Regarding Beagle,
The disclaimer on my homepage obviously refers to the five essays posted each week and the 20 previous essays toward the bottom. Would you apply said statement to BlackICE Defender? It is a superb, inexpensive, set-and-forget firewall for anybody connected to the Net. BTW, Outrageous On-Line Uncle Al was hit three times by the Clinton administration. Clinton is now in Harlem and Uncle Al is still on the Web.
Regading Ethic,
You don’t grasp the difference between chirality and parity. Chirality is a mirror-image (one coordinate axis inverted) that is not superposable upon the original. A chiral object or array may not contain Sn improper rotation axes as symmetry elements - no inversion point (S2), reflection planes (S1), or higher Sn (a baseball seam is S4). Parity is inversion of all three coordinate axes with the same symmetry constraints. All parity pairs are chiral. Not all chiral objects are parity pairs.
http://www.mazepath.com/uncleal/invert.gif
A mirror-imaged achiral space group is the same space group. A mirror-imaged chiral (but not parity) space group is the same space group. An inverted parity space group is a different space group. Parity is a more rigorous constraint - a restricted subset - than mere chirality.
Chirality of single points or particles (axial vector) is distinct from chirality of a 3-space array. Different maths, different physical requirements.
Regarding Truth Seeker,
Helicity, chirality, and parity are distinct maths. Parity of a point is not the same math as parity of an array subtending volume. In Creative Writing or wine tasting you can emit any words you please and endow them with any random meanings the mob will swallow. Everything and its opposite are true; local reality is subject to majority vote. This does not occur in the sciences. Meanings are objective and truth is empirical black and white. There is no vote.
The helicity of a vector field defined on a domain in 3-space, introduced by Woltjer in 1958 and named by Moffatt in 1969, is the standard measure of the extent to which the field lines wrap and coil around one another. It plays important roles in fluid mechanics, magnetohydrodynamics and plasma physics.
Regarding Beagle again,
If parity pair single crystals of tellurium obey the Equivalence Principle (EP), they will sit at opposite sides of an Eotvos balance rotor suspended from a fiber 1/10 the thickenss of a human air and fall identically - pursue parallel minimum action trajectories - around the sun as they spin with the Earth day to night to day. There will be no torque exerted. Everything will sit there. (The Earth’s gravity and gravitation per se are inert in the experiment.)
If they violate the EP they will fall in non-parallel minimum action trajectories. One test mass will fall “sideways” relative to the other by about one part in a trillion. They will have slightly different orbits around the sun. (Anything bigger violates other things.) As the two masses pursue slightly non-parallel paths there will be a varying torque exerted on the rotor. (Torque varies as the phase angle between inertial acceleration of Earth’s spin and gravitational acceleration of free-fall around the sun). The rotor will twist on its fiber ever so slighty until counter-torque from the elastically deformed fiber pushes back in balance. The maximum peripheral rotor movement is the width of an atom or so. There is a mirror attached to the rotor that forms one leg of an interferometer. As the mirror moves about an atom’s diameter there will be detected a fringe shift in the interferometer’s output. The system starts exactly nulled. Any fringe shift will leak photons into the detector. As we can reliably detect single photons… and the optical lever arm balance rotor to detector is meters long… there is a lot of gain given the signal starting from a very small physical movement. Random thermal vibration of the rotor’s own atoms is a major source of noise.
Regarding JS Princeton,
Only massed parity systems are a parity test of the EP. Diddling massless photon 4-momentum requires other properties:
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The Sagnac effect in ring laser gyroscopes is a spacetime topological probe proportional to the scalar product of area and angular velocity vectors, and inversely to perimeter length (proportional to subtended area and compactness).
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The Aharonov-Bohm (magnetic) and Aharonov-Casher (charge) effects are also areal - Electromagnetic potentials, rather than the electric and magnetic fields, are the fundamental quantities in quantum mechanics. Gravity is not an electromagnetic phenomenon. Photon polarization doesn’t care about gravitation.
Class. Quantum Grav. 17 4125-4157 (2000)
It is possible to obtain exactly the Maxwell equations from the Einstein field equation, but there is a long list of caveats that inevitably breaks the analogy with electromagnetism.
The source of monopole radiation is a changing monopole moment for a charge q or for a mass m. Since charge and mass are conserved, there can be neither monopole electromagnetic radiation nor monopole gravitational radiation.
The source of dipole radiation is a changing dipole moment. (Punctiliously, you need a second time derivative of the dipole moment.) For a pair of charges
d = qr + q’r’
and there’s nothing special about the derivatives. For a pair of masses, the gravitational dipole moment is
d = mr + m’r’
and its time derivative is
mv + m’v’ = p + p’
By conservation of momentum the second time derivative of the gravitational dipole moment is zero, and you can go to a center of momentum frame and set the first derivative to zero as well. There is no gravitational “electric dipole” radiation.
Consider the analog of “magnetic dipole” radiation. The gravitational equivalent of the magnetic dipole moment for a pair of charges is
M = mv x r + m’v’ x r’
(“x” is the cross product, “mv” is the “mass current”)
But M is the total angular momentum, which is also conserved. There is no gravitational “magnetic dipole” radiation.
The next moment up is quadrupole, with no relevant conservation laws, so gravitational quadrupole radiation is permitted. You
can use this argument to advocate that gravity must be a tensorial (spin-2) interaction. Electromagnetism is mediated by spin-1 photons.
Photon polarization doesn’t care about gravitation.
–
Uncle Al
http://www.mazepath.com/uncleal/eotvos.htm
(Do something naughty to physics)