Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)
We propose an embedding of the symTFT construction in (finite cut-off) holography. The proposal passes several non-trivial consistency checks reproducing the expected symTFTs in various cases, including the recently discussed symTFT for the 1-form symmetry of 4d N=4\mathcal{N}=4 SYM. Moreover, we comment on the possibility of unifying the symTFT and the symTh descriptions via the democratic formulation of Supergravity, using the 4d N=4\mathcal{N}=4 SYM theory as an example.
The contrast between the as-yet unmeasurable energy-loss effects in proton-nucleus collisions and the striking magnitude of the so-called high-momentum flow coefficients challenges our understanding of jet quenching mechanisms in large nucleus-nucleus collisions when applied to smaller systems. Intermediate-sized, light ion collisions will offer key insight into the system-size dependence of the interplay between jet energy loss and jet flow effects. To make quantitative predictions, we extend a semi-analytic jet quenching framework by coupling it to state-of-the-art event-by-event hydrodynamics and, for the first time, incorporate pre-equilibrium energy loss via the hydrodynamic attractor. A Bayesian analysis shows that an early-time onset of energy loss is compatible with RHIC and LHC measurements of jet suppression and jet elliptic flow in large systems, as well as hadron suppression, with the exception of hadron elliptic flow. Using these constraints, we predict both hadron and jet quenching observables in oxygen-oxygen collisions, finding sizable energy loss that exceeds the no-quenching baseline.
Component separation is the process with which emission sources in astrophysical maps are generally extracted by taking multi-frequency information into account. It is crucial to develop more reliable methods for component separation for future CMB experiments. We aim to develop a new method based on fully convolutional neural networks called the Cosmic microwave background Extraction Neural Network (CENN) in order to extract the CMB signal in total intensity. The frequencies used are the Planck channels 143, 217 and 353 GHz. We validate the network at all sky, and at three latitude intervals: lat1=0^{\circ}
The measurement of the cross-correlation function is crucial to assess magnification bias in galaxy surveys. Previous works used mini-tile subsampling, but accurately determining the integral constraint (IC) correction for unbiased estimation is challenging due to various factors. We present a new methodology for estimating the cross-correlation function, utilizing full field area and reducing statistical uncertainty. Covariance matrices were estimated by dividing each field into at least five patches using a k-mean clustering algorithm. Robustness was assessed by comparing spectroscopic and photometric lens samples, yielding compatible results. Cross-correlation and auto-correlation analyses in the GAMA fields revealed a stronger signal in GAMA15, likely due to rare large-scale structure combinations. Our findings highlight the robustness of the new methodology and suggest sample-specific effects. Subsequent papers in this series will explore other aspects of magnification bias and address potential biases from the GAMA15 signal on cosmological parameter constraints.
Fetching techniques from Generalised Geometry and Exceptional Field Theory, we develop a new method to identify consistent subsectors of four-dimensional gauged maximal supergravities that possess a (locally) geometric embedding in type IIB or 11D supergravity. We show that a subsector that is invariant under a structure group GSE7(7)\textrm{G}_\textrm{S} \subset \textrm{E}_{7(7)} can define a consistent truncation, even when GS\textrm{G}_\textrm{S} is not part of the symmetry of the gauged maximal supergravity. As an illustration of the method, type IIB supergravity on S1×S5\textrm{S}^{1} \times \textrm{S}^{5} is shown to admit a consistent truncation to pure N=4\mathcal{N}=4, D=4D=4 gauged supergravity. Explicit uplift formulae are presented which provide a type IIB alternative to the M-theory embedding constructed by Cvetic, Lu and Pope 2525 years ago.
Polarized synchrotron emission from ultra-relativistic electrons spiraling the Galactic magnetic field has become one of the most relevant emissions in the Interstellar medium these last years due to the improvement in the quality of low-frequency observations. One of the recent experiments designed to explore this emission is the QUIJOTE experiment. We aim to study the spatial variations of the synchrotron emission in the QUIJOTE MFI data, by dividing the sky into physically separated regions. For such task, we firstly use a novel component separation method based on artificial neural networks to clean the synchrotron maps. After training the network with simulations, we fit both EEEE and BBBB spectra by assuming a power-law model. Then, we give estimations for the index αS\alpha_{S}, the amplitude, and the ratio between BB and EE amplitudes. When analyzing the real data, we found a clear spatial variation of the synchrotron properties along the sky at 11 GHz, obtaining a steeper index in the Galactic plane of αSEE=3.1±0.3\alpha_{S}^{EE} = -3.1 \pm 0.3 and αSBB=3.1±0.4\alpha_{S}^{BB} = -3.1 \pm 0.4 and a flatter one at high Galactic latitudes of αSEE=3.05±0.2\alpha_{S}^{EE} = -3.05 \pm 0.2 and αSB=2.98±0.27\alpha_{S}^{B} = -2.98 \pm 0.27. We found average values at all sky of αSEE=3.04±0.21\alpha_{S}^{EE} = -3.04 \pm 0.21 and αSBB=3.00±0.34\alpha_{S}^{BB} = -3.00 \pm 0.34. Furthermore, after obtaining an average value of ASEE=3.31±0.08A_{S}^{EE} = 3.31 \pm 0.08 μK2\mu K^{2} and ASBB=0.93±0.02A_{S}^{BB} = 0.93 \pm 0.02 μK2\mu K^{2}, we estimate a ratio between BB and EE amplitudes of ASBB/ASEE=0.28±0.08A_{S}^{BB}/A_{S}^{EE} = 0.28 \pm 0.08. Based on the results we conclude that, although neural networks seem to be valuable methods to apply on real ISM observations, combined analyses with Planck, WMAP and/or CBASS data are mandatory to reduce the contamination from QUIJOTE maps and then improve the accuracy of the estimations.
We study the phase diagram of a confining three-dimensional N=1\mathcal{N}=1 supersymmetric U(N)×U(N+M)\text{U}(N)\times\text{U}(N+M) theory with holographic dual corresponding to a known string theory solution. The theory possesses a global U(1)\text{U}(1) symmetry under which magnetic monopoles are charged. We introduce both temperature and an external magnetic field for monopoles and find that there are deconfinement phase transitions as any of the two is increased, supporting monopole condensation as the possible mechanism for confinement. We find that the transition as the magnetic field is increased is second order, providing the first example in holographic duals of a deconfinement transition which is not first order. We also uncover a rich structure in the phase diagram, with a triple point and a critical point where a line of first order transitions end.
Recovering the polarized cosmic microwave background (CMB) is essential for shedding light on the exponential expansion of the very early Universe, known as cosmic inflation. Achieving this goal requires not only improved instrumental sensitivity but also the development of robust and diverse data analysis techniques. In this work, we explore a novel component separation approach based on neural networks to reconstruct the Stokes QQ and UU polarization maps. To validate the method, we first test the network on realistic \textit{Planck} sky simulations, finding a mean absolute error of 0.1±0.3 μK20.1 \pm 0.3~\mu K^{2} for the EE-mode and 0.1±0.3 μK2-0.1 \pm 0.3~\mu K^{2} for the BB-mode. We then apply the trained network to public \textit{Planck} observations, with results consistent with those obtained using the Commander method. Based on these findings, we conclude that neural network-based methods show potential as component separation techniques in polarization CMB experiments. However, substantial improvements and more comprehensive analyses are necessary before these methods can provide reliable high-precision cosmological estimates.
We study the class of AdS3×CP3\text{AdS}_3\times \mathbb{CP}^3 solutions to massive Type IIA supergravity with osp(62)\mathfrak{osp}(6|2) superconformal algebra recently constructed in arXiv:2304.12207 [hep-th]. These solutions are foliations over an interval preserving N=(0,6)\mathcal{N}=(0,6) supersymmetry in two dimensions, that in the massless limit can be mapped to the AdS4×CP3\text{AdS}_4\times \mathbb{CP}^3 solution of ABJM/ABJ. We show that in the massive case extra NS5-D8 branes, that we interpret as 12\frac{1}{2}-BPS surface defect branes within the ABJ theory, backreact in the geometry and turn one of the 3d field theory directions onto an energy scale, generating a flow towards a 2d CFT. We construct explicit quiver field theories that we propose flow in the IR to the (0,6)(0,6) SCFTs dual to the solutions. Finally, we show that the AdS3\text{AdS}_3 solutions realise geometrically, in terms of large gauge transformations, an extension to the massive case of Seiberg duality in ABJ theories proposed in the literature.
This paper is a write-up of the ideas that were presented, developed and discussed at the fourth International Workshop on QCD Challenges from pp to AA, which took place in February 2023 in Padua, Italy. The goal of the workshop was to focus on some of the open questions in the field of high-energy heavy-ion physics and to stimulate the formulation of concrete suggestions for making progresses on both the experimental and theoretical sides. The paper gives a brief introduction to each topic and then summarizes the primary results.
We investigate the relation between the emergence of a dilaton in gapped (confining) field theories, and the presence of either complex fixed points or instabilities in the strongly coupled dynamics in two classes of bottom-up holographic models. We demonstrate that in one of the two classes there is a critical line of first-order phase transitions (at zero temperature) that terminates at a critical point. We calculate the mass spectrum of fluctuations of the associated regular gravity backgrounds, which we interpret as bound states in the dual field theories. In proximity to the second-order phase transition, we find a parametrically light scalar state, and its composition leads us to identify it as a dilaton.
We study the two families of AdS3×S3×S2×Σ2_3\times S^3\times S^2\times \Sigma_2 solutions to massive Type IIA supergravity with small and large (0,4)(0,4) supersymmetries constructed recently in the literature, in connection with the AdS7×S2×I_7\times S^2\times I solutions to massive Type IIA, to which they asymptote locally. Based on our analysis of various observables, that we study holographically, we propose an interpretation of the first class of solutions as dual to deconstructed 6d (1,0) CFTs dual to AdS7_7, and of the second class as dual to surface defects in the same 6d theories. Among the observables that we study are baryon vertices and giant graviton configurations in quiver-like constructions.
We study a class of UV-complete, strongly coupled, confining three-dimensional field theories, that exhibit a novel stabilisation mechanism for the mass of the lightest scalar composite state, relying on the existence of a critical point. The theories admit a holographic dual description in terms of regular backgrounds in eleven-dimensional supergravity. Their phase diagram includes a line of first-order phase transitions ending at the critical point, where the transition becomes of second order. We calculate the mass spectrum of bound states of the field theory, by considering fluctuations around the background solutions, and find that, near the critical point, a hierarchy of scales develops, such that one state becomes parametrically light. We identify this state as the dilaton, the pseudo-Nambu-Goldstone boson associated with the spontaneous breaking of approximate scale invariance. This stabilisation mechanism might be exploited to address hierarchy problems in particle and astroparticle physics.
We explicitly compute correlation functions with the insertion of a continuous symmetry defect in bosonic field theories. To recover the expected action, the definition of the defect must be modified to include a specific contact term. This can be regarded as a singular background gauge field for the global symmetry. It can be traced to the definition of the generating functional for current correlators, where the source is akin to a background gauge field for the symmetry. For holographic theories, it has been proposed that continuous symmetry defects are realized in terms of non-BPS D(q1)D(q-1) branes. We argue that these can be regarded as Dq/DqDq/\overline{Dq} system and show its application to the case of the baryonic symmetry in the Klebanov-Witten theory. The Dq/DqDq/\overline{Dq} can be regarded as a particular regularization of the defect, holographically realizing the field theory discussion.
Due to the progressive increase in size of the latest Cherenkov-type detectors, it is becoming increasingly important to design a suitable compensation system based on coils of the Earth's magnetic field to ensure the correct operation of the photomultipliers (PMTs). Until now, most studies have assessed the correct functioning of such a system by the proportion of PMTs experiencing more than 100 mG of magnetic field perpendicular to their axis. In the present study, we discuss whether this evaluation parameter is the most appropriate and propose the average residual perpendicular magnetic field as an alternative that more closely reflects the loss of detection efficiency of PMTs. A compensation system design is also proposed that offers good results as well as being economical to optimise this parameter.
We consider a previously constructed class of massive Type IIA AdS2×_2\timesS7×I^7\times I solutions with OSp(82)(8|2) symmetry, as well as OSp(62)(6|2)-symmetric ones, by replacing the S7^7 with the orbifold S7/Zk^7/\mathbb{Z}_k. In both cases we construct global solutions for which the interval II is bounded between physical singularities, by allowing D8-branes transverse to II. We also generate a new class of Type IIB AdS$_2\times \mathbb{CP}^3\times\text{S}^1\times I$ solutions by T-duality and establish a chain of dualities that maps the massless limit of these classes to AdS4/Zk×S7/Zk_4/\mathbb{Z}_{k'}\times\text{S}^7/\mathbb{Z}_k, thus identifying the brane configurations yielding these solutions. We propose that the N=8{\cal N}=8 solutions are dual to a theory living on a D0-F1-D8 brane intersection which has a description in terms of disconnected quivers and similarly for the ${\cal N}=6$ solutions.
We report on the classification of supersymmetric AdS2 solutions of Type II supergravity and the discovery of new solutions
We explore a new class of AdS3_3 solutions in massive type IIA supergravity preserving N=(0,6)\mathcal{N} = (0,6) supersymmetry and realising an osp(62)\mathfrak{osp}(6|2) superconformal algebra. These solutions exhibit an SO(6)-symmetric internal space constructed from a CP3\mathbb{CP}^3, and are fully specified by a single cubic function controlling the fluxes and warping. We propose a brane box configuration underlying the solutions from which we construct a two-dimensional quiver gauge theory whose anomaly structure and central charge we analyse, and from which we can realise Seiberg-like dualities as large gauge transformations. The brane box configuration suggests an interpretation of the solutions as dual to surface defects within the ABJ(M) theory. Our findings provide a concrete setting for exploring holography beyond the ABJM vacuum. Remarkably, no explicit field theories are currently known to realise N=(0,6)\mathcal{N} = (0,6) supersymmetry in two dimensions, making our setup a promising and largely unexplored direction for field-theoretic investigations.
We review recent progress in constructing type IIB AdS3_{3} flux vacua that exhibit parametrically-controlled scale separation and come along with integer-valued conformal dimensions for the would-be dual CFT2_{2} operators. We comment on the anisotropic nature of the associated internal spaces, as well as on the existence of polynomial shift symmetries underlying the mass spectra. We conclude by outlining open questions and potential directions for future research, partially inspired by the Swampland program.
The generalized Komar (d2)(d-2)-form charge can be modified by the addition of any other on-shell closed (conserved) (d2)(d-2)-form charge. We show that, with Kaluza--Klein boundary conditions, one has to add a charge related to the higher-form symmetry identified in Ref.~\cite{Gomez-Fayren:2024cpl} to the naive Komar charge of pure 5-dimensional gravity to obtain a conserved charge charge whose integral at spatial infinity gives the mass. The new term also contains the contribution of the Kaluza--Klein monopole charge leading to electric-magnetic duality invariance.
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