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Elementary Fermions: Strings, Planck Constant, Preons and Hypergluons
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期82-100,共19页
Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism ... Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism which is proportional to Planck’s constant. This may be the result of two massless bosons (hypergluons) coupled by a preon (prequark) exchange. It also gives a physical explanation to the origin of the Planck constant, and origin of spin. 展开更多
关键词 FERMIONS Preons Hypergluons strings Real Fields Planck Constant INTERFERENCE SPIN
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Stringy Phenomenology with Preon Models
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期1-7,共7页
We compare, following Pati, global symmetries, our topological supersymmetric preon model with the heterotic E<sub>8</sub> × E<sub>8</sub> string theory. We include Pati’s supergravity ba... We compare, following Pati, global symmetries, our topological supersymmetric preon model with the heterotic E<sub>8</sub> × E<sub>8</sub> string theory. We include Pati’s supergravity based preon model in this work and compare the preon interactions of his model to ours. Based on preon-string symmetry comparison and preon phenomenological results, we conclude that the fundamental particles are likely preons rather than standard model particles. . 展开更多
关键词 Topological Field Theory Chern-Simons Theory SUPERSYMMETRY string Theory
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Towards 6D Little String Theory of Particles
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期546-561,共16页
A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predicti... A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predictions are discussed. 展开更多
关键词 Standard Model Composite Models SUPERSYMMETRY Little string Theory T-DUALITY HOLOGRAPHY
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Detachable string magnetically controlled capsule endoscopy for the noninvasive diagnosis of esophageal diseases:A prospective,blind clinical study
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作者 Yan-Ling Yang Huang-Wen Qin +5 位作者 Zhao-Yu Chen Hui-Ning Fan Yi Yu Wei Da Jin-Shui Zhu Jing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1121-1131,共11页
BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in patients.In contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being ... BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in patients.In contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being applied for the detection of stomach and small intestinal diseases,but its application in treating esophageal diseases is not widespread.AIM To evaluate the safety and efficacy of detachable string MCE(ds-MCE)for the diagnosis of esophageal diseases.METHODS Fifty patients who had been diagnosed with esophageal diseases were pros-pectively recruited for this clinical study and underwent ds-MCE and conven-tional EGD.The primary endpoints included the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for patients with esophageal diseases.The secondary endpoints consisted of visualizing the esophageal and dentate lines,as well as the subjects'tolerance of the procedure.RESULTS Using EGD as the gold standard,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for esophageal disease detection were 85.71%,86.21%,81.82%,89.29%,and 86%,respectively.ds-MCE was more comfortable and convenient than EGD was,with 80%of patients feeling that ds-MCE examination was very comfortable or comfortable and 50%of patients believing that detachable string v examination was very convenient.CONCLUSION This study revealed that ds-MCE has the same diagnostic effects as traditional EGD for esophageal diseases and is more comfortable and convenient than EGD,providing a novel noninvasive method for treating esophageal diseases. 展开更多
关键词 Clinical trial Detachable string magnetically controlled capsule endoscopy ESOPHAGOGASTRODUODENOSCOPY Noninvasive diagnosis Esophageal diseases
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Function of note strings in Japanese Tit alarm calls to the Common Cuckoo:a playback experiment 被引量:10
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作者 Jiangping Yu Weiwei Lv +5 位作者 Hongwei Xu Nehafta Bibi Yangyang Yu Yunlei Jiang Wei Liang Haitao Wang 《Avian Research》 CSCD 2017年第3期141-146,共6页
Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Jap... Background: Birds produce alarm calls to convey information about threats. Some Passerine alarm calls consist of several note strings, but few studies have examined their function. Previous studies have shown that Japanese Tits(Parus minor) can alter the calling rate and number and combination of notes in response to predators. We previously found the combinations of note types in Japanese Tit alarm calls to be significantly different in response to the Sparrowhawk(Accipiter nisus) and Common Cuckoo(Cuculus canorus).Methods: Through playback experiments, we tested whether the note strings in Japanese Tit alarm calls to the Common Cuckoo have different functions in conveying information. The note strings of selected alarm calls were divided into the categories of C and D, and different calls were then constructed separately based on the two note string categories. Original alarm calls(C–D), C calls and D calls were played back to male Japanese Tits during the incubation period.Results: Male Japanese Tits had a significantly stronger response to C calls than to C–D calls, and they showed a significantly stronger response to both C and C–D calls than to D calls, suggesting that Japanese Tits discriminated between the C and D calls.Conclusions: Our study demonstrated that the C-and D-category note strings of Japanese Tit alarm calls to the Common Cuckoo have different functions, which supports the previous finding that different note strings in an alarm call can provide different information to receivers. However, the exact meanings of these note strings are not yet known, and further investigation is therefore required. 展开更多
关键词 Alarm call Male Japanese Tit Note strings FUNCTION Brood parasitism PLAYBACK
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ITERATIVE ALGORITHM FOR AXIALLY ACCELERATING STRINGS WITH INTEGRAL CONSTITUTIVE LAW 被引量:2
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作者 Weijia Zhao Liqun Chen 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第5期449-456,共8页
A numerical method is proposed to simulate the transverse vibrations of a viscoelastic moving string constituted by an integral law. In the numerical computation, the Galerkin method based on the Hermite functions is ... A numerical method is proposed to simulate the transverse vibrations of a viscoelastic moving string constituted by an integral law. In the numerical computation, the Galerkin method based on the Hermite functions is applied to discretize the state variables, and the Runge- Kutta method is applied to solve the resulting differential-integral equation system. A linear iterative process is designed to compute the integral terms at each time step, which makes the numerical method more efficient and accurate. As examples, nonlinear parametric vibrations of an axially moving viscoelastic string are analyzed. 展开更多
关键词 iterative algorithm partial-differential-integral equation Hermite function Galerkin method axially moving string integral constitutive law
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Eigenvalue and stability analysis for transverse vibrations of axially moving strings based on Hamiltonian dynamics 被引量:4
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作者 Yuefang Wang Lihua Huang Xuetao Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期485-494,共10页
The Hamiltonian dynamics is adopted to solve the eigenvalue problem for transverse vibrations of axially moving strings. With the explicit Hamiltonian function the canonical equation of the free vibration is derived. ... The Hamiltonian dynamics is adopted to solve the eigenvalue problem for transverse vibrations of axially moving strings. With the explicit Hamiltonian function the canonical equation of the free vibration is derived. Non-singular modal functions are obtained through a linear, symplectic eigenvalue analysis, and the symplectic-type orthogonality conditions of modes are derived. Stability of the transverse motion is examined by means of analyzing the eigenvalues and their bifurcation, especially for strings transporting with the critical speed. It is pointed out that the motion of the string does not possess divergence instability at the critical speed due to the weak interaction between eigenvalue pairs. The expansion theorem is applied with the non-singular modal functions to solve the displacement response to free and forced vibrations. It is demonstrated that the modal functions can be used as the base functions for solving linear and nonlinear vibration problems. 展开更多
关键词 Axially moving strings . Symplectic . Modalanalysis . Stability . Divergence
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ON GALERKIN DISCRETIZATION OF AXIALLY MOVING NONLINEAR STRINGS 被引量:1
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作者 Liqun Chen Weijia Zhao Hu Ding 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第4期369-376,共8页
A computational technique is proposed for the Galerkin discretization of axially moving strings with geometric nonlinearity. The Galerkin discretization is based on the eigenfunctions of stationary strings. The discre... A computational technique is proposed for the Galerkin discretization of axially moving strings with geometric nonlinearity. The Galerkin discretization is based on the eigenfunctions of stationary strings. The discretized equations are simplified by regrouping nonlinear terms to reduce the computation work. The scheme can be easily implemented in the practical programming. Numerical results show the effectiveness of the technique. The results also highlight the feature of Galerkin's discretization of gyroscopic continua that the term number in Galerkin's discretization should be even. The technique is generalized from elastic strings to viscoelastic strings. 展开更多
关键词 Galerkin discretization partial differential equation NONLINEARITY transverse vibration axially moving string VISCOELASTICITY
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A Foundation for Lorentz Force Based on Vibrating Strings as a Compact Fluid 被引量:1
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作者 Narahari V. Joshi 《World Journal of Mechanics》 2014年第8期247-250,共4页
Several aspects related with Lorentz force are discussed in the light of the presence of vibrating strings. Strings are considered as a compact,?tension and viscosity-free incompressible liquid. The motion of a charge... Several aspects related with Lorentz force are discussed in the light of the presence of vibrating strings. Strings are considered as a compact,?tension and viscosity-free incompressible liquid. The motion of a charge particle, obviously, represents the “line of vortex” in the medium of fluid. The term (VXB) turns out to be the natural consequence of Vortex dynamics. The present investigation also reveals the nature of the magnetic field and explains why and how this additional term takes part in Lorentz force. 展开更多
关键词 LORENTZ FORCE ORIGIN for Magnetic Field FLUID Dynamics string Theory
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Critical Buckling of Drill Strings in Cylindrical Cavities of Inclined Bore-Holes 被引量:1
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作者 Nabil Musa Valery Gulyayev +1 位作者 Nataliya Shlyun Hasan Aldabas 《Journal of Mechanics Engineering and Automation》 2016年第1期25-38,共14页
Notwithstanding the fact that the problem of drill string buckling (Eulerian instability) inside the cylindrical cavity of an inclined bore-hole attracts attention of many specialists, it is far from completion. Thi... Notwithstanding the fact that the problem of drill string buckling (Eulerian instability) inside the cylindrical cavity of an inclined bore-hole attracts attention of many specialists, it is far from completion. This peculiarity can be explained by the complexity of its mathematic model which is described by singularly perturbed equations. Their solutions (eigen modes) have the shapes of boundary effects or buckles (harmonic wavelets) localized in zones of the bore-hole that are not specified in advance. Therefore, the problem should be stated in the domain of entire length of the drill string or in some separated part including an expected zone of its buckling. In the paper, a mathematic model for computer analysis of incipient buckling of a drill string in cylindrical channel of an inclined bore-hole is elaborated. The constitutive equation is deduced with allowance made for action of gravity, contact, and friction forces. Computer simulation of the drill string buckling is performed for different values of the bore-hole inclination angle, its length, friction coefficient, and clearance. The eigen values (critical loads) are found and modes of stability loss are constructed. The numerical results for the case when the inclination angle equals friction angle coincide with ones obtained analytically. 展开更多
关键词 Deep drilling inclined bore-holes drill strings stability singularly perturbed problem.
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NEW METHOD FOR GEOMETRIC NONLINEAR ANALYSIS OF LARGE DISPLACEMENT DRILL STRINGS
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作者 谈梅兰 王鑫伟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第7期921-928,共8页
Based on the actual measured well depth, azimuth and oblique angles, a novel interpolation method to obtain the well axis is developed. The initial stress of drill string at the reference state consistent with well ax... Based on the actual measured well depth, azimuth and oblique angles, a novel interpolation method to obtain the well axis is developed. The initial stress of drill string at the reference state consistent with well axis can be obtained from the curvature and the tortuosity of well axis. By using the principle of virtual work, the formula to compute the equivalent load vector of the initial stress was derived. In the derivation,the natural (curvilinear) coordinate system was adopted since both the curvature and the tortuosity were generally not zero. A set of displacement functions fully reflecting the rigid body modes was used. Some basic concepts in the finite element analysis of drill string were clarified. It is hoped that the proposed method would offer a theoretical basis for handling the geometric nonlinear problem of the drill string in a 3-D larg edisplacement wellbore. 展开更多
关键词 finite element geometric nonlinearity numerical simulation drill string
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Resistance Measurements and Interpretations Relating to Flashover of Artificially Contaminated Ceramic Insulator Strings
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作者 B.SubbaReddy G.R.Nagabhushana 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第6期2093-2100,共8页
The flashover of insulator strings occurring at normal working voltages undercontaminated/polluted conditions, obviously deserves serious consideration. Though much researchhas been gone into pollution-induced flashov... The flashover of insulator strings occurring at normal working voltages undercontaminated/polluted conditions, obviously deserves serious consideration. Though much researchhas been gone into pollution-induced flashover phenomena but grey areas still exist in ourknowledge. In the present experimental study the breakdown (flashover) voltages across gaps oninsulator top surfaces and gaps between sheds (on the underside of an insulator), also the flashoverstudies on a single unit and a 3-unit insulator strings were carried out. An attempt has been madeto correlate the values obtained for all the cases. From the present investigation it was found thatresistance measurement of individual units of a polluted 3-unit string before and after flashoverindicates that strongly differing resistances could be the cause of flashover of ceramic discinsulator strings. 展开更多
关键词 artificially contaminated/polluted insulator strings resistancemeasurements insulator flashover breakdown voltages ceramic insulators
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Rotating Classical Strings
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作者 Martin Tamm 《Journal of Modern Physics》 2017年第5期761-769,共9页
It is a starting point in string theory to assume that elementary particles are in fact rotating strings, and the final goal of the theory is a complete description of fundamental physics, including general relativity... It is a starting point in string theory to assume that elementary particles are in fact rotating strings, and the final goal of the theory is a complete description of fundamental physics, including general relativity. This paper is instead concerned with the reversed question: starting from general relativity, is there a good way to motivate why rotating strings should be more natural models for elementary particles than, say, spherical particles or point-particles? Also, the purpose here is not to motivate full string theory. For example, no hidden dimensions come into play, only the four usual ones, and strings are defined in a very simple geometric way. Rather, the focus is on investigating an interesting mathematical property, which implies that strings may have special features with respect to rotation which spherically symmetric particles have not. In particular, it turns out that in a certain sense rotating strings are simpler than non-rotating ones. This is a consequence of the indefinite metric, and the main result states that the curvature of a non-rotating string, as measured by the square of the scalar curvature, may be reduced by letting it rotate in an appropriate way. The calculations underlying this theorem are heavy and have partly been car-ried out using Mathematica, although in principle the essential theorem may not require super-human labour. 展开更多
关键词 General RELATIVITY string Theory ROTATION CURVATURE
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Alignment of Quasar Polarizations on Large Scales Explained by Warped Cosmic Strings. PART II: The Second Order Contribution
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作者 Reinoud Jan Slagter 《Journal of Modern Physics》 2017年第2期163-180,共18页
We find an azimuthal-angle dependent approximate wave like solution to second order on a warped five-dimensional manifold with a self-gravitating U(1) scalar gauge field (cosmic string) on the brane using the multiple... We find an azimuthal-angle dependent approximate wave like solution to second order on a warped five-dimensional manifold with a self-gravitating U(1) scalar gauge field (cosmic string) on the brane using the multiple-scale method. The spectrum of the several orders of approximation show maxima of the energy distribution dependent on the azimuthal-angle and the winding numbers n of the subsequent orders of scalar field. This breakup of the quantized flux quanta does not lead to instability of the asymptotic wavelike solution, due to the suppression of the n-dependency in the energy mo-mentum tensor components by the warp factor. This effect is triggered by the contribution of the five dimensional Weyl tensor on the brane. This con-tribution can be understood as dark energy and can trigger the self-acceleration of the universe without the need of a cosmological constant. There is a striking relation between the symmetry breaking of the Higgs field described by the winding number and the SO(2) breaking of the axially symmetric configuration into a discrete subgroup of rotations about 180&deg;. The discrete sequence of non-axially symmetric deviations, cancelled by the emission of gravitational waves in order to restore the SO(2) symmetry, triggers the pressure Tzz for discrete values of the azimuthal-angle. There can be a possible relation between the recently discovered angle-preferences of polarization axes of quasars on large scales and our theoretical predicted angle-dependency and can be an evidence for the existence of cosmic strings. The discovery of the increase of polarization rate in smaller subgroups of the several large-quasar groups (LQGs), the red shift dependency and the relative orientation of the spin axes with respect to the major axes of their host LQGs, point at a fractional azimuthal structure, were also found in our cosmic string model. This peculiar discontinuous large scale structure, i.e., polarizations directions of multiples of, for example, &pi;/2 or&pi;/4, can be explained by the spectrum of azimuthal-angle dependent wavelike modes without the need of conventional density perturbations in standard 4D cosmological models. Carefully com-parison of the spectrum of extremal values of the first and second order &phi;-dependency and the distribution of the alignment of the quasar polarizations is necessary. This can be accomplished when more observational data become available. 展开更多
关键词 QUASAR Polarization COSMIC strings Warped BRANE World Models U(1) Scalar-Gauge Field Multiple-Scale Analysis
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Planck’s Constant—A Result of Two Strings Coupling
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2022年第4期919-926,共8页
The existence of strings has not yet been proven, but if a fermion is considered as being made up of two coupled strings, then the coupling between these two strings creates tension in the strings, and this tension is... The existence of strings has not yet been proven, but if a fermion is considered as being made up of two coupled strings, then the coupling between these two strings creates tension in the strings, and this tension is proportional to the coupling force via the Planck constant. This provides an explanation for the origin of the Planck constant. 展开更多
关键词 Planck Constant strings Coupling Interaction
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Anisotropic massive strings in the scalar-tensor theory of gravitation
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作者 Anil Kumar Yadav 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第7期772-782,共11页
We present the model of an anisotropic universe with string fluid as the source of matter within the framework of the scalar-tensor theory of gravitation. An exact solution of field equations is obtained by applying B... We present the model of an anisotropic universe with string fluid as the source of matter within the framework of the scalar-tensor theory of gravitation. An exact solution of field equations is obtained by applying Berman's law of variation to Hubble's parameter which yields a constant value of the deceleration parameter. The nature of classical potential is examined for the model under consideration. It has also been found that the massive strings dominate in the early universe and finally disap-pear from the universe. This is in agreement with current astronomical observations. The physical and dynamical properties of the model are also discussed. 展开更多
关键词 early universe -- massive strings -- scalar-tensor theory -- classicalpotential
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A Note on q-Deformed Two-Dimensional Yang-Mills and Open Topological Strings
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作者 张鹏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期317-322,共6页
In this note we make a test of the open topological string version of the OSV conjecture in the toric Calabi-Yau manifold X = O(-3) → P^2 with background D4-branes wrapped on Lagrangian submanifolds. The Dbrahe par... In this note we make a test of the open topological string version of the OSV conjecture in the toric Calabi-Yau manifold X = O(-3) → P^2 with background D4-branes wrapped on Lagrangian submanifolds. The Dbrahe partition function reduces to an expectation value of some inserted operators of a q-deformed Yang Mills theory living on a chain of P^1 's in the base p2 of X. At large N this partition function can be written as a sum over squares of chiral blocks, which are related to the open topological string amplitudes in the local p2 geometry with branes at both the outer and inner edges of the toric diagram. This is in agreement with the conjecture. 展开更多
关键词 topological string theory 2d Yang-Mills theory OSV conjecture
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A Remark on General Solution for Motion of Relativistic Strings in Minkowski Space ■^(1+n)
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作者 WANG Zeng-Gui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期914-918,共5页
This note concerns the motion of relativistic strings in the Minkowski space R^(1+n).We rederive the generalsolution formula in closed form for the equation for the motion of relativistic string.Our method is differen... This note concerns the motion of relativistic strings in the Minkowski space R^(1+n).We rederive the generalsolution formula in closed form for the equation for the motion of relativistic string.Our method is different completelyfrom others. 展开更多
关键词 SPACE-TIME the equations for the motion of relativistic string general solution formula
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The Oceanic Imagination: Affects, Surreal Images and Strings
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作者 Emily ShuHui Tsai 《Cultural and Religious Studies》 2019年第7期348-359,共12页
The creative forces of affects are considered to be a mysterious power within our immanence. Although creators exist like lonely islands and may be more vulnerable to poor health, it is problematic to draw an inferenc... The creative forces of affects are considered to be a mysterious power within our immanence. Although creators exist like lonely islands and may be more vulnerable to poor health, it is problematic to draw an inference that mental illness nourishes creativity. Artists, philosophers, and scientists have to struggle with chaos to create a new vision into their works. This paper argues that first, the creativity of affects is a mysterious power of our immanence, not nourished by pathology;second, the surreal images of curved and juxtaposed spaces by the artists resonate with the scientific experiments conducted by string physicists who propose the existence of multiverse with the possibility of 11-dimensional spaces. Therefore, the creators have shared the equally-important status as the singular beings in their different modes of lives. Deleuze’s and Guattari’s creative concepts of philosophy help improve the better understanding of the mysterious power of oceanic affects within our immanence. Thus, the general opinion that creativity and mental illness are infamously connected should be entirely re-questioned and re-examined. 展开更多
关键词 CREATIVITY chaos affect surreal images string IMAGINATION
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Pipa: Ancient Tunes on Emotionally Charged Strings
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作者 MENG JIAXIN 《China Today》 2021年第3期78-80,共3页
THE quote in the left is an extract taken from the Song of the Pipa,a classic poem written in the year 816 by the well-known Chinese poet Bai Juyi.One day when travelling down the Yangtze River on a boat,he suddenly h... THE quote in the left is an extract taken from the Song of the Pipa,a classic poem written in the year 816 by the well-known Chinese poet Bai Juyi.One day when travelling down the Yangtze River on a boat,he suddenly heard a captivating pipa melody wafting from afar.Greatly moved,Bai tried to trace the origin of the music and then found the pipa player,who had been a court pipa player when she was young.Putting on a soul-stirring pipa performance,the player seemingly intended to tell all of her joy in her prime and haplessness in the mid-life,which struck a chord with the poet who was then undergoing his own struggles.Greatly inspired,Bai penned the Song of the Pipa,which is now recognized as a masterpiece poem.The few lines from this poem provide an elaborate and vivid description of the abundant timbre of the pipa,a four-stringed Chinese musical instrument. 展开更多
关键词 string STIRRING suddenly
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