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ON THE EXISTENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to (F(x,u,Du))+integral from n=■Q to (G(x,u))
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作者 严树森 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期231-240,共10页
In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o... In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o to u (g(x,t)dt), under the weak structure conditions on F(x, u, q) by the Mountain Pass Lemma. 展开更多
关键词 ON THE EXISTENCE OF INFINITELY MANY critical points OF THE EVEN FUNCTIONAL integral from n=Q to x u Du ON THE EXISTENCE OF INFINITELY MANY critical points OF THE EVEN FUNCTIONAL integral from n Q to x u
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ASYMPTOTIC EXPANSION OF DIRAC-TYPE DISTRIBUTION ASSOCIATED WITH A CLASS OF HYPERSURFACES WITH DEGENERATED CRITICAL POINTS 被引量:1
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作者 Qi Minyou Zhang Guoping 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期127-137,共11页
In order to generalize Hadamard's theory of fundamental solutions to the case of degenerate holomorphic PDE,this paper studies the asymptotic expansion of Dirac-type distribution associated with a class of hypersu... In order to generalize Hadamard's theory of fundamental solutions to the case of degenerate holomorphic PDE,this paper studies the asymptotic expansion of Dirac-type distribution associated with a class of hypersurfaces F(x)with degenerate critical points and proves that[F(x)](+)(lambda)is a distribution-valued meromorphic of lambda is an element of C under some assumptions on F(x).Next,the authors use the Normal form theory of Arnold and prove that for a hypersurface F(x)=0 with A(mu)type degenerate critical point at x=0,F-+(lambda)is a distribution-valued meromorphic function of lambda. 展开更多
关键词 asymptotic expansion degenerate critical point HYPERSURFACE distribution-valued meromorphic function analytic extension
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Quantitative determination of the critical points of Mott metal–insulator transition in strongly correlated systems
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作者 牛月坤 倪煜 +4 位作者 王建利 陈雷鸣 邢晔 宋筠 冯世平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期647-652,共6页
Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transiti... Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transition in a Hubbard model by using the dynamical mean-field theory and introduce the local quantum state fidelity to depict the Mott metal–insulator transition. The local quantum state fidelity provides a convenient approach to determining the critical point of the Mott transition. Additionally, it presents a consistent description of the two distinct forms of the Mott transition points. 展开更多
关键词 critical point metal–insulator transition local quantum state fidelity strongly correlated system quasiparticle coherent weight
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BIFURCATION PROBLEM OF CRITICAL POINTSFOR QUADRATIC DIFFERENTIAL SYSTEMS
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作者 张祥 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第12期0-0,0-0+0-0+0-0+0-0+0-0+0-0,共14页
In this paper foe bifurcation of critical points for the quadratic systems of type(II)and (III) is investigated. and an answer to the problem given in[1] is given.
关键词 quadratic system DIVERGENCE critical point
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ON THE CRITICAL POINTS OF THE MAP F_p:X→‖AXB-C‖_p^p
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作者 杨长森 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第4期485-488,共4页
Suppose A,B and C are the bounded linear operators on a Hilbert space H, when A has a generalized inverse A - such that (AA -) *=AA - and B has a generalized inverse B - such that (B -B) *=B -B,the general cha... Suppose A,B and C are the bounded linear operators on a Hilbert space H, when A has a generalized inverse A - such that (AA -) *=AA - and B has a generalized inverse B - such that (B -B) *=B -B,the general characteristic forms for the critical points of the map F p:X→‖ A X B-C ‖ p p (1<p<∞), have been obtained, it is a generalization for P J Maher's result about p=2. Similarly, the same question has been discussed for several operators. 展开更多
关键词 generalized inverse critical point polar decomposition
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Deconfined Quantum Critical Point: A Review of Progress
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作者 Yi Cui Rong Yu Weiqiang Yu 《Chinese Physics Letters》 2025年第4期166-176,共11页
Deconfined quantum critical points(DQCPs)have been proposed as a class of continuous quantum phase transitions occurring between two ordered phases with distinct symmetry-breaking patterns,beyond the conventional fram... Deconfined quantum critical points(DQCPs)have been proposed as a class of continuous quantum phase transitions occurring between two ordered phases with distinct symmetry-breaking patterns,beyond the conventional framework of Landau-Ginzburg-Wilson(LGW)theory.At the DQCP,the system exhibits emergent gauge fields,fractionalized excitations,and enhanced symmetries. 展开更多
关键词 deconfined quantum critical points dqcps fractionalized excitations enhanced symmetries emergent gauge fields two ordered phases quantum phase transitions deconfined quantum critical points emergent gauge fieldsfractionalized excitationsand
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Driven Critical Dynamics in the Tricitical Point
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作者 Ting-Long Wang Yi-Fan Jiang Shuai Yin 《Chinese Physics Letters》 2025年第11期1-8,共8页
The conventional Kibble–Zurek mechanism,describing driven dynamics across critical points based on the adiabatic-impulse scenario(AIS),has attracted broad attention.However,the driven dynamics at the tricritical poin... The conventional Kibble–Zurek mechanism,describing driven dynamics across critical points based on the adiabatic-impulse scenario(AIS),has attracted broad attention.However,the driven dynamics at the tricritical point with two independent relevant directions have not been adequately studied.Here,we employ the time-dependent variational principle to study the driven critical dynamics at a one-dimensional supersymmetric Ising tricritical point.For the relevant direction along the Ising critical line,the AIS apparently breaks down.Nevertheless,we find that the critical dynamics can still be described by finite-time scaling in which the driving rate has a dimension of r_(μ)=z+1/v_(μ)with z and v_(μ)being the dynamic exponent and correlation length exponent in this direction,respectively.For driven dynamics along another direction,the driving rate has a dimension of r_(p)=z+1/v_(p)with v_(p)being another correlation length exponent.Our work brings a new fundamental perspective into nonequilibrium critical dynamics near the tricritical point,which could be realized in programmable quantum processors in Rydberg atomic systems. 展开更多
关键词 driven dynamics across critical points finite time scaling dynamic exponent driven dynamics time dependent variational principle Kibble Zurek mechanism tricritical point driven critical dynamics
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QUALITATIVE THEORY OF THE KUKLES SYSTEMS:(Ⅰ) NUMBER OF CRITICAL POINTS 被引量:2
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作者 叶惟寅 叶彦谦 《Annals of Differential Equations》 2001年第3期275-286,共12页
We study the global qualitative properties of the well-known Kukles systems (1) below. Firstly, the number of critical points in case (1) has a center or a fine focus.
关键词 Kukles system critical point CENTER fine focus
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Analysis of Microbial Contamination Factors and Critical Control Points in the Process of Hog Slaughter and Production
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作者 Liu Xiuping Tang Yushun +2 位作者 Liu Yonghua Kou Xu Tang Feng 《Animal Husbandry and Feed Science》 CAS 2015年第4期200-202,共3页
In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control poin... In order to provide a reference for the further study of microbial contamination in the pork production process. Microbial contamination of pigs came from three slaughterhouses were detected, and critical control points in the progress of hog slaughter and processing were analyzed. The results showed that microbial con- taminatian existed in the entire slaughter and processing progress, including shower and assassination bloodletting, separation of the internal organs, chopping boards, workshop environment, personal hygiene of the operators, etc. , which should be paid more attention to. The results indicated that reasonable protection measures should be carried out, disinfection awareness of the operators should be improved, and regular disinfection should be ruled under the condition of continu- ous operation. 展开更多
关键词 Microbial contamination critical control points Hog slaughter
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Linear numerical calculation method for obtaining critical point,pore fluid,and framework parameters of gas-bearing media 被引量:3
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作者 牛滨华 孙春岩 +2 位作者 闫国英 杨维 刘畅 《Applied Geophysics》 SCIE CSCD 2009年第4期319-326,393,共9页
Up to now, the primary method for studying critical porosity and porous media are experimental measurements and data analysis. There are few references on how to numerically calculate porosity at the critical point, p... Up to now, the primary method for studying critical porosity and porous media are experimental measurements and data analysis. There are few references on how to numerically calculate porosity at the critical point, pore fluid-related parameters, or framework-related parameters. So in this article, we provide a method for calculating these elastic parameters and use this method to analyze gas-bearing samples. We first derive three linear equations for numerical calculations. They are the equation of density p versus porosity Ф, density times the square of compressional wave velocity p Vp^2 versus porosity, and density times the square of shear wave velocity pVs^2 versus porosity. Here porosity is viewed as an independent variable and the other parameters are dependent variables. We elaborate on the calculation steps and provide some notes. Then we use our method to analyze gas-bearing sandstone samples. In the calculations, density and P- and S-velocities are input data and we calculate eleven relative parameters for porous fluid, framework, and critical point. In the end, by comparing our results with experiment measurements, we prove the viability of the method. 展开更多
关键词 linear equation numerical calculation gas-bearing media critical point pore fluid and framework elastic parameters
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ON A BI-HARMONIC EQUATION INVOLVING CRITICAL EXPONENT: EXISTENCE AND MULTIPLICITY RESULTS 被引量:4
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作者 Zakaria Boucheche Ridha Yacoub Hichem Chtioui 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1213-1244,共32页
In this paper, we consider the problem of existence as well as multiplicity results for a bi-harmonic equation under the Navier boundary conditions: △2 u = K(x)u p , u 〉 0 in Ω , △u = u = 0 on Ω , where Ω is ... In this paper, we consider the problem of existence as well as multiplicity results for a bi-harmonic equation under the Navier boundary conditions: △2 u = K(x)u p , u 〉 0 in Ω , △u = u = 0 on Ω , where Ω is a smooth domain in R n , n 5, and p + 1 = 2 n n 4 is the critical Sobolev exponent. We obtain highlightly a new criterion of existence, which provides existence results for a dense subset of positive functions, and generalizes Bahri-Coron type criterion in dimension six. Our argument gives also estimates on the Morse index of the obtained solutions and extends some known results. Moreover, it provides, for generic K, Morse inequalities at infinity, which delivers lower bounds for the number of solutions. As further applications of this Morse theoretical approach, we prove more existence results. 展开更多
关键词 critical points at infinity Palais-Smale condition Morse lemma at infinity Morse inequalities
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EXISTENCE AND NONEXISTENCE OF SOLUTIONS FOR A HARMONIC EQUATION WITH CRITICAL NONLINEARITY
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作者 Kamal OULD BOUH 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1305-1316,共12页
This paper is concerned with the harmonic equation(P;) : ?u = 0, u > 0 in B;and ?u/?ν+((n-2)/2)u =((n-2)/2) Ku;on S;where B;is the unit ball in R;, n ≥ 4 with Euclidean metric g;, ?B;= S;is its boundary, K is... This paper is concerned with the harmonic equation(P;) : ?u = 0, u > 0 in B;and ?u/?ν+((n-2)/2)u =((n-2)/2) Ku;on S;where B;is the unit ball in R;, n ≥ 4 with Euclidean metric g;, ?B;= S;is its boundary, K is a function on S;and ε is a small positive parameter. We construct solutions of the subcritical equation(P;) which blow up at one critical point of K. We give also a sufficient condition on the function K to ensure the nonexistence of solutions for(P;) which blow up at one point. Finally, we prove a nonexistence result of single peaked solutions for the supercritical equation(P;). 展开更多
关键词 variational problem critical points harmonic equation mean curvature critical exponent
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Stability of the topological quantum critical point between multi-Weyl semimetal and band insulator
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作者 杨兆昆 王景荣 刘国柱 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期131-140,共10页
One could tune a topological double-Weyl semimetal or a topological triple-Weyl semimetal to become a topologically trivial insulator by opening a band gap.This kind of quantum phase transition is characterized by the... One could tune a topological double-Weyl semimetal or a topological triple-Weyl semimetal to become a topologically trivial insulator by opening a band gap.This kind of quantum phase transition is characterized by the change of certain topological invariant.A new gapless semimetallic state emerges at each topological quantum critical point.Here we perform a renormalization group analysis to investigate the stability of such critical points against perturbations induced by random scalar potential and random vector potential.We find that the quantum critical point between double-Weyl semimetal and band insulator is unstable and can be easily turned into a compressible diffusive metal by any type of weak disorder.The quantum critical point between triple-Weyl semimetal and band insulator flows to a stable strong-coupling fixed point if the system contains a random vector potential merely along the z-axis,but becomes a compressible diffusive metal when other types of disorders exist. 展开更多
关键词 topological quantum critical points Weyl semimetal DISORDER renormalization group
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SOLUTIONS TO DISCRETE MULTIPARAMETER PERIODIC BOUNDARY VALUE PROBLEMS INVOLVING THE p-LAPLACIAN VIA CRITICAL POINT THEORY 被引量:9
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作者 高承华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1225-1236,共12页
In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value ... In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value problems in [C. Bonanno and P. Candito, Appl. Anal., 88(4) (2009), pp. 605-616], we construct two new strong maximum principles and obtain that the boundary value problem has three positive solutions for λ and μ in some suitable intervals. The approaches we use are the critical point theory. 展开更多
关键词 discrete periodic boundary value problem P-LAPLACIAN MULTIPARAMETER three solutions critical point theory
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NONSMOOTH CRITICAL POINT THEOREMS AND ITS APPLICATIONS TO QUASILINEAR SCHRDINGER EQUATIONS 被引量:5
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作者 李周欣 沈尧天 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期73-86,共14页
In this paper, the existence and nonexistence of solutions to a class of quasilinear elliptic equations with nonsmooth functionals are discussed, and the results obtained are applied to quasilinear SchrSdinger equatio... In this paper, the existence and nonexistence of solutions to a class of quasilinear elliptic equations with nonsmooth functionals are discussed, and the results obtained are applied to quasilinear SchrSdinger equations with negative parameter which arose from the study of self-channeling of high-power ultrashort laser in matter. 展开更多
关键词 nonsmooth critical point theorems quasilinear elliptic equations SchrSdingerequation
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Study on Critical Properties for CO_2+Cosolvent Binary System and Ternary System 被引量:2
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作者 张敬畅 吴向阳 曹维良 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第2期223-227,共5页
The performance of supercritical fluid (SCF) as a solvent can be greatly affected by addition of anentrainer to the system. In this study, a constant volume visual method is used to measure the critical point ofCO2+n-... The performance of supercritical fluid (SCF) as a solvent can be greatly affected by addition of anentrainer to the system. In this study, a constant volume visual method is used to measure the critical point ofCO2+n-butyraldehyde, CO2+ i-butyraldehyde and CO2+alcohol binary systems and CO2+entrainer+trisodiumsalt of tri-(m-sulfonphenyl)phosphine (TPPTS) ternary systems, which provides us good theoretical basis for super-critical extraction and chemical reaction. The relationship between critical point and concentration of the entrainerare discussed. The phase behavior of binary system and that of ternary system are compared. The relationshipbetween the concentration of TPPTS and critical point of binary systems are also discussed. 展开更多
关键词 critical point supercritical fluid ternary system phase equilibrium tri-(m-sulfonphenyl)phosphine
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Quasi-exactly solvable decatic model description of nuclei near the X(5)critical point 被引量:1
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作者 Hadi Sobhani Hassan Hassanabadi +2 位作者 Dennis Bonatsos Feng Pan Jerry P Draayer 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第1期46-56,共11页
The Bohr Hamiltonian with axially deformed shape confined in a quasi-exactly solvable decaticβ-part potential is studied.It is shown that the decatic model can well reproduce the X(5)model results as far as the energ... The Bohr Hamiltonian with axially deformed shape confined in a quasi-exactly solvable decaticβ-part potential is studied.It is shown that the decatic model can well reproduce the X(5)model results as far as the energy ratios in the ground and beta band and related B(E2)values are concerned.Fitting results to the low-lying energy ratios and relevant B(E2)values of even-even X(5)candidates^(150)Nd,^(156)Dy,^(164)Yb,^(168)Hf,^(174)Yb,^(176,178,180)Os,and^(188,190)Os show that the decatic model provides the best fitting results for the energy ratios,while the X(5)model is the best at reproducing the B(E2)values of these nuclei,in which the beta-bandhead energy is lower than that of the gamma band.While for even-even nuclei,such as^(154,156,158)Gd,with bandhead energies of the beta and gamma bands more or less equal within the X(5)critical point to the axially deformed region,our numerical analysis indicates that the decatic model is better than the X(5)model in describing both the low-lying level energies and related B(E2)values. 展开更多
关键词 Bohr Hamiltonian the decatic potential X(5)critical point
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A numerical study of fluid injection and mixing under near-critical conditions
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作者 Hua-Guang Li Xi-Yun Lu Vigor Yang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第3期559-571,共13页
Nitrogen injection under conditions close vicinity of the liquid-gas critical point is studied numerically. The fluid thermodynamic and transport properties vary drasti- cally and exhibit anomalies in the near-critica... Nitrogen injection under conditions close vicinity of the liquid-gas critical point is studied numerically. The fluid thermodynamic and transport properties vary drasti- cally and exhibit anomalies in the near-critical regime. These anomalies can cause distinctive effects on heat-transfer and fluid-flow characteristics. To focus on the influence of ther- modynamics on the flow field, a relatively low injection Reynolds number of 1 750 is adopted. For comparisons, a reference case with the same configuration and Reynolds number is simulated in the ideal gas regime. The model accommodates full conservation laws, real-fluid thermody- namic and transport phenomena. Results reveal that the flow features of the near-critical fluid jet are significantly differ- ent from their counterpart. The near-critical fluid jet spreads faster and mixes more efficiently with the ambient fluid along with a more rapidly development of the vortex pairing pro- cess. Detailed analysis at different streamwise locations in- cluding both the flat shear-layer region and fully developed vortex region reveals the important effect of volume dilata- tion and baroclinic torque in the near-critical fluid case. The former disturbs the shear layer and makes it more unstable. The volume dilatation and baroclinic effects strengthen the vorticity and stimulate the vortex rolling up and pairing pro- cess 展开更多
关键词 Liquid-gas critical point Real-fluid Fluid in-jection Shear layer instability Vortical dynamics
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Dynamical signatures of the one-dimensional deconfined quantum critical point
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作者 Ning Xi Rong Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期73-82,共10页
We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product... We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product states.The scaling of the correlation functions and the dispersion of the conserved current correlations explicitly show the emergence of enhanced continuous symmetries at these DQCPs.The dynamical structure factors in several different channels reveal the development of deconfined fractionalized excitations at the DQCPs.Furthermore,we find an effective spin-charge separation at the DQCP between the ferromagnetic(FM)and valence bond solid(VBS)phases,and identify two continua associated with different types of fractionalized excitations at the DQCP between the X-direction and Z-direction FM phases.Our findings not only provide direct evidence for the DQCP in one dimension but also shed light on exploring the DQCP in higher dimensions. 展开更多
关键词 one-dimensional antiferromagnetism spin frustration deconfined quantum critical point spin dynamics infinite time-evolving block decimation
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EXISTENCE OF SOLUTIONS FOR SEMILINEAR ELLIPTIC EQUATIONS INVOLVING CRITICAL SOBOLEV EXPONENTS AND HARDY TERMS
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作者 韩丕功 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期533-544,共12页
This paper deals with the existence of solutions to the elliptic equation-△u-μ/|x|2=λu +|u|2*-2u + f(x,u) in Ω,u = 0 on (?)Ω, where Ω is a bounded domain in RN(N≥3), 0 ∈ Ω 2*=2N/N-2,λ> 0, λ (?) σμ,σμ... This paper deals with the existence of solutions to the elliptic equation-△u-μ/|x|2=λu +|u|2*-2u + f(x,u) in Ω,u = 0 on (?)Ω, where Ω is a bounded domain in RN(N≥3), 0 ∈ Ω 2*=2N/N-2,λ> 0, λ (?) σμ,σμ is the spectrum of the operator -△-μI/|x|2 with zero Dirichlet boundary condition, 0 <μ< μ-,μ-=(N-2)2/4, f(x,u)is an asymmetric lower order perturbation of |u|2* -1 at infinity. Using the dual variational methods, the existence of nontrivial solutions is proved. 展开更多
关键词 Semilinear elliptic equation dual variational functional critical point asymmetric nonlinearity
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