[1401.3711] A Be-type star with a black hole companion:
Stellar-mass black holes have all been discovered through X-ray emission, which arises from the accretion of gas from their binary companions (this gas is either stripped from low-mass stars or supplied as winds from massive ones). Binary evolution models also predict the existence of black holes accreting from the equatorial envelope of rapidly spinning Be-type stars (stars of the Be type are hot blue irregular variables showing characteristic spectral emission lines of hydrogen). Of the ~80 Be X-ray binaries known in the Galaxy, however, only pulsating neutron stars have been found as companions. A black hole was formally allowed as a solution for the companion to the Be star MWC 656 (also known as HD 215227), although that was based on a single radial velocity curve of the Be star, a mistaken spectral classification and rough estimates of the inclination angle. Here we report observations of an accretion disk line mirroring the orbit of the Be star. This, together with an improved radial velocity curve of the Be star through fitting sharp Fe II profiles from the equatorial disk, and a refined Be classification (to that of a B1.5-B2 III star), reveals a black hole of 3.8 to 6.9 solar masses orbiting MWC 656, the candidate counterpart of the gamma-ray source AGL J2241+4454. The black hole is X-ray quiescent and fed by a radiatively inefficient accretion flow giving a luminosity less than 1.6 x 10-7 times the Eddington luminosity. This implies that Be binaries with black-hole companions are difficult to detect by conventional X-ray surveys.
'via Blog this'
Monday, January 27, 2014
[astro-ph/0701358] Dark Matter in an n-Space Expanding Universe
[astro-ph/0701358] Dark Matter in an n-Space Expanding Universe:
The total number of degrees of freedom of a d-dimensional body in n-space is derived so that equipartition of energy may be applied to a possibly n-dimensional early universe. A comparison is made of a range of proposals to include free and bound black holes as either a small component or the dominant constituent of dark matter in the universe. The hypothesis that dark matter consists in part of atomic gravitationally bound primordial black holes is closely examined in 3-space, as well as in n-space; and the Chavda and Chavda holeum hypothesis is found to be flawed. Blackbody and Hawking radiation are generalized to n-space, and Hawking radiation is shown to be simply proportional to the black hole density. The importance of quantum gravity in understanding the role of early universe dark matter is undermined because present approaches to a theory of quantum gravity violate the equivalence principle. A general heuristic proof for geodesics on an expanding hypersphere is presented. Classical limits of Einstein's General Relativity are considered. A novel approach to the accelerated expansion of the universe is discussed. An anomalous surprising aspect of 4-space is demonstrated.
'via Blog this'
The total number of degrees of freedom of a d-dimensional body in n-space is derived so that equipartition of energy may be applied to a possibly n-dimensional early universe. A comparison is made of a range of proposals to include free and bound black holes as either a small component or the dominant constituent of dark matter in the universe. The hypothesis that dark matter consists in part of atomic gravitationally bound primordial black holes is closely examined in 3-space, as well as in n-space; and the Chavda and Chavda holeum hypothesis is found to be flawed. Blackbody and Hawking radiation are generalized to n-space, and Hawking radiation is shown to be simply proportional to the black hole density. The importance of quantum gravity in understanding the role of early universe dark matter is undermined because present approaches to a theory of quantum gravity violate the equivalence principle. A general heuristic proof for geodesics on an expanding hypersphere is presented. Classical limits of Einstein's General Relativity are considered. A novel approach to the accelerated expansion of the universe is discussed. An anomalous surprising aspect of 4-space is demonstrated.
'via Blog this'
Sunday, January 26, 2014
Gravity
This note is NOT about Alfonso Cuaron's movie. Go see it though, it is good. It is about the difference between this force and the other three known forces, nuclear-strong, nuclear-weak, and electromagnetic. I posted a video on the possibility that atoms are black-holes.
There is a puzzle in Physics right now, the atomic nucleus of Hydrogen, seems to have two different sizes, if we measure it with electrons, or with its weak cousin, the muon. So far no differences had been found between these two particles, leading the great physicist Isidor Rabi to ask, who ordered that? The new puzzle may answer this old question.
According to Roberto Onofrio, there is a way to test if muons, and electrons interact differently with the proton, due to a new component of Gravity.
That'll be neat.
The black hole bit, though, is another story altogether.
There is a puzzle in Physics right now, the atomic nucleus of Hydrogen, seems to have two different sizes, if we measure it with electrons, or with its weak cousin, the muon. So far no differences had been found between these two particles, leading the great physicist Isidor Rabi to ask, who ordered that? The new puzzle may answer this old question.
According to Roberto Onofrio, there is a way to test if muons, and electrons interact differently with the proton, due to a new component of Gravity.
That'll be neat.
The black hole bit, though, is another story altogether.
Sunday, January 12, 2014
[1301.3808] Formation of Regular Satellites from Ancient Massive Rings in the Solar System
[1301.3808] Formation of Regular Satellites from Ancient Massive Rings in the Solar System:
"When a planetary tidal disk -like Saturn's rings- spreads beyond the Roche radius (inside which planetary tides prevent aggregation), satellites form and migrate away. Here, we show that most regular satellites in the solar system probably formed in this way. According to our analytical model, when the spreading is slow, a retinue of satellites appear with masses increasing with distance to the Roche radius, in excellent agreement with Saturn's, Uranus', and Neptune's satellite systems. This suggests that Uranus and Neptune used to have massive rings that disappeared to give birth to most of their regular satellites. When the spreading is fast, only one large satellite forms, as was the case for Pluto and Earth. This conceptually bridges the gap between terrestrial and giant planet systems."
'via Blog this'
"When a planetary tidal disk -like Saturn's rings- spreads beyond the Roche radius (inside which planetary tides prevent aggregation), satellites form and migrate away. Here, we show that most regular satellites in the solar system probably formed in this way. According to our analytical model, when the spreading is slow, a retinue of satellites appear with masses increasing with distance to the Roche radius, in excellent agreement with Saturn's, Uranus', and Neptune's satellite systems. This suggests that Uranus and Neptune used to have massive rings that disappeared to give birth to most of their regular satellites. When the spreading is fast, only one large satellite forms, as was the case for Pluto and Earth. This conceptually bridges the gap between terrestrial and giant planet systems."
'via Blog this'
Monday, January 6, 2014
[astro-ph/0209276] Dynamical derivation of Bode's law
[astro-ph/0209276] Dynamical derivation of Bode's law:
"In a planetary or satellite system, idealized as n small bodies in initially coplanar, concentric orbits around a large central body, obeying Newtonian point-particle mechanics, resonant perturbations will cause dynamical evolution of the orbital radii except under highly specific mutual relationships, here derived analytically apparently for the first time. In particular, the most stable situation is achieved (in this idealized model) only when each planetary orbit is roughly twice as far from the Sun as the preceding one, as observed empirically already by Titius (1766) and Bode (1778) and used in both the discoveries of Uranus (1781) and the Asteroid Belt (1801). ETC."
'via Blog this'
"In a planetary or satellite system, idealized as n small bodies in initially coplanar, concentric orbits around a large central body, obeying Newtonian point-particle mechanics, resonant perturbations will cause dynamical evolution of the orbital radii except under highly specific mutual relationships, here derived analytically apparently for the first time. In particular, the most stable situation is achieved (in this idealized model) only when each planetary orbit is roughly twice as far from the Sun as the preceding one, as observed empirically already by Titius (1766) and Bode (1778) and used in both the discoveries of Uranus (1781) and the Asteroid Belt (1801). ETC."
'via Blog this'
Saturday, January 4, 2014
Paradigm Shifts
Nevertheless the opportunity was utterly blocked by the scientific paradigm of Laplacian determinism.
From Ivan I. Shevchenko
From Ivan I. Shevchenko
On the Principle of Least Action Interaction (Ovenden)
Springer
The history of the Titius-Bode Law is summarized, and possible explanations for the law are examined. Numerical integrations confirm the intuition that any N-body point-mass planetary system spends most of its time in configurations where the planetary interactions are least. This result is formalized into the Principle of Least Interaction Action, viz. that such a system will most often be found in a configuration where the time-mean of the action associated with the mutual interactions of the planets is a local minimum. It is shown that this principle leads to the resonant structures predicted (by a complementary argument) by Roy and Ovenden (1955), and found in the satellite systems of Jupiter and Saturn. Time-scale estimates show that the time of relaxation from an arbitrary configuration is short compared with the time spent near such a minimum interaction configuration. These results suggest that the present distribution of planetary and satellite orbits is the result of mutual perturbations, that tidal forces need not be invoked, and that the present distribution gives no information concerning the origin of the solar system.
However, if it can be shown that processes operate within the solar system that can rearrange the planetary orbits on a su~iciently short time-scale then we must conclude that the present distribution of planetary and satellite orbits contains no information about conditions at the time of formation of the solar system. The rest of this paper will be devoted to providing evidence that such a process does exist, in the mutual gravitational perturbations of one planet or satellite upon another.
From all these integrations a general characteristic stands out clearly. A system spends a short time with the planets close together and interacting violently, and spends most of its time with the planets far apart and interacting mildly, as is indeed to be expected from the most elementary consideration. We now formalize this elementary consideration into The Principle of Planetary Claustrophobia, namely that, in any system, the planets will spend most of their time as far away from each other as possible.
However, if it can be shown that processes operate within the solar system that can rearrange the planetary orbits on a su~iciently short time-scale then we must conclude that the present distribution of planetary and satellite orbits contains no information about conditions at the time of formation of the solar system. The rest of this paper will be devoted to providing evidence that such a process does exist, in the mutual gravitational perturbations of one planet or satellite upon another.
From all these integrations a general characteristic stands out clearly. A system spends a short time with the planets close together and interacting violently, and spends most of its time with the planets far apart and interacting mildly, as is indeed to be expected from the most elementary consideration. We now formalize this elementary consideration into The Principle of Planetary Claustrophobia, namely that, in any system, the planets will spend most of their time as far away from each other as possible.
Friday, January 3, 2014
Titius-Bode, Poveda and Rabinowitz
My friend Mario Rabinowitz just revived my interest on this relation, which the Mexican Astronomer Poveda has been studying for many years now.
Arcadio Poveda visited us at the Physics school of the University of Puebla (UAP) many years ago. Tapan Kumar Chatterjee invited him, when Dr. Chatterjee was a professor there. Poveda has been an original astronomer, and I have followed his work. Recently Dr. Poveda analyzed extra-solar planetary systems with the so-called Titius-Bode Law, which Rabinowitz told me was discovered by Johann Daniel Titius.
I believe that they are bound to be regularities for objects moving close to a plane, because they exert forces on each other. This is a formation issue, that likely requires computer calculations to derive. The main idea though, is that a planar many body problem follows regularities, as has been observed by the hexagonal structure in Jupiter. From those hexagons to some radius relation for planetary orbits, I just see computer work directed to finding it. One planet, pulling a nearby one, competing with other planets on the other side of the orbit, could produce an orbit, not too close, and not too far, like in the Goldilocks fairy tale. Order out of Chaos.
Arcadio Poveda visited us at the Physics school of the University of Puebla (UAP) many years ago. Tapan Kumar Chatterjee invited him, when Dr. Chatterjee was a professor there. Poveda has been an original astronomer, and I have followed his work. Recently Dr. Poveda analyzed extra-solar planetary systems with the so-called Titius-Bode Law, which Rabinowitz told me was discovered by Johann Daniel Titius.
I believe that they are bound to be regularities for objects moving close to a plane, because they exert forces on each other. This is a formation issue, that likely requires computer calculations to derive. The main idea though, is that a planar many body problem follows regularities, as has been observed by the hexagonal structure in Jupiter. From those hexagons to some radius relation for planetary orbits, I just see computer work directed to finding it. One planet, pulling a nearby one, competing with other planets on the other side of the orbit, could produce an orbit, not too close, and not too far, like in the Goldilocks fairy tale. Order out of Chaos.
Exoplanet Predictions Based on the Generalised Titius-Bode Relation
Jonathan Swift and the Moons of Mars
They have likewise discovered two lesser stars, or satellites, which revolve about Mars; whereof the innermost is distant from the centre of the primary planet exactly three of his diameters, and the outermost, five; the former revolves in the space of ten hours, and the latter in twenty-one and a half; so that the squares of their periodical times are very near in the same proportion with the cubes of their distance from the centre of Mars; which evidently shows them to be governed by the same law of gravitation that influences the other heavenly bodies.
Gulliver's Travels
Gulliver's Travels
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