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Peñalver, D., De Vito, M., Balbinot, R., & Fabbri, A. (2026). Sonic black holes with thick horizons in BECs. Phys. Rev. D, 114(6), 065030–21pp.
Abstract: We consider simple one dimensional models of acoustic black holes formed by Bose-Einstein condensates where the flow is stepwise homogeneous. We concentrate on the case in which an extended sonic region is present, i.e., a region where the flow velocity equals exactly the speed of sound. These models can be thought of as acoustic black holes with a thick horizon. Particular attention is devoted to the number of created particles and to the density-density correlation functions, these latter being at present time the experimental tool to identify Hawking-like radiation in acoustic black holes.
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Usui, A., Niezgoda, A., & Gessner, M. (2026). Spinor Bose-Einstein condensate as an analog simulator of molecular bending vibrations. Quantum, 10, 2226–19pp.
Abstract: We demonstrate that spinor Bose-Einstein condensates (BECs) can be operated as an analog simulator of the twodimensional vibron model. This algebraic model describes bending vibrations of molecules and, in the case of triatomic molecules, exhibits two phases where linear and bent configurations are stabilised. Spinor BECs can be engineered to simulate states that correspond to linear or bent triatomic molecules, with the Wigner function of the BEC encoding information about the molecular configuration. We show how quantum simulations of the bending dynamics of linear molecules can be realised, and how preparing a linear configuration in the bent phase leads to a dynamical instability. In the dynamics triggered by the corresponding instability, a significant amount of entanglement is generated, and we characterise the dynamics with the squeezing parameter and the quantum Fisher information (QFI). The scaling of the non-Gaussian sensitivity, described by the difference between squeezing and QFI, grows with the system size once the spinor system crosses from the linear to the bent phase, thus serving as a dynamical witness for the quantum phase transition.
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ATLAS Collaboration(Aad, G. et al), Ahuja, S., Aikot, A., Cabrera Urban, S., Cantero, J., Carrion Martinez, C., et al. (2026). Search for displaced decays of long-lived particles in events with missing transverse momentum in √s=13 TeV pp collisions with the ATLAS detector. J. High Energy Phys., 08(8), 016–62pp.
Abstract: A search for long-lived particles in events with significant missing transverse momentum and at least one displaced vertex is presented. This analysis is performed using 137 fb(-1) of pp collision data collected between 2016-2018 during Run 2 of the Large Hadron Collider by the ATLAS detector. Displaced vertices are identified using two different secondary vertexing algorithms, including a novel “fuzzy” vertexing algorithm optimized for identifying displaced decays of heavy quarks. Separate searches are performed using each algorithm, and the expected Standard Model background is independently estimated for each search using a data-driven procedure. No significant excess is observed over the background in either case. The results are used to set 95% confidence-level limits on potential beyond-the-Standard Model physics that could produce this final state. Results are interpreted in the context of four models: long-lived gluinos that form R-hadrons before decaying, neutralinos decaying via Higgs-mediated channels in the Bino-Wino coannihilation model, long-lived Higgsinos decaying to axinos, and an exotic Higgs portal model predicting displaced decays of light pseudoscalars.
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Bustamante, M., Liu, Q. R., & Barenboim, G. (2026). Measuring neutrino mixing above 1 TeV with astrophysical neutrinos. Phys. Rev. D, 114(8), 083005–17pp.
Abstract: Neutrino mixing parameters are measured exclusively below 1 TeV. We show, for the first time, how to translate the flavor composition of TeV-PeV astrophysical neutrinos into direct constraints on the standard mixing parameters, placing the high-energy regime on the same quantitative footing as sub-TeV global fits. Present 11.4-year IceCube Medium-Energy Starting Events data leave these parameters unconstrained, limited by flavor-measurement uncertainties, and an irreducible degeneracy between theta 12 and the unknown astrophysical neutrino production mechanism. However, upcoming multitelescope observations will resolve theta 23 and theta 13 with 17%-50% precision. While coarser than terrestrial precision, this marks the transition of TeV-PeV neutrinos from a qualitative consistency check to a genuine measurement of three-flavor mixing. Finally, we establish concrete benchmarks for detecting beyond-Standard-Model effects, providing a roadmap to probe new physics that grows with energy and remains invisible to terrestrial neutrino experiments.
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Zhang, S. B., Yang, W. Q., Pan, S., Mena, O., Di Valentino, E., & Chakraborty, S. (2026). Late-time emergence of dark energy and its interaction with dark matter. Phys. Rev. D, 114(8), 083503–16pp.
Abstract: We present an interacting scenario between dark energy (DE) and dark matter (DM), where DE has an emergent nature, that means, DE was absent in the early Universe but it becomes effective only at late times. We consider two specific emergent DE models, one with no free parameters and the other featuring two parameters describing the speed and epoch of the transition. We constrain both scenarios using the cosmic microwave background (CMB) measurements from the Planck 2018 release, baryon acoustic oscillations from DESI DR2, and three different compilations of Type Ia supernovae (PantheonPlus, DESDovekie, and Union3). Our analysis indicates that current cosmological probes are not able to tightly constrain the speed of the transition. For both scenarios, the posterior distribution of the interaction parameter is shifted away from zero at more than 95% CL whenever the CMB data are combined with any of these additional probes, with the preferred direction corresponding to a transfer of energy from DE to DM. While CMB alone yields a high value of H0, in agreement with local determinations, this effect is reduced when DESI is added and disappears once supernova data are included. In contrast, the clustering parameter S8 is consistently shifted toward lower values in the combined datasets, and it is correlated with the preference for a negative interaction. However, according to the 4 chi 2 min and Bayesian evidence, none of the interacting models is favored over ACDM or w0waCDM, indicating that the interaction does not rescue these emergent DE models. Our results therefore highlight the limitations of these scenarios in addressing current cosmological tensions, while pointing to the crucial role of future data in further assessing their viability.
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