期刊文献+
共找到8篇文章
< 1 >
每页显示 20 50 100
Lie symmetry group transformation for MHD natural convection flow of nanofluid over linearly porous stretching sheet in presence of thermal stratification 被引量:2
1
作者 A.B.ROSMILA R.KANDASAMY I.MUHAIMIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期593-604,共12页
The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The pa... The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The partial differential equations governing the problem under consideration are transformed by a special form of the Lie symmetry group transformations, i.e., a one-parameter group of transformations into a system of ordinary differential equations which are numerically solved using the Runge-Kutta-Gill- based shooting method. It is concluded that the flow field, temperature, and nanoparticle volume fraction profiles are significantly influenced by the thermal stratification and the magnetic field. 展开更多
关键词 lie symmetry group transformation NANOFLUID porous medium thermalstratification magnetic field
下载PDF
Lie Symmetry Groups of(2+1)-Dimensional BKP Equation and Its New Solutions 被引量:1
2
作者 MA Hong-Cai LOU Sen-Yue DENG Ai-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期685-688,共4页
A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physicssystems.Applying the modified direct method to the well-known (2+1)-dimensional BKP equation we get its symmetry.Fu... A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physicssystems.Applying the modified direct method to the well-known (2+1)-dimensional BKP equation we get its symmetry.Furthermore,the exact solutions of (2+1)-dimensional BKP equation are obtained through symmetry analysis. 展开更多
关键词 (2+1)-dimensional BKP equation lie symmetry group CK's direct method exact solution
下载PDF
Einstein’s Dark Energy via Similarity Equivalence, ‘tHooft Dimensional Regularization and Lie Symmetry Groups 被引量:4
3
作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第1期56-81,共26页
Realizing the physical reality of ‘tHooft’s self similar and dimensionaly regularized fractal-like spacetime as well as being inspired by a note worthy anecdote involving the great mathematician of Alexandria, Pytha... Realizing the physical reality of ‘tHooft’s self similar and dimensionaly regularized fractal-like spacetime as well as being inspired by a note worthy anecdote involving the great mathematician of Alexandria, Pythagoras and the larger than life man of theoretical physics Einstein, we utilize some deep mathematical connections between equivalence classes of equivalence relations and E-infinity theory quotient space. We started from the basic principles of self similarity which came to prominence in science with the advent of the modern theory of nonlinear dynamical systems, deterministic chaos and fractals. This fundamental logico-mathematical thread related to partially ordered sets is then applied to show how the classical Newton’s kinetic energy E = 1/2mv<sup>2</sup> leads to Einstein’s celebrated maximal energy equation E = mc<sup>2</sup> and how in turn this can be dissected into the ordinary energy density E(O) = mc<sup>2</sup>/22 and the dark energy density E(D) = mc<sup>2</sup>(21/22) of the cosmos where m is the mass;v is the velocity and c is the speed of light. The important role of the exceptional Lie symmetry groups and ‘tHooft-Veltman-Wilson dimensional regularization in fractal spacetime played in the above is also highlighted. The author hopes that the unusual character of the analysis and presentation of the present work may be taken in a positive vein as seriously attempting to propose a different and new way of doing theoretical physics by treating number theory, set theory, group theory, experimental physics as well as conventional theoretical physics on the same footing and letting all these diverse tools lead us to the answer of fundamental questions without fear of being labelled in one way or another. 展开更多
关键词 Equivalence Relation SCALING Intermediate Asymptotic Golden Mean Scaling Einstein Self Similarity Fractal Scaling E-INFINITY Special Relativity Random Cantor Sets ‘tHooft Regularization Fractal Quantum Field Quantum Gravity Exceptional lie symmetry groups
下载PDF
Symmetry and Exact Solutions of (2+1)-Dimensional Generalized Sasa-Satsuma Equation via a Modified Direct Method
4
作者 LU Chang-Cheng CHEN Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期973-978,共6页
In this paper, first, we employ classic Lie symmetry groups approach to obtain the Lie symmetry groupsof the well-known (2+1)-dimensional Generalized Sasa-Satsuma (GSS) equation. Second, based on a modified directmeth... In this paper, first, we employ classic Lie symmetry groups approach to obtain the Lie symmetry groupsof the well-known (2+1)-dimensional Generalized Sasa-Satsuma (GSS) equation. Second, based on a modified directmethod proposed by Lou [J. Phys. A: Math. Gen. 38 (2005) L129], more general symmetry groups are obtained andthe relationship between the new solution and known solution is set up. At the same time, the Lie symmetry groupsobtained are only special cases of the more general symmetry groups. At last, some exact solutions of GSS equationsare constructed by the relationship obtained in the paper between the new solution and known solution. 展开更多
关键词 classic lie symmetry groups approach modified CK's direct method generalized Sasa-Satsuma equation
下载PDF
Quantum Dark Energy from the Hyperbolic Transfinite Cantorian Geometry of the Cosmos 被引量:1
5
作者 Mohamed S. El Naschie 《Natural Science》 2016年第3期152-159,共8页
The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-pa... The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-particle zero set as a core and a quantum pre-wave empty set as cobordism or surface of the core, we connect the interaction of two such self similar units to a compact four dimensional manifold and a corresponding holographic boundary akin to the compactified Klein modular curve with SL(2,7) symmetry. Based on this model in conjunction with a 4D compact hy- perbolic manifold M(4) and the associated general theory, the so obtained ordinary and dark en- ergy density of the cosmos is found to be in complete agreement with previous analysis as well as cosmic measurements and observations such as WMAP and Type 1a supernova. 展开更多
关键词 Dark Energy Accelerated Cosmic Expansion Hyperbolic Geometry Fractal Geometry Transfinite set Theory ‘tHooft Dimensional Regularization Hardy’s Quantum Entanglement Davis Hyperbolic Manifold Compactified Klein Modular Curve Fractal Counting lie symmetry groups Stein Spaces
下载PDF
From Witten’s 462 Supercharges of 5-D Branes in Eleven Dimensions to the 95.5 Percent Cosmic Dark Energy Density behind the Accelerated Expansion of the Universe 被引量:1
6
作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2016年第2期57-61,共5页
The measured 95.5% dark energy density of the cosmos presumed to be behind the observed accelerated cosmic expansion is determined theoretically based upon Witten’s five branes in eleven dimensions theory. We show th... The measured 95.5% dark energy density of the cosmos presumed to be behind the observed accelerated cosmic expansion is determined theoretically based upon Witten’s five branes in eleven dimensions theory. We show that the said dark energy density is easily found from the ratio of the 462 states of the five dimensional Branes to the total number of states, namely 528 minus the 44 degrees of freedom of the vacuum, i.e. , almost exactly as found in WMAP and Type 1a supernova measurements. 展开更多
关键词 Number Theory Witten Branes Dark Energy Superstrings Cosmic Expansion Type 1a Supernova E-INFINITY Exceptional lie symmetry groups
下载PDF
New Exact Solutions and Conservation Laws to (3+1)-Dimensional Potential-YTSF Equation 被引量:10
7
作者 ZHANG Li-Hua LIU Xi-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期487-492,共6页
Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-d... Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-dimensional potentiaial-YTSF equation. Baaed on the invariant group theory, Lie symmetries of the (3+1)-dimensional potential-YTSF equation are obtained. We equation with the given Lie symmetry. 展开更多
关键词 new exact solutions lie point symmetry groups conservation laws (3+1)-dimensional potential-YTSF equation
下载PDF
Explicit Soliton and Periodic Solutions to Three-Wave System with Quadratic and Cubic Nonlinearities
8
作者 林机 赵丽娜 李画眉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期676-680,共5页
Lie group theoretical method and the equation of the Jacobi elliptic function are used to study the three wave system that couples two fundamental frequency (FF) and a single second harmonic (SH) one by competing... Lie group theoretical method and the equation of the Jacobi elliptic function are used to study the three wave system that couples two fundamental frequency (FF) and a single second harmonic (SH) one by competing X^(2) (quadratic) and X^(3) (cubic) nonlinearities and birefringence. This system shares some of the nice properties of soliton system. On the phase-locked condition; we obtain large families of analytical solutions as the soliton, kink and periodic solutions of this system. 展开更多
关键词 optical soliton lie group symmetry competing nonlinearity
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部