[en] We consider the spectrum of the quantum asymmetric top. Unlike in the case when two or three moments of inertia are equal, when the moments of inertia are distinct all degeneracy in the spectrum of the operator is removed. We derive inequalities for the spectra based on recent results on the interlacing of Van Vleck zeros

[en] It is shown that the gravitational and inertial masses of a photon or, indeed, of any body are equal. Motion past and free fall onto a center of gravitational attraction are considered. (methodological notes)

[en] This book offers a thought-provoking approach to the fundamentals of relativity, and is structured to provide a clear-cut introduction to the essentials of relativistic mechanics. It seeks to emphasize the sensible content of concepts, to improve on their inherent or often forgotten fuzziness, and to explore prospects for their further exploitation. The work also provides an analysis conducive to a rigorous, normative definition of Time, which is seen as a synthesis of universal motion, instrumental in defining a general measure to transformations, and as a sufficient reason to suppose that the speed of light must be the same in all inertial reference frames - hence showing this cardinal postulate to be a demonstrable truth. Moreover it provides an augmented perception of what inertial vs. non-inertial systems are. In addition, the book offers a natural, time-like interpretation of Space that departs from the usual converse approach; it offers a self-consistent proposal to rationalize the axiomatic grounds of mechanics, based on a single postulate in conjunction with the overall approach developed. (author). refs.; figs.; tabs

No abstract available

[en] The results of the statistical investigation of the dependences of specific moment on galxies integral characteristics are presented, comparison of these relationships for different samples of isolated, double and triple galaxies is carried out

[en] The recent discovery of the very rapidly rotating pulsar PSR1937 + 214 has triggered off many theoretical speculations. Assuming that the pulsar is a fast-rotating superdense fluid it is shown here that the increase in the moment of inertia and in the gravitational self-energy of the spheroid due to its oblateness lead to substantial differences in the time evolution of the pulsar from that predicted by the standard models. Careful observations of its Psup(.), Psup(..) and its spectrum can put constraints on the properties of neutron star matter. Even with the existing observation of P = 1.56 ms, considerations of dynamical stability of the rapidly rotating neutron star yield a lower limit p-bar > 1.7 x 10¹⁴ g cm^-3 for the mean stellar density. (author)

[en] The objective of this study is to understand the role that changes in body moment of inertia might play during flight manoeuvres of insects. High-speed, high-resolution videogrammetry is used to quantify the trajectory and body conformation of Painted Lady butterflies during flight manoeuvres; the 3D kinematics of the centre of masses of the various body parts of the insect is determined experimentally. Measurements of the mass properties of the insect are used to parameterize a simple flight dynamics model of the butterfly. Even though the mass of the flapping wings is small compared to the total mass of the insect, these experiments and subsequent analysis indicate that changes in moment of inertia during flight are large enough to influence the manoeuvres of these insects. (communication)

No abstract available

[en] The intersecting crossing band structure of the backbending nucleus ¹⁶⁴Er is illustrated

[en] Here, an analytical approach for the dynamic analysis, viz., free and forced vibrations, of curved nanobeams using nonlocal elasticity beam theory based on Eringen formulation coupled with a higher-order shear deformation accounting for through thickness stretching is investigated. The formulation is general in the sense that it can be deduced to analyse the effect of various structural theories pertaining to curved nanobeams. It also includes inplane, rotary and coupling inertia terms. The governing equations derived, using Hamiltons principle, are solved in conjunction with Naviers solutions. The free vibration results are obtained employing the standard eigenvalue analysis whereas the displacement/stress responses in time domain for the curved nanobeams subjected to rectangular pulse loading are evaluated based on Newmarks time integration scheme. The formulation is validated considering problems for which solutions are available. A comparative study is done here by different theories obtained through the formulation. The effects of various structural parameters such as thickness ratio, beam length, rise of the curved beam, loading pulse duration, and nonlocal scale parameter are brought out on the dynamic behaviours of curved nanobeams.