Field approach to gravitation and its significance in astrophysics     

Vladimír Majerník 《Astrophysics and Space Science》1971,14(2):265-285

A field modification of classical gravitational theory which is analogous to the classical electrodynamics is proposed. Within its framework it is possible to account for some types of behaviour of matter occurring under certain extreme physical conditions. Especially, the energy release in quasars and pulsars may be calculated, under some plausible physical assumptions, to obtain values comparable with the observable ones. Several astrophysical effects (e.g. the occurrence of non-thermal radiation in pulsars and quasars, etc.) find reasonable explanations within this field approach to gravitation.  相似文献   

Propagation of light in a Maxwell-like gravitational field     

Vladimír Majerník 《Astrophysics and Space Science》1982,82(2):473-476

We propose a coupling between the gravitational and electromagnetic fields so that we consider the electrodynamical Maxwell's equations as the basic ones and add the four-vector of gravitational potential to the differential operators occurring in it. It is shown that by means of this coupling all well-known tests of Einstein's theory of gravitation connected with the propagation of light in gravitational field can be correctly calculated.  相似文献   

Model of the expansive nondecelerative universe     

Vladimír Skalský  Miroslav Súkeník 《Astrophysics and Space Science》1991,178(1):169-171

The joint article is concerned with derivation of equations of dynamics of the expansive nondecelerative universe and determination of its basic properties, relations, and parameters with the state equationp=–1/3.  相似文献   

Local magnitude,surface wave magnitude and seismic energy     

Vladimír Tobyáš  Reinhard Mittag 《Studia Geophysica et Geodaetica》1991,35(4):354-357

Summary The local magnitude M_L at the seismological station Pruhonice (PRU) was converted into surface wave magnitude M_S using the formula M_S=–3.2+1.45 M_L and the seismic wave energy was estimated using the relation log E (Joule)=1.2+2.0 M_L. It was proposed to apply the same conversion formulae at seismological stations Kaperské Hory (KHC) and Berggiesshübel (BRG) where the calibrating functions for local magnitudes were determined for the same set of earthquakes with common reference magnitudes as in the case of the PRU station.  相似文献   

Relation between macroseismic intensity and instrumental parameters of strong motions — A statistical approach     

Vladimír Schenk  František Mantlík  Michail N. Zhizhin  Alexey G. Tumarkin 《Natural Hazards》1990,3(2):111-124

One hundred and twenty-eight strong ground motion CALTECH (Earthquakes in the U.S.A., 1940–1971) records of five Californian earthquakes, recorded at ground level and in basements, for which the modified Mercalli macroseismic intensities are known, were statistically processed to calculate 165 wave parameters. Correlation of the peak values of particle acceleration, velocity and displacement, energy, impulse and root-mean-square amplitude of the vibrations, durations of vibrations for certain levels of the peak amplitude, and spectral energies of 10 frequency windows with macroseismic intensity are discussed from the viewpoint of classification of ground-motion records.Paper presented at the 21st General Assembly of the European Seismological Commission held in Sofia 1988.  相似文献   

Gravity and inertia     

Vladimír Skalský 《Astrophysics and Space Science》1990,166(1):159-164

Inertia field is universal; this is why it can be in a state with energy as well as in a state without energy. Gravitational field is secondary and it occurs only with the appearance of particles with energy.  相似文献   

Mineralogy,petrography, geochemistry,and classification of the Košice meteorite          下载免费PDF全文

Daniel Ozdín  Jozef Plavčan  Michaela Horňáčková  Pavel Uher  Vladimír Porubčan  Pavel Veis  Jozef Rakovský  Juraj Tóth  Patrik Konečný  Ján Svoreň 《Meteoritics & planetary science》2015,50(5):864-879

The Ko?ice meteorite was observed to fall on 28 February 2010 at 23:25 UT near the city of Ko?ice in eastern Slovakia and its mineralogy, petrology, and geochemistry are described. The characteristic features of the meteorite fragments are fan‐like, mosaic, lamellar, and granular chondrules, which were up to 1.2 mm in diameter. The fusion crust has a black‐gray color with a thickness up to 0.6 mm. The matrix of the meteorite is formed mainly by forsterite (Fo_80.6); diopside; enstatite (Fs_16.7); albite; troilite; Fe‐Ni metals such as iron and taenite; and some augite, chlorapatite, merrillite, chromite, and tetrataenite. Plagioclase‐like glass was also identified. Relative uniform chemical composition of basic silicates, partially brecciated textures, as well as skeletal taenite crystals into troilite veinlets suggest monomict breccia formed at conditions of rapid cooling. The Ko?ice meteorite is classified as ordinary chondrite of the H5 type which has been slightly weathered, and only short veinlets of Fe hydroxides are present. The textural relationships indicate an S3 degree of shock metamorphism and W0 weathering grade. Some fragments of the meteorite Ko?ice are formed by monomict breccia of the petrological type H5. On the basis of REE content, we suggest the Ko?ice chondrite is probably from the same parent body as H5 chondrite Morávka from Czech Republic. Electron‐microprobe analysis (EMPA) with focused and defocused electron beam, whole‐rock analysis (WRA), inductively coupled plasma mass and optical emission spectroscopy (ICP MS, ICP OES), and calibration‐free laser induced breakdown spectroscopy (CF‐LIBS) were used to characterize the Ko?ice fragments. The results provide further evidence that whole‐rock analysis gives the most accurate analyses, but this method is completely destructive. Two other proposed methods are partially destructive (EMPA) or nondestructive (CF‐LIBS), but only major and minor elements can be evaluated due to the significantly lower sample consumption.  相似文献   

Influence of crack distribution of rocks on P‐wave velocity anisotropy – a laboratory and field scale study‡     

Jan Vilhelm  Vladimír Rudajev  Roman Živor  Tomáš Lokajíček  Zdeněk Pros 《Geophysical Prospecting》2010,58(6):1099-1110

The purpose of this paper is the comparison of P‐wave velocity and velocity anisotropy, measured at different scales under laboratory and field conditions. A shallow seismic refraction survey with shot/receiver spacing of up to 10 m was carried out on a flat outcrop of lhertzolite in the southern part of the Balmuccia massif. Oriented rock samples were also obtained from the locality. The particular advantage of the laboratory method used is the possibility of measuring velocity in any direction under controlled conditions. Laboratory tests were made on spherical peridotite samples, 50 mm in diameter, by ultrasonic velocity measurements in 132 directions (meridian and parallel networks) under confining stress ranging from atmospheric to 400 MPa. The mean P‐wave velocity of the field and laboratory data differed by between 20–30%. In addition, P‐wave velocity anisotropy of 25% was detected in the field data. Whereas the anisotropy in the laboratory samples in the same orientation as the field surveys was less than 2%. This observed scaling factor is related to the different sampling sizes and the difference in frequencies of applied elastic waves. With an ultrasonic wavelength of 10 mm, laboratory samples represent a continuum. The field velocities and velocity anisotropy reflect the presence of cracks, which the laboratory rock samples do not contain. Three sub‐vertical fracture sets with differing strikes were observed in the field outcrop. Estimates of fracture stiffness from the velocity anisotropy data are consistent with other published values. These results highlight the difficulty of using laboratory velocity estimates to interpret field data.  相似文献   

A note on the problem of choosing a model of the Universe,II     

Vladimŕ Skalský 《Astrophysics and Space Science》1989,154(1):149-151

The energy balance in the solar maximum corona discussed by Narain and Kumar (1986) is objectionable. Hence, the conclusions drawn by them may not be reliable.  相似文献   

Matter-space-time properties of the Universe     

Vladimír Skalský 《Astrophysics and Space Science》1994,219(2):275-289

In the expansive nondecelerative homogeneous and isotropic relativistic Universe there take place: the permanent constant maximum possible creation of matter, the relativistic increase of mass of expanding objects, the relativistic dilatation of time of expanding objects, the relativistic contraction of radial length of expanding objects, and the relativistic dilatation of angular dimensions of expanding remote objects.Editor's Note: The delay in publishing this paper was due to an unfortunate oversight connected with the late Professor Kopal's death.  相似文献