Moving streams of matter should produce a "Gravitomagnetic field" analogous to the magnetic field from moving charges. This is orthodox GR, even if some details are in contention. (See for example, http://en.wikipedia.org/wiki/Gravitomagnetism.)

I played around with equivalent matter streams moving in opposite directions. That should cancel out their gravitomagnetic fields B* (usually just called "B" after context given), but I found an inconsistency. The problem was, superposition of B* from two sources as if a vector field did not work. (Sure, gravity is more complicated, but that part should approximate vector fields and emulate EM at low mass levels - ? - and I expect even non-linear superpositions to cancel out opposite fields.) For example, let's have adjacent streams going 0.5c in opposite directions, very low mass density to provide high expected linearity (albeit at relativistic speeds.) The proper value of g seen in our frame K is gamma squared times the value g_s at rest relative to either single stream (hence g = 2gamma^2(0.5c)g_s = (2*4/3)g_s = (8/3)g_s), due to the multiplied effects of Lorentz contraction and greater relativistic mass-energy density (thus field-producing power) per proper length unit in the mass flow.

We will send a unit mass M moving at 0.5c, frame K', along the streams' path, in either direction. We, expecting to see only "g" since the B* has ostensibly been canceled, expect M to experience gamma squared the value of proper acceleration towards the stream that we find in K (lateral acceleration transformation, from shorter proper time to fall.) Since effective mass-energy of M is gamma*M_0 (one of the cases where "relativistic mass" is still relevant), that is equivalent to a force in K increased to gamma times rest value and thus in K', gamma squared times the force in K (due to force transformation.) Hence by that consistent-seeming reckoning, the acceleration of M in K' should be gamma^2(0.5c)g = 2gamma^4(0.5c)g_s = (32/9)g_s.

However, in M's frame, one stream is at rest and the other one goes at 0.8c. The combined effect is therefore [1 + gamma^2(0.8c)]g_s = (34/9)g_s =(17/16)*(32/9)g_s. It is easy to verify (using the additive gamma factor being gamma(v1 + v2) = gamma1*gamma2*(1 + v1*v2/c^2)) that the ratio in general of the second prediction to the first is (1 + v^4/c^4).

That is an odd contradiction, and I just don't know what to make of it. Sure, gravitation is not like EM and with curved space etc., but would anyone expect low-gravity fields of any kind not to cancel out if apparently of opposite sign? Has anyone found good rules for B*? Has this issue been talked about before, and where? Thanks.

On Nov 15, 3:43 pm, "Neil Bates" wrote:
Moving streams of matter should produce a "Gravitomagnetic field" analogous to the magnetic field from moving charges. This is orthodox GR, even if some details are in contention. (See for example,http://en.wikipedia.org/wiki/Gravitomagnetism.)

I played around with equivalent matter streams moving in opposite directions. That should cancel out their gravitomagnetic fields B* (usually just called "B" after context given), but I found an inconsistency. The problem was, superposition of B* from two sources as if a vector field did not work. (Sure, gravity is more complicated, but that part should approximate vector fields and emulate EM at low mass levels - ? - and I expect even non-linear superpositions to cancel out opposite fields.) For example, let's have adjacent streams going 0.5c in opposite directions, very low mass density to provide high expected linearity (albeit at relativistic speeds.) The proper value of g seen in our frame K is gamma squared times the value g_s at rest relative to either single stream (hence g = 2gamma^2(0.5c)g_s = (2*4/3)g_s = (8/3)g_s), due to the multiplied effects of Lorentz contraction and greater relativistic mass-energy density (thus field-producing power) per proper length unit in the mass flow.

We will send a unit mass M moving at 0.5c, frame K', along the streams' path, in either direction. We, expecting to see only "g" since the B* has ostensibly been canceled, expect M to experience gamma squared the value of proper acceleration towards the stream that we find in K (lateral acceleration transformation, from shorter proper time to fall.) Since effective mass-energy of M is gamma*M_0 (one of the cases where "relativistic mass" is still relevant), that is equivalent to a force in K increased to gamma times rest value and thus in K', gamma squared times the force in K (due to force transformation.) Hence by that consistent-seeming reckoning, the acceleration of M in K' should be gamma^2(0.5c)g = 2gamma^4(0.5c)g_s = (32/9)g_s.

However, in M's frame, one stream is at rest and the other one goes at 0.8c. The combined effect is therefore [1 + gamma^2(0.8c)]g_s = (34/9)g_s =(17/16)*(32/9)g_s. It is easy to verify (using the additive gamma factor being gamma(v1 + v2) = gamma1*gamma2*(1 + v1*v2/c^2)) that the ratio in general of the second prediction to the first is (1 + v^4/c^4).

That is an odd contradiction, and I just don't know what to make of it. Sure, gravitation is not like EM and with curved space etc., but would anyone expect low-gravity fields of any kind not to cancel out if apparently of opposite sign? Has anyone found good rules for B*? Has this issue been talked about before, and where? Thanks.

For simplicity, Maxwell's equations assume a axis of
symmetry that may not always exist. That is why inertial
coupling is through mass/energy equivalence in GR.

The ewald method allows the consideration of
induction components aren't symetrical

http://www.research.ibm.com/grape/grape_ewald.htm

Einstein published his theory of
gravitation, or general theory of relativity,
in 1916. And so a new paradigm, or set of
beliefs, was established. It was not until
1930 that Fritz London explained the weak,
attractive dipolar electric bonding force
(known as Van der Waals' dispersion force
or the 'London force') that causes gas
molecules to condense and form liquids
and solids. Like gravity, the London force
is always attractive and operates between
electrically neutral molecules

What a different story might have been told
if London's insight had come a few decades
earlier? Physics could, by now, have advanced
by a century instead of being bogged in a
mire of metaphysics.
http://www.holoscience.com/news.php?article=r4k29syp

GP-B
http://einstein.stanford.edu/

Tajmar / de Matos
http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html

Sue...

"Neil Bates" wrote in message
...
"...It is easy to verify (using the additive gamma factor being gamma(v1 +
v2) = gamma1*gamma2*(1 + v1*v2/c^2)) that the ratio in general of the second
prediction to the first is (1 + v^4/c^4)."

I mean, relativistic velocity addition for gamma(v1 + v2), but don't have a
good symbol to use (the oft-used dot on top of plus is real hard to find in
fonts.)

On Nov 15, 4:55 pm, "Neil Bates" wrote:
"Neil Bates" wrote in message

...
"...It is easy to verify (using the additive gamma factor being gamma(v1 +
v2) = gamma1*gamma2*(1 + v1*v2/c^2)) that the ratio in general of the second
prediction to the first is (1 + v^4/c^4)."

I mean, relativistic velocity addition for gamma(v1 + v2), but don't have a
good symbol to use (the oft-used dot on top of plus is real hard to find in
fonts.)

It sounds like you might be using Purcell's circular
derivation for magnetism.
http://physics.weber.edu/schroeder/mrr/MRRtalk.html

Something that actually uses superpositon would be
better.


http://en.wikipedia.org/wiki/Multipl...l_applications
Time-independent Maxwell equations
Time-dependent Maxwell's equations
http://farside.ph.utexas.edu/teachin.../lectures.html

....tho the problems with the Lorenz gauge will still exist.

Sue...

On Nov 15, 3:43 pm, "Neil Bates" wrote:

That is an odd contradiction, and I just don't know what to make of it. Sure, gravitation is not like EM and with curved space etc., but would anyone expect low-gravity fields of any kind not to cancel out if apparently of opposite sign? Has anyone found good rules for B*? Has this issue been talked about before, and where? Thanks.

Just a word on terminology. I have in a discussion heard the
gravitomagnetic field referred to as a Thirring field. I don't know
how common that term is, but maybe it is better than the term
gravitomagnetic field.
Thirring analyzed space time curvature around a rotating mass.
This space-time curvature is analogous to the gravitomagnetic field.
So the word Thirring field may be appropriate.

I think the main difference between the Maxwell-analog gravity
and the full GR gravity is the kinematic effect of gravity on rulers
and clocks. There is no analog in a strong electric field as described
by Maxwell's equations to the slowing down of time in a strong
gravitational field predicted by GR. So Maxwell-analog gravity is not
exactly the same as GR gravity.
One difference: in Maxwell's equations, there are only two
polarizations of the free-space electromagnetic wave. So in Maxwell-
analog gravity, there are only two polarizations of gravity waves. One
can think of the two polarizations as transverse horizontal and
transverse vertical. In GR gravity, there are four polarizations of
the free-space gravitational wave. There is transverse horizontal,
transverse vertical, longitudinal, and torsional. This is true even
for small amplitude gravity waves (i.e., low gravity).
So I suspect in your case that the Thirring field is not exactly
pointing in the direction you think it is pointing. The extra two
polarizations are producing a Thirring field component which isn't
canceling out.

Maxwell's equations stem from a scaler potential Quad^2ö = p Where p
is a charge density. Quad^2 is the four dimensional analogue of the
"Del" operator. ö is a scalar quantity.

Gravitational waves on the other hand involve tensors and NOT scalars.
This is where the confusion takes place. Gravitational waves are
quadripolar and not diploar. They have 5 planes of polarization and
gravitational fileds can be along the direction of motion.. In
elementary particle physics we say that a graviton is a boson with
spin 2. The photon has a spin of 1.

There are in fact GR codes which will give a finite element solution.
These tell us what happens when matter approached a spinning black
hole for example.


- Ian Parker

On Nov 15, 3:43 pm, "Neil Bates" wrote:
Moving streams of matter should produce a "Gravitomagnetic field" analogous to the magnetic field from moving charges. This is orthodox GR, even if some details are in contention. (See for example,http://en.wikipedia.org/wiki/Gravitomagnetism.)

I played around with equivalent matter streams moving in opposite directions. That should cancel out their gravitomagnetic fields B* (usually just called "B" after context given), but I found an inconsistency. The problem was, superposition of B* from two sources as if a vector field did not work. (Sure, gravity is more complicated, but that part should approximate vector fields and emulate EM at low mass levels - ? - and I expect even non-linear superpositions to cancel out opposite fields.) For example, let's have adjacent streams going 0.5c in opposite directions, very low mass density to provide high expected linearity (albeit at relativistic speeds.) The proper value of g seen in our frame K is gamma squared times the value g_s at rest relative to either single stream (hence g = 2gamma^2(0.5c)g_s = (2*4/3)g_s = (8/3)g_s), due to the multiplied effects of Lorentz contraction and greater relativistic mass-energy density (thus field-producing power) per proper length unit in the mass flow.

We will send a unit mass M moving at 0.5c, frame K', along the streams' path, in either direction. We, expecting to see only "g" since the B* has ostensibly been canceled, expect M to experience gamma squared the value of proper acceleration towards the stream that we find in K (lateral acceleration transformation, from shorter proper time to fall.) Since effective mass-energy of M is gamma*M_0 (one of the cases where "relativistic mass" is still relevant), that is equivalent to a force in K increased to gamma times rest value and thus in K', gamma squared times the force in K (due to force transformation.) Hence by that consistent-seeming reckoning, the acceleration of M in K' should be gamma^2(0.5c)g = 2gamma^4(0.5c)g_s = (32/9)g_s.

However, in M's frame, one stream is at rest and the other one goes at 0.8c. The combined effect is therefore [1 + gamma^2(0.8c)]g_s = (34/9)g_s =(17/16)*(32/9)g_s. It is easy to verify (using the additive gamma factor being gamma(v1 + v2) = gamma1*gamma2*(1 + v1*v2/c^2)) that the ratio in general of the second prediction to the first is (1 + v^4/c^4).

That is an odd contradiction, and I just don't know what to make of it. Sure, gravitation is not like EM and with curved space etc., but would anyone expect low-gravity fields of any kind not to cancel out if apparently of opposite sign? Has anyone found good rules for B*? Has this issue been talked about before, and where? Thanks.


These maxwell type equations are essentially derived from the Kerr
metric for a rotating "point" source. They won't work outside of that
particular context, since without the rotating source, you no longer
have a Kerr-type metric, and hence no gravitomagnetic field.

On Fri, 16 Nov 2007 03:57:09 -0800 (PST), Ian Parker
wrote:

Maxwell's equations stem from a scaler potential Quad^2? = p Where p
is a charge density. Quad^2 is the four dimensional analogue of the
"Del" operator. ? is a scalar quantity.

I find it infinitely better to call the D'Almbertian the "box
operator". I just like saying "box squared".


Gravitational waves on the other hand involve tensors and NOT scalars.
This is where the confusion takes place. Gravitational waves are
quadripolar and not diploar. They have 5 planes of polarization and
gravitational fileds can be along the direction of motion.. In
elementary particle physics we say that a graviton is a boson with
spin 2. The photon has a spin of 1.

*scratches head*

I thought gravitational waves only had two unique polarizations?


There are in fact GR codes which will give a finite element solution.
These tell us what happens when matter approached a spinning black
hole for example.


- Ian Parker

On 16 Nov, 23:31, Eric Gisse wrote:
On Fri, 16 Nov 2007 03:57:09 -0800 (PST), Ian Parker

wrote:
Maxwell's equations stem from a scaler potential Quad^2? = p Where p
is a charge density. Quad^2 is the four dimensional analogue of the
"Del" operator. ? is a scalar quantity.

I find it infinitely better to call the D'Almbertian the "box
operator". I just like saying "box squared".



Gravitational waves on the other hand involve tensors and NOT scalars.
This is where the confusion takes place. Gravitational waves are
quadripolar and not diploar. They have 5 planes of polarization and
gravitational fileds can be along the direction of motion.. In
elementary particle physics we say that a graviton is a boson with
spin 2. The photon has a spin of 1.

*scratches head*

I thought gravitational waves only had two unique polarizations?





There are in fact GR codes which will give a finite element solution.
These tell us what happens when matter approached a spinning black
hole for example.

http://en.wikipedia.org/wiki/Gravitational_waves
http://www.lnl.infn.it/~auriga/auriga/grav_wave.html

Cross and plus are in a plane so each one is counted twice.

These show the planes of polarization. They are totally different from
EM waves. A spin of 2 means 5 quantized states.


- Ian Parker

On Sat, 17 Nov 2007 03:31:49 -0800 (PST), Ian Parker
wrote:

On 16 Nov, 23:31, Eric Gisse wrote:
On Fri, 16 Nov 2007 03:57:09 -0800 (PST), Ian Parker

wrote:
Maxwell's equations stem from a scaler potential Quad^2? = p Where p
is a charge density. Quad^2 is the four dimensional analogue of the
"Del" operator. ? is a scalar quantity.

I find it infinitely better to call the D'Almbertian the "box
operator". I just like saying "box squared".



Gravitational waves on the other hand involve tensors and NOT scalars.
This is where the confusion takes place. Gravitational waves are
quadripolar and not diploar. They have 5 planes of polarization and
gravitational fileds can be along the direction of motion.. In
elementary particle physics we say that a graviton is a boson with
spin 2. The photon has a spin of 1.

*scratches head*

I thought gravitational waves only had two unique polarizations?





There are in fact GR codes which will give a finite element solution.
These tell us what happens when matter approached a spinning black
hole for example.

http://en.wikipedia.org/wiki/Gravitational_waves
http://www.lnl.infn.it/~auriga/auriga/grav_wave.html

Cross and plus are in a plane so each one is counted twice.

These show the planes of polarization. They are totally different from
EM waves. A spin of 2 means 5 quantized states.


- Ian Parker

Which means jack since the notion that the gravition is a spin 2
particle comes from trying to quantize linearized general relativity.