In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contri...In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contributions from the direct instantons. The numerical results indicate that the contributions from the direct instantons are very small and can be safely neglected.展开更多
Employing a 4-form ansatz of 11-dimensional supergravity over a non-dynamical AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent truncation.The(pseu...Employing a 4-form ansatz of 11-dimensional supergravity over a non-dynamical AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent truncation.The(pseudo)scalars,in the resulting scalar equations in Euclidean AdS_(4)space,may be considered to arise from(anti)M-branes wrapping around the internal directions in the(Wick-rotated)skew-whiffed M2-brane background(as the resulting theory is for anti-M2-branes),thus realizing the modes after swapping the three fundamental representations 8_(s),8_(c),and 8_(v) of SO(8).Taking the backreaction on the external and internal spaces,we obtain the massless and massive modes,corresponding to exactly marginal and marginally irrelevant deformations on the boundary CFT3,respectively.Subsequently,we obtain a closed solution for the bulk equation and compute its correction with respect to the background action.Next,considering the Higgs-like(breathing)mode m^(2)=18,having all supersymmetries as well as parity and scale-invariance broken,solving the associated bulk equation with mathematical methods,specifically the Adomian decomposition method,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the SU(4)×U(1)-singlet sectors of the ABJM model.Then,introducing the new dual deformationΔ_(+)=3,6 operators made of bi-fundamental scalars,fermions,and U(1)gauge fields,we obtain the SO(4)-invariant solutions as small instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.展开更多
We discuss the Atiyah-Drinfeld-Hitchin-Manin （ADHM） construc- tion of U（N） instantons in noncommutative （NC） space and give some exact instanton solutions for various noncommutative settings. We also present a n...We discuss the Atiyah-Drinfeld-Hitchin-Manin （ADHM） construc- tion of U（N） instantons in noncommutative （NC） space and give some exact instanton solutions for various noncommutative settings. We also present a new formula which is crucial to show an origin of the instanton number for U（1） and to prove the one-to-one correspondence between moduli spaces of the noncommutative instantons and the ADHM data.展开更多
We discuss possible implications of exotic stringy instantons for baryon-violating signatures in future colliders. In particular, we discuss high-energy quark collisions and A- transitions. In principle, the A-A proce...We discuss possible implications of exotic stringy instantons for baryon-violating signatures in future colliders. In particular, we discuss high-energy quark collisions and A- transitions. In principle, the A-A process can be probed by high-luminosity electron-positron colliders. However, we find that an extremely high luminosity is needed in order to provide a （somewhat） stringent bound compared to the current data on NN→ππ,KK. On the other hand, （exotic） instanton-induced six-quark interactions can be tested in near future high-energy colliders beyond LHC, at energies around 20-100 TeV. The Super proton-proton Collider （SppC） would be capable of such measurement given the proposed energy level of 50-90 TeV. Comparison with other channels is made. In particular, we show the compatibility of our model with neutron-antineutron and NN→ππ, KK bounds.展开更多
Considering the importance of higher-dimensional equations that are widely applied to real nonlinear problems,many(4+1)-dimensional integrable systems have been established by uplifting the dimensions of their corresp...Considering the importance of higher-dimensional equations that are widely applied to real nonlinear problems,many(4+1)-dimensional integrable systems have been established by uplifting the dimensions of their corresponding lower-dimensional integrable equations.Recently,an integrable(4+1)-dimensional extension of the Boiti-Leon-Manna-Pempinelli(4DBLMP)equation has been proposed,which can also be considered as an extension of the famous Korteweg-de Vries equation that is applicable in fluids,plasma physics and so on.It is shown that new higher-dimensional variable separation solutions with several arbitrary lowerdimensional functions can also be obtained using the multilinear variable separation approach for the 4DBLMP equation.In addition,by taking advantage of the explicit expressions of the new solutions,versatile(4+1)-dimensional nonlinear wave excitations can be designed.As an illustration,periodic breathing lumps,multi-dromion-ring-type instantons,and hybrid waves on a doubly periodic wave background are discovered to reveal abundant nonlinear structures and dynamics in higher dimensions.展开更多
Based on a semi-classical expansion for quantum chromodynamics in the instanton liquid background, the correlation function of the 0^＋＋ scalar glueball current is calculated. Besides the pure classical and quantum c...Based on a semi-classical expansion for quantum chromodynamics in the instanton liquid background, the correlation function of the 0^＋＋ scalar glueball current is calculated. Besides the pure classical and quantum contributions, the contributions arising from the interactions between the classical instanton fields and quantum gluon ones come into play. It turns out that the latter contributions have a great role not only in making the stabilization of the subtracted and unsubtracted Laplace-transformed QCD sum rules for 0^＋＋ scalar glueball, but also in bring back the consistency between the two related sum rules, or equivalently between the QCD asymptotic expression and low energy theorem. The result for the scalar glueball mass is predicted to be mG= 1.35 GeV.展开更多
We study the Schwinger mechanism in the presence of an additional uniformly oriented,weak super Gaussian of integer order 4 N+2.Using the worldline approach,we determine the relevant critical points to compute the lea...We study the Schwinger mechanism in the presence of an additional uniformly oriented,weak super Gaussian of integer order 4 N+2.Using the worldline approach,we determine the relevant critical points to compute the leading order exponential factor analytically.We show that increasing the parameter N gives rise to a strong dynamical enhancement.For N=2,this effect turns out to be larger compared to a weak contribution of the Sauter type.For higher orders,specifically,for the rectangular barrier limit,i.e.N→∞,we approach the Lorentzian case as an upper bound.Although the mentioned backgrounds significantly differ in Minkowski spacetime,we show that the found coincidence applies due to identical reflection points in the Euclidean instanton plane.In addition,we also treat the background in perturbation theory following recent ideas.By doing so,we show that the parameter N determines whether the weak contribution behaves perturbatively or nonperturbatively with respect to the field strength ratio,and,hence,reveals an interesting dependence on the background shape.In particular,we show that for backgrounds,for which higher orders in the field strength ratio turn out to be relevant,a proposed integral condition is not fulfilled.In view of these findings,the latter may serve as an indicator for the necessity for higher-order contributions.展开更多
We investigate the spectrum and decay rates of charmonium states within the framework of the non relativistic quark model by employing a Coulomb like potential from the perturbative one gluon exchange and the linear c...We investigate the spectrum and decay rates of charmonium states within the framework of the non relativistic quark model by employing a Coulomb like potential from the perturbative one gluon exchange and the linear confining potential along with the potential derived from instanton vacuum to account for the hyperfine mass splitting of charmonium states in variational approach. We predict radiative E1, M1, two-photon, lepton and two-gluon decay rates of low lying charmonium states. An overall agreement is obtained with the experimental masses and decay widths.We have estimated the branching ratio of two gluons decaying into light hadrons.展开更多
We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The n...We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The numerical value of the mass mx= （1.66 =k 0.14） GeV is consistent with the experimental data. There might be some tetraquark components in the vector meson X（1576）.展开更多
Under condition of four potential fields, equations of motion and fluctuations in imaginary time are utilized to analytically derive the basic and fluctuating periodic instantons. It is shown that the basic instantons...Under condition of four potential fields, equations of motion and fluctuations in imaginary time are utilized to analytically derive the basic and fluctuating periodic instantons. It is shown that the basic instantons satisfy the elliptic or simple pendulum equations and their solutions are Jacobi elliptic functions, and fluctuating periodic instantons satisfy the Lam′e equation and their solutions are Lame functions. These results indicate that there exists the common solution family for different potential fields which are called the super-symmetry family.展开更多
The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model （RHM）. The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator po...The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model （RHM）. The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator potential, the confined-one-gluon-exchange potential （COGEP） and the instanton-induced quark-antiquak interaction （Ⅲ）. A good description of the mass spectrum is obtained. The respective role of Ⅲ and COGEP in the S-wave meson spectrum is discussed.展开更多
In this manuscript,a reduced(3+1)-dimensional nonlinear evolution equation is studied.We first construct the bilinear formalism of the equation by using the binary Bell polynomials theory,then explore a lump solution ...In this manuscript,a reduced(3+1)-dimensional nonlinear evolution equation is studied.We first construct the bilinear formalism of the equation by using the binary Bell polynomials theory,then explore a lump solution to the special case for z=x.Furthermore,a more general form of lump solution of the equation is found which possesses seven arbitrary parameters and four constraint conditions.By cutting the lump by the induced soliton(s),lumpoff and instanton/rogue wave solutions are also constructed by the more general form of lump solution.展开更多
The(2 + 1)-dimensional Ito equation is extended to a general form including some nonintegrable effects via introducing generalized bilinear operators. It is pointed out that the nonintegrable(2 + 1)-dimensional Ito eq...The(2 + 1)-dimensional Ito equation is extended to a general form including some nonintegrable effects via introducing generalized bilinear operators. It is pointed out that the nonintegrable(2 + 1)-dimensional Ito equation contains lump solutions and interaction solutions between lump and stripe solitons. The result shows that the lump soliton will be swallowed or arisen by a stripe soliton in a fixed time. Furthermore, by the interaction between a lump and a paired resonant stripe soliton, the lump will be transformed to an instanton or a rogue wave.展开更多
The instanton induced cross section in deep inelastic kinematics is a subject which people are tendentious to investigate it. Instanton induced contributions are well defined for the nucleon structure function. The no...The instanton induced cross section in deep inelastic kinematics is a subject which people are tendentious to investigate it. Instanton induced contributions are well defined for the nucleon structure function. The non-perturbative contribution to the quark distributions of structure function, F2（x, Q2）, is considered within an instanton model for the QCD vacuum. We find that the structure function may possess numerically large non-perterbative contributions which are related to the violation of chirality and correspond to the correction of parton distribution of the leading twist. It is shown that the instantons give a negative contribution to the structure function at the NLO approximation. A comparison between our results, considering instantaon effect, and the case when we do not take this effect is done. Taking into account the instanton size, p, via the modified running coupling constant we get to a good agreement between our results at the NLO and NNLO approximations and the available experimental data, specially at the low values of the Bjorken variable x 〈 0.1 which confirms the validity of our calculations.展开更多
APE smearing and overlap-Dirac operator are combined to filter vacuum configurations. The structures of vacuum are studied by low-lying eigenmodes of the overlap-Dirac operator, which exhibits that instanton liquid mo...APE smearing and overlap-Dirac operator are combined to filter vacuum configurations. The structures of vacuum are studied by low-lying eigenmodes of the overlap-Dirac operator, which exhibits that instanton liquid model can be used.展开更多
Gluon propagator is investigated for pure Yang-Mills SU(3) gauge theory in field-strength approach. It isfound that instantohs provide a homogeneous solid-like medium background which generates finite nonzero momentum...Gluon propagator is investigated for pure Yang-Mills SU(3) gauge theory in field-strength approach. It isfound that instantohs provide a homogeneous solid-like medium background which generates finite nonzero momentumgluon propagator and gluon receives effective mass.展开更多
There are two distinct phases in the evolution of drift wave envelope in the presence of zonal flow.A long-lived standing wave phase,which we call the Caviton,and a short-lived traveling wave phase(in radial direction...There are two distinct phases in the evolution of drift wave envelope in the presence of zonal flow.A long-lived standing wave phase,which we call the Caviton,and a short-lived traveling wave phase(in radial direction) we call the Instanton.Several abrupt phenomena observed in tokamaks,such as intermittent excitation of geodesic acoustic mode(GAM) shown in this paper,could be attributed to the sudden and fast radial motion of Instanton.The composite drift wave-zonal flow system evolves at the two well-separate scales:the micro-scale and the meso-scale.The eigenmode equation of the model defines the zero-order(micro-scale) variation;it is solved by making use of the two-dimensional(2 D) weakly asymmetric ballooning theory(WABT),a theory suitable for modes localized to rational surface like drift waves,and then refined by shifted inverse power method,an iterative finite difference method.The next order is the equation of electron drift wave(EDW) envelope(containing group velocity of EDW) which is modulated by the zonal flow generated by Reynolds stress of EDW.This equation is coupled to the zonal flow equation,and numerically solved in spatiotemporal representation;the results are displayed in self-explanatory graphs.One observes a strong correlation between the Caviton-Instanton transition and the zero-crossing of radial group velocity of EDW.The calculation brings out the defining characteristics of the Instanton:it begins as a linear traveling wave right after the transition.Then,it evolves to a nonlinear stage with increasing frequency all the way to 20 kHz.The modulation to Reynolds stress in zonal flow equation brought in by the nonlinear Instanton will cause resonant excitation to GAM.The intermittency is shown due to the random phase mixing between multiple central rational surfaces in the reaction region.展开更多
We propose a systematic way of finding solutions to the classical Yang–Mills equation with nontrivial topology. This approach is based on one of the Wightman axioms for quantum field theory, which is referred to as t...We propose a systematic way of finding solutions to the classical Yang–Mills equation with nontrivial topology. This approach is based on one of the Wightman axioms for quantum field theory, which is referred to as the form invariance condition in this paper. For a given gauge group and a spacetime with certain isometries, thanks to this axiom that imposes strong constraints on the general ansatz, a systematic way of solving the Yang–Mills equation can be obtained in both flat and curved spacetimes. In order to demonstrate this method, we recover various known solutions as special cases, as well as producing new solutions not previously reported in the literature.展开更多
Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the top...Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the topological charge and identify the structure of the vacuum. The results are consistent with instanton liquid model .展开更多
Following the approach of our previous paper we continue to study the asymptotic solution of periodic Schrodinger operators. Using the eigenvalues obtained earlier the corresponding asymptotic wave functions are deriv...Following the approach of our previous paper we continue to study the asymptotic solution of periodic Schrodinger operators. Using the eigenvalues obtained earlier the corresponding asymptotic wave functions are derived. This gives further evidence in favor of the monodromy relations for the Floquet exponent proposed in the previous paper. In particular, the large energy asymptotic wave functions are related to the instanton partition function of N = 2 supersymmetric gauge theory with surface operator. A relevant number theoretic dessert is appended.展开更多
基金The project supported by National Natural Science Foundation of China under Grant No. 10405009 and the Key Program Foundation of North China Electric Power University
文摘In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contributions from the direct instantons. The numerical results indicate that the contributions from the direct instantons are very small and can be safely neglected.
文摘Employing a 4-form ansatz of 11-dimensional supergravity over a non-dynamical AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent truncation.The(pseudo)scalars,in the resulting scalar equations in Euclidean AdS_(4)space,may be considered to arise from(anti)M-branes wrapping around the internal directions in the(Wick-rotated)skew-whiffed M2-brane background(as the resulting theory is for anti-M2-branes),thus realizing the modes after swapping the three fundamental representations 8_(s),8_(c),and 8_(v) of SO(8).Taking the backreaction on the external and internal spaces,we obtain the massless and massive modes,corresponding to exactly marginal and marginally irrelevant deformations on the boundary CFT3,respectively.Subsequently,we obtain a closed solution for the bulk equation and compute its correction with respect to the background action.Next,considering the Higgs-like(breathing)mode m^(2)=18,having all supersymmetries as well as parity and scale-invariance broken,solving the associated bulk equation with mathematical methods,specifically the Adomian decomposition method,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the SU(4)×U(1)-singlet sectors of the ABJM model.Then,introducing the new dual deformationΔ_(+)=3,6 operators made of bi-fundamental scalars,fermions,and U(1)gauge fields,we obtain the SO(4)-invariant solutions as small instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.
文摘We discuss the Atiyah-Drinfeld-Hitchin-Manin （ADHM） construc- tion of U（N） instantons in noncommutative （NC） space and give some exact instanton solutions for various noncommutative settings. We also present a new formula which is crucial to show an origin of the instanton number for U（1） and to prove the one-to-one correspondence between moduli spaces of the noncommutative instantons and the ADHM data.
基金supported in part by the MIUR research grant “Theoretical Astroparticle Physics” PRIN 2012CPPYP7partly supported by the DFG and the NSFC through funds provided to the Sino-German CRC 110 “Symmetries and the Emergence of Structure in QCD”+2 种基金MOST,Taiwan,(104-2112-M-001-022)from April 2017Supported by MEPhI Academic Excellence Project(contract 02.03.21.0005,27.08.2013)supported by the Ministry of Education and Science of Russian Federation,project 3.472.2014/K and grant RFBR 14-22-03048
文摘We discuss possible implications of exotic stringy instantons for baryon-violating signatures in future colliders. In particular, we discuss high-energy quark collisions and A- transitions. In principle, the A-A process can be probed by high-luminosity electron-positron colliders. However, we find that an extremely high luminosity is needed in order to provide a （somewhat） stringent bound compared to the current data on NN→ππ,KK. On the other hand, （exotic） instanton-induced six-quark interactions can be tested in near future high-energy colliders beyond LHC, at energies around 20-100 TeV. The Super proton-proton Collider （SppC） would be capable of such measurement given the proposed energy level of 50-90 TeV. Comparison with other channels is made. In particular, we show the compatibility of our model with neutron-antineutron and NN→ππ, KK bounds.
基金supported by the National Natural Science Foundation of China (Grant Nos.12275085 and 12235007)the Science and Technology Commission of Shanghai Municipality (Grant No.22DZ2229014)。
文摘Considering the importance of higher-dimensional equations that are widely applied to real nonlinear problems,many(4+1)-dimensional integrable systems have been established by uplifting the dimensions of their corresponding lower-dimensional integrable equations.Recently,an integrable(4+1)-dimensional extension of the Boiti-Leon-Manna-Pempinelli(4DBLMP)equation has been proposed,which can also be considered as an extension of the famous Korteweg-de Vries equation that is applicable in fluids,plasma physics and so on.It is shown that new higher-dimensional variable separation solutions with several arbitrary lowerdimensional functions can also be obtained using the multilinear variable separation approach for the 4DBLMP equation.In addition,by taking advantage of the explicit expressions of the new solutions,versatile(4+1)-dimensional nonlinear wave excitations can be designed.As an illustration,periodic breathing lumps,multi-dromion-ring-type instantons,and hybrid waves on a doubly periodic wave background are discovered to reveal abundant nonlinear structures and dynamics in higher dimensions.
基金Supported by the National Natural Science Foundation of China under Grant No 10075036, the BEPC National Laboratory Project of Research and Development, and the BES Collaboration Research Foundation.
文摘Based on a semi-classical expansion for quantum chromodynamics in the instanton liquid background, the correlation function of the 0^＋＋ scalar glueball current is calculated. Besides the pure classical and quantum contributions, the contributions arising from the interactions between the classical instanton fields and quantum gluon ones come into play. It turns out that the latter contributions have a great role not only in making the stabilization of the subtracted and unsubtracted Laplace-transformed QCD sum rules for 0^＋＋ scalar glueball, but also in bring back the consistency between the two related sum rules, or equivalently between the QCD asymptotic expression and low energy theorem. The result for the scalar glueball mass is predicted to be mG= 1.35 GeV.
基金the support of the Collaborative Research Center SFB 676 of the DFG.
文摘We study the Schwinger mechanism in the presence of an additional uniformly oriented,weak super Gaussian of integer order 4 N+2.Using the worldline approach,we determine the relevant critical points to compute the leading order exponential factor analytically.We show that increasing the parameter N gives rise to a strong dynamical enhancement.For N=2,this effect turns out to be larger compared to a weak contribution of the Sauter type.For higher orders,specifically,for the rectangular barrier limit,i.e.N→∞,we approach the Lorentzian case as an upper bound.Although the mentioned backgrounds significantly differ in Minkowski spacetime,we show that the found coincidence applies due to identical reflection points in the Euclidean instanton plane.In addition,we also treat the background in perturbation theory following recent ideas.By doing so,we show that the parameter N determines whether the weak contribution behaves perturbatively or nonperturbatively with respect to the field strength ratio,and,hence,reveals an interesting dependence on the background shape.In particular,we show that for backgrounds,for which higher orders in the field strength ratio turn out to be relevant,a proposed integral condition is not fulfilled.In view of these findings,the latter may serve as an indicator for the necessity for higher-order contributions.
文摘We investigate the spectrum and decay rates of charmonium states within the framework of the non relativistic quark model by employing a Coulomb like potential from the perturbative one gluon exchange and the linear confining potential along with the potential derived from instanton vacuum to account for the hyperfine mass splitting of charmonium states in variational approach. We predict radiative E1, M1, two-photon, lepton and two-gluon decay rates of low lying charmonium states. An overall agreement is obtained with the experimental masses and decay widths.We have estimated the branching ratio of two gluons decaying into light hadrons.
基金Supported by the National Natural Science Foundation under Grant No 10405009, and the Key Program Foundation of North China Electric Power University.
文摘We take the viewpoint that X（1576） is the tetraquark state which consists of a scalar diquark and an antiscalar-diquark in relative P-wave, and calculate its mass in the framework of the QCD sum rule approach. The numerical value of the mass mx= （1.66 =k 0.14） GeV is consistent with the experimental data. There might be some tetraquark components in the vector meson X（1576）.
基金Supportted by the National Natural Science Foundation of China under Grant No.40975027
文摘Under condition of four potential fields, equations of motion and fluctuations in imaginary time are utilized to analytically derive the basic and fluctuating periodic instantons. It is shown that the basic instantons satisfy the elliptic or simple pendulum equations and their solutions are Jacobi elliptic functions, and fluctuating periodic instantons satisfy the Lam′e equation and their solutions are Lame functions. These results indicate that there exists the common solution family for different potential fields which are called the super-symmetry family.
基金the DST for funding the project (Sanction No.SR/S2/HEP-14/2006)
文摘The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model （RHM）. The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator potential, the confined-one-gluon-exchange potential （COGEP） and the instanton-induced quark-antiquak interaction （Ⅲ）. A good description of the mass spectrum is obtained. The respective role of Ⅲ and COGEP in the S-wave meson spectrum is discussed.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11675084 and 11435005)the Fund from the Educational Commission of Zhejiang Province,China(Grant No.Y201737177)+1 种基金Ningbo Natural Science Foundation(Grant No.2015A610159)the K C Wong Magna Fund in Ningbo University
文摘In this manuscript,a reduced(3+1)-dimensional nonlinear evolution equation is studied.We first construct the bilinear formalism of the equation by using the binary Bell polynomials theory,then explore a lump solution to the special case for z=x.Furthermore,a more general form of lump solution of the equation is found which possesses seven arbitrary parameters and four constraint conditions.By cutting the lump by the induced soliton(s),lumpoff and instanton/rogue wave solutions are also constructed by the more general form of lump solution.
基金Supported by the National Natural Science Foundation of China under Grant No.1143505sponsored by K.C.Wong Magna Fund in Ningbo University
文摘The(2 + 1)-dimensional Ito equation is extended to a general form including some nonintegrable effects via introducing generalized bilinear operators. It is pointed out that the nonintegrable(2 + 1)-dimensional Ito equation contains lump solutions and interaction solutions between lump and stripe solitons. The result shows that the lump soliton will be swallowed or arisen by a stripe soliton in a fixed time. Furthermore, by the interaction between a lump and a paired resonant stripe soliton, the lump will be transformed to an instanton or a rogue wave.
文摘The instanton induced cross section in deep inelastic kinematics is a subject which people are tendentious to investigate it. Instanton induced contributions are well defined for the nucleon structure function. The non-perturbative contribution to the quark distributions of structure function, F2（x, Q2）, is considered within an instanton model for the QCD vacuum. We find that the structure function may possess numerically large non-perterbative contributions which are related to the violation of chirality and correspond to the correction of parton distribution of the leading twist. It is shown that the instantons give a negative contribution to the structure function at the NLO approximation. A comparison between our results, considering instantaon effect, and the case when we do not take this effect is done. Taking into account the instanton size, p, via the modified running coupling constant we get to a good agreement between our results at the NLO and NNLO approximations and the available experimental data, specially at the low values of the Bjorken variable x 〈 0.1 which confirms the validity of our calculations.
基金The project supported in part by the Key Research Plan of Theoretical Physics and Cross Science under Grant No. 90103018.
文摘APE smearing and overlap-Dirac operator are combined to filter vacuum configurations. The structures of vacuum are studied by low-lying eigenmodes of the overlap-Dirac operator, which exhibits that instanton liquid model can be used.
文摘Gluon propagator is investigated for pure Yang-Mills SU(3) gauge theory in field-strength approach. It isfound that instantohs provide a homogeneous solid-like medium background which generates finite nonzero momentumgluon propagator and gluon receives effective mass.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1967206,11975231,11805203,and 11775222)the National MCF Energy Research and Development Program,China(Grant Nos.2018YFE0311200 and 2017YFE0301204)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDB-SSW-SYS004)。
文摘There are two distinct phases in the evolution of drift wave envelope in the presence of zonal flow.A long-lived standing wave phase,which we call the Caviton,and a short-lived traveling wave phase(in radial direction) we call the Instanton.Several abrupt phenomena observed in tokamaks,such as intermittent excitation of geodesic acoustic mode(GAM) shown in this paper,could be attributed to the sudden and fast radial motion of Instanton.The composite drift wave-zonal flow system evolves at the two well-separate scales:the micro-scale and the meso-scale.The eigenmode equation of the model defines the zero-order(micro-scale) variation;it is solved by making use of the two-dimensional(2 D) weakly asymmetric ballooning theory(WABT),a theory suitable for modes localized to rational surface like drift waves,and then refined by shifted inverse power method,an iterative finite difference method.The next order is the equation of electron drift wave(EDW) envelope(containing group velocity of EDW) which is modulated by the zonal flow generated by Reynolds stress of EDW.This equation is coupled to the zonal flow equation,and numerically solved in spatiotemporal representation;the results are displayed in self-explanatory graphs.One observes a strong correlation between the Caviton-Instanton transition and the zero-crossing of radial group velocity of EDW.The calculation brings out the defining characteristics of the Instanton:it begins as a linear traveling wave right after the transition.Then,it evolves to a nonlinear stage with increasing frequency all the way to 20 kHz.The modulation to Reynolds stress in zonal flow equation brought in by the nonlinear Instanton will cause resonant excitation to GAM.The intermittency is shown due to the random phase mixing between multiple central rational surfaces in the reaction region.
基金supported in part by the U.S.Department of Energy under grant DE-SC0007859a Van Loo Postdoctoral Fellowship.
文摘We propose a systematic way of finding solutions to the classical Yang–Mills equation with nontrivial topology. This approach is based on one of the Wightman axioms for quantum field theory, which is referred to as the form invariance condition in this paper. For a given gauge group and a spacetime with certain isometries, thanks to this axiom that imposes strong constraints on the general ansatz, a systematic way of solving the Yang–Mills equation can be obtained in both flat and curved spacetimes. In order to demonstrate this method, we recover various known solutions as special cases, as well as producing new solutions not previously reported in the literature.
基金The project supported in part by National Natural Science Foundation of China under Grant Nos. 90103018 and 90503011
文摘Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the topological charge and identify the structure of the vacuum. The results are consistent with instanton liquid model .
基金supported by the FAPESP No.2011/21812-8,through IFT-UNESP
文摘Following the approach of our previous paper we continue to study the asymptotic solution of periodic Schrodinger operators. Using the eigenvalues obtained earlier the corresponding asymptotic wave functions are derived. This gives further evidence in favor of the monodromy relations for the Floquet exponent proposed in the previous paper. In particular, the large energy asymptotic wave functions are related to the instanton partition function of N = 2 supersymmetric gauge theory with surface operator. A relevant number theoretic dessert is appended.
