摘要:

The design of a successful concert hall continues to be a difficult task. But recent applications of computer model studies combined with new methods of quantifying personal preference and subjective quality promise to make “the acoustics” of future halls more predictable and satisfactory.

ISSN:0002-9505    

DOI:10.1119/1.1987272

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

The basic ideas of the quark model are explained in a manner that should make the presentation clear to students who have completed a course in undergraduate quantum mechanics. Some simple calculations which can be performed by advanced undergraduate students with appropriate guidance from an instructor are presented.

ISSN:0002-9505    

DOI:10.1119/1.1987273

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

The self-consistent, independent-particle Hartree equations for N fermions interacting with a separable (in configuration space) two-body potential are solved exactly in one and three dimensions. The exclusion principle is accounted for by allowing only one particle per orbital state. The possibility of only a finite number of particles being bound self-consistently, for given two-body force parameters, is studied and the effect of introducing the observed (in real nuclei) approximate constancy with particle number of particle density and common well depth is also considered.

ISSN:0002-9505    

DOI:10.1119/1.1987274

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

Necessary and sufficient conditions for the construction of the character table of a finite group from its multiplication table are discussed. It is pointed out that the technique most commonly used to evaluate the characters is inadequate. A rigorous method is described and its utility is discussed.

ISSN:0002-9505    

DOI:10.1119/1.1987275

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

A simple instructive demonstration of the Brattsev-Epstein theorem is presented. The theorem can be verified rigorously for the ground state energies of a coupled oscillator calculated exactly and in the adiabatic approximation.

ISSN:0002-9505    

DOI:10.1119/1.1987276

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

A complete asymptotic expansion, in inverse powers of the distance, for the scattered wave function solution to Schrödinger's equation with a short-range potential is derived by two simple arguments. The result is identical to a more rigorous calculation by Buslaev. The difference between the asymptotic series and the exact wave function vanishes at infinity faster than any negative power of the distance. Explicit formulas for the coefficients are derived and their physical significance discussed. The application to the uniqueness theorem for the Schrödinger equation is also discussed.

ISSN:0002-9505    

DOI:10.1119/1.1987277

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

Interaction problems in classical relativistic electro-dynamics are frustratingly difficult to solve, since the differential equation of motion involves functions of both the present and retarded times. In this paper the author eliminates the retarded functions from the equation of motion for the two-body problem in which two equal masses with opposite charges that are equal in magnitude are released from rest and allowed to fall into one another. In the final form of the equation of motion only the present time, the present position, and derivatives of the present position with respect to the present time appear—in other words, it is an equation with one unknown and the present time only. To accomplish this simplification of the equation of motion, the author employs the Lorentz condition,∇·A+δΦ/cδt=0,and the expressionE=−∇Φ−δA/cδtto obtain a partial differential equation in the retarded separation distance R that can be solved. When the resulting relationships are substituted into the Lorentz force equation it contains only functions of the present time.

ISSN:0002-9505    

DOI:10.1119/1.1987278

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

The traditional resolution of Gibbs paradox seems to give rise to a further paradox. A resolution of this paradox is proposed.

ISSN:0002-9505    

DOI:10.1119/1.1987279

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

The energies and wavefunctions of an electron in a one-dimensional crystal are obtained for two Kronig-Penney models directly from the T matrix. The problems serve as good examples of the T-matrix method and indicate the usefulness of this approach in studying the behavior of electrons in crystals.

ISSN:0002-9505    

DOI:10.1119/1.1987280

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP

摘要:

We first consider the partial differential equation that governs one-dimensional heat flow in a homogeneous medium. This equation is reduced to a difference equation, and the problem of difference equation stability and convergence is discussed and examples of the breakdown of each are given. Next, the above analysis is extended to a three-dimensional space with spherical symmetry. Several interesting problems are programmed and the solutions are displayed in graphical form. The accuracy of the numerical difference technique is checked by comparison with exact Fourier series solutions. The paper is mainly intended for beginning students of physics and engineering, and also for college teachers who have not had a formal course in numerical solutions of partial differential equations.

ISSN:0002-9505    

DOI:10.1119/1.1987281

出版商:American Association of Physics Teachers    

年代:1973

数据来源: AIP