We discuss application of Wigner–Weyl formalism to the lattice models of condensed matter physics and relativistic quantum field theory. For the noninteracting models our technique relates Wigner transformation of the fermionic Green’s function with the Weyl symbol QW of lattice Dirac operator. We take as an example of the model defined on rectangular lattice the model of Wilson fermions. It represents

One of the alternative theories to Einstein’s general theory, a divergence-free theory was proposed by J. Nash with Lagrangian density given by 2RμνRμν−R2. Although it was proved that the Nash theory does not have classical Einstein limits, it has been proven to be formally divergent free and considered to be of interest in constructing theories of quantum gravity. The original Nash gravity without

We establish topological nature of Hall conductivity of graphene and other ℤ2 crystals in 2D and 3D in the presence of inhomogeneous perturbations. To this end the lattice Weyl–Wigner formalism is employed. The nonuniform mechanical stress is considered, along with the spatially varying magnetic field. The relation of the obtained topological invariant to level counting is clarified.

We give a brief overview of the kinetic theory for spin-1/2 fermions in Wigner function formalism. The chiral and spin kinetic equations can be derived from equations for Wigner functions. A general Wigner function has 16 components which satisfy 32 coupled equations. For massless fermions, the number of independent equations can be significantly reduced due to the decoupling of left-handed and right-handed

We evaluate the quantum expectation values in nonsimply connected spaces by using UV improved Green’s functions proposed by Padmanabhan, Abel, and Siegel. It is found that the results from these three types of Green’s functions behave similarly under changes of scales, but have minute differences. Prospects in further applications are briefly discussed.

In a primordial universe pre- (post-)inflationary era, there could be phases of early universe made of cold gas baryons, radiation and early post-inflationary cosmological constant. I showed that in the baryonic epoch, the quantum vacuum is unique. By using the standard quantization scheme for a massive minimally coupled scalar field with maximal conformal symmetry in the classical space–time, I demonstrated

We solve the equations of motion of a complex ϕ4 theory coupled to some given gauge field background. The solutions are given in both cylindrical and spherical coordinates and have finite energy.

This paper investigates the dynamics of spherical collapse in the framework of energy–momentum squared gravity. This theory overcomes the big-bang singularity and provides viable cosmological consequences in the early time universe. We proceed our work by considering the nonstatic spherically symmetric space–time in the interior and static spherically symmetric metric in the exterior regions of the

In quantum gravity theories, when the scattering energy is comparable to the Planck energy, the usual Heisenberg uncertainty principle breaks down and is replaced by generalized uncertainty principle (GUP). In this paper, the Dirac equation is studied for a single particle with spin and pseudospin symmetry in the presence of GUP, in 3+1 dimensions. For arbitrary wave l≠0, the Dirac equation with multiparameter

We investigate the contributions of the Cartan generators in the static potentials for various representations in the framework of the domain model of center vortices for SU(3) gauge theory. Using the center domains with the cores corresponding to only one Cartan generator H8, already given as a particular proposal, leads to some concavities in the potentials for higher representations. Furthermore

Landau gauge longitudinal and transverse gluon propagators are studied in lattice QCD with gauge group SU(2) at varying temperature and quark density. In particular, it is found that the longitudinal propagator decreases with increasing quark chemical potential at all temperatures under study, whereas the transverse propagator increases with increasing quark chemical potential at T<200 MeV and does

We review results of recent studies of transitions between bottomonium states obtained from analysis of the large e+e− data sample recorded by the Belle detector at various Υ-resonances and energy scan data in the center-of-mass energy range from s=10.63 GeV to 11.02 GeV.

We discuss the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Imposing an R-symmetry allows to satisfy easily the slow-roll conditions, avoiding the so-called η-problem, and leads to an interesting class of small field inflation models, characterized by an inflationary plateau around the maximum of

The Cryogenic Underground Observatory for Rare Events (CUORE) is a tonne-scale cryogenic experiment located at the Laboratori Nazionali del Gran Sasso that exploits bolometric technique to search for neutrinoless double beta decay (0νββ) of 130Te. The detector consists of a segmented array of 988 natural TeO2 cubic crystals arranged in a cylindrical compact structure of 19 towers. The detector construction

The NA48/2 experiment at CERN reports the first observation of the K±→π±π0e+e− decay from an exposure of 1.7×1011 charged kaon decays recorded in 2003–2004. A sample of 4919 candidates with 4.9% background contamination allows the determination of the branching ratio in the full kinematic region. The study of the kinematic space shows evidence for a structure-dependent contribution in agreement with

The first DAMA/LIBRA–phase2 model-independent results (exposure: 1.13ton×yr, and software energy threshold at 1 keV). They further confirm — with high confidence level — the evidence already observed by DAMA/NaI and DAMA/LIBRA–phase1 on the basis of the exploited model-independent dark matter (DM) annual modulation signature. The total exposure of the three experiments above the 2 keV software energy

The DArk Matter Particle Explorer (DAMPE) is a high-performance space particle detector launched in orbit in 2015 by a collaboration of Chinese, Italian and Swiss scientific institutions, coordinated by the Chinese Academy of Sciences. It consists of a high-resolution segmented BGO electromagnetic calorimeter with a depth of 32 radiation lengths, a silicon-tungsten tracker-converter with an angular

The framework of nonrelativistic effective field theory (NREFT) aims to generalize the standard analysis of direct detection experiments in terms of spin-dependent (SD) and spin-independent (SI) interactions. Here we performed EFT analysis and obtained sensitivity curves for liquid argon detectors to scattering of dark matter (DM) particles in case of different interaction models. DM velocity distribution

The cosmological history of the universe in the R+R2 gravity is studied starting from the “very beginning” up to the present time. The primordial inflationary expansion of the universe is considered and it is shown that the gravitational particle production by the oscillating curvature, R(t), led to a consistent transition to the Friedmann cosmology, but the cosmological evolution in the early universe

Gravitational equations of motion in modified theories of gravity have oscillating solutions, both in the early and in the present day universe. Particle production by such oscillations is analyzed and possible observational consequences are considered. This phenomenon has impact on energy spectrum of cosmic rays and abundance of dark matter particles.

Among particle theory candidates for the dark matter constituents. Axions and WIMPs are the most popular. In this paper, we discuss these then focus on our preferred astrophysical candidate, the Primordial Intermediate Mass Black Holes in the acronym DM=PIMBHs. The earliest experimental confirmation may come from microlensing of the Magellanic Clouds at the LSST 8 m telescope in the mid-2020s, or possibly

We point out the peculiar form of the gravitational wave signal expected from a gas of particles carry spin-3/2 produced during preheating. Given the very few ways that gravitinos can manifest themselves in an experimentally observable way, we stress the importance of improving the sensitivity of ultrahigh frequency detectors in the future. This review is based on work that appeared in Ref. 1.

While the QCD Lagrangian as the whole is only chirally symmetric, its electric part has larger chiral-spin SU(2)CS and SU(2NF) symmetries. This allows separation of the electric and magnetic interactions in a given reference frame. Artificial truncation of the near-zero modes of the Dirac operator results in the emergence of the SU(2)CS and SU(2NF) symmetries in hadron spectrum. This implies that while

The Standard Model predicts several rare Higgs boson decays, which have not yet been observed, but that could be enhanced in theories beyond the Standard Model. Among these are decays to light leptons, e.g. H→μμ. In addition, theories beyond the Standard Model may predict lepton-flavor violating decays of the Higgs boson. Results for these searches based on LHC pp collision data recorded at 13 TeV

The scattering of electroweak bosons tests the gauge structure of the Standard Model and is sensitive to anomalous quartic gauge couplings. In this paper, we present recent results on vector-boson scattering from the ATLAS experiment using proton–proton collisions with a center-of-mass energy of 13 TeV at the LHC. This includes the observation of ZZ, WZ, and same-sign WW production via vector-boson

The associated production a vector boson with J/ψ is a key observable for understanding of the quarkonium production mechanisms, including the separation of single and double parton scattering components. Measurements from the ATLAS detector at LHC on quarkonium production, including associated production of a W±+J/ψ and Z+J/ψ are presented. A study of the hidden-charm states X(3872) is also provided

Final states containing both leptons and jets can be used to probe for physics beyond the Standard Model. Searches for new physics models with these signatures, such as heavy neutrinos or leptoquarks, for example, are performed using the ATLAS experiment at the LHC. The results of the most recent searches on 13 TeV pp data will be presented.

Many theories beyond the Standard Model predict new phenomena accessible by the Lhc. Searches for new physics are performed using the Atlas experiment at the Lhc focusing on exotic signatures that are predicted in several theories, excluding supersymmetry. The results of recent searches using 13 TeV data, with the exception of those for Dark Matter signatures, and their interplay and interpretation

A measurement of Bs decay parameters using data collected by the ATLAS detector in pp collisions at 13 TeV in 2015–2017 is performed. Integrated luminosity of this sample is 80.5 fb−1. The measurement of physical parameters are statistically combined with results obtained from Run 1 data at 7 and 8 TeV. The measured value of CP-violating phase ϕs=−0.076±0.034(stat.)±0.019(syst.) is obtained, which

Electron and photon triggers are an important part of many physics analyses at the ATLAS experiment, where electron and photon final states are considered. Understanding the performance of electron and photon triggers at the High Level trigger as well as the Level-1 trigger was crucial to improve and adapt the trigger during changing run conditions of the Large Hadron Collider in Run 2 (2015–2018)

During Run 2 (2015–2018) the Large Hadron Collider has provided, at the World’s highest energy frontier, proton–proton collisions to the ATLAS experiment with high instantaneous luminosity (up to 2.1×1034cm−2s−1), placing stringent operational and physics requirements on the ATLAS trigger system in order to reduce the 40 MHz collision rate to a manageable event storage rate of 1 kHz, while not rejecting

The upcoming luminosity upgrade of the LHC will impose new requirements for the detector installations. To perform under these conditions the Micromegas (MM) technology was selected to be adopted in the New Small Wheel (NSW) upgrade, dedicated to precision tracking. A large surface of the forward regions of the Muon Spectrometer will be equipped with 8 layers of MM modules forming a total active area

Recent results by the CMS experiment on Drell–Yan, W and multiboson events are presented, including in particular the measurement of the electroweak mixing angle, the differential distributions in Drell–Yan events, and the electroweak production of one and two vector bosons in association with two jets. No deviations from the Standard Model predictions are found and stringent bounds are set on anomalous

The CMS Electromagnetic Calorimeter (ECAL), is a high granularity lead tungstate (PbWO4) crystal calorimeter operating at the CERN LHC. The ECAL performance has been crucial in the discovery and subsequent characterization of the Higgs boson. The original ECAL design considerations, and the improvements to the energy reconstruction and energy calibration algorithms to cope with the LHC Run II are described

The Sudbury Neutrino Observatory (SNO), whose main purpose was to study the neutrinos produced in the Sun, demonstrated that neutrinos can change flavor and, thus, they are massive particles. SNO detected and recorded neutrino and cosmic ray interactions from 1999 to 2006 and several analyses have been completed in the past year using legacy data. We present the results of the most recent ones: the

SNO+ is a multi-purpose experiment whose main goal is to study the nature of the neutrino mass through the observation of neutrinoless double-beta decay. Detection of this rare process would indicate that neutrinos are elementary Majorana particles, proving that lepton number is not conserved. The SNO+ detector will operate in three distinct phases with different target materials: water, pure liquid

The results from two currently running long-baseline neutrino experiments T2K and NOνA are presented, along with physics program for the next generation experiments — Hyper-K and DUNE. I will focus on hints and prospects of the discovery of CP violation in the leptonic sector.

We present new results of the DANSS experiment on the searches for sterile neutrinos. They are based on more than 2 million of inverse beta decay events collected at 10.7 m, 11.7 m and 12.7 m from the reactor core of the 3.1 GW Kalinin Nuclear Power Plant in Russia. This data sample is 2.4 times larger than the data sample in the previous DANSS publication. The search for the sterile neutrinos is performed

The knowledge of the initial flux, energy and flavor of current neutrino beams is the main limitation for a precise measurement of neutrino cross-sections. The ENUBET ERC project is studying a facility based on a narrow-band neutrino beam capable of constraining the neutrino fluxes normalization through the monitoring of the associated charged leptons in an instrumented decay tunnel. In ENUBET, the

The PANDA experiment at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt/Germany aims to investigate fundamental questions of hadron physics. PANDA is designed as a fixed-target experiment for an antiproton beam with a momentum range of 1.5 GeV/c to 15 GeV/c. In order to obtain an excellent particle identification of pions and kaons, two independent DIRC detectors have been developed

In this paper, we present two options of the toroid magnetic spectrometer dedicated to measure the energy and the polar and the azimuthal angles of the scattered from the ion’s nuclear electrons in the future electron-ion collider DERICA at JINR. These options differ by the opposite sign of the magnetic field. In one of the options, the toroid magnetic field bends electrons towards the collision line

We report on the design and the pilot phase of the μNet project that aims for the active involvement of Greek high school students in the experimental procedures of astroparticle physics and especially in cosmic ray physics. Through the anticipated educational program, the students from the geographical area of Peloponnese will construct and operate educational cosmic ray telescopes deployed at their

We compute the partition functions of 𝒩=1 gauge theories on S2×ℝ𝜀2 using supersymmetric localization. The path integral reduces to a sum over vortices at the poles of S2 and at the origin of ℝ𝜀2. The exact partition functions allow us to test Seiberg duality beyond the supersymmetric index. We propose the 𝒩=1 partition functions on the Ω-background, and show that the Nekrasov partition functions

The Belle II experiment is designed to collect 50 times more data than its predecessor. For a smooth collection of high-quality data, a robust and automated data transport and processing pipeline has been established. We describe the basic software components employed by the high level trigger. It performs a reconstruction of all events using the same algorithms as offline, classifies the events according

Classification of processes in heavy-ion collisions in the CBM experiment (FAIR/GSI, Darmstadt) using neural networks is investigated. Fully-connected neural networks and a deep convolutional neural network are built to identify quark–gluon plasma simulated within the Parton-Hadron-String Dynamics (PHSD) microscopic off-shell transport approach for central Au+Au collision at a fixed energy. The convolutional

In high energy particle colliders, detectors record millions of points of data during collision events. Therefore, good data analysis depends on distinguishing collisions which produce particles of interest (signal) from those producing other particles (background). Machine learning algorithms in the current times have become popular and useful as the method of choice for such large scale data analysis

Over the last decade, machine learning algorithms have become standard analysis tools in astroparticle physics, used by a variety of instruments and for an even larger variety of analyses. While a few characteristic patterns can be observed, the portability of established machine learning-based analysis chains from one experiment to another, remains challenging, as instrument-specific prerequisites

Neutrino experiments study the least understood of the Standard Model particles by observing their direct interactions with matter or searching for ultra-rare signals. The study of neutrinos typically requires overcoming large backgrounds, elusive signals, and small statistics. The introduction of state-of-the-art machine learning tools to solve analysis tasks has made major impacts to these challenges

On the way towards quantum gravity and the unification of interaction, several ideas have been rejected and avenues avoided because they were perceived as physically unviable. But in the literature there are works in which it was found the contrary, namely that those rejected topics make sense after all. Such topics, reviewed in this paper, are negative energies occurring in higher derivative theories

Lattice measurements provide adequate information to fix the parameters of long-distance effective field theories in Euclidean time. Using such a theory, we examine the analytic continuation of long-distance correlation functions of composite operators at finite temperature from Euclidean to Minkowski space–time. We show through an explicit computation that the analytic continuation of the pion correlation

The experiments at CERN’s Large Hadron Collider use the Worldwide LHC Computing Grid, the WLCG, for its distributed computing infrastructure. Through the distributed workload and data management systems, they provide seamless access to hundreds of grid, HPC and cloud based computing and storage resources that are distributed worldwide to thousands of physicists. LHC experiments annually process more

We present a simple method for analytic continuation of harmonic sums near negative and positive integer numbers. We provide a precomputed database for the exact expansion of harmonic sums over a small parameter near these integer numbers, along with MATHEMATICA code, which shows the application of the database for actual problems. We also provide the FORM code that was used to obtain the database

We consider the nonlinear classical field theory which results from adding to the Maxwell’s Lagrangian the contributions from the weak-field Euler–Heisenberg Lagrangian and a nonuniform part which involves derivatives of the electric and magnetic fields. We focus on the electrostatic case where the magnetic field is set to zero, and we derive the modified Gauss law, resulting in a higher-order differential

In the framework of finite-dimensional Fock space models, for a predefined fixed mean number of particles n̄k, it is shown that there is a “large” multidimensional subspace sn̄k of initial pure states, in the space S of all pure states, unitarily evolving to a subspace Sn̄k of final pure states which yield n̄k. As an example, in particular it follows that the blackbody form of the mean number of particles

A class of effective field theory called delta-theory, which improves ultraviolet divergences in quantum field theory, is considered. We focus on a scalar model with a quartic self-interaction term and construct the delta theory by applying the so-called delta prescription. We quantize the theory using field variables that diagonalize the Lagrangian, which include a standard scalar field and a ghost

We review the main recent progresses in noncommutative space–time phenomenology in underground experiments. A popular model of noncommutative space–time is 𝜃-Poincaré model, based on the Groenewold–Moyal plane algebra. This model predicts a violation of the spin-statistic theorem, in turn implying an energy and angular dependent violation of the Pauli exclusion principle. Pauli exclusion principle

Motivated by the recent interest in underground experiments phenomenology (see Refs. 1–3), we review the main aspects of one specific noncommutative space–time model, based on the Groenewold–Moyal plane algebra, the 𝜃-Poincaré space–time. In the 𝜃-Poincaré scenario, the Lorentz co-algebra is deformed introducing a noncommutativity of space–time coordinates. In such a theory, a new quantum field theory

Deep inelastic scattering is one of the best place to study hadron structures. In this paper we consider the target fragmentation region deep inelastic scattering process at leading twist. The calculations are carried out by applying the collinear expansion. In the collinear expansion formalism the multiple gluon scattering is taken into account and gauge links are obtained systematically and automatically

We review on further new developments of Generalized Uncertainty Principle (GUP) and implications for the cosmological vacuum energy. First, we introduce basic aspects of GUP as well as several possible different and viable formulation of it. Second, we move on discussing two recent new types of higher D-dimensional nonperturbative GUP models; which we dub D-Type-I and D-Type-II GUPs. The D-Type-I

The framework of the relativistic quantum mechanics on spatially flat FLRW space–times is considered for deriving the analytical solutions of the Dirac equation in different local charts of these manifolds. Systems of commuting conserved operators are used for determining the fundamental solutions as common eigenspinors giving thus physical meaning to the integration constants related to the eigenvalues