We study the string propagation in the 2+1 black hole anti de Sitter background (2+1 BH-ADS). We find the first and second order fluctuations around the string center of mass and obtain the expression for the string mass. The string motion is stable, all fluctuations oscillate with real frequencies and are bounded, even at r = 0. We compare with the string motion in the ordinary black hole anti...

background: the aim of this study was to investigate muscle damage indicators and electromyography activities of quadriceps muscles at 25° of hip flexion in untrained healthy females after an eccentric exercise induced muscle fiber damage.   methods : a total of 14 healthy females participated in this pre-experimental study. the subjects performed maximal eccentric quadriceps contractions at 25...

The effect of gravitational radiation reaction on orbits around a spinning black hole is analyzed. Such orbits possess three constants of motion: i , e , and a , which correspond, in the Newtonian limit of the orbit being an ellipse, to the inclination angle of the orbital plane to the hole’s equatorial plane, the eccentricity, and the semimajor axis length, respectively. First, it is argued th...

Hawking has shown that the emission of gravitational radiation cannot prevent circular loops of gauged cosmic strings from collapsing into black holes. Here we consider the corresponding question for global strings: can Goldstone boson emission prevent circular loops of global cosmic strings from forming black holes? Our results show that for every value of the string tension there is a certain...

The formation and growth of supermassive black holes is a key issue to unveil the secrets of galaxy formation. In particular, the gravitational recoil produced in the merger of unequal mass black hole binaries could have a number of astrophysical implications, such as the ejection of black holes from the host galaxy or globular cluster. We present estimates of the recoil velocity that include t...

Owing to the difficulty of direct observation, mergers of intermediate-mass black hole binaries are relatively less understood compared to stellar-mass binaries; however, the gravitational waves from their last few orbits and ringdown fall in the band of ground-based detectors. Because the typical source is expected to circularize prior to entering LIGO or VIRGO’s range, inspiral searches conce...

We present Hubble Space Telescope (HST) spectroscopy of the nucleus of M 31 obtained with the Space Telescope Imaging Spectrograph (STIS). Spectra that include the Ca II infrared triplet (λ ≃ 8500 Å) see only the red giant stars in the double brightness peaks P1 and P2. In contrast, spectra taken at λλ ≃ 3600 – 5100 Å are sensitive to the tiny blue nucleus embedded in P2, the lower-surface-brig...

OBJECTIVE To carry out isolated and comparative evaluations of the measurements of the set eccentric guide plates used in 4.5mm surgical implants, and to determine the effect of these measurements on compression strength. METHODS Four eccentric guides, four large dynamic compression plates (L-DCP) from four local manufacturers, and a Vonder(®) 200 mm caliper brand were used. Five standard par...

The gravitational three-body problem is a fundamental in physics and has significant applications to astronomy. Three-body configurations are often considered stable as long the system hierarchical; that is, two orbital distances well-separated. However, instability, which associated with energy exchange between orbits, takes time develop. Assuming massive objects circular orbit test particle a...

We calculate the eccentricity dependence of high-order post-Newtonian (PN) expansion spin-precession invariant $\psi$ for eccentric-orbit extreme-mass-ratio inspirals with a Schwarzschild primary. The series is calculated in first-order black hole perturbation theory through direct analytic solutions Regge-Wheeler-Zerilli formalism, using code written \textsc{Mathematica}. Modes small values $l...