Anatoliĭ Evgen'evich Levashev (Obituary)

Abstract

A temperatdre jump apparatds IS aescribed which is based ma'n y on commercially available components. TemperatJre jumps Of aOOUt 2 'C n aboLr 1 5 0~ of aqJe0-s solut'ons can oe produced w thin 10 ps by absorption of the nlrared radiation of a pulsed atom c iod ne aser. The I me range available for I( net c experiments :s aboJt 30 ps to 1 s. Tne necessaw moa fications 01 tne commercial iodine laser are discussed A prom nent IeatJre of the apparatds s the very hign sensit vity of the spectropnotometric detection system in the visible spectra range Signa -to-noise ratios of u p to 2 x 10' are reached at a time reso Jtion of 1 ps A metnod is described to aeterm ne tne size 01 the temperature .-mp of each ina vidLal exper ment. Thus not only the relaxation I mes wh.ch are ndependent of the s ze of sma I IemperatLre jumps. can be evaluatea OJI a so the corresponding relaxation amp IlJdeS can be determ ned in a precise manner FLrtnermore. an effective metnod to recyc e the .aser medium I-C,F,I IS describea.

Newtonian analogue of a Kerr black hole

“…During the golden era of black holes, when extensive mathematical studies had been performed, Israel [18] ended up in the oblate Euler field (without recognizing it as such) as the Newtonian analogue of Kerr metric by means of the right source distribution of the gravitational field. Actually the analogy between the two fields had been revealed even earlier by Keres [19], but it was mainly focused on finding similar properties related to the ring singularity of the then recently discovered Kerr metric and the corresponding avoidance of the ring singularity by geodesics. There was no demonstration of any connection between the two gravitational fields with respect to the orbital characteristics in them.…”

Constants of motion in stationary axisymmetric gravitational fields

“…(36). The potential (33) can be considered the Newtonian analogue (Keres 1967;Israel 1970;Lynden-Bell 2003;) of the Kerr solution in general relativity. The analogy is manifest when the Kerr metric is written in Kerr-Schild coordinates (Kerr & Schild 1965).…”

“…It will be demonstrated in section 2.6 that this class is essentially that of the Lagrange problem, that is, it amounts to the addition of a Hooke term to the potential. Israel (1970) and Keres (1967) have demonstrated that the dipole field of the Euler problem can be regarded as the Newtonian analogue of the Kerr solution in general relativity. Following Misner's suggestion to seek analogues of the quadratic constant in Newtonian dipole fields, Carter discovered his quadratic constant of motion in Kerr spacetime by separation of variables (Carter 1968(Carter , 1977Misner, Thorne, & Wheeler 1973).…”

Examples of Newtonian limits of relativistic spacetimes

“…The λ-family of spacetime models determined by (8) has an NC limit if and only if lim λ→0 k(λ) = k 0 exists [14]. If k 0 = 0, the angular momentum of the model diverges if λ → 0, for sufficiently small λ the spacetime contains closed timelike lines, and the limit spacetime (which was also constructed in a different way by Keres [21]) does not correspond to a physically acceptable, non-negative mass distribution. If all members of the family are assumed to be black holes-i.e.…”