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Computational modeling of optical activity, circular dichroism (CD) and optical rotatory dispersion, is rapidly becoming a useful supplement to experimental studies of absolute configuration. Here, we investigate the predictions of two alternative formulations of the rotational strength based on time-dependent density functional theory (TD-DFT), for a series of high symmetry chiral systems. We employ the TD-DFT method as realized in Gaussian 03 suite with the hybrid functional B3LYP and as incorporated in the Amsterdam density functional (ADF) suite with PBE and SAOP functionals. The high-symmetry systems described here are somewhat larger than those used to evaluate the influence of basis sets and density functional choice, and for such large systems the very extensive basis sets recommended by most investigators may not be suitable for routine use. We observe that useful results for these systems can be obtained in modest bases, and in particular that diffuse functions may not be required for informative use of the ADF implementation. The statistical average of orbital potentials (SAOP) model developed by Baerends is essential to the success of the ADF implementation. In some cases chirality is defined by features of the molecular structure remote from the chromophore. This is a severe test of the TD-DFT theory, since high-lying excitations define the most prominent features of the CD spectra, and complicates the use of computations to guide the assignment of absolute configuration. Experimental investigation of the high symmetry systems described here is desirable. [ABSTRACT FROM AUTHOR]

Graphyne-based nanotubes are cylindrical structures made up of a single layer of graphyne that has been rolled into a tube. These one-dimensional structures are constructed from carbon atoms with both sp and sp2 hybridization. The common graphene-based carbon nanotubes, and graphyne-based nanotubes including α-, β-, γ-, α2-, 6,6,12-, and δ-graphyne nanotubes are introduced. The atomic structures and electronic characteristics of these tubes are reviewed. The electronic band structures and density of states calculated by density functional theory are presented. The nanotubes with different types and chiralities display either metallic or semiconducting characteristics. The variety of structures and electronic properties of these nanotubes make them extremely hopeful for applications, especially in nanoelectronic devices such as field emission transistors, sensors, nanoelectromechanical systems, super capacitors, energy and data storage devices. [ABSTRACT FROM AUTHOR]

A mechanism of the heavy quark dominance in the orbital excitation is proposed in this paper which is testified to be reasonable for singly and doubly heavy baryons. In the relativistic quark model, an analysis of the Hamiltonian figures out the mechanism that the excitation mode with lower energy levels is always associated with the heavy quark(s), and the splitting of the energy levels is suppressed by the heavy quark(s). So, the heavy quarks dominate the orbital excitation of singly and doubly heavy baryons. Furthermore, a physical understanding of this mechanism is given in a semi-classical way. Accordingly, the predicted mass spectra of singly and doubly heavy baryons confirm the rationality of this mechanism. In addition, an interesting consequence of this mechanism is that a heavy-light meson is more likely to be produced in the strong decay of the high-orbital excited states, which is supported by experiments. This mechanism is rooted in the breakdown of the mass symmetry. Therefore, it may be also valid for other multi-quark systems, such as the tetraquarks Qqqq and QQqq, or the pentaquarks Qqqqq and QQqqq. [ABSTRACT FROM AUTHOR]

We give a detailed (microscopic) description of the geometric and non-geometric fundamental branes and their bound states in Type II superstring compactifications preserving N = 6 supersymmetry. We consider general boundary states that couple to the twisted sector and compute the relevant annulus amplitudes. We check consistency of the construction by relating the ‘transverse’ channel, corresponding to closed-string ‘tree-level’ exchange, with the ‘direct’ open-string loop channel. Focussing on the Type IIA frame, we show that D0-D4 have the expected tension for a geometric brane, while the non-geometric D2-D6 boundary states have a tension equal to 1 / K the one of a geometric brane for the ZK orbifold. This is consistent with Fricke T-duality of the N = 6 model. [ABSTRACT FROM AUTHOR]

Developing chiral receptors with an endo-functionalized cavity for chiral recognition is of great significance in the field of molecular recognition. This study presents two pairs of chiral naphthotubes containing a bis-thiourea endo-functionalized cavity. Each chiral naphthotube has two homochiral centers which were fixed adjacent to the thiourea groups, causing the skeleton and thiourea groups to twist enantiomerically through chiral transfer. These chiral naphthotubes are highly effective at enantiomerically recognizing various neutral chiral molecules with an enantioselectivity up to 17.0. Furthermore, the mechanism of the chiral recognition has been revealed to be originated from differences in multiple non-covalent interactions. Various factors, such as the shape of cavities, substituents of guests, flexibility of host and binding modes are demonstrated to contribute to creating differences in the non-covalent interactions. Additionally, the driving force behind enantioselectivity is mainly attributed to enthalpic differences, and enthalpy -entropy compensation has also been observed to influence enantioselectivity. Chiral receptors with an endo-functionalized cavity for chiral recognition are of interest in the field of molecular recognition. Here, the authors develop chiral naphthotubes containing a bis-thiourea endo-functionalized cavity to effectively recognize neutral chiral molecules with high enantioselectivity. [ABSTRACT FROM AUTHOR]

Multi-particle states with additional pions are expected to result in a difficult-to-control excited-state contamination in lattice simulations. We show that heavy meson chiral perturbation theory can be employed to estimate the contamination due to two-particle B π states in various B-meson observables, like the B-meson decay constant and the B ∗ B π coupling. We work in the static limit and to next-to-leading order in the chiral expansion, i.e. including O (p). The B π states are found to typically lead to an overestimation of the observables at the few percent level. We determine two of the LECs from B → π form factor computations of the KEK group (Colquhoun et al. in Phys. Rev. D 106:054502, 2022) and discuss ways to determine the others. In particular, one LEC which is associated with smeared interpolating fields seems to be easily accessible and thus opens up a way to systematically study the effect of smearing on excited-state effects. [ABSTRACT FROM AUTHOR]

We propose confining dualities of N = (0, 2) half-BPS boundary conditions in 3d N = 2 supersymmetric SU(N), USp(2n) and SO(N) gauge theories. Some of these dualities have the novel feature that one (anti)fundamental chiral has Dirichlet boundary condition while the rest have Neumann boundary conditions. While some of the dualities can be extended to 3d bulk dualities, others should be understood intrinsically as 2d dualities as they seem to hold only at the boundary. The gauge theory Neumann half-indices are well-defined even for theories which contain monopole operators with non-positive scaling dimensions and they are given by Askey-Wilson type q-beta integrals. As a consequence of the confining dualities, new conjectural identities of such integrals are found. [ABSTRACT FROM AUTHOR]

We compute all worldsheet three-point functions involving spectrally-flowed operators in chiral multiplets of the space-time theory for strings in AdS3×S3×T4, thus completing the analysis of the full AdS3/CFT2 chiral ring. We make use of techniques recently developed for the bosonic sector, based on holomorphic covering maps from the worldsheet to the AdS3 boundary. We highlight the role of the so-called series identifications when dealing with the complications originated by picture-changing spectrally-flowed states. We find an exact agreement with the predictions from the holographic CFT at the symmetric orbifold point. [ABSTRACT FROM AUTHOR]

We revisit the modular weights in type IIB magnetized D-brane models. The simple analysis of wave function shows that the four-dimensional matter fields have the modular weight -1/2, but it may shift as one in type IIA intersecting D-brane models. For example, the localized gauge flux as well as the localized curvature can shift the modular weight in the magnetized D-brane models. Such corrections do not affect physical couplings such as physical Yukawa couplings. However, it leads to differences in supersymmetry breaking sfermion masses, which depend on the modular weights, although the A-term coefficients and the sum of sfermion masses squared seem to be the same between two models. [ABSTRACT FROM AUTHOR]

It is an important question in string compactification whether complex structure moduli stabilization inevitably ends up with a vacuum expectation value of the superpotential W of the order of the Planck scale cubed. Any thoughts on volume stabilization and inflation in string theory, as well as on phenomenology of supersymmetric Standard Models, will be affected by the answer to this question. In this work, we follow an idea for making W ≃ 0 where the internal manifold has a vacuum complex structure with arithmetic characterization, and address Calabi–Yau fourfold compactification of F-theory. The moduli space of K3 × K3 orbifolds contain infinitely many such vacua. Arithmetic conditions for a W = 0 flux are worked out, and then all the K3 moduli have supersymmetric mass. Possible gauge groups, matter representations and discrete symmetries are studied for the case of Z 2 -orbifolds. [ABSTRACT FROM AUTHOR]

Chiral magnetic insulators manifest novel phases of matter where the sense of rotation of the magnetization is associated with exotic transport phenomena. Effective control of such phases and their dynamical evolution points to the search and study of chiral fields like the Dzyaloshinskii–Moriya interaction. Here we combine experiments, numerics, and theory to study a zig-zag dipolar lattice as a model of an interface between magnetic in-plane layers with a perpendicular magnetization. The zig-zag lattice comprises two parallel sublattices of dipoles with perpendicular easy plane of rotation. The dipolar energy of the system is exactly separable into a sum of symmetric and antisymmetric long-range exchange interactions between dipoles, where the antisymmetric coupling generates a nonlocal Dzyaloshinskii–Moriya field which stabilizes winding textures with the form of chiral solitons. The Dzyaloshinskii–Moriya interaction acts as a vector potential or gauge field of the magnetic current and gives rise to emergent magnetic and electric fields that allow the manifestation of the magnetoelectric effect in the system. [ABSTRACT FROM AUTHOR]

The recently discovered kagome superconductors AV3Sb5 (A = K, Rb, Cs) exhibit unusual charge-density-wave (CDW) orders with time-reversal and rotational symmetry breaking. One of the most crucial unresolved issues is identifying the symmetry of the superconductivity that develops inside the CDW phase. Theory predicts a variety of unconventional superconducting symmetries with sign-changing and chiral order parameters. Experimentally, however, superconducting phase information in AV3Sb5 is still lacking. Here we report the impurity effects in CsV3Sb5 using electron irradiation as a phase-sensitive probe of superconductivity. Our magnetic penetration depth measurements reveal that with increasing impurities, an anisotropic fully-gapped state changes to an isotropic full-gap state without passing through a nodal state. Furthermore, transport measurements under pressure show that the double superconducting dome in the pressure-temperature phase diagram survives against sufficient impurities. These results support that CsV3Sb5 is a non-chiral, anisotropic s-wave superconductor with no sign change both at ambient and under pressure. In the kagome superconductor CsV3Sb5 the symmetry of the superconducting gap is still in question, both at ambient pressure and under high pressure. Here, via controlled introduction of impurities, the authors report evidence for a non-chiral full superconducting gap with no sign change. [ABSTRACT FROM AUTHOR]

Superconducting vortices are promising traps to confine non-Abelian Majorana quasi-particles. It has been widely believed that bulk-state topology, of either normal-state or superconducting ground-state wavefunctions, is crucial for enabling Majorana zero modes in solid-state systems. This common belief has shaped two major search directions for Majorana modes, in either intrinsic topological superconductors or trivially superconducting topological materials. Here we show that Majorana-carrying superconducting vortex is not exclusive to bulk-state topology, but can arise from topologically trivial quantum materials as well. We predict that the trivial bands in superconducting HgTe-class materials are responsible for inducing anomalous vortex topological physics that goes beyond any existing theoretical paradigms. A feasible scheme of strain-controlled Majorana engineering and experimental signatures for vortex Majorana modes are also discussed. Our work provides new guidelines for vortex-based Majorana search in general superconductors. It is widely believed that bulk-state topology is crucial for enabling Majorana zero modes in solid-state systems. Here, the authors predict that superconducting vortices containing Majorana zero modes can arise from topologically-trivial electronic bands, expanding the pool of materials which may host such phenomena. [ABSTRACT FROM AUTHOR]

Combining the quark model, the quark-pair-creation mechanism and B(*) K ¯ interaction, we have investigated the near-threshold P-wave Bs states in the framework of the Hamiltonian effective field theory. With the heavy quark flavor symmetry, all the parameters are determined in the Ds sector by fitting the lattice data. The masses of the bottom-strange partners of the D s 0 ∗ 2317 and D s 1 ∗ 2460 are predicted to be M B s 0 ∗ = 5730.2 − 1.5 + 2.4 MeV and M B s 1 ∗ = 5769.6 − 1.6 + 2.4 MeV, respectively, which are well consistent with the lattice QCD component. The two P-wave Bs states are the mixtures of the bare b ¯ s core and B(*) K ¯ component. Moreover, we find a crossing point between the energy levels with and without the interaction Hamiltonian in the finite volume spectrum in the 0+ case, which corresponds to a CDD (Castillejo-Dalitz-Dyson) zero in the T-matrix of the B K ¯ scattering. This CDD zero will help deepen the insights of the near-threshold states and can be examined by future lattice calculation. [ABSTRACT FROM AUTHOR]

Theoretical studies of the theory of nematic superconductivity in doped insulators of the Bi2Se3 family have been reviewed. It is experimentally shown that their transition to the superconducting state is accompanied by spontaneous rotational symmetry breaking. This superconductivity is called nematic superconductivity and is described well by a triplet vector order parameter. The main concepts of the microscopic theory and the Ginzburg–Landau theory for nematic superconductivity have been presented. The competition between possible superconducting order parameters in topological insulators has been discussed. It has been shown that hexagonal distortions of the Fermi surface are necessary for implementing the nematic phase. This phase is very sensitive to disorder because charged impurities reduce the critical temperature. The doping-induced transition from the closed to open Fermi surface affects the competition of superconducting phases. Surface Andreev states in nematic superconductors have been discussed. The phenomenological Ginzburg–Landau theory for the two-component order parameter is derived from the microscopic theory. Using the Ginzburg–Landau theory, it has been shown that the ground state is either the real nematic order parameter with the spontaneous deformation of the lattice or a complex chiral order parameter with spontaneous magnetization. The vector structure of the order parameter is responsible for an unconventional relation between superconductivity and the lattice deformation and magnetization. This leads to strong anisotropy of the second critical field, to the appearance of spin vortices (which can be carried by Kramers pairs of Majorana fermions), and to unconventional Pauli paramagnetism for triplet Cooper pairs. [ABSTRACT FROM AUTHOR]

We present some exact solutions to the ideal hydrodynamics of a relativistic superfluid with an almost-conformal equation of state. The solutions have stress tensors which are invariant under Lorentz boosts in one direction, and represent superfluid generalisations of the Bjorken and Gubser flows. We also study corrections to the flows in first-order hydrodynamics, arguing that dissipation is dominated by the shear viscosity. We present some simple numerical solutions for these viscous corrections. Finally, we estimate the size of corrections to the flows arising when the spontaneously broken U(1) symmetry responsible for superfluidity is only approximate, giving the corresponding Goldstone boson a small non-zero mass. We find that the massless solutions can still provide good approximations at sufficiently small spatial rapidities. [ABSTRACT FROM AUTHOR]

In this paper, a terahertz (THz) metamaterial (MM) is designed to achieve ultra-broadband, highly efficient polarization conversion and asymmetric transmission (AT) for linearly polarized (LP) wave. The MM structure is composed of two orthogonal metallic sub-wavelength grating layers and a sandwiched cross-shaped array layer, in which the orthogonal grating layers are used as polarization filters to enhance AT parameters and the cross-shaped structure functions as the polarization converter. Owing to the coupling between two different cut-wires (CWs) and the excitation of higher-order plasmon mode in the cross-shaped structure, the polarization conversion bandwidth is greatly expanded. Results show that the polarization conversion rate (PCR) of the proposed MM structure can exceed 0.99 from 0.41 to 2.38 THz. The AT parameters are above 0.64 in the range of 0.50–2.41 THz with a relative bandwidth of 131.27%, and the near-perfect AT effect with AT parameter in excess of 0.8 occurs at two bands, from 0.53 to 1.48 THz and from 1.80 to 2.06 THz, with the relative bandwidth of 94.53% and 13.47%, respectively. Comparisons of our results with other published works prove that our proposed MM can provide relatively wider bandwidth and higher AT parameter. Due to the excellent performance, the proposed MM has potential applications in designing THz diodes. [ABSTRACT FROM AUTHOR]

Utilizing molecular dynamics (MD) simulation, the effects of grain size and twin boundary spacings (TBS) on the deformation mechanisms of nano-twinned (NT) Ag-doped Cu alloys are investigated. The doped Ag atoms are segregated to grain boundary affect zone (GBAZ). Both lattice and twining partial dislocations emitted from the amorphous inter-granular layer (GBAZ-segregated domains) are frequently observed, which switch on the strength enhancement and strength softening regime respectively. Consequently, it is hard to relate flow stress with dislocation density. Fortunately, the average flow stress of NT Ag-doped Cu alloy seems to be sensitive to GBAZ phase transition rather than dislocation density. [ABSTRACT FROM AUTHOR]

Low energy constants (LECs) of heavy-hadron chiral perturbation theory (HH χ PT) for low lying bottom mesons are computed. The available data for J P = 0 - , 1 - , 0 + and 1 + of bottom mesons are used to analyze the mass formulae of low lying bottom mesons having low energy constants up to one-loop corrections. The decay widths of bottom mesons ( J P = 0 + and 1 + ) are analyzed to constraint the couplings. These coupling constants are used to fix the one-loop corrections in the mass formulae. The masses and couplings are then used to find LECs from mass formulae. The behavior of tree level masses are studied by changing LECs. This study has improved over the infinite number of sets of LECs for low lying bottom meson masses in HH χ PT. [ABSTRACT FROM AUTHOR]

Extensions of the minimal supersymmetric standard model (MSSM) gauge group abound in the literature. Several of these include an additional U(1)X gauge group. Chiral fermions' charge assignments under U(1)X are constrained to cancel local anomalies in the extension and they determine the structure and phenomenology of it. We provide all anomaly-free charge assignments up to a maximum absolute charge of Qmax = 10, assuming that the chiral superfield content of the model is that of the MSSM plus up to three Standard Model (SM) singlet superfields. The fermionic components of these SM singlets may play the rôle of right-handed neutrinos, whereas one of the scalar components may play the rôle of the flavon, spontaneously breaking U(1)X. Easily scanned lists of the charge assignments are made publicly available on Zenodo. For the case where no restriction is placed upon Qmax, we also provide an analytic parameterisation of the general solution using simple techniques from algebraic geometry. [ABSTRACT FROM AUTHOR]

Chiral magnetic insulators manifest novel phases of matter where the sense of rotation of the magnetization is associated with exotic transport phenomena. Effective control of such phases and their dynamical evolution points to the search and study of chiral fields like the Dzyaloshinskii–Moriya interaction. Here we combine experiments, numerics, and theory to study a zig-zag dipolar lattice as a model of an interface between magnetic in-plane layers with a perpendicular magnetization. The zig-zag lattice comprises two parallel sublattices of dipoles with perpendicular easy plane of rotation. The dipolar energy of the system is exactly separable into a sum of symmetric and antisymmetric long-range exchange interactions between dipoles, where the antisymmetric coupling generates a nonlocal Dzyaloshinskii–Moriya field which stabilizes winding textures with the form of chiral solitons. The Dzyaloshinskii–Moriya interaction acts as a vector potential or gauge field of the magnetic current and gives rise to emergent magnetic and electric fields that allow the manifestation of the magnetoelectric effect in the system. [ABSTRACT FROM AUTHOR]

This paper uncovers and exploits a link between a central object in harmonic analysis, the so-called Schur functions, and the very hot topic of symmetry protected topological phases of quantum matter. This connection is found in the setting of quantum walks, i.e. quantum analogs of classical random walks. We prove that topological indices classifying symmetry protected topological phases of quantum walks are encoded by matrix Schur functions built out of the walk. This main result of the paper reduces the calculation of these topological indices to a linear algebra problem: calculating symmetry indices of finite-dimensional unitaries obtained by evaluating such matrix Schur functions at the symmetry protected points ± 1 . The Schur representation fully covers the complete set of symmetry indices for 1D quantum walks with a group of symmetries realizing any of the symmetry types of the tenfold way. The main advantage of the Schur approach is its validity in the absence of translation invariance, which allows us to go beyond standard Fourier methods, leading to the complete classification of non-translation invariant phases for typical examples. [ABSTRACT FROM AUTHOR]

We study the gravitational-wave signal stemming from strongly coupled models featuring both, dark chiral and confinement phase transitions. We therefore identify strongly coupled theories that can feature a first-order phase transition. Employing the Polyakov-Nambu-Jona-Lasinio model, we focus our attention on SU(3) Yang-Mills theories featuring fermions in fundamental, adjoint, and two-index symmetric representations. We discover that for the gravitational-wave signals analysis, there are significant differences between the various representations. Interestingly we also observe that the two-index symmetric representation leads to the strongest first-order phase transition and therefore to a higher chance of being detected by the Big Bang Observer experiment. Our study of the confinement and chiral phase transitions is further applicable to extensions of the Standard Model featuring composite dynamics. [ABSTRACT FROM AUTHOR]

Very recently, the LHCb Collaboration at the Large Hadron Collider at CERN observed new resonance X(4630). The X(4630) is decoded as a charmoniumlike molecule with hidden-strange quantum number well in the one-boson-exchange mechanism. Especially, the study of its hidden-charmed decays explicitly shows the dominant role of J / ψ ϕ among all allowed hidden-charmed decays of the X(4630), which enforces the conclusion of X(4630) as a charmoniumlike molecule. The discovery of the X(4630) is a crucial step of constructing charmoniumlike molecule zoo. [ABSTRACT FROM AUTHOR]

Many candidates of the so-called exotic hadrons have been observed experimentally and most of them are located close to the threshold of a pair of hadrons. The general behavior of the near-threshold line shapes of invariant mass distributions is discussed. To be precise, the threshold cusp can show up as a peak only for channels with attractive interaction, and the width of the cusp is inversely proportional to the reduced mass relevant for the threshold. We argue that there should be (near-)threshold structures for any pair of heavy-quark and heavy-antiquark hadrons, which have attractive interaction at threshold, in the invariant mass distribution of a heavy quarkonium and light hadrons that couple to that open-flavor hadron pair. Predictions of the possible pairs that have near-threshold peaks are given for the ground state heavy hadrons based on the interaction saturated by vector mesons. We also give a survey of the possible hadronic molecules composed of a pair of charmed-anticharmed hadrons by solving the Bethe-Salpeter equation with constant interactions and the experimental candidates of hadronic molecules fit this spectrum well. [ABSTRACT FROM AUTHOR]

We study and present the results of curvature for different symmetry classes (BDI, AIII and A) of model Hamiltonians and also present the transformation of model Hamiltonian from one distinct symmetry class to the other based on the curvature property. We observe the mirror symmetric curvature for the Hamiltonian with BDI symmetry class but there is no evidence of such behaviour for Hamiltonians of AIII symmetry class. We show the origin of torsion and its consequences on the parameter space of topological phase of the system. We find the evidence of torsion for the Hamiltonian of A symmetry class. We present Serret–Frenet equations for all model Hamiltonians in R 3 space. To the best of our knowledge, this is the first application of curvature theory to the model Hamiltonian of different symmetry classes which belong to the topological state of matter. [ABSTRACT FROM AUTHOR]

Decreasing the partition coefficient (LogP) by the introduction of a hydrophilic group is the conventional approach for improving the aqueous solubility of drug candidates, but is not always effective. Since melting point is related to aqueous solubility, we and other groups have developed alternative strategies to improve solubility by means of chemical modification to weaken intermolecular interaction in the solid state, thereby lowering the melting point and increasing the solubility. Here, we show that converting the symmetrical molecular structure of the clinically used estrogen receptor (ER) antagonist cyclofenil (1) into asymmetrical form by introducing an alkyl group enhances the aqueous solubility. Among the synthesized analogs, the chiral methylated analog (R)-4c shows the highest solubility, being 3.6-fold more soluble than 1 even though its hydrophobicity is increased by the methylation. Furthermore, (R)-4c also showed higher membrane permeability than 1, while retaining a comparable metabolic rate, and equivalent biological activity of the active forms (R)-13a to 2. Further validation of this strategy using lead compounds having symmetric structures is expected. [ABSTRACT FROM AUTHOR]

In recent years, bimetallic and trimetallic nanoparticles (NPs) have become attractive materials for many researchers especially in the field of catalysis due to their interesting physical and chemical properties. These unique properties arise mainly from simultaneous effects of two different metal atoms in their structure. In this review, recent theoretical studies on these NPs using molecular dynamics simulation are presented. Since investigation of thermodynamic stabilities of metallic NPs is a critical factor in their construction for catalytic applications, our focus in this review is on the thermal stability of bimetallic and trimetallic NPs. The melting behavior of these materials with different atomic arrangements including core–shell, three-shell, crown-jewel, ordered and disordered alloy, and Janus materials are discussed. Other factors including stress, strain, atomic radius, thermal expansion coefficient, cohesive energy, surface energy, size, composition, and morphology are described in detail, because these properties lead to complexity in the melting behavior of bimetallic and trimetallic NPs. [ABSTRACT FROM AUTHOR]

The standard way to demonstrate the relevance of chiral symmetry for the NN interaction is to consider higher partial waves of NN scattering which are controlled entirely by chiral pion-exchanges (since contacts vanish). However, in applications of NN-potentials to nuclear structure and reactions, the lower partial waves are the important ones, making the largest contributions. Lower partial waves are sensitive to the short-range potential, and so, when the short-range contacts were to dominate over the chiral pion-contributions in lower partial waves, then the predictions from "chiral potentials" would have little to do with chiral symmetry. To address this issue, we investigate systematically the role of the (chiral) one- and two-pion exchanges, on the one hand, and the effect of the contacts, on the other hand, in the lower partial waves of NN scattering. We are able to clearly identify the signature of chiral symmetry in lower partial waves. Our study has also a pedagogical spin-off as it demonstrates in detail how the reproduction of the lower partial-wave phase shifts comes about from the various ingredients of the theory. [ABSTRACT FROM AUTHOR]

In this work, we preform a systematic investigation about hidden heavy and doubly heavy molecular states from the D (∗) D ¯ (∗) / B (∗) B ¯ (∗) and D (∗) D (∗) / B ¯ (∗) B ¯ (∗) interactions in the quasipotential Bethe–Salpeter equation (qBSE) approach. With the help of Lagrangians with heavy quark and chiral symmetries, interaction potentials are constructed within the one-boson-exchange model in which we include the π , η , ρ , ω and σ exchanges, as well as J / ψ or Υ exchange. Possible bound states from the interactions considered are searched for as the pole of scattering amplitude. The results suggest that experimentally observed states, Z c (3900) , Z c (4020) , Z b (10610) , and Z b (10650) , can be related to the D D ¯ ∗ , D ∗ D ¯ ∗ , B B ¯ ∗ , and B ∗ B ¯ ∗ interactions with quantum numbers I G (J P) = 1 + (1 +) , respectively. The D D ¯ ∗ interaction is also attractive enough to produce a pole with 0 + (0 +) which is related to the X(3872). Within the same theoretical frame, the existence of D D ¯ and B B ¯ molecular states with 0 (0 +) are predicted. The possible D ∗ D ¯ ∗ molecular states with 0 (0 + , 1 + , 2 +) and 1 (0 +) and their bottom partners are also suggested by the calculation. In the doubly heavy sector, no bound state is produced from the D D / B ¯ B ¯ interaction while a bound state is found with 0 (1 +) from D D ∗ / B ¯ B ¯ ∗ interaction. The D ∗ D ∗ / B ¯ ∗ B ¯ ∗ interaction produces three molecular states with 0 (1 +) , 0 (2 +) and 1 (2 +) . [ABSTRACT FROM AUTHOR]

A perfect star packing in a graph G is a spanning subgraph of G whose every component is isomorphic to the star graph K 1 , 3 . We investigate which fullerene graphs allow such packings. We also consider generalized fullerene graphs and packings of other graphs into classical and generalized fullerenes. Several open problems are listed. [ABSTRACT FROM AUTHOR]

The B p -algebras are a family of vertex operator algebras parameterized by p ∈ Z ≥ 2 . They are important examples of logarithmic CFTs and appear as chiral algebras of type (A 1 , A 2 p - 3) Argyres–Douglas theories. The first member of this series, the B 2 -algebra, are the well-known symplectic bosons also often called the β γ vertex operator algebra. We study categories related to the B p vertex operator algebras using their conjectural relation to unrolled restricted quantum groups of sl 2 . These categories are braided, rigid and non semi-simple tensor categories. We list their simple and projective objects, their tensor products and their Hopf links. The latter are succesfully compared to modular data of characters thus confirming a proposed Verlinde formula of David Ridout and the second author. [ABSTRACT FROM AUTHOR]

We studied chiral phase transition in the linear sigma model within the Tsallis nonextensive statistics under some approximations. The statistics has two parameters: the temperature T and the entropic parameter q. The normalized q-expectation value and the physical temperature T ph were employed in this study. The normalized q-expectation value was expanded as a series of the value (1 - q) , where the absolute value | 1 - q | is the measure of the deviation from the BG statistics. We applied the Hartree factorization and the free particle approximation, and obtained the equations for the condensate, the sigma mass, and the pion mass. The physical temperature dependences of these quantities were obtained numerically. We found following facts. The condensate at q is smaller than that at q ′ for q > q ′ . The sigma mass at q is lighter than that at q ′ for q > q ′ at low physical temperature, and the sigma mass at q is heavier than that at q ′ for q > q ′ at high physical temperature. The pion mass at q is heavier than that at q ′ for q > q ′ . The difference between the pion masses at different values of q is small for T ph ≤ 200 MeV. In other words, the condensate and the sigma mass are affected by the Tsallis nonextensive statistics with | 1 - q | = 0.1 , and the pion mass is also affected by the statistics of | 1 - q | = 0.1 except for T ph ≤ 200 MeV. [ABSTRACT FROM AUTHOR]

N = 1 supersymmetric SU(N) × SU(N + M) cascading gauge theory of Klebanov et al. [1-2] spontaneously breaks chiral symmetry in Minkowski space-time. We demonstrate that in de Sitter space-time the chiral symmetry breaking occurs for the values of the Hubble constant H < ~ 0.7 Λ , as well as in the narrow window 0.92(1)Λ ≤ H ≤ 0.92(5)Λ. We give a precise definition of the strong coupling scale A of the cascading gauge theory, which is related to the glueball mass scale in the theory mglueball and the asymptotic string coupling gs as Λ ~ g s 1 / 2 mgluebal.l [ABSTRACT FROM AUTHOR]

In AgCu nanoalloys a size-dependent transition to the chiral stacking from the anti-Mackay stacking has been predicted previously. This trend is explained by considering the interplay between the core-shell energetics. Results indicate that the energy changes in the Ag shell alone is not sufficient to explain the stability of the chiral stacking and the energy changes in the Cu core also need to be considered. In addition to this, thermally induced transition to chiral stacking was observed at sizes where anti-Mackay stacking is energetically favourable. On transition to the chiral stacking, the Ag-Ag, Ag-Cu and Cu-Cu bond lengths change significantly. These observations are also applicable for AgCu nanoalloys with incomplete Ag shells. [ABSTRACT FROM AUTHOR]

Abstract: Chiral semiconductor nanoscrolls are promising materials for applications in chiral chemistry, biomedicine, and spintronics. Despite a large number of studies on the formation of nanoscrolls, there is lack of consistent theory of their optical and chiroptical properties. In this paper, we propose a simple analytical model of semiconductor nanoscrolls, based on the original coordinate transformation method and two-band effective mass approximation. This model allows to simulate absorption and circular dichroism spectra of nanoscroll of given geometry and material composition and to analyze experimental data. [ABSTRACT FROM AUTHOR]

The combination of profound chirality and high symmetry on the nm-scale is unusual and would open exciting avenues, both fundamental and applied. Here we show how the unique electronic structure and bonding of quasi-2D gold makes this possible. We report a chiral symmetry breaking, i.e., the spontaneous formation of a chiral-icosahedral shell (I-Au60) from achiral (Uh) precursor forms, accompanied by a contraction in the Au-Au bonding and hence the radius of this perfect golden sphere, in which all 60 sites are chemically equivalent. This structure, which resembles the most complex of semi-regular (Archimedean) polyhedra (34.5*), may be viewed as an optimal solution to the topological problem: how to close a 60-vertex 2D (triangular) net in 3D. The singular rigidity of the I-Au60 manifests in uniquely discrete structural, vibrational, electronic, and optical signatures, which we report herein as a guide to its experimental detection and ultimately its isolation in material forms. [ABSTRACT FROM AUTHOR]

We investigate the resonant regime of a mesoscopic cavity made of graphene or a doped beam splitter. Using Non-Hermitian Quantum Mechanics, we consider the Bender-Boettcher assumption that a system must obey parity and time reversal symmetry. Therefore, we describe such system by coupling chirality, parity, and time reversal symmetries through the scattering matrix formalism and apply it in the shot noise functions, also derived here. Finally, we show how to achieve the resonant regime only by setting properly the parameters concerning the chirality and the PT symmetry. [ABSTRACT FROM AUTHOR]

We analyze neutrinoless double beta decay (0 νββ) within the framework of the Standard Model Effective Field Theory. Apart from the dimension-five Weinberg operator, the first contributions appear at dimension seven. We classify the operators and evolve them to the electroweak scale, where we match them to effective dimension-six, -seven, and -nine operators. In the next step, after renormalization group evolution to the QCD scale, we construct the chiral Lagrangian arising from these operators. We develop a power-counting scheme and derive the two-nucleon 0 νββ currents up to leading order in the power counting for each lepton-number-violating operator. We argue that the leading-order contribution to the decay rate depends on a relatively small number of nuclear matrix elements. We test our power counting by comparing nuclear matrix elements obtained by various methods and by different groups. We find that the power counting works well for nuclear matrix elements calculated from a specific method, while, as in the case of light Majorana neutrino exchange, the overall magnitude of the matrix elements can differ by factors of two to three between methods. We calculate the constraints that can be set on dimension-seven lepton-number-violating operators from 0 νββ experiments and study the interplay between dimension-five and -seven operators, discussing how dimension-seven contributions affect the interpretation of 0 νββ in terms of the effective Majorana mass m . [ABSTRACT FROM AUTHOR]

The theoretical studies of phase states with a linear dispersion of the spectrum of low-energy electron excitations have been reviewed. Some main properties and methods of experimental study of these states in socalled Dirac materials have been discussed in detail. The results of modern studies of symmetry-protected electronic states with nontrivial topology have been reported. Combination of approaches based on geometry with homotopic topology methods and results of condensed matter physics makes it possible to clarify new features of topological insulators, as well as Dirac and Weyl semimetals. [ABSTRACT FROM AUTHOR]

The notion of a topological phase of an insulator is based on the concept of homotopy between Hamiltonians. It therefore depends on the choice of a topological space to which the Hamiltonians belong. We advocate that this space should be the $$C^*$$ -algebra of observables. We relate the symmetries of insulators to graded real structures on the observable algebra and classify the topological phases using van Daele's formulation of K-theory. This is related but not identical to Thiang's recent approach to classify topological phases by K-groups in Karoubi's formulation. [ABSTRACT FROM AUTHOR]

Derivatives of natural diterpenoid methyl lambertianate containing propargyloxy substituents in 16,17-positions were obtained. CuAAC reaction of methyl 17-propargyloxy-16-[(prop-2-yn-1-yloxy)methyl]labdadienoate with various diazides in the presence of Cu(II)/sodium ascorbate in methylene chloride/water reaction medium gave chiral macrocyclic compounds connected on the 16 and 17-positions by 1,2,3-triazole rings with methylene, ethyloxyethyl or ethylethoxyethyl units. The obtained macrocyclic structures showed high selectivity and affinity for Hg ion by the 1,2,3-triazole rings. [ABSTRACT FROM AUTHOR]

The chiral symmetry in complex chemical systems containing many amino acids and characterized by many similar chemical reactions (a situation corresponding to the formation of life on Earth) is considered. It is shown that effective averaging over similar reaction channels may lead to very weak effective enantioselectivity, which does not allow for chiral symmetry breaking in most known models. A class of models with simple and catalytic synthesis of one amino acid, the formation of peptides with a length reaching three, and the precipitation of one insoluble pair of materials is analyzed. It is proven that chiral symmetry breaking may occur in one possible version from an insoluble pair of materials even in the complete absence of catalytic synthesis of amino acid. It is shown that the presence of weakly enantioselective catalytic synthesis in a model significantly increases the number of possible versions in which chiral symmetry breaks. [ABSTRACT FROM AUTHOR]