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1.
The results of new measurements of the optical constantsn andk of the alkali metalK, performed in ultrahigh vacuum on mirrorlike surfaces free of any contamination and distortion in the wavelength region from 0·365 μ to 2 μ at temperatures between ?183° C and +85° C permit to separate the absorption due to interband transitions (photoexcitation of valency electrons) from the “classical absorption” solely considered in Drude's theory of the optical constants of metals. Thus, it is possible to determine the “internal photoelectric effect” of the alkali metal potassium as a function of wavelength, espically its threshold frequency which corresponds to a wavelengthλ th=2·1 μ ( th=0·59 eV).  相似文献   

2.
The Eckart and Schrödinger proofs of 1926 are often described as having established the equivalence of wave mechanics and matrix mechanics as physical theories. The objective of this paper is to show that these “proofs” establish nothing of the kind. The Eckart-Schrödinger “proofs” have to do only with the formal identity of two different calculi. The question is, do the “proofs” establish the mathematical identity ofC 1 andC 2? Two views are possible: (1) Eckart and Schrödinger subsumed wave mechanics (C 1) and matrix mechanics (C 2) within a more comprehensive theory — which might be called “the operator calculus” (O). From this alone it does not follow thatC 1 andC 2 are formally identical. In general, the identity of two theories can never be established just by the fact that they both follow from the same premise. The other view (2) is thatO is simply a logical transformer which converts any statement ofC 1 into a corresponding statement ofC 2 — without adding any theoretical content of its own. That this is so could never beproved by an inductive selection of typical problems within microphysics; yet this is the actual procedure of Eckart and Schrödinger. Strictly speaking, one could consistently doubt thatC 1 andC 2 are ultimately identical even after sympathetically entertaining the Eckart-Schrödinger “proofs”. The really convincing argument for the equivalence asphysical theories of wave mechanics and matrix mechanics was provided by Born's statistical interpretation of theψ-function. Because here, in a frankly inductive procedure, Bornforces a physical interpretation onto bothC 1 andC 2 which at last makes it a matter of indifference which algorithm one chooses to express his predictions.  相似文献   

3.
We show how the abstract analytic number theory of Maier, Postnikov, and others can be extended to include negative numbers and apply this to thermodynamics, information theory, and human thermodynamics. In particular, we introduce a certain large number N 0 on the “zero level” with a high multiplicity number q i ? 1 related to the physical concept of gap in the spectrum. We introduce a general notion of “hole,” similar to the Dirac hole in physics, in the theory. We also consider analogs of thermodynamical notions in human thermodynamics, in particular, in connection with the role of the individual in history.  相似文献   

4.
Based on the perturbation theory and variational method long known for a “three-dimensional” atom, the ground and first excited state energies are calculated for a “one-dimensional” two-electron atom in the “one-dimensional ortho-helium” configuration, which can be obtained experimentally in principle, as has been already done for a Na Bose condensate, or produced in a super strong magnetic field B ? (2α)2B0 (B0 = m2c3/e? ≈ 4.41 × 1013 G). The “screening constant” σ for this atom in the ground and excited states was about 0.20 and 0.17, 0.18, respectively, depending on the relative parity PP' of the electronic states, which is somewhat smaller than in “two-dimensional” and “three-dimensional” variants (in these cases, this constant in the ground state is almost the same and about 0.3). The frequencies of the main spectral lines of a “onedimensional” He atom representing a doublet split over the relative parity PP' are found. The presence of the close lines of this doublet in the emission spectrum of magnetars at frequencies ω1, 2 ≈ {1.15; 1.17}α2(c/λC) (α = e2/?c, λC =?/mc) corresponding to the “one-dimensional ortho-helium” would suggest the existence of a superstrong magnetic field in such astrophysical objects.  相似文献   

5.
The forward asymmetry in the differential cross section for the photo disintegration of the deuteron has been calculated on the basis of a phenomenological theory for energies up to 80 MeV. The formulas for this asymmetry, which come from theE1-E2-andM1-M2-interference, are given, assuming the validity ofSiegert's theorem. TheE2-andM2-amplitudes are calculated approximately, using the Hulthén wavefunction with a 4% D-state admixture for the ground state and scattered waves determined by the phase shifts given by Marshak for the final states. The contribution of theM1-M2-interference turns out to be unimportant for the asymmetry, theE1-E2-interference giving the main effect. In the differential cross section,dσ/dΩ=a + b sin 2 ? + c cos ? + d cos ? sin 2 ?, we have obtained a very low value forc and the ratioc/d is approximately equal toa/3b. This is in contradiction to the assumptionc/d=a/b made in the previous analysis of the experimental data. This ratio seems to be insensitive to the value of the D-state admixture. For the lover energiesE γ=10 MeV andE γ=20 MeV the theoretical values for “d” are in agreement with the experimental ones. For the energies 54 and 80 MeV we have made a comparison of the theoretical differential cross sectiondσ/dΩ, taking into account the values for “a” and “b”, obtained in a former work ie, with the measureddσ/dΩ.  相似文献   

6.
We discuss the scenario where the X(3872) resonance is the \(c\bar c\) = χc1(2P) charmonium which “sits on” the D*0\({\bar D^0}\) threshold. We explain the shift of the mass of the X(3872) resonance with respect to the prediction of a potential model for the mass of the χc1(2P) charmonium by the contribution of the virtual D*\(\bar D\) + c.c. intermediate states into the self energy of the X(3872) resonance. This allows us to estimate the coupling constant of the X(3872) resonance with the D*0\({\bar D^0}\) channel, the branching ratio of the X(3872) → D*0\({\bar D^0}\) + c.c. decay, and the branching ratio of the X(3872) decay into all non-D*0\({\bar D^0}\) + c.c. states. We predict a significant number of unknown decays of X(3872) via two gluon: X(3872) → gluongluonhadrons. We suggest a physically clear program of experimental researches for verification of our assumption.  相似文献   

7.
The temperature dependence of the surface upper critical field,H c3, nearT c is calculated for arbitrary values of the mean free pathl by taking into account the fourthorder term of the generalized Ginzburg-Landau theory. For finitel the boundary condition is modified such that the normal derivative of the energy gap at the surface becomes positive. The slope of the curveH c3/H c2 versust=T/T c att=1 is found to decrease monotoneously from zero to ?1.040 as one goes from the “dirty” to the “clean” limit.  相似文献   

8.
Aim of this paper is to provide a scheme for the construction of a conceptual, virtual machine (the term has here a significance analogous to that of the Turing machine, i.e., a formal device which manipulates and evolves ‘states’), able to perform all that living matter – as distinguished from inert matter – can do and inanimate matter cannot, in a setting consistent exclusively with the quantum laws. In other words, the objective is to create a theoretical construct, in the form of a conceptual framework representing and providing the operational tools of a “\({\underline {\text {Life Machine}}}\)”.  相似文献   

9.
Using similar nonlinear stationary mean-field models for both a 2D axisymmetricalBose-Einstein Condensate and an electron pair in a parabolic trap, we propose to describethe original many-particle ground state as a one-particle mixed state (in contrast to apure state), i.e. as a statistical ensemble of several one-particle quantum states. Thesequantum states are the eigenfunctions of the corresponding stationary nonlinearSchrödinger equation (hence called “nonlinear eigenstates”). Due to their nonlinearity,they are not orthogonal. Therefore, taking the simple example of a two-level system, weshow that each of these two nonlinear eigenstates |i? and|j? occurs with a probability (or statistical weight) that isdefined by their non-orthogonality ?i|j? 0. We givethe corresponding density matrix. We search for physical grounds in the interpretation ofour two main results, namely, a quantum-classical nonlinear transition and theinterference between two “nonlinear eigenstates”.  相似文献   

10.
We provide a compact expression of the ground-state energy of N-Cooper pairs valid from small to large sample volumes, as checked by numerically solving Richardson-Gaudin equations which give the exact eigenstates of BCS superconductors. This expression contains a contribution linear in the potential amplitude, dominant for small samples, and an exponential contribution dominant when the number of states available for pairing gets larger than a material-dependent threshold independent from sample size. These “available states” are the states feeling the BCS potential, reduced by the Pauli exclusion principle through a “moth-eaten effect” which comes from the composite boson nature of Cooper pairs. This work also presents an elegant derivation of the N-Cooper pair energy obtained recently, which makes use of the roots of the degree-N Hermite polynomial.  相似文献   

11.
Finite Hamiltonian systems contain operators of position, momentum, and energy, having a finite number N of equally-spaced eigenvalues. Such systems are under the æis of the algebra su(2), and their phase space is a sphere. Rigid motions of this phase space form the group SU(2); overall phases complete this to U(2). But since N-point states can be subject to U(N) ?U(2) transformations, the rest of the generators will provide all N 2 unitary transformations of the states, which appear as nonlinear transformations—aberrations—of the system phase space. They are built through the “finite quantization” of a classical optical system.  相似文献   

12.
Let S be a set of states of a physical system. The probabilities p(s) of the occurrence of an event when the system is in different states sS define a function from S to [0, 1] called a numerical event or, more precisely, an S-probability. If one orders a set P of S-probabilities in respect to the order of functions, further includes the constant functions 0 and 1 and defines p′ = 1 ? p for every pP, then one obtains a bounded poset of S-probabilities with an antitone involution. We study these posets in respect to various conditions about the existence of the sum of certain functions within the posets and derive properties from these conditions. In particular, questions of relations between different classes of S-probabilities arising this way are settled, algebraic representations are provided and the property that two S-probabilities commute is characterized which is essential for recognizing a classical physical system.  相似文献   

13.
We construct the quantum density matrix of a spin-1/2 state for three given probability distributions describing positions of three classical coins and associate its matrix elements with the Triada of Malevich’s squares. We present the superposition principle of spin-1/2 states in the form of a nonlinear addition rule for these classical coin probabilities. We illustrate the obtained formulas by the statement “God does not play dice – God plays coins.”  相似文献   

14.
The problem of magnetic field penetration into the half-space is considered in parallel geometry in an external magnetic field increasing with time in accordance with the law B(0, t, τ0 = B c 1 (1 + t0) m , m ≥ 0, t ≥ 0 (τ 0 is the time of magnetic flux redistribution and B c 1 is the lower critical field). It is assumed that the flow of vortices is thermally activated in the “giant” creep mode (i.e., for weak pinning creep and high temperatures). A model equation is derived for describing the magnetic flux evolution. Analytic formulas are obtained for the depth and velocity of magnetic field penetration. It is shown that the giant creep regime is stable for 0 ≤ m ≤ 1/2.  相似文献   

15.
Many scholars maintain that the language of quantum mechanics introduces a quantum notion of truth which is formalized by (standard, sharp) quantum logic and is incompatible with the classical (Tarskian) notion of truth. We show that quantum logic can be identified (up to an equivalence relation) with a fragment of a pragmatic language \(\mathcal {L}_{G}^{P}\) of assertive formulas, that are justified or unjustified rather than trueor false. Quantum logic can then be interpreted as an algebraic structure that formalizes properties of the notion of empirical justification according to quantum mechanics rather than properties of a quantum notion of truth. This conclusion agrees with a general integrationist perspective that interprets nonstandard logics as theories of metalinguistic notions different from truth, thus avoiding incompatibility with classical notions and preserving the globality of logic.  相似文献   

16.
The classical model revealing stochastic resonance is a motion of an overdamped particle in a double-well fourth order potential when combined action of noise and external periodic driving results in amplifying of weak signals. Resonance behavior can also be observed in non-dynamical systems. The simplest example is a threshold triggered device. It consists of a periodic modulated input and noise. Every time an output crosses the threshold the signal is recorded. Such a digitally filtered signal is sensitive to the noise intensity. There exists the optimal value of the noise intensity resulting in the “most” periodic output. Here, we explore properties of the non-dynamical stochastic resonance in non-equilibrium situations, i.e. when the Gaussian noise is replaced by an α-stable noise. We demonstrate that non-equilibrium α-stable noises, depending on noise parameters, can either weaken or enhance the non-dynamical stochastic resonance.  相似文献   

17.
The properties of the Earth’s solid crust have been studied on the assumption that this crust has a block structure. According to the rotation model, the motion of such a medium (geomedium) follows the angular momentum conservation law and can be described in the scope of the classical elasticity theory with a symmetric stress tensor. A geomedium motion is characterized by two types of rotation waves with shortand long-range actions. The first type includes slow solitons with velocities of 0 ≤ Vsol ≤ c0, max = 1–10 cm s–1; the second type, fast excitons with V0VexVSVP. The exciton minimal velocity (V0 = 0) depends on the energy of the collective excitation of all seismically active belt blocks proportional to the Earth’s pole vibration frequency (the Chandler vibration frequency). The exciton maximal velocity depends on the velocities of S (VS ≈ 4 km s–1) and/or P (VP ≈ 8 km s–1) seismic (acoustic) waves. According to the rotation model, a geomedium is characterized by the property physically close to the corpuscular–wave interaction between blocks that compose this medium. The possible collective wave motion of geomedium blocks can be responsible for the geomedium rheidity property, i.e., a superplastic volume flow. A superplastic motion of a quantum fluid can be the physical analog of the geomedium rheid motion.  相似文献   

18.
The mechanical meaning and the relationships among material constants in an n-dimensional isotropic elastic medium are discussed. The restrictions of the constitutive relations (Hooke’s law) to subspaces of lower dimension caused by the conditions that an m-dimensional strain state or an m-dimensional stress state (1 ≤ m < n) is realized in the medium. Both the terminology and the general idea of the mathematical construction are chosen by analogy with the case n = 3 and m = 2, which is well known in the classical plane problem of elasticity theory. The quintuples of elastic constants of the same medium that enter both the n-dimensional relations and the relations written out for any m-dimensional restriction are expressed in terms of one another. These expressions in terms of the known constants, for example, of a three-dimensional medium, i.e., the classical elastic constants, enable us to judge the material properties of this medium immersed in a space of larger dimension.  相似文献   

19.
In the paper, a new construction of the theory of partitions of integers is proposed. The author defines entropy as the natural logarithm of the number of partitions of a number M into natural summands with repetitions allowed p(M) and repetitions forbidden q(M). The passage from ln p(M) to lnq(M) through the mesoscopic values M → 0 is studied. The topological transition from the mesoscopic lower levels of the Bohr–Kalckar construction to the macroscopic levels corresponding to the critical number of neutrons according to the consequence of Einstein’s inequality Mc N c , where c is determined for the particles of the given atomic nucleus. The role of quantum mechanics in establishing the new world outlook in physics is analyzed. It is pointed out that the main equations of thermodynamics in the volume “Statistical Physics” of the Landau–Lifshits treatise are obtained without appealing to the so-called “three main principles of thermodynamics”. It is also pointed out that Niels Bohr’s liquid model of the nucleus does not involve any interaction of particles in the form of attraction and is based on the presence of a common potential trough for all elements of the nucleus. The author constructs a new approach to thermodynamics, using quantum mechanics and the Earth’s gravitational attraction as a common potential trough.  相似文献   

20.
It is shown that the effective Lande splitting factor or g-factor of electrons localized on heterostructures such as small quantum dots is always formed as a difference of two values. The first of themrelates to thematerial of the dot itself and critically depends on its sizes and shape; the second one relates to the barriermaterial (surrounding matrix); therewith, the dependence on the latter does not disappear at any dot sizes. The known (k, p) Kane theory defining the renormalization of electron mass and g-factor in bulk semiconductors, is modified for small quantum dots with “incomplete” band structure. Specific calculations of the electron ground state energy and g-factor are performed for the covariant InAs/AlSb heterostructure not localizing holes and, hence, capable of forming pure one-electron states (prototypes of solid-state qubits).  相似文献   

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