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161.
We consider the ground state energy of a massive scalar field in the space-time of a thick cosmic string in the 2+1 dimensional case for arbitrary angle deficit by using the zeta-function approach. Final numerical calculations were made in the massless case, only. We show that the zero point energy is negative, and for small angle deficit it is proportional to the fourth degree of the deficit. 相似文献
162.
从严格的SUc(3)对称,分析qq+ng多部分子体系的色单态集,研究了各类色单态中部分子间的色弦组态.计算发现随n的增加,与Lund CD模型中性质对应的单态色弦几率迅速减少,而与胶子球性质相似的单态集团的比例急速增多,它与αs无关,直观表现为集体效应. 相似文献
163.
A. S. Alexandrov A. D. Mironov A. Yu. Morozov 《Theoretical and Mathematical Physics》2007,150(2):153-164
Small M-theories incorporate various models representing a unified family in the same way that the M-theory incorporates a
variety of superstring models. We consider this idea applied to the family of eigenvalue matrix models: their M-theory unifies
various branches of the Hermitian matrix model (including the Dijkgraaf-Vafa partition functions) with the Kontsevich τ-function.
Moreover, the corresponding duality relations are reminiscent of instanton and meron decompositions, familiar from the Yang-Mills
theory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 150, No. 2, pp. 179–192, February, 2007. 相似文献
164.
165.
Most lenses composed of spherical or aspherical surfaces have symmetrical focusing properties about an optical axis. On the other hand, unconventional optical systems such as cylindrical lenses, astigmatic or progressive power glasses have axially asymmetrical focusing properties. In this study, the method of measuring focusing properties by the moire technique is extended to asymmetrical lenses. Some unconventional lenses were experimentally tested, and the focusing power in the interesting region and azimuthal direction of the aperture was evaluated. 相似文献
166.
L. D. Soloviev 《Theoretical and Mathematical Physics》2003,136(3):1225-1250
We find all independent classical solutions for the three-mode Nambu–Goto string. We investigate the geometry of the closed curves obtained. Canonical quantization is performed for a part of the solutions obtained. We consider the spectrum of the quantum states obtained. It is consistent with the experimental masses and quantum numbers of mesons corresponding to glueballs. The leading Regge trajectory of the obtained states is consistent with the available data on the Pomeron trajectory.Deceased 相似文献
167.
A method for estimating the plucking point of guitar tones is proposed. The algorithm is based on investigating the time lag between two consecutive pulses arriving at the bridge of the guitar. The signal is detected with an under-saddle pickup attached to the bridge. The method determines the minimum of the autocorrelation function for one period of the signal. The time lag of the minimum can be converted into the distance from the bridge where the string was plucked. The results obtained with the method are good, the error remains smaller than one centimetre, except for a few outliers. The algorithm is easy to implement and can be used to analyse playing styles. The efficiency of the method gives the potential to also use it in real-time computer music applications. 相似文献
168.
Roman Kotecký Lahoussine Laanait Alain Messager Jean Ruiz 《Journal of statistical physics》1990,58(1-2):199-248
Theq-state Potts model (both scalar and gauge versions) is rewritten, with the help of the duality transformation, into a form of the Pirogov-Sinai theory with noninteracting contours that can be controlled by cluster expansions onceq is large enough. This is then used in a new proof of the existence of a unique transition (inverse) temperature
t
, where the mean internal energy is discontinuous. Moreover, we prove for the scalar model (again forq large enough) that there are discontinuities at
t
of the magnetization and of the mass gap, with the magnetization vanishing below
t
and the mass gap vanishing above
t
. We also show that the surface tensions between ordered stable phases are strictly positive up to
t
, and the surface tension between an ordered phase and the disordered one is strictly positive at
t
. For the three-dimensional gauge model, the Wilson parameter exhibits a direct transition from an area law decay (quark confinement) to a perimeter law decay (deconfinement).On leave from ENS Rabat, Morocco. 相似文献
169.
170.
Chiral ligand (A)‐N,N′‐Bis(2‐hydroxy‐3,5‐di‐tert‐butyl‐arylmethyl)‐1,1′‐binaphthalene‐2,2′‐diamine derived from the reduction of Schiff base (R)‐2,2′‐bis (3,5‐di‐tert‐butyl‐2‐hydroxybenzylideneamino)‐1, 1′‐binaphthyl with LiAlH4, is fairly effective in the asymmetric addition reaction of diethylzinc to aldehydes by which good yields (46%‐94%) of the corresponding sec‐alcohols can be obtained in moderate ee (51%‐79%) with R configuration for a variety of aldehydes. 相似文献