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Attention is drawn to dispersion relation techniques which are useful in calculating binding energies of light nuclei, mechanical form factors of particles and nuclei, and mean mass radii.Presented at the International Conference on Gravitation and Relativity, Copenhagen, July 1971.  相似文献   

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With the use of the Newman-Penrose spin coefficients, the radial part of the electrom equation in the de Sitter-Schwarzschild space is separated, and the transmission coefficient is calculated when the metric is specialized to the de Sitter case. Two different solutions of the radial equation are given. In the first one, the wavenumber corresponds to the flat space value; i.e., k2 = ω2 ? m2, where ω is the energy and m is the rest mass of the particle. In this case, when ω ? m, the transmission coefficient Γ becomes zero whereas, when ωm, it is finite and is zero only for the lowest angular momentum state (l = 12). In the second solution, k2 is found to involve the angular momentum. Γ in this case, exhibits a resonance phenomenon and becomes zero only for certain values of the energy or of the mass; one instance when Γ becomes zero is when ωm, l = 12 and k2 = m24. When m = 0, both expressions for Γ correspond to the value for the massless neutrino.  相似文献   

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We present the coherent states of a scalar massive particle on 1+3-de Sitter space. These states are vectors in Hilbert space, and they are labeled by points in the associated phase space. To do this, we use the fact that the phase space of a scalar massive particle on 1+3-de Sitter space is a cotangent bundle “T ?(S 3)” which is isomorphic with the complex sphere “ $S_{\mathbb{C}}^{3}We present the performances of a 330?g zinc molybdate (ZnMoO4) crystal working as scintillating bolometer as a possible candidate for a next generation experiment to search for neutrinoless double beta decay of 100Mo. The energy resolution, evaluated at the 2615?keV ??-line of 208Tl, is 6.3?keV FWHM. The internal radioactive contaminations of the ZnMoO4 were evaluated as <6???Bq/kg (228Th) and 27±6???Bq/kg (226Ra). We also present the results of the ?? vs ??/?? discrimination, obtained through the scintillation light as well as through the study of the shape of the thermal signal alone.  相似文献   

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If we study the de Sitter universe with the methods of projective geometry, we obtain a new mechanics valid on a cosmic scale and for hyperdense matter. In this projective mechanics the mass varies with the space-time distance, and the linear and angular momentum are reunited in a single projective tensor.  相似文献   

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We discuss the quantum phase transition that separates a vacuum state with fully gapped fermion spectrum from a vacuum state with topologically protected Fermi points (gap nodes). In the context of condensed-matter physics, such a quantum phase transition with Fermi point splitting may occur for a system of ultracold fermionic atoms in the region of BEC-BCS crossover, provided Cooper pairing occurs in the non-s-wave channel. For elementary particle physics, the splitting of Fermi points may lead to CPT violation, neutrino oscillations, and other phenomena.  相似文献   

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The authors empirically based contention that there exists an integral mass system for the principal baryons and the electron is put into a theoretical framework. This framework predicts a neutrally charged lepton which must correspond to the neutrino, generates very accurate base masses for the major leptons, mesons, and baryons and extremely accurate mass splitting for the principal octet of baryons. In addition, it predicts a totally new class of super heavy particles the lightest of which would have a mass greater than 38 GeV.  相似文献   

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From the definition of spinors as the minimal left (right) modules of multivectors (that is, of vectors and their outer products), we can construct a unified mathematical approach for the study of matter and its interaction fields, which are either defined as fields in the geometrical spacetime or considered as generators of the physical spacetime. It is also shown how matter and interaction fields can be represented either by spinor fields or by multivector fields, both types of fields carrying the same information as the traditional corresponding spinors, vectors, or tensors. Geometry is more transparent in one representation (multivector form), and physics is more obvious in the spinor representation. Our theory provides a unified and totally self-consistent representation of quarks (barions), leptons, and all their known interactions.  相似文献   

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Using a general classification of dark enegy models in four classes, we discuss the complementarity of cosmological observations to tackle down the physics beyond the acceleration of our universe. We discuss the tests distinguishing the four classes and then focus on the dynamics of the perturbations in the Newtonian regime. We also exhibit explicitely models that have identical predictions for a subset of observations.  相似文献   

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Starting with the 1975 discovery of the tau lepton, I look back on the last three decades of change in the substance and style of experimental and theoretical research in elementary particle physics. I recount the major accomplishments of those decades and predict a bright future for particle physics in the next two decades. Turning to three problems, I lament the change in theoretical style and taste, I discuss the growth in the complexity, size, and cost of particle physics experiments, and I conclude with a pessimistic comment on the size of particle physics collaborations.  相似文献   

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Some simple models of elementary particles are discussed; they may be described as semiclassical, quark, shell models. Particles are assumed to be composed of spherical concentric charged shells. Three basic types of shell are allowed, quantum numbers are associated with each type such as to establish a quantum number correspondence between the shell types and the (p, n, ) quarks. Particles are identified through the quantum numbers of their constituent shells (quarks).The basic assumptions underlying the models considered are relationships between the electromagnetic energy associated with elementary particles (quark systems) and particle masses. The electromagnetic energy is represented classically; the models are semiclassical in that the shell radii are related to particle Compton wavelengths.Particle mass and magnetic moment formulas are derived, possible values for quark masses are suggested, and possible connections of the models considered with particle symmetry schemes are discussed.  相似文献   

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The study of high energy cosmic rays is a diversified field of observational and phenomenological physics addressing questions ranging from shock acceleration of charged particles in various astrophysical objects, via transport properties through galactic and extragalactic space, to questions of dark matter, and even to those of particle physics beyond the Standard Model including processes taking place in the earliest moments of our Universe. After decades of mostly independent evolution of nuclear, particle and high energy cosmic ray physics we find ourselves entering a symbiotic era of these fields of research. Some examples of interrelations will be given from the perspective of modern Particle-Astrophysics and new major experiments will briefly be sketched.  相似文献   

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A unified treatment of conservation laws in general relativity, gauge theories, and elementary particle physics is formulated in the setting of principal fiber bundles. The group AUT(P) is introduced as the general gauge transformation group that covers space-time coordinate transformations. A set of master equations is exhibited for any Lagrangian density generally covariant with respect to AUT(P). The symmetry group for elementary particle theory is shown to be the structure group of the bundle only in the special case when the gauge potential is flat and the space-time is simply connected. In the general case, the symmetry group is reduced to the symmetry group of the gauge potential. This natural mechanism for a reduction of the symmetry group is speculated on as a model for spontaneous symmetry breaking.This essay received an honorable mention from the Gravity Research Foundation for the year 1981-Ed.Partially supported by a grant from the National Science Foundation.  相似文献   

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We argue that models in which an observable variation of the fine structure constant is explained by motion of a cosmic scalar field are not stable under renormalization and require massive fine-tuning that cannot be explained by any known mechanism.  相似文献   

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P C Vaidya  L K Patel 《Pramana》1989,32(6):731-739
A generalized Kerr-NUT type metric is considered in connection with Einstein field equations corresponding to perfect fluid plus a pure radiation field. A general scheme for obtaining the exact solutions of these field equations is developed. Two physically meaningful particular cases are investigated in detail. One gives the field of a radiating Kerr particle embedded in the Einstein universe. The other solution may probably represent a deSitter-like universe pervaded by a pure radiation field.  相似文献   

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A dynamical strongly interacting particle theory is presented. The theory explicitly exhibits the structures of particle states and provides intriguing insights into their working mechanisms. Agreement of the results with the experimental observations is excellent.  相似文献   

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