On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:





On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

On 19 Oct, 00:27, maxwell <s...@shaw.ca> wrote:



On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:

On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

Yes, I am doing this. My crude derivation is further up the thread,
but I'll repeat it here:-
Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

The total potential is then q2/r2 + q1/(r2 + dr(1 + B)) which for
small dr and q1 = q2 can be written:

q/r2 + q/r2 (1 - dr(1 + B)/r2)

= 2q/r2 - q dr(1 + B)/r2^2 )

I'm not sure how to proceed further, since I was hoping to end up with
an expression 2q/(1 + B) r2. Maybe I've made an error some where...

On Oct 22, 1:47 pm, blackhead <larryhar...@softhome.net> wrote:





On 19 Oct, 00:27, maxwell <s...@shaw.ca> wrote:

On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:

On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

Yes, I am doing this. My crude derivation is further up the thread,
but I'll repeat it here:-
Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

The total potential is then q2/r2 + q1/(r2 + dr(1 + B)) which for
small dr and q1 = q2 can be written:

q/r2 + q/r2 (1 - dr(1 + B)/r2)

= 2q/r2 - q dr(1 + B)/r2^2 )

I'm not sure how to proceed further, since I was hoping to end up with
an expression 2q/(1 + B) r2. Maybe I've made an error some where...

I see. You are offering a dipole model for a point particle; not
quite what I was expecting.

If your two charges have the same sign
how do you keep them at the same distance apart as they move, don't
'like' charges always repel?

It seems you have reduced L-W's charge-density 'cloud' to only two
raindrops.
I was asking for a proof that BEGAN with a single point charge, not
some limiting process which is how all classical EM tries to link to
the real world of electrons.- Hide quoted text -

Page 262, Classical Electromagnetic Radiation by Head Marion, gives
Jefimenko's equations and states:

"These generalised formulas make clear that, fundamentally, it is
charges and currents (moving charges) that produce electric and
magnetic fields."

Then further down they say:

"From this view, neither field can cause the other (any more than one
component of E can cause another component). Rather BOTH fields are
cause by charges and currents"

On page 428 ofIntroduction to Electrodynamics by Griffiths, he derives
Jefimenko's equations and states them as being the "Causual" solution
to Maxwell's equations.

Out of curiosity, could you please supply the publication dates of those
texts?

Classical Electromagnetic Radiation by Head Marion published 1994.

Introduction to Electrodynamics (3rd Edition) by David J.Griffiths
published 1998.

On 23 Oct, 17:12, maxwell <s...@shaw.ca> wrote:



On Oct 22, 1:47 pm, blackhead <larryhar...@softhome.net> wrote:

On 19 Oct, 00:27, maxwell <s...@shaw.ca> wrote:

On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:

On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

Yes, I am doing this. My crude derivation is further up the thread,
but I'll repeat it here:-
Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

The total potential is then q2/r2 + q1/(r2 + dr(1 + B)) which for
small dr and q1 = q2 can be written:

q/r2 + q/r2 (1 - dr(1 + B)/r2)

= 2q/r2 - q dr(1 + B)/r2^2 )

I'm not sure how to proceed further, since I was hoping to end up with
an expression 2q/(1 + B) r2. Maybe I've made an error some where...

I see. You are offering a dipole model for a point particle; not
quite what I was expecting.

It's not a model for a point particle, just used to show that in the
limiting process as the point charges approach one another, the
retardation factor is still there and doesn't tend to zero. From this,
it follows that the retardation factor will be there for a point
charge also.

If your two charges have the same sign
how do you keep them at the same distance apart as they move, don't
'like' charges always repel?

Yes, they will repel, as will a charge density of finite volume. You
can add a force that keeps the charges together, it's just superfluous
to the purpose of the derivation.

It seems you have reduced L-W's charge-density 'cloud' to only two
raindrops.
I was asking for a proof that BEGAN with a single point charge, not
some limiting process which is how all classical EM tries to link to
the real world of electrons.- Hide quoted text -

I ...

read more »

On Oct 23, 10:07 am, blackhead <larryhar...@softhome.net> wrote:

On 23 Oct, 17:12, maxwell <s...@shaw.ca> wrote:

On Oct 22, 1:47 pm, blackhead <larryhar...@softhome.net> wrote:

On 19 Oct, 00:27, maxwell <s...@shaw.ca> wrote:

On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:

On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt....@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

Yes, I am doing this. My crude derivation is further up the thread,
but I'll repeat it here:-
Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

The total potential is then q2/r2 + q1/(r2 + dr(1 + B)) which for
small dr and q1 = q2 can be written:

q/r2 + q/r2 (1 - dr(1 + B)/r2)

= 2q/r2 - q dr(1 + B)/r2^2 )

I'm not sure how to proceed further, since I was hoping to end up with
an expression 2q/(1 + B) r2. Maybe I've made an error some where...

I see. You are offering a dipole model for a point particle; not
quite what I was expecting.

It's not a model for a point particle, just used to show that in the
limiting process as the point charges approach one another, the
retardation factor is still there and doesn't tend to zero. From this,
it follows that the retardation factor will be there for a point
charge also.

If your two charges have the same sign
how do you keep them at the same distance apart as they move, don't
'like' charges always repel?

Yes, they will repel, as will a charge density of finite volume. You
can add a force that keeps the charges together, it's just superfluous
to the purpose of the derivation.

It seems you have reduced L-W's charge-density 'cloud' to only two
raindrops.
I was asking for a proof that BEGAN with a single point charge, not
some limiting process which is how all classical EM tries to link to
the real world of electrons.- Hide quoted text -

I ...

read more »

Nice try, but ONE never equals TWO, that would just blow math right
out the window. As I said earlier, all these results reflect the
continuum charge-density model of electricity that is now the basis
for classical EM but this does not reflect reality (and I am not even
bringing in quantum effects!). It is this attempt to preserve the use
of continuum mathematics (the differential calculus) in EM that forced
St Albert to invent special relativity.

On 24 Oct, 19:25, maxwell <s...@shaw.ca> wrote:

On Oct 23, 10:07 am, blackhead <larryhar...@softhome.net> wrote:

On 23 Oct, 17:12, maxwell <s...@shaw.ca> wrote:

On Oct 22, 1:47 pm, blackhead <larryhar...@softhome.net> wrote:

On 19 Oct, 00:27, maxwell <s...@shaw.ca> wrote:

On Oct 13, 9:21 am, blackhead <larryhar...@softhome.net> wrote:

On 13 Oct, 16:39, maxwell <s...@shaw.ca> wrote:

On Oct 12, 4:23 pm, blackhead <larryhar...@softhome.net> wrote:

On 10 Oct, 20:01, maxwell <s...@shaw.ca> wrote:

On Oct 9, 7:04 pm, blackhead <larryhar...@softhome.net> wrote:

On 9 Oct, 21:21, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:

"blackhead" <larryhar...@softhome.net> wrote in message

news:1191608697.381957.118940@w3g2000hsg.googlegroups.com...

On Sep 27, 8:38 pm, "Bill Miller" <billmillerkt....@worldnet.att.net
wrote:
Hell "Mr. E"... Please see below...

"Mr. Entropy" <egi...@yahoo.com> wrote in message

news:1190920163.750141.255400@y42g2000hsy.googlegroups.com...

Hi, Bill

On Sep 26, 5:40 pm, "Bill Miller" <billmillerkt...@worldnet.att.net
wrote:
Its intensity is proportional to the rate of change of current flow
and
inversely proportional to r (distance) and to cSQR. It is equal to the
negative time derivative of A, the magnetic vector potential. or,
Ek= -dA/dt.

Yes, that's exactly what I was thinking. But that would mean that
Gauss' law, which fails to distinguish E from Ek, is incorrect in the
presence of varying currents. If that's true, wouldn't it be common
knowledge by now?

Up 'til now it has been masked by at least three issues. The first is the
idea that an E field can *cause* an H field. The second is that an H
field
can *cause* an E field. The third is Lentz's law.

The first has been proven empirically false since no one has ever been
able
to measure the Magnetic field "caused" by Displacement Current.

The second has been masked by the assumption that induction is a
magnetic
effect when it is an interaction between the movement of charges as
manifested by Ek.

The third has been *ignored*. This is Lentz's law, an interactive
property
that has remained unexplained/unexplainable since it was determined
empirically way back when. The equations that define Ek show how and why
Lentz's law "works" the way it does.

I haven't read Jefimenko's work, but I've come to the conclusion that
E of a charge moving in a charge distribution acts upon that
distribution which in turn acts back on the charge so creating an E
with components parallel and normal to the charge's motion. That which
is normal to the charge's motion is interpteted as the B component
because it does no work, that which is parallel is the E component
because it does work. Is this similar to what Jefimenko has in mind?

Nope...

Jefimenko's proposition is that Maxwell's equations are descriptive; not
causative. He maintains Maxwell's independent definitions of E and H and
assumes their properties are pretty much the same as has always been
postulated.

He shows that their causes are charges and the motion of charges. Since both
E and H have the same root causes, this is why a time varying E is always
associated with a time varying H, and vice-versa.

Unfortunately, Jefimenko's work is "equation rich" and no one (that I know
of) has published any simplified versions with diagrams etc.

The only other place to which I can point you would be Wikepedia. Search for
"Jefimenko's Equations." This will at least show you the structure and
layout of the equations.

I hope this helps!

Bill

His equations don't look as useful as the Lienard-Wiechert potentials
or E and B for a moving charge.

I hope this helps. There's lots more, and that's why I was "ragging" on
Benj. Much of the "stuff" that he (and I) are interested in is covered by
Jefimenko's work.

Thanks much for the reference,

You're welcome!

Bill

Mr. E- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Well put, Bill. It's hard to get people to think about the physics
when they are only examined on the math.
The L-W potentials are derived using a 'small' volume filled with
electric fluid (popularly known as 'charge density'). The 'back' of
this volume reacts to the 'target' (field) point at a slightly
different time than the 'front', hence the retarded factor.

Who's point are you answering?

The back of the charge reacting to the observation point is just plain
stupid.

There is a retarded factor because the contributions to the potential
at an observation point for charges moving are different compared to
if the charges were static but at the same positions.

Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

Finally
the limit is taken of shrinking the volume to zero for a 'point'
charge. Good luck trying to derive this result, ab initio, from the
defininition of a real point-particle, with no finite size, like the
electron.- Hide quoted text -

Yes, the factor is still there as the size tends towards zero for an
electron.

- Show quoted text -

Please learn to read. I wrote "ab initio" not "tends towards zero".
This was my point that Maxwellian EM is based on extended charge
definitions not point charges; ah well, they just don't teach Latin
anymore.- Hide quoted text -

- Show quoted text -

My derivation used 2 point charges to show that the (1 + B) factor is
independent of their seperation, dr. I didn't use extended charges.

Still awaiting your derivation. All derivations of L-W I have seen
use a finite separation to generate a factor from the difference in
transmission times,
Is this what you have done?- Hide quoted text -

- Show quoted text -

Yes, I am doing this. My crude derivation is further up the thread,
but I'll repeat it here:-
Take two charges q1 @r1, q2 @r2 with r1 > r2, dr = r1 - r2, parallel
and both travelling at velocity v away from and along r1, r2. The
observation point is at r = 0. The potential of q1 that arrives at q2
is from a retarded time t' = dr/(v + c). This is when q1 was at r2 +
dr - vt' = r2 + dr - v dr/(v + c) = r2 + dr/(1 + B) where B = v/c. So
the potential at the observation point can be replaced by an
equivalent static q1 and q2 seperated by dr/(1 + B), equivalent to
increasing the charge density by (1 + B) at r.

The total potential is then q2/r2 + q1/(r2 + dr(1 + B)) which for
small dr and q1 = q2 can be written:

q/r2 + q/r2 (1 - dr(1 + B)/r2)

= 2q/r2 - q dr(1 + B)/r2^2 )

I'm not sure how to proceed further, since I was hoping to end up with
an expression 2q/(1 + B) r2. Maybe I've made an error some where....

I see. You are offering a dipole model for a point particle; not
quite what I was expecting.

It's not a model for a point particle, just used to show that in the
limiting process as the point charges approach one another, the
retardation factor is still there and doesn't tend to zero. From this,
it follows that the retardation factor will be there for a point
charge also.

If your two charges have the same sign
how do you keep them at the same distance apart as they move, don't
'like' charges always repel?

Yes, they will repel, as will a charge density of finite volume. You
can add a force that keeps the charges together, it's just superfluous
to the purpose of the derivation.

It seems you have reduced L-W's charge-density 'cloud' to only two
raindrops.
I was asking for a proof that BEGAN with a single point charge, not
some limiting process which is how all classical EM tries to link to
the real world of electrons.- Hide quoted text -

I ...

read more »

Nice try, but ONE never equals TWO, that would just blow math right
out the window. As I said earlier, all these results reflect the
continuum charge-density model of electricity that is now the basis
for classical EM but this does not reflect reality (and I am not even
bringing in quantum effects!). It is this attempt to preserve the use
of continuum mathematics (the differential calculus) in EM that forced
St Albert to invent special relativity.

One does not equal two, but two discrete charges still doesn't
constitute a continum.

Einstein at the very start of his "On the Electrodynamics of Moving
Bodies" paper states:

"It is known that Maxwell's electrodynamics--as usually understood at
the present time--when applied to moving bodies, leads to asymmetries
which do not appear to be inherent in the phenomena. Take, for
example, the reciprocal electrodynamic action of a magnet and a
conductor. The observable phenomenon here depends only on the relative
motion of the conductor and the magnet, whereas the customary view
draws a sharp distinction between the two cases in which either the
one or the other of these bodies is in motion."

And further on says:

"Examples of this sort, together with the unsuccessful attempts to
discover any motion of the earth relatively to the ``light medium,''
suggest that the phenomena of electrodynamics as well as of mechanics
possess no properties corresponding to the idea of absolute rest."

And then states the two postulates of Special Relativity:

"We will raise this conjecture (the purport of which will hereafter be
called the ``Principle of Relativity'') to the status of a postulate,
and also introduce another postulate, which is only apparently
irreconcilable with the former, namely, that light is always
propagated in empty space with a definite velocity c which is
independent of the state of motion of the emitting body."

Based on this introduction, don't you think the correct conclusion is
that he extended Gallilean Relativity to include optics?

I haven't come across this idea that he introduced Relativity to
preserve the use of the differential calculus in EM theory, so would
be interested in any evidence to back up your claim.

Larry.

El Snippo





Page 262, Classical Electromagnetic Radiation by Head Marion, gives
Jefimenko's equations and states:

"These generalised formulas make clear that, fundamentally, it is
charges and currents (moving charges) that produce electric and
magnetic fields."

Then further down they say:

"From this view, neither field can cause the other (any more than one
component of E can cause another component). Rather BOTH fields are
cause by charges and currents"

On page 428 ofIntroduction to Electrodynamics by Griffiths, he derives
Jefimenko's equations and states them as being the "Causual" solution
to Maxwell's equations.

Out of curiosity, could you please supply the publication dates of those
texts?

Classical Electromagnetic Radiation by Head Marion published 1994.

Introduction to Electrodynamics (3rd Edition) by David J.Griffiths
published 1998.

Thanks! Do either of these texts also re-derive/define the Poynting Vector
using Jefimenko's Equations? If so, I'd sure love to see it!

Bill Miller- Hide quoted text -

- Show quoted text -