general asymmetric potentials; for $Nw_d=1$, the leading asymptotic form of $R_n$ reproduces Freud's conjecture. We apply this framework to an asymmetric quartic potential and to the double-scaled Sachdev-Ye-Kitaev (DSSYK) model. In both models, the recursion functions capture the overall qualitative behavior of the recursion coefficients, and the gradient catastrophes of the recursion functions are associated with “chaotic” transition regions in the recursion coefficients. For the quartic potential, such regions can occur in both $R_n$ and $S_n$, whereas the DSSYK model can exhibit multiple transition regions in $R_n$, with the recursion function remaining accurate in the smooth intervals between them. Finally, we compute the corresponding spread complexity and find that transition regions do not qualitatively modify its behavior, while a two branch structure produces early time oscillations followed by monotonic growth.

Well-founded models of nonlinear electrodynamics (NED) are typically characterized by an additional parameter associated with their deviation from linear electrodynamics. In addition to that, from a phenomenological point of view, one of the most intriguing results of NED theory is that photons follow null geodesics according to an effective geometry. In particular, for a two-parameter electromagnetic Lagrangian density, we might observe the vacuum birefringence phenomenon, i.e., photons can follow null geodesics according to two effective geometries. Over the past few decades, efforts have been made to better understand the role of effective light cones in NED theory, as well as to constrain the additional free parameters provided by the theory. We investigate the ModMax black hole (BH) geometry, which is a well-motivated NED-sourced BH based on a two-parameter Lagrangian density, via light and orbital mechanics, considering the Shapiro time, the Sagnac effect, the gravitational and kinematic shifts, and the orbital precession. We find that the corrections introduced by nonlinear electromagnetic fields can be significant. In particular, we show that the Shapiro time delay and the gravitational redshift are identical for both effective metrics, making these observables insensitive to the birefringent structure of ModMax electrodynamics. By contrast, the Sagnac effect and the kinematic shifts remain capable of distinguishing the two effective geometries. Moreover, the orbital mechanics investigation, considering the orbital periapsis precession of the S2 star around Sagittarius A$^{\star}$, provides an observational constraint on the coupling between the NED parameter and the charge-to-mass ratio of the ModMax BH. Generally speaking, we provide a step-by-step procedure for theoretically exploring signatures of NED fields and constraining the free parameters of NED-sourced BH models.

Using the gravitational duals, we perform a systematic study of two notions of complexity in a family of three-dimensional gauge theories with rich infrared structure. For thermofield double states, we employ the complexity=volume prescription, which relates computational complexity to the volume of the dual Einstein-Rosen bridge. For one particle states created by the insertion of a local operator on the vacuum, we study their spreading in Krylov space, encoded holographically by the radial momentum of bulk excitations. We investigate these two notions of complexity across the parameter space of the theories, focusing on the two limiting values of a tunable parameter. Near the limit where the theories flow close to an intermediate conformal fixed point, both notions reveal distinct manifestations of “walking” dynamics. Near the opposite limit, computational complexity is largely insensitive to the confining nature of the ground state, whereas the frequency of oscillations in the Krylov spread complexity – set by the emerging infrared scale – is sensitive to the presence of confinement.

The boundary quantity that captures the growth of black-hole interiors quantified by holographic complexity remains unknown beyond 2d dilaton gravity. We provide a critical analysis of a partition-function construction of Krylov spread complexity for thermofield-double states that provides a dimension-independent boundary reconstruction from semiclassical holographic partition functions, while developing the present dynamical and bulk construction for the BTZ saddle. In the double-scaled Sachdev-Ye-Kitaev model, where exact and semiclassical results can be compared, we show that the classical limit is reliable only when taken after the complexity has been reconstructed; taking this limit at the level of individual Lanczos coefficients discards essential information. Applying the construction to a large-central-charge two-dimensional conformal field theory above the Hawking-Page temperature dual to a Bañados-Teitelboim-Zanelli black hole, we find an intermediate departure from early-time quadratic growth followed by behavior compatible with a return toward asymptotically quadratic growth, rather than the linear late-time behavior of the volume and the standard finite-functional complexity = anything class. We then match this boundary behavior to a generalized complexity = anything bulk object built from an infinite series of extrinsic-curvature invariants. The construction provides a systematic route from black-hole thermodynamics to Krylov dynamics and can naturally be extended to higher-dimensional holographic black holes.

We investigate a class of Ricci-flat Kähler metrics on generalized conifolds constructed via gauged linear sigma models (GLSMs) with indefinite signature. By introducing shadow coordinates (superfields) entering the sigma model with negative signature kinetic term, we show that these GLSMs yield explicit Ricci-flat metrics on complex cones over products of projective spaces. We provide a general formula for the resulting Kähler potentials, along with detailed examples. Our results suggest new directions for the study of Calabi-Yau metrics and toric geometry, and raise interesting questions about the geometric meaning of indefinite signature models. We also give an interpretation in terms of a novel generalized Kähler gauging.

Working to second order in cosmological perturbation theory, we reconsider the Large Scale White Noise (LSWN) effect proposed in [2511.13866] and [2511.15803]. We demonstrate that the kurvature density variable $\Delta \rho$ does indeed develop LSWN at second order. However, contrary to the claims of [2511.15803], we show that this is not inherited as an infrared (IR) pole in the second-order comoving curvature perturbation $R_2$. This apparent enhancement was an artifact of using a linear Poisson equation to relate two genuinely second order quantities. Further, we show that $R_2$ is protected from developing any such IR enhancement: $\lim_{k \rightarrow 0} \left( k^2 R_2 \right) = 0$, which follows from a conservation law in the soft limit. The constraint proposed in [2511.15803] and its implications for the small-scale primordial power spectrum are therefore invalid.

We prove existence and non-existence results for $L^2$ eigenforms for the Hodge Laplacian on complete non-compact Ricci flat manifolds with special holonomy, with a particular focus on gravitational instantons. We briefly describe the physical interpretation of these results in superstring and M-theory.

One-loop divergences in classically conformal theory in curved spacetime is a nontrivial issue if the theory under consideration possesses gauge invariance. In this case, quantization involves introducing the gauge-fixing term and the action of ghosts, both of which are not conformal. The formal proof of the conformal invariant renormalizability in this situation, including interacting theories, has been given in the paper from 1984 by one of the present authors. Owing to BRST symmetry, the contributions of the gauge-fixing and ghost sectors to the conformal variation of the effective action cancel each other. This cancellation does not hold in the finite part of the one-loop and higher-loops effective action, that results in the anomaly. In this paper, we extend the early results on conformal matter fields in external gravitational field and apply them to conformal quantum gravity, including the case of conformal gravity coupled to other conformal matter fields. The gauge-fixing in the Weyl-squared gravity is more complicated, nevertheless, the proof of the one-loop conformal invariant renormalization using BRST symmetry is possible. As a preliminary to conformal quantum gravity, we also present a detailed general proof of conformal invariant one-loop divergences in the corresponding semiclassical theory.

Rotating near-horizon extreme solutions of quadratic gravity are analyzed combining power series expansions and numerical calculations. Restricting to geometries with symmetries of the near-horizon extreme Kerr black hole (i.e., with the $\mathrm{AdS_2}$-structure), spherical horizon topology, and equatorial reflection symmetry, we introduce conformal coordinates simplifying the field equations of Einstein–Weyl gravity, i.e., quadratic gravity with vanishing scalar curvature. Employing the Frobenius analysis, we classify all power series solutions expanded around the equator as well as the poles, and obtain the recurrence relations. With the help of numerical analysis, we study fine-tuning of the free parameter to satisfy the global constraints on regular near-horizon extreme geometries. Computations of the horizon area, horizon scalar curvature, and rotational scalar reveal strong horizon deformations in some Bachian branches. Moreover, the absence of regular Bachian near-horizon geometries above a finite horizon area suggests an upper bound on the size of the corresponding extremal rotating black holes.

We revisit the notion of “quantum information flow” introduced in Bob Coecke's early work and seek to give it an explicit string-diagrammatic formalization. Given a semantics preserving string-diagram rewriting sequence, we first distinguish apparent through-paths, which depend on the current graphical presentation, from genuine through paths, which can be compatibly inherited through successive rewrites to a terminal decoupled bare wire factor. We then formally define a “Coecke flow line” in terms of this compatible inheritance relation. In particular, we use the ZX calculus, i.e., the ZX string diagram rewriting system, to illustrate the resulting formalism. In the physical setting of quantum protocols, a Coecke flow can be interpreted as a constrained, quasi-local, line-like presentation of a target bare wire morphism factor within the protocol string diagram.

We derive closed-form expressions for the thermal threshold functions of the finite-temperature proper-time renormalisation group (PTRG): until now these have been evaluated numerically, Matsubara mode by Matsubara mode. For the standard one-parameter regulator family, Poisson resummation of the Matsubara sum yields a rapidly convergent winding-number series of modified Bessel functions, and a single algebraic identity reduces every higher threshold function to this same closed form at a shifted kernel parameter. The sharp proper-time regulator, recovered as the exact $m\to\infty$ endpoint of the family with a controlled $O(1/m)$ approach, factorises into a field-dependent and a purely thermal piece. Built on them, the local potential approximation (LPA) and its refinement to a running anomalous dimension (LPA$'$) for the $O(N)$-symmetric theory reduce to established results, all cross-checked against the exact Wetterich equation with the optimised regulator. Two findings go beyond reduction. First, the known zero-temperature anomalous-dimension construction is extended here to finite temperature. Second, because the closed form holds for any real regulator parameter, the refined truncation's fixed point can for the first time be tracked as a continuous function of the regulator, rather than at a handful of isolated points, and is found to vary smoothly and remain bounded, with no special or pathological point anywhere on the line.

When a black hole rings after a merger, it emits gravitational waves at characteristic frequencies known as quasinormal modes (QNMs). In the eikonal limit, these modes are governed by the unstable circular light orbits that form the photon ring. In this work, we demonstrate that the ringing of a black hole has a precise thermal interpretation. A probe string propagating in the near-ring geometry acquires an induced Rindler horizon on its worldsheet, with a temperature set by the Lyapunov exponent of the photon ring. Out of this structure, the black hole QNMs emerge as thermal excitations, so that the characteristic ringing of a black hole is the retarded response of a thermal system living on the photon ring. We explicitly derive the QNM spectrum from two complementary perspectives: microscopically, via unstable transverse worldsheet fluctuations, and macroscopically, through the pole structure of the causal response function of an open thermal quantum system.

We study the adiabaticity of the cosmological perturbations in the context of inflationary Einstein-Gauss-Bonnet theories. We focus on viable inflationary Einstein-Gauss-Bonnet theories which are compatible with the current Cosmic Microwave Background radiation experiments and also are compatible with the GW170817 observations. We derive the effects of the adiabaticity requirement on the Einstein-Gauss-Bonnet physical parameters and we show that the sound speed of the scalar perturbations and the propagation speed of the tensor perturbations are constrained. We consider two classes of inflationary viable and GW170817-compatible theories, and in the first class the adiabaticity is not violated during inflation, while in the second class the adiabaticity is violated only at the end of inflation. We discuss the effects of the adiabaticity violation in the second class of models. From our analysis, it seems that only one class of viable EGB inflationary theories, which is also compatible with the GW170817 event, is free from adiabaticity pathologies.