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Computer performance analysis - Measurement objectives and tools
Objectives and measurements in computer performance analysi
The Relativistically Spinning Charged Sphere
When the equatorial spin velocity, , of a charged conducting sphere
approaches , the Lorentz force causes a remarkable rearrangement of the
total charge .
Charge of that sign is confined to a narrow equatorial belt at latitudes while charge of the opposite sign
occupies most of the sphere's surface. The change in field structure is shown
to be a growing contribution of the `magic' electromagnetic field of the
charged Kerr-Newman black hole with Newton's G set to zero. The total charge
within the narrow equatorial belt grows as and tends to
infinity as approaches . The electromagnetic field, Poynting vector,
field angular momentum and field energy are calculated for these
configurations.
Gyromagnetic ratio, g-factor and electromagnetic mass are illustrated in
terms of a 19th Century electron model. Classical models with no spin had the
small classical electron radius a hundredth of the Compton
wavelength, but models with spin take that larger size but are so
relativistically concentrated to the equator that most of their mass is
electromagnetic.
The method of images at inverse points of the sphere is shown to extend to
charges at points with imaginary co-ordinates.Comment: 15 pages, 1figur
Fine-grained uncertainty relation and nonlocality of tripartite systems
The upper bound of the fine-grained uncertainty relation is different for
classical physics, quantum physics and no-signaling theories with maximal
nonlocality (supper quantum correlation), as was shown in the case of bipartite
systems [J. Oppenheim and S. Wehner, Science 330, 1072 (2010)]. Here, we extend
the fine-grained uncertainty relation to the case of tripartite systems. We
show that the fine-grained uncertainty relation determines the nonlocality of
tripartite systems as manifested by the Svetlichny inequality, discriminating
between classical physics, quantum physics and super quantum correlations.Comment: 4 page
A Detail in Kronecker's Program
It was Kronecker who sought to avoid the use in mathematics of all numbers (negatives, fractions, irrationals) other than the positive integers, and he outlined the means for carrying through this program. In the introductory sections of his memoir he briefly indicates the personal philosophy which made such a project appear desirable
Bell's theorem as a signature of nonlocality: a classical counterexample
For a system composed of two particles Bell's theorem asserts that averages
of physical quantities determined from local variables must conform to a family
of inequalities. In this work we show that a classical model containing a local
probabilistic interaction in the measurement process can lead to a violation of
the Bell inequalities. We first introduce two-particle phase-space
distributions in classical mechanics constructed to be the analogs of quantum
mechanical angular momentum eigenstates. These distributions are then employed
in four schemes characterized by different types of detectors measuring the
angular momenta. When the model includes an interaction between the detector
and the measured particle leading to ensemble dependencies, the relevant Bell
inequalities are violated if total angular momentum is required to be
conserved. The violation is explained by identifying assumptions made in the
derivation of Bell's theorem that are not fulfilled by the model. These
assumptions will be argued to be too restrictive to see in the violation of the
Bell inequalities a faithful signature of nonlocality.Comment: Extended manuscript. Significant change
Electromagnetic Magic: The Relativistically Rotating Disk
A closed form analytic solution is found for the electromagnetic field of the
charged uniformly rotating conducting disk for all values of the tip speed
up to . For it becomes the Magic field of the Kerr-Newman black hole
with set to zero.
The field energy, field angular momentum and gyromagnetic ratio are
calculated and compared with those of the electron.
A new mathematical expression that sums products of 3 Legendre functions each
of a different argument, is demonstrated.Comment: 10 pages, one figur
Relativistic Poynting Jets from Accretion Disks
A model is developed for relativistic Poynting jets from the inner region of
a disk around a rotating black hole. The disk is initially threaded by a
dipole-like magnetic field. The model is derived from the special relativistic
equation for a force-free electromagnetic field. The ``head'' of the Poynting
jet is found to propagate outward with a velocity which may be relativistic.
The Lorentz factor of the head (Gamma) is found to be dependent on the magnetic
field strength close to the black hole, B_0, the density of the external medium
n_ext, and on the ratio R=r_0/r_g >1, where r_g is the gravitational radius of
the black hole, and r_0 is the radius of the O-point of the initial dipole
field threading the disk. For conditions pertinent to an active galactic
nuclei, Gamma is approximately equal to 8 (10/R)^(1/3) (B_0/10^3 Gauss)^(1/3)
(1/cm^3/n_ext)^(1/6). This model offers an explanation for the observed Lorentz
factors which are of the order of 10 for the parsec-scale radio jets measured
with very long baseline interferometry.Comment: 4 pages, 1 figur
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