-
Mayo McFadden posted an update 6 months ago
Our results not only extend the higher-order band topology to massless and massive twisted moiré superlattice, but also demonstrate the importance of high-energy bands for fully understanding the nontrivial electronics.Stable nonsupersymmetric anti-de Sitter (AdS) vacua of string theory are widely believed not to exist. In this Letter, we analytically compute the full bosonic Kaluza-Klein spectrum around the G_2-invariant nonsupersymmetric AdS_4 solution of massive IIA supergravity and show that it is perturbatively stable. We also provide evidence that six other nonsupersymmetric AdS_4 solutions of massive IIA supergravity are perturbatively stable. Since previous studies have indicated that these AdS vacua may also be nonperturbatively stable, our findings pose a challenge to the swampland conjecture.Simulating quantum field theories is a flagship application of quantum computing. However, calculating experimentally relevant high energy scattering amplitudes entirely on a quantum computer is prohibitively difficult. It is well known that such high energy scattering processes can be factored into pieces that can be computed using well established perturbative techniques, and pieces which currently have to be simulated using classical Markov chain algorithms. These classical Markov chain simulation approaches work well to capture many of the salient features, but cannot capture all quantum effects. To exploit quantum resources in the most efficient way, we introduce a new paradigm for quantum algorithms in field theories. This approach uses quantum computers only for those parts of the problem which are not computable using existing techniques. In particular, we develop a polynomial time quantum final state shower that accurately models the effects of intermediate spin states similar to those present in high energy electroweak showers with a global evolution variable. The algorithm is explicitly demonstrated for a simplified quantum field theory on a quantum computer.We present a study on the phase stability of dense carbon dioxide (CO_2) at extreme pressure-temperature conditions, up to 6200 K within the pressure range 37±9 to 106±17 GPa. The investigations of high-pressure high-temperature in situ x-ray diffraction patterns recorded from laser-heated CO_2, as densified in diamond-anvil cells, consistently reproduced the exclusive formation of polymeric tetragonal CO_2-V at any condition achieved in repetitive laser-heating cycles. click here Using well-considered experimental arrangements, which prevent reactions with metal components of the pressure cells, annealing through laser heating was extended individually up to approximately 40 min per cycle in order to keep track of upcoming instabilities and changes with time. The results clearly exclude any decomposition of CO_2-V into the elements as previously suggested. Alterations of the Bragg peak distribution on Debye-Scherrer rings indicate grain coarsening at temperatures >4000 K, giving a glimpse of the possible extension of the stability of the polymeric solid phase.Starting from a fully quantized Hamiltonian for an ensemble of identical emitters coupled to the modes of an optical cavity, we determine analytically regimes of thermal, collective anti-bunching and laser emission that depend explicitly on the number of emitters. The lasing regime is reached for a number of emitters above a critical number-which depends on the light-matter coupling, detuning, and the dissipation rates-via a universal transition from thermal emission to collective anti-bunching to lasing as the pump increases. Cases where the second order intensity correlation fails to predict laser action are also presented.We perform a joint Bayesian inference of neutron-star mass and radius constraints based on GW170817, observations of quiescent low-mass x-ray binaries (QLMXBs), photospheric radius expansion x-ray bursting sources, and x-ray timing observations of J0030+0451. With this dataset, the form of the prior distribution still has an impact on the posterior mass-radius curves and equation of state (EOS), but this impact is smaller than recently obtained when considering QLMXBs alone. We analyze the consistency of the electromagnetic data by including an “intrinsic scattering” contribution to the uncertainties, and find only a slight broadening of the posteriors. This suggests that the gravitational-wave and electromagnetic observations of neutron-star structure are providing a consistent picture of the neutron-star mass-radius curve and the EOS.A first measurement of the longitudinal beam spin asymmetry A_LU in the semi-inclusive electroproduction of pairs of charged pions is reported. A_LU is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the A_LU^sinϕ_R moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics.WN_6 phase discovered at 126-165 GPa after heating of W in nitrogen. XRD refinements reveal a unit cell in space group R3m which is consistent with the WN_6 structure with armchairlike hexazine (N_6) rings, while strong A_1g Raman mode confirms its N─N single bonds. Density functional theory (DFT) calculations reveal balanced contributions of attractive interactions between W and covalent N_6 rings, and repulsions between N_6 rings that make WN_6 ultrastiff and tough. The WN_6 phase displays long bond lengths in the nearest N-N and pressure-enhanced electronic band gap, which pave the way for finding novel nitrides.We identify a class of dressed atom-photon states forming at the same energy of the atom at any coupling strength. As a hallmark, their photonic component is an eigenstate of the bare photonic bath with a vacancy in place of the atom. The picture accommodates waveguide-QED phenomena where atoms behave as perfect mirrors, connecting in particular dressed bound states (BSs) in the continuum with geometrically confined photonic modes. When applied to photonic lattices, the framework establishes a one-to-one correspondence between topologically robust dressed states and topologically robust photonic BSs seeded by a vacancy. This is used to predict new classes of dressed BSs in the photonic Creutz-ladder and Haldane models. In the latter case, states with nonzero local photon flux occur in which an atom is dressed by a photon orbiting around it.
Please follow & like us :)
All content contained on CatsWannaBeCats.Com, unless otherwise acknowledged,is the property of CatsWannaBeCats.Com and subject to copyright.