Photometry of the solar corona of March 7, 1970

Isophotes obtained by equidensitometry techniques from four exposures of the March 7, 1970 corona are used for derivation of intensity distributions along the equator, poles, streamers and dark ‘gaps’ in the visible corona. The distributions differ from the van de Hulst curves for a maximum corona. The Kodaikanal measures agree well with the NRL measures of the outer corona made from a rocket coronagraph and together provide data from 1·2R_⊙ to 8·0R_⊙ along the solar equator. Radial intensity gradients for different position angles and the Ludendorff parameters obtained, characterize this corona as typical of the solar maximum.     

Field theoretic calculation of energy cascade rates in non-helical magnetohydrodynamic turbulence

Energy cascade rates and Kolmogorov’s constant for non-helical steady magnetohydrodynamic turbulence have been calculated by solving the flux equations to the first order in perturbation. For zero cross helicity and space dimensiond = 3, magnetic energy cascades from large length-scales to small length-scales (forward cascade). In addition, there are energy fluxes from large-scale magnetic field to small-scale velocity field, large-scale velocity field to small-scale magnetic field, and large-scale velocity field to large-scale magnetic field. Kolmogorov’s constant for magnetohydrodynamics is approximately equal to that for fluid turbulence (≈ 1.6) for Alfvén ratio 05 ≤r _A ≤ ∞. For higher space-dimensions, the energy fluxes are qualitatively similar, and Kolmogorov’s constant varies asd ^1/3. For the normalized cross helicity σ_c →1, the cascade rates are proportional to (1 − σ_c)/(1 + σ_c , and the Kolmogorov’s constants vary significantly with σ_cc.     

Conformal invariance and scalar-tensor theories

A new generalisation of Einstein’s theory is proposed which is invariant under conformal mappings. Two scalar fields are introduced in addition to the metric tensor field, so that two special choices of gauge are available for physical interpretation, the ‘Einstein gauge’ and the ‘atomic gauge’. The theory is not unique but contains two adjustable parameters ζ anda. Witha=1 the theory viewed from the atomic gauge is Brans-Dicke theory (ω=−3/2+ζ/4). Any other choice ofa leads to a creation-field theory. In particular the theory given by the choicea=−3 possesses a cosmological solution satisfying Dirac’s ‘large numbers’ hypothesis.     

Nonexistence of Marginally Trapped Surfaces and Geons in 2 + 1 Gravity

We use existence results for Jang’s equation and marginally outer trapped surfaces (MOTSs) in 2 + 1 gravity to obtain nonexistence of geons in 2 + 1 gravity. In particular, our results show that any 2 + 1 initial data set, which obeys the dominant energy condition with cosmological constant Λ ≥ 0 and which satisfies a mild asymptotic condition, must have trivial topology. Moreover, any data set obeying these conditions cannot contain a MOTS. The asymptotic condition involves a cutoff at a finite boundary at which a null mean convexity condition is assumed to hold; this null mean convexity condition is satisfied by all the standard asymptotic boundary conditions. The results presented here strengthen various aspects of previous related results in the literature. These results not only have implications for classical 2 + 1 gravity but also apply to quantum 2 + 1 gravity when formulated using Witten’s solution space quantization.     

Reality in quantum mechanics,Extended Everett Concept,and consciousness

Conceptual problems in quantum mechanics result from the specific quantum concept of reality and require, for their solution, including the observer’s consciousness into the quantum theory of measurements. Most naturally, this is achieved in the framework of Everett’s “many-world interpretation” of quantum mechanics. According to this interpretation, various classical alternatives are perceived by consciousness separately from each other. In the Extended Everett Concept (EEC) proposed by the present author, the separation of the alternatives is identified with the phenomenon of consciousness. This explains the classical character of the alternatives and unusual manifestations of consciousness arising “at the edge of consciousness” (i.e., in sleep or trance) when its access to “other alternative classical realities” (other Everett’s worlds) becomes feasible. Because of reversibility of quantum evolution in EEC, all time moments in the quantum world are equivalent, while the impression of flow of time appears only in consciousness. If it is assumed that consciousness may influence the probabilities of alternatives (which is consistent in case of infinitely many Everett’s worlds), EEC explains free will, “probabilistic miracles” (observing low-probability events), and decreasing entropy in the sphere of life. The text was submitted by the author in English.     

Vector mesons in matter

One consequence of the chiral restoration is the mixing of parity partners. We look for a possible signature of the mixing of vector and axial vector mesons in heavyion collisions. We suggest an experimental method for its observation. The dynamical evolution of the heavy-ion collision is described by a transport equation of QMD-type evolving nucleons,N* and Δ resonances, Λ’s and gS baryons, and furthermore,π’s,η’sρ’sσ’sΩ’s and kaons with their isospin degrees of freedom. The input cross-sections and resonance parameters of the model are fitted to the available nucleon-nucleon and pion-nucleon cross-sections     

Fifty years of Szigeti’s dielectric theory — A review

During the period 1949–1961 Szigeti published four seminal papers on the dielectric behaviour of crystals. Szigeti’s theory is applicable to isotropic and anisotropic, ionic and covalent crystals with different structures. Szigeti’s theory connects dielectric, spectroscopic and elastic properties. An important outcome of Szigeti’s theory is the concept of the effective ionic charge (s). It is pointed out that s correlates with a number of physical properties and is a measure of ionicity of the interatomic bond. Since Szigeti’s work, several theoretical models have been proposed to account for the fact that s < 1. These models provide an insight into the complex polarization mechanisms in solids. This review summarizes Szigeti’s work and the work that followed; the implications and applications of Szigeti’s theory are discussed. Some new results are also included. Dedicated to the memory of late Prof. P S Narayanan.     

Ensembles of plasmonic nanospheres at optical frequencies and a problem of negative index behavior

Arrays of metallic nanoparticles support individual and collective plasmonic excitations that contribute to unusual phenomena like surface-enhanced Raman scattering, anomalous transparency, negative index, and subwavelength resolution in various metamaterials. We examined the electromagnetic response of dual Kron’s lattice and films containing up to three monolayers of metallic nanospheres. It appears that open cubic Kron’s lattice exhibits ‘soft’ electromagnetic response but no negative index behavior. The close-packed arrays behave similarly: there are plasmon resonances and very high transmission at certain wavelengths that are much larger than the separation between the particles, and a ‘soft’ magnetic response, with small but positive effective index of refraction. It would be interesting to check these predictions experimentally. PACS 78.20.Ci; 42.30.Wb; 73.20.Mf; 42.25.Bs     

Choice of optimal exposures in photographing the earth’s surface by multispectral photographic equipment

An analysis of radiation fluxes entering the image plane of the spectral channels of multispectral photographic equipment (MSPE) used in photographing the earth’s surface from space, the illumination intensity levels created by these fluxes, and the degree of blackening of photographic materials depending on the exposure has been carried out. The method of selecting the optimal values for the exposure time in photographing various classes of the earth’s surface in each spectral channel of MSPE is proposed. Using the spectra of brightness, measured from aboard the orbital Salyut-7 and Mir stations, evaluations of the optimal exposure time of the basic classes of the earth’s surface depending on optical parameters of the MSPE were made. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 1, pp. 111–116, January–February, 2000.     

Influence of anisotropy on the dispersion of surface plasmon-phonon polaritons in silicon carbide

Surface plasmon-phonon polaritons (SPPP’s) of types 3 and 4 are investigated in doped anisotropic single crystals of hexagonal silicon carbide (6H-SiC) in the orientation corresponding to K⊥C and xy⊥C. It is shown that a dispersion dependence of the type-3 SPPP’s bounded by K appears in 6H-SiC when the plasmon frequency increases to ν _p⊥⩾350 cm⁻¹. At ν _p⊥⩾400 cm⁻¹, ν _s(K) exists for type-4 SPPP’s in the frequency range Ω _∥ ⁺ <ν< _⊥ ⁺ . When the concentration of free charge carriers is increased, the dispersion curves are displaced toward higher frequencies. The conditions for the existence of type-3 and type-4 SPPP’s in 6H-SiC are determined. Fiz. Tverd. Tela (St. Petersburg) 40, 636–639 (April 1998)     

Investigation of the structural transformations in the Al-Li-Cu-Mg (8090) alloy

q =803 K) have been investigated via the Vickers microhardness measurements, scanning electron microscopy and differential scanning calorimetry. On the basis of Kissinger’s analytical equation of the DSC thermograms, the overall activation energies associated with the transformation processes are evaluated. The activation energy associated with the formation of the GPB zones and δ’ phase is determined as 82.433 kJ/mol. Whereas the energy of their dissolution is 139.78 kJ/mol. The activation energy associated with the formation of the S’ phase is determined as 106.88 kJ/mol. In addition, the microstructural examination of the samples after various aging temperatures revealed that the resultant precipitates are intergranular. Received: 27 September 1996/Accepted: 20 January 1997     

Leaky modes and their contributions to the compressional head wave in a borehole excited by a dipole source

A method of studying the contributions of leaky modes to the wave field is presented based on the analysis of the Riemann surface structure of the characteristic function, and the sensitivities of con- tributions to various factors of interest are examimed. Numerical results show that their contributions to the compressional head wave are related to the distributions of complex poles on (-1, -1) and (0, -1) Riemann sheets on the frequency-wavenumber (ω - k) plane. For fast formations, their contributions ar...     

Thermal neutron flux monitoring using new-type detectors

The applicability of new-type unshielded detectors based on zinc sulfide ZnS(Ag) and lithium fluoride enriched with ⁶Li isotope to 90% to thermal neutron measurements is demonstrated. The results of measurements of the thermal neutron counting rate and flux near the Earth’s surface are presented. The existence of the concentration gradient of thermal neutrons near the Earth’s surface at placing the counter at the various levels (from −4 to 10.5 m) in an experimental building is shown. The effect of meteoparameters on the counting rate of thermal neutrons for a long time is shown.     

Infinity and Newton’s Three Laws of Motion

It is shown that the following three common understandings of Newton’s laws of motion do not hold for systems of infinitely many components. First, Newton’s third law, or the law of action and reaction, is universally believed to imply that the total sum of internal forces in a system is always zero. Several examples are presented to show that this belief fails to hold for infinite systems. Second, two of these examples are of an infinitely divisible continuous body with finite mass and volume such that the sum of all the internal forces in the body is not zero and the body accelerates due to this non-null net internal force. So the two examples also demonstrate the breakdown of the common understanding that according to Newton’s laws a body under no external force does not accelerate. Finally, these examples also make it clear that the expression ‘impressed force’ in Newton’s formulations of his first and second laws should be understood not as ‘external force’ but as ‘exerted force’ which is the sum of all the internal and external forces acting on a given body, if the body is infinitely divisible.     

Dielectric relaxation of binary polar liquid mixture measured in benzene at 10 GHz frequency

The dielectric relaxation times τ _jk ’s and dipole moments μ _jk ’s of the binary (jk) polar liquid mixture of N,N-dimethyl acetamide (DMA) and acetone (Ac) dissolved in benzene (i) are estimated from the measured real σ′ _ijk and imaginary σ″ _ijk parts of complex high frequency conductivity σ* _ijk of the solution for different weight fractions w _jk ’s of 0.0, 0.3, 0.5, 0.7 and 1.0 mole fractions x _j of Ac and temperatures (25, 30, 35 and 40°C) respectively under 9.88 GHz electric field. τ _jk ’s are obtained from the ratio of slopes of σ″ _ijk -w _jk and σ′ _ijk -w _jk curves at w _jk → 0 as well as linear slope of σ″ _ijk -σ′ _ijk curves of the existing method (Murthy et al, 1989) in order to eliminate polarpolar interaction in the latter case. The calculated τ’s are in excellent agreement with the reported τ’s due to Gopalakrishna’s method. μ _jk ’s are also estimated from slopes β’s of total conductivity σ _ijk -w _jk curves at w _jk → 0 and the values agree well with the reported μ’s from G.K. method. The variation of τ _jk ’s and μ _jk ’s with x _j of Ac reveals that solute-solute molecular association occurs within 0.0–0.3x _j of Ac beyond which solute-solvent molecular association is predicted. The theoretical dipole moments μ _theo’s are calculated from bond angles and bond moments to have exact μ’s only to show the presence of inductive, mesomeric and electromeric effects in the substituent polar groups. The thermodynamic energy parameters are estimated from ln(τ _jk T) against 1/T linear curve from Eyring’s rate theory to know the molecular dynamics of the system and to establish the fact that the mixture obeys the Debye-Smyth relaxation mechanism.      

Hydrostatic pressure and thermal loading induced long-term optical effects in tightly jacketed double-coated optical fibers

By the viscoelastic theory, the hydrostatic pressure and thermal loading simultaneously induced optical effects in tightly jacketed double-coated optical fibers in the long term are analyzed. Using the Laplace transformation method, close-form solutions for the microbending loss and refractive index changes are obtained in the transform domain. The results of the microbending loss are initially identical to those obtained by the elastic analysis, and then decrease gradually as time progresses. The microbending loss and refractive index changes of the glass fiber are functions of material properties of the coating layers and jacket. To minimize the microbending loss and refractive index changes in the long term, the viscosity ratio η₃/η₁, Young’s modulus ratio E₂/E₁ and E₃/E₁, and ratio of Poisson’s ratio ν₃/ν₁ should be increased. Nevertheless, the ratio of Poisson’s ratio ν₂/ν₁ should be decreased. PACS 42.79.Wc; 61.20.Lc; 68.65.Ac     

Spherically symmetric static solutions of the Einstein-Maxwell equations

We report a new formalism to obtain solutions of Einstein-Maxwell’s equations for static spheres assuming the matter content to be a charged perfect fluid of null-conductivity. Defining three new variablesu=4πεr ²,ν=4πpr ^{2 2} andw=(4π/3)(ρ+ε)r ² whereε, ρ andε denote respectively energy densities of the electric, matter and free gravitational fields whereasp is the fluid pressure, Einstein’s field equations are rewritten in an elegant form. The solutions given by Bonnor [1], Nduka [2], Cooperstock and De la Cruz [3], Mehra [4], Tikekar [5,6], Xingxiang [7], Patino and Rago [8] are all shown to possess simple relations betweenu, v, andw whereas Pant and Sah’s [9] solution for which all the three functions,u, v, andw are constants is a trivial case of the present formalism, We have presented six new solutions with ε = 2ρ. For the first three solutionsw andu are constants withv as a variable whereas the remaining three solutions satisfy the equation of state for isothermal gas;v =kw =-ku where (i)k is an arbitrary constant but not equal to 1 or 1/3 (ii)k = 1 and (iii)k = 1/3. We also obtained a generalization of Cooperstock and De la Cruz’s [3] solution which is regular for 2ρ > ε but singular for 2ρ ≤ ε.     

Time Variable Λ and the Accelerating Universe

We perform a deductive study of accelerating Universe and focus on the importance of variable time-dependent Λ in the Einstein’s field equations under the phenomenological assumption, Λ=αH ² for the full physical range of α. The relevance of variable Λ with regard to various key issues like dark matter, dark energy, geometry of the field, age of the Universe, deceleration parameter and barotropic equation of state has been trivially addressed. The deceleration parameter and the barotropic equation of state parameter obey a straight line relationship for a flat Universe described by Friedmann and Raychaudhuri equations. Both the parameters are found identical for α=1.