On Saturday, November 27, 2021 at 9:06:29 PM UTC-5, rotchm wrote:
> On Saturday, November 27, 2021 at 3:05:56 PM UTC-5, det...@outlook.com wrote:
> > On Saturday, November 27, 2021 at 12:05:30 PM UTC-6, rotchm wrote:

> > You keep changing things. Here's your original question:
> > "Say, a ray of light passes by you.
> > "It does this every hour or so..., and you have no idea where it comes from.
> > "You decide to measure the speed of this train of rays.
> > "What value(s) you think you will get?"

> Correct. That is what I asked.

> > You have changed it into a LAB experiment where you KNOW where the
> > photons come from,

> No. It clearly states up there that we have no idea where the ray comes from.

No rebuttal? So you agree that you did not understand what you read or that you lied?

> > because YOU CREATE THEM.
>
> Nowhere did I say above I created them.

No rebuttal? So you agree that you did not understand what you read or that you lied?

> We are speaking of a packet of photons. A blip containing many photons. You can trap half of them and the other half moves on and you trap the other half. This is what everybody has been telling you.

No rebuttal?

> You want to measure the speed of a blip. Only one of those blips.
> How would you proceed? What value do you think you will get?

No answer... Are you trapped?

rotchm wrote:

> On Saturday, November 27, 2021 at 9:06:29 PM UTC-5, rotchm wrote:
>> No. It clearly states up there that we have no idea where the ray comes
>> from.
>
> No rebuttal? So you agree that you did not understand what you read or
> that you lied?

go fuck yourself, you stupid know-nothing rebuttal. Nobody is talking
with you. Google will ban you for stupidity, you stinking sack of
subhuman excrement.

On 11/28/2021 12:26 PM, Ed Lake wrote:
> On Sunday, November 28, 2021 at 10:47:25 AM UTC-6, Michael Moroney wrote:
>> On 11/28/2021 10:14 AM, Ed Lake wrote:
>>
>>> A LIDAR GUN can only be operated while stationary because it has no way
>>> to measure its own speed. A "autonomous vehicle" also has a mechanical
>>> speedometer. So, it can measure changes in distance to some obstacle
>>> ahead via LIDAR while also measuring its own speed mechanically.
>> And why couldn't a LIDAR gun detect the Doppler Effect on reflections of
>> its pulses from the road, signs, whatever, to determine the speed of the
>> road relative to itself and do a trivial Galilean shift to determine its
>> own speed relative to the road?
>
> Because the PURPOSE of a LIDAR gun is to be more PRECISE in identifying a
> target than a radar gun. A LIDAR gun has a gun-sight and emits a VERY narrow
> cone of photons so that the operator can pick out a single vehicle on a road
> where there are many other vehicles and just target one of them. That is a
> REAL PROBLEM for radar guns, and it is why hand-held LIDAR guns are
> rapidly replacing RADAR guns. My local police no longer use hand-held
> radar guns. They only use LIDAR guns. Radar is used on vehicle-mounted
> radar guns, because radar can be used while moving.

Not an answer to my question. It would work that way just fine. The only
difference is a cop really can't drive and aim the LIDAR safely at the
same time.

On Sunday, November 28, 2021 at 9:46:57 AM UTC-8, Townes Olson wrote:
> On Sunday, November 28, 2021 at 7:14:18 AM UTC-8, det...@outlook.com wrote:
> >>> A LIDAR GUN can only be operated while stationary because it has no way
> >>> to measure its own speed.
> >>>
> >> Not true. It so happens that most common LIDAR speed guns are of the “stationary” variety, meaning they just send a signal to the target to yield the rate of change of the distance between gun and target, but it’s also possible to create a “moving LIDAR” device that sends two signals, one to the target and one to some background object on the road, and subtract the two, just like “moving radar”.
> >
> > It may be "possible"…
>
> May be? There’s no need to be tentative about it. It not only may be possible, it clearly *is* possible. A simple LIDAR speed gun gives the relative speed between gun and target, it can be pointed at a citizen’s car and then pointed at a road sign (for example), and the difference between the two relative speeds is the speed of the citizen’s car relative to the road sign (taking the cosine effect into account).

How long before you come to realize that Ed is completely unteachable and will NEVER understand even the most basic tenets of relativity? He is a hopeless case and a huge waste of time. I cannot believe that he continues to have hundreds of responses to his idiotic posts... and the material covered is always the same, over and over and over again... he cannot even understand how a simple radar gun works!

On 11/28/21 11:46 AM, Townes Olson wrote:
> On Sunday, November 28, 2021 at 7:14:18 AM UTC-8, det...@outlook.com
> wrote:
>>>> A LIDAR GUN can only be operated while stationary because it
>>>> has no way to measure its own speed.
>>>>
>>> Not true. It so happens that most common LIDAR speed guns are of
>>> the “stationary” variety, meaning they just send a signal to the
>>> target to yield the rate of change of the distance between gun
>>> and target, but it’s also possible to create a “moving LIDAR”
>>> device that sends two signals, one to the target and one to some
>>> background object on the road, and subtract the two, just like
>>> “moving radar”.
>>
>> It may be "possible"…
>
> May be? There’s no need to be tentative about it. It not only may
> be possible, it clearly *is* possible. A simple LIDAR speed gun
> gives the relative speed between gun and target, it can be pointed at
> a citizen’s car and then pointed at a road sign (for example), and
> the difference between the two relative speeds is the speed of the
> citizen’s car relative to the road sign (taking the cosine effect
> into account).

For police the issue is obtaining evidence valid in court. Current LIDAR
systems can only be used while stationary (relative to the road). While
it is in principle possible for a LIDAR system to measure its own speed,
in practice none of them do so.

Since the LIDAR beam is so narrow, to use it from a moving vehicle would
require either:
a) interface into the vehicle's speedometer
or
b) the officer first takes a reading on the target, and then takes
a reading on an object that is stationary relative to the road.
Neither of these is feasible in the context of law enforcement, (a)
because such interface is not available, and (b) because it is too
cumbersome, and because there are too many holes for a defense attorney
to use to discredit the testimony.

Tom Roberts

On Monday, November 29, 2021 at 9:16:48 AM UTC-8, tjrob137 wrote:
> For police the issue is obtaining evidence valid in court. Current LIDAR
> systems can only be used while stationary (relative to the road). While
> it is in principle possible for a LIDAR system to measure its own speed,
> in practice none of them do so.

Right, the point is to dispel Ed’s belief that radar (unlike LIDAR) can intrinsically determine its own absolute speed just by bouncing signals internally off its own radome (for example). That’s what he was alluding to when he said “A LIDAR GUN can only be operated while stationary because it has no way to measure its own speed.” You see, he has this weird belief that a radar gun has a magical way of determining it’s own Edspeed (which he usually defines as being relative to the earth… but not always) intrinsically. The point is that Ed’s belief is wrong, because a LIDAR gun is just as capable of measuring it’s speed relative to the ground as a radar gun is, and in the same way, namely, by pointing it at an object at rest on the ground.

Again, the message to Ed is that a primitive speed gun, either radar and LIDAR, simply measures the relative speed (i.e., rate of change of the distance) between gun and target using the Doppler effect, and hence it reads the target’s road speed (straight on) only when the gun is at rest on the road. These simple devices are called “stationary” speed guns. Now, we could also construct radar and LIDAR devices that examine reflections from the background, and compute the difference. The fact that “moving speed guns” have practical drawbacks and their readings are more subject to judicial dispute is beside the point.

Townes Olson <townesolson7@gmail.com> wrote:
> On Monday, November 29, 2021 at 9:16:48 AM UTC-8, tjrob137 wrote:
>> For police the issue is obtaining evidence valid in court. Current LIDAR
>> systems can only be used while stationary (relative to the road). While
>> it is in principle possible for a LIDAR system to measure its own speed,
>> in practice none of them do so.
>
> Right, the point is to dispel Ed’s belief that radar (unlike LIDAR) can
> intrinsically determine its own absolute speed just by bouncing signals
> internally off its own radome (for example). That’s what he was alluding
> to when he said “A LIDAR GUN can only be operated while stationary
> because it has no way to measure its own speed.” You see, he has this
> weird belief that a radar gun has a magical way of determining it’s own
> Edspeed (which he usually defines as being relative to the earth… but not
> always) intrinsically. The point is that Ed’s belief is wrong, because a
> LIDAR gun is just as capable of measuring it’s speed relative to the
> ground as a radar gun is, and in the same way, namely, by pointing it at
> an object at rest on the ground.
>
> Again, the message to Ed is that a primitive speed gun, either radar and
> LIDAR, simply measures the relative speed (i.e., rate of change of the
> distance) between gun and target using the Doppler effect, and hence it
> reads the target’s road speed (straight on) only when the gun is at rest
> on the road. These simple devices are called “stationary” speed guns.
> Now, we could also construct radar and LIDAR devices that examine
> reflections from the background, and compute the difference. The fact
> that “moving speed guns” have practical drawbacks and their readings are
> more subject to judicial dispute is beside the point.
>
>

I’ll just add that Ed has no conceptual grip on relative velocity. Very
much like Ken Seto, he believes that relative velocity is just a difference
between two “real” velocities, and that the only way to obtain a relative
velocity is to first measure those “real” velocities and then subtract
them. This is very deeply rooted in their calcified brains, and it makes so
much “natural” sense to them that mere words will not uproot it.

The principle difference between Ed and Ken on this score is the reference
for this “real” velocity. For Ken, it is an absolute velocity referenced to
an imagined ether. For Ed, the reference is the nearest large and
unpropelled body, in many cases the surface of the Earth. If the experiment
were done on Mars, it would be the surface of Mars. If it were done in
intergalactic space, he would choose some immovable center of the universe,
which he imagines everything was propelled from by the Big Bang.

--
Odd Bodkin -- maker of fine toys, tools, tables

El lunes, 29 de noviembre de 2021 a las 17:35:23 UTC-3, bodk...@gmail.com escribió:
> Townes Olson <townes...@gmail.com> wrote:
> > On Monday, November 29, 2021 at 9:16:48 AM UTC-8, tjrob137 wrote:
> >> For police the issue is obtaining evidence valid in court. Current LIDAR
> >> systems can only be used while stationary (relative to the road). While
> >> it is in principle possible for a LIDAR system to measure its own speed,
> >> in practice none of them do so.
> >
> > Right, the point is to dispel Ed’s belief that radar (unlike LIDAR) can
> > intrinsically determine its own absolute speed just by bouncing signals
> > internally off its own radome (for example). That’s what he was alluding
> > to when he said “A LIDAR GUN can only be operated while stationary
> > because it has no way to measure its own speed.” You see, he has this
> > weird belief that a radar gun has a magical way of determining it’s own
> > Edspeed (which he usually defines as being relative to the earth… but not
> > always) intrinsically. The point is that Ed’s belief is wrong, because a
> > LIDAR gun is just as capable of measuring it’s speed relative to the
> > ground as a radar gun is, and in the same way, namely, by pointing it at
> > an object at rest on the ground.
> >
> > Again, the message to Ed is that a primitive speed gun, either radar and
> > LIDAR, simply measures the relative speed (i.e., rate of change of the
> > distance) between gun and target using the Doppler effect, and hence it
> > reads the target’s road speed (straight on) only when the gun is at rest
> > on the road. These simple devices are called “stationary” speed guns.
> > Now, we could also construct radar and LIDAR devices that examine
> > reflections from the background, and compute the difference. The fact
> > that “moving speed guns” have practical drawbacks and their readings are
> > more subject to judicial dispute is beside the point.
> >
> >
> I’ll just add that Ed has no conceptual grip on relative velocity.. Very
> much like Ken Seto, he believes that relative velocity is just a difference
> between two “real” velocities, and that the only way to obtain a relative
> velocity is to first measure those “real” velocities and then subtract
> them. This is very deeply rooted in their calcified brains, and it makes so
> much “natural” sense to them that mere words will not uproot it.
>
> The principle difference between Ed and Ken on this score is the reference
> for this “real” velocity. For Ken, it is an absolute velocity referenced to
> an imagined ether. For Ed, the reference is the nearest large and
> unpropelled body, in many cases the surface of the Earth. If the experiment
> were done on Mars, it would be the surface of Mars. If it were done in
> intergalactic space, he would choose some immovable center of the universe,
> which he imagines everything was propelled from by the Big Bang.
> --
> Odd Bodkin -- maker of fine toys, tools, tables

In his web site (http://www.ed-lake.com/) today Lake recognizes his mistakes (first time in so many years) and says he will withdraw some of his publications in vixra. Hopefully he will recognize he learned something from this group (but I do not count on it).

Paparios <mrios@ing.puc.cl> wrote:
> El lunes, 29 de noviembre de 2021 a las 17:35:23 UTC-3, bodk...@gmail.com escribió:
>> Townes Olson <townes...@gmail.com> wrote:
>>> On Monday, November 29, 2021 at 9:16:48 AM UTC-8, tjrob137 wrote:
>>>> For police the issue is obtaining evidence valid in court. Current LIDAR
>>>> systems can only be used while stationary (relative to the road). While
>>>> it is in principle possible for a LIDAR system to measure its own speed,
>>>> in practice none of them do so.
>>>
>>> Right, the point is to dispel Ed’s belief that radar (unlike LIDAR) can
>>> intrinsically determine its own absolute speed just by bouncing signals
>>> internally off its own radome (for example). That’s what he was alluding
>>> to when he said “A LIDAR GUN can only be operated while stationary
>>> because it has no way to measure its own speed.” You see, he has this
>>> weird belief that a radar gun has a magical way of determining it’s own
>>> Edspeed (which he usually defines as being relative to the earth… but not
>>> always) intrinsically. The point is that Ed’s belief is wrong, because a
>>> LIDAR gun is just as capable of measuring it’s speed relative to the
>>> ground as a radar gun is, and in the same way, namely, by pointing it at
>>> an object at rest on the ground.
>>>
>>> Again, the message to Ed is that a primitive speed gun, either radar and
>>> LIDAR, simply measures the relative speed (i.e., rate of change of the
>>> distance) between gun and target using the Doppler effect, and hence it
>>> reads the target’s road speed (straight on) only when the gun is at rest
>>> on the road. These simple devices are called “stationary” speed guns.
>>> Now, we could also construct radar and LIDAR devices that examine
>>> reflections from the background, and compute the difference. The fact
>>> that “moving speed guns” have practical drawbacks and their readings are
>>> more subject to judicial dispute is beside the point.
>>>
>>>
>> I’ll just add that Ed has no conceptual grip on relative velocity. Very
>> much like Ken Seto, he believes that relative velocity is just a difference
>> between two “real” velocities, and that the only way to obtain a relative
>> velocity is to first measure those “real” velocities and then subtract
>> them. This is very deeply rooted in their calcified brains, and it makes so
>> much “natural” sense to them that mere words will not uproot it.
>>
>> The principle difference between Ed and Ken on this score is the reference
>> for this “real” velocity. For Ken, it is an absolute velocity referenced to
>> an imagined ether. For Ed, the reference is the nearest large and
>> unpropelled body, in many cases the surface of the Earth. If the experiment
>> were done on Mars, it would be the surface of Mars. If it were done in
>> intergalactic space, he would choose some immovable center of the universe,
>> which he imagines everything was propelled from by the Big Bang.
>> --
>> Odd Bodkin -- maker of fine toys, tools, tables
>
> In his web site (http://www.ed-lake.com/) today Lake recognizes his
> mistakes (first time in so many years) and says he will withdraw some of
> his publications in vixra. Hopefully he will recognize he learned
> something from this group (but I do not count on it).
>

Oh my. Indeed.

“Plus, while it is good to learn from one’s mistakes, it is not so good to
display your mistakes for all the world to see or to talk about them day
after day and week after week.”

Others might take note.

--
Odd Bodkin — Maker of fine toys, tools, tables

On Monday, November 29, 2021 at 3:49:18 PM UTC-6, Paparios wrote:
> El lunes, 29 de noviembre de 2021 a las 17:35:23 UTC-3, bodk...@gmail.com escribió:
> > Townes Olson <townes...@gmail.com> wrote:
> > > On Monday, November 29, 2021 at 9:16:48 AM UTC-8, tjrob137 wrote:
> > >> For police the issue is obtaining evidence valid in court. Current LIDAR
> > >> systems can only be used while stationary (relative to the road). While
> > >> it is in principle possible for a LIDAR system to measure its own speed,
> > >> in practice none of them do so.
> > >
> > > Right, the point is to dispel Ed’s belief that radar (unlike LIDAR) can
> > > intrinsically determine its own absolute speed just by bouncing signals
> > > internally off its own radome (for example). That’s what he was alluding
> > > to when he said “A LIDAR GUN can only be operated while stationary
> > > because it has no way to measure its own speed.” You see, he has this
> > > weird belief that a radar gun has a magical way of determining it’s own
> > > Edspeed (which he usually defines as being relative to the earth… but not
> > > always) intrinsically. The point is that Ed’s belief is wrong, because a
> > > LIDAR gun is just as capable of measuring it’s speed relative to the
> > > ground as a radar gun is, and in the same way, namely, by pointing it at
> > > an object at rest on the ground.
> > >
> > > Again, the message to Ed is that a primitive speed gun, either radar and
> > > LIDAR, simply measures the relative speed (i.e., rate of change of the
> > > distance) between gun and target using the Doppler effect, and hence it
> > > reads the target’s road speed (straight on) only when the gun is at rest
> > > on the road. These simple devices are called “stationary” speed guns.
> > > Now, we could also construct radar and LIDAR devices that examine
> > > reflections from the background, and compute the difference. The fact
> > > that “moving speed guns” have practical drawbacks and their readings are
> > > more subject to judicial dispute is beside the point.
> > >
> > >
> > I’ll just add that Ed has no conceptual grip on relative velocity. Very
> > much like Ken Seto, he believes that relative velocity is just a difference
> > between two “real” velocities, and that the only way to obtain a relative
> > velocity is to first measure those “real” velocities and then subtract
> > them. This is very deeply rooted in their calcified brains, and it makes so
> > much “natural” sense to them that mere words will not uproot it.
> >
> > The principle difference between Ed and Ken on this score is the reference
> > for this “real” velocity. For Ken, it is an absolute velocity referenced to
> > an imagined ether. For Ed, the reference is the nearest large and
> > unpropelled body, in many cases the surface of the Earth. If the experiment
> > were done on Mars, it would be the surface of Mars. If it were done in
> > intergalactic space, he would choose some immovable center of the universe,
> > which he imagines everything was propelled from by the Big Bang.
> > --
> > Odd Bodkin -- maker of fine toys, tools, tables
> In his web site (http://www.ed-lake.com/) today Lake recognizes his mistakes (first time in so many years) and says he will withdraw some of his publications in vixra. Hopefully he will recognize he learned something from this group (but I do not count on it).

Actually it's the SECOND time in a couple years. The first time was when I learned
that photons from a moving radar gun hit an approaching target at c+v and then the
returning photons hit the approaching gun at c+v. I thought the returning photons
would hit at c.

I've only withdrawn my paper on "Relativity and Radar Guns." It has the same error
as version #9 of my paper "Radar Guns and Einstein's Theories." I'll correct that
version. There's no point in having two papers with the same error and correcting
both.

I learn from this group, but not in the way you think. Your repeated declarations of
mathematical formulas don't help in any way. I learn by explaining things to you
in a dozen different ways, because you seem to accept none of them. But
explaining things in different ways forces me to view things from different angles.
So, I'm "figuring things out" as I explain things.

Ed

Tom Roberts wrote:

> a) interface into the vehicle's speedometer
> or
> b) the officer first takes a reading on the target, and then takes
> a reading on an object that is stationary relative to the road.
> Neither of these is feasible in the context of law enforcement, (a)
> because such interface is not available, and (b) because it is too
> cumbersome, and because there are too many holes for a defense attorney
> to use to discredit the testimony.

but it's done and used. It depends on the legislation of the country,
whether it suffices as testimony. On highways for instance it's actually
hard to measure speeds from fixed positions.

On Monday, November 29, 2021 at 2:14:39 PM UTC-8, det...@outlook.com wrote:
> ..photons from a moving radar gun hit an approaching target at c+v and then the
> returning photons hit the approaching gun at c+v.

When you say "an approaching target", do you mean the target is actually approaching (i.e., getting closer to) the gun? Or are you talking about a case where the gun and target are both moving at speed v in the same direction relative to the ground, such as inside the back of a truck? In that case, if the truck is moving in the direction that the gun in pointing, the target will be moving away from the light, whereas on the return leg the gun will be moving toward the light. So wouldn't your belief be that the photons hit the target at c-v, and then hit the gun at c+v? (You still agree that the speed of light is c relative to the ground's system of reference, right?)

On 11/29/21 2:13 PM, Townes Olson wrote:
> [...]

While LIDAR systems cannot measure their own speed relative to the
ground without unrealistic support from other systems, many police RADAR
guns can do so (those certified for operation in a moving vehicle). They
do this by using two beams simultaneously (or sequentially but so
quickly that to a human they seem simultaneous) -- they are essentially
two radar guns in one package. One beam is narrow, and used to measure
the speed of the target relative to the gun [#]. The other beam is very
wide, and reflects from many objects at rest relative to the road; they
use heuristic algorithms to remove any moving objects from consideration
to get the speed of the vehicle relative to the road [@]. The speeds
computed from the two beams are subtracted to obtain the speed of the
target relative to the road [%].

[#] Really relative to the locally inertial frame in which
the gun is at rest when the measurement is performed.

[@] Really the speed of those objects relative to the
inertial frame in which the gun is at rest when the
measurement is performed.

[%] Galilean relativity is accurate enough; relativistic
corrections are not needed.

This has all been discussed repeatedly ad nauseum, but Lake keeps
demonstrating that he is unable to understand....

Tom Roberts

On Monday, November 29, 2021 at 8:19:26 PM UTC-8, tjrob137 wrote:

> This has all been discussed repeatedly ad nauseum, but Lake keeps
> demonstrating that he is unable to understand....

.... and this is not going to change anytime soon, if ever...

On Monday, November 29, 2021 at 8:19:26 PM UTC-8, tjrob137 wrote:
> LIDAR systems cannot measure their own speed relative to the
> ground without unrealistic support from other systems…

You are mistaken. Again, a LIDAR speed gun can measure its own ground speed just as easily as can a radar speed gun, and in exactly the same way: Just point it at a road sign up ahead. Making use of this, it is trivial to design a device that sends a range of outputs and examines the returns from the target as well as background to give the road speed of the target. The fact that stationary speed guns are often preferred by law enforcement because they are less subject to dispute is neither here nor there. Also, the different reflectivities of common objects at radar and LIDAR frequencies is not relevant to the principle of operation.

> …many police RADAR guns can do so … They do this by using two beams
> simultaneously (or sequentially but so quickly that to a human they seem
> simultaneous) -- they are essentially two radar guns in one package.
> One beam is narrow… The other beam is very wide…

There are many ways of designing a “moving” device… it is sufficient to just send a single outward wave and examine the spectrum of the return signal. It’s easy to identify and distinguish the background from the target, due to the cosine effect leading to a predictable ramp shape in the background intensity, compared with the sharp peak at the target frequency. You can learn about this in any good book that describes radar and LIDAR speed guns in detail.

On Monday, November 29, 2021 at 9:52:28 PM UTC-6, Townes Olson wrote:
> On Monday, November 29, 2021 at 2:14:39 PM UTC-8, wrote:
> > ..photons from a moving radar gun hit an approaching target at c+v and then the
> > returning photons hit the approaching gun at c+v.
> When you say "an approaching target", do you mean the target is actually approaching (i.e., getting closer to) the gun?

Of course.

> Or are you talking about a case where the gun and target are both moving at speed v in the same direction relative to the ground, such as inside the back of a truck?

The wall never "approaches" the radar gun in such situations. Those situations are
about LIGHT traveling at c hitting a wall that is NOT stationary.

> In that case, if the truck is moving in the direction that the gun in pointing, the target will be moving away from the light, whereas on the return leg the gun will be moving toward the light. So wouldn't your belief be that the photons hit the target at c-v, and then hit the gun at c+v?

That WAS my belief. Now I'm not so sure. Everything inside the truck is moving at the
same speed, so rate of time (velocity time dilation) is NOT a factor. But ENERGY IS a factor.
When a photon hits an approaching target traveling at v, the photon will hit at c+v where v
is the speed of the target AND v relates to the amount of ADDITIONAL ENERGY added to
the photon by impacting the approaching target.

> (You still agree that the speed of light is c relative to the ground's system of reference, right?)

No, I never agreed to that. The speed of light is always c, but c is 186,282 miles PER SECOND,
and a second is shorter on the ground than in a vehicle (or radar gun) moving at 70 mph.
Many many experiments demonstrate time dilation.

When working with a moving radar gun, you can have 5 different situations:

1. The radar gun is moving but the target is "stationary."
2. The radar gun is moving and the target is moving directly toward the radar gun.
3. The radar gun is moving and the target is moving directly away from the radar gun.
4. The radar gun is inside a moving container but it is "stationary" relative to the container.
5. The radar gun is moving and the target is moving at some angle to the radar gun.

The problem is trying to understand EXACTLY what the radar gun is measuring in
each of those situations.

Ed

On Monday, November 29, 2021 at 11:38:14 PM UTC-6, Townes Olson wrote:
> On Monday, November 29, 2021 at 8:19:26 PM UTC-8, tjrob137 wrote:

> > …many police RADAR guns can do so … They do this by using two beams
> > simultaneously (or sequentially but so quickly that to a human they seem
> > simultaneous) -- they are essentially two radar guns in one package.
> > One beam is narrow… The other beam is very wide…
>
> There are many ways of designing a “moving” device… it is sufficient to just send a single outward wave and examine the spectrum of the return signal. It’s easy to identify and distinguish the background from the target, due to the cosine effect leading to a predictable ramp shape in the background intensity, compared with the sharp peak at the target frequency. You can learn about this in any good book that describes radar and LIDAR speed guns in detail.

Ultimately, everything boils down to utility and economics.

You describe a radar gun that performs sophisticated FFT analysis of
individual broadly divergent pulses. That would be great, but how much would
it cost? Would it fit into typical police department budgets?

In the case of LIDAR, the paper that Ed presented indicated that police
LIDAR speed guns are all of "conventional LIDAR" design, requiring analysis
of several seconds worth of data per line of sight speed determination. Given
the number of broadly divergent data points that would be required in the
analysis, I don't believe that conventional LIDAR could be utilized in a moving
device, certainly not one that could be used safely by a patrolling policeman.
One would need to build such a device around -Doppler- LIDAR. How much
would such a device cost?

Have you seen such devices marketed?

I imagine that costs are going down rapidly due to the use of LIDAR in
autonomous vehicles, cell phones, etc. Still, a practical moving Doppler
LIDAR speed gun suitable for police use seems to me to be several years
off.

I wouldn't be surprised to have to eat my words, though.

On November 28, bodk...@gmail.com wrote:
>> Is there any way to do that, in principle, without running in circles?
>> i.e. To measure the one way light speed, we need synchronized
>> clocks at a distance... the sync procedures assume spatial isotropy...
>> to test isotropy, we measure light speed in various directions...
>> which requires sync'd clocks...
>
> No, not quite. Isotropy can be measured a variety of ways without two
> clocks.
> As a simple example, ride to the store on a bicycle in a headwind, which
> will turn into a tailwind on return. Let’s suppose that without the wind,
> you ride at an isotropic 15 mph,

hmmmm.... we're trying to test isotropy.
How do you know it's 15 mph, in each direction? (i.e. isotropic)
Well, you have a speedometer, which measures mph...
miles per hour.... what's an hour? It's what a clock measures.
How do you know the clock operates the same, in each direction?
Because space is isotropic... are you sure of that?

The question is subtler than you realize.

> but the wind introduces an anisotropy, so
> that you ride at 10 mph on the way to the store and 20 mph on the way back.

--
Rich

On November 29, det...@outlook.com wrote:
>> In his web site (http://www.ed-lake.com/) today Lake recognizes his mistakes
>> and says he will withdraw some of his publications in vixra.
>
> The first time was when I learned that photons from a moving radar gun hit an
> approaching target at c+v and then the returning photons hit the approaching gun
> at c+v.

It's nice to see you've learned something from your participation here.
> I learn from this group, but not in the way you think.
> I learn by explaining things to you in a dozen different ways,
> But explaining things in different ways forces me to
> view things from different angles.
> So, I'm "figuring things out" as I explain things.

"To teach is to learn."
- Confushus, or Boodah, or somebody

Your hero Richard Feynman said that he preferred the academic environment
over think tanks, because those tanks are stagnant. Whereas in university,
there are curious students asking stupid questions, which is stimulating and constructive.

So your function here is like Feynman at Caltech! Isn't that something?

--
Rich

On Tuesday, November 30, 2021 at 7:57:39 AM UTC-8, det...@outlook.com wrote:
> > > ..photons from a moving radar gun hit an approaching target at c+v and then the
> > > returning photons hit the approaching gun at c+v.
> > When you say "an approaching target", do you mean the target is actually approaching (i.e., getting closer to) the gun?
>
> Of course.

In that case, there are two speeds involved: you have a moving radar gun and an approaching target, so let’s say the speed of the target (relative to the ground) is v, and the speed of the gun (relative to the ground) is u. What do you think is the speed of light, outbound and return, relative to the ground? And what do you think is the speed relative to the gun, and relative to the target?

> > Or are you talking about a case where the gun and target are both moving at speed v in the same direction relative to the ground, such as inside the back of a truck?
> > In that case, if the truck is moving in the direction that the gun in pointing, the target will be moving away from the light, whereas on the return leg the gun will be moving toward the light. So wouldn't your belief be that the photons hit the target at c-v, and then hit the gun at c+v?
>
> That WAS my belief. Now I'm not so sure.

Okay, but that makes it difficult to assess your claims… you don’t seem to be making any claims, just expressing confusion and uncertainty. That’s good, because your original beliefs were clearly untenable and inconsistent.

> Everything inside the truck is moving at the same speed, so rate
> of time (velocity time dilation) is NOT a factor.

As you know, even for small speeds such as car speeds, relativistic time dilation is much too small to have any relevance.

> You still agree that the speed of light is c relative to the ground's system of reference, right?
>
> No, I never agreed to that.

Well, that's strange. You have explicitly stated that many times.

> When working with a moving radar gun, you can have 5 different situations:
> 1. The radar gun is moving but the target is "stationary."
> 2. The radar gun is moving and the target is moving directly toward the radar gun.
> 3. The radar gun is moving and the target is moving directly away from the radar gun.
> 4. The radar gun is inside a moving container but it is "stationary" relative to the container.
> 5. The radar gun is moving and the target is moving at some angle to the radar gun.
> The problem is trying to understand EXACTLY what the radar gun is measuring in
> each of those situations.

In each case the gun is measuring the rate of change of the distance between gun and target.

On Tuesday, November 30, 2021 at 7:57:41 AM UTC-8, prokaryotic.c...@gmail.com wrote:
> You describe a radar gun that performs sophisticated FFT analysis of
> individual broadly divergent pulses. That would be great, but how much would
> it cost? Would it fit into typical police department budgets?

This is just how such devices work. You can read about this is any good book on the subject. Try, for example, “Principles of Modern Radar, Radar Applications” by Melvin and Scheer (Editors). See section 10..1 on how the spectral analysis is performed. Needless to say, the idea of duct taping two guns together is just silly.

> I don't believe that conventional LIDAR could be utilized in a moving device

You can easily do it by hand with a simple LIDAR gun, and that could certainly be automated.

> One would need to build such a device around -Doppler- LIDAR.

No (although “Doppler LIDAR” also exists).

On Wednesday, December 1, 2021 at 8:55:50 AM UTC-6, Townes Olson wrote:
> On Tuesday, November 30, 2021 at 7:57:41 AM UTC-8, prokaryotic.c...@gmail..com wrote:
> > You describe a radar gun that performs sophisticated FFT analysis of
> > individual broadly divergent pulses. That would be great, but how much would
> > it cost? Would it fit into typical police department budgets?
> This is just how such devices work. You can read about this is any good book on the subject. Try, for example, “Principles of Modern Radar, Radar Applications” by Melvin and Scheer (Editors). See section 10.1 on how the spectral analysis is performed.

While I was at Lockheed the first time, I did most of the programming work on
a "High Speed Data Test Set" which, among other things, was used for testing
out pulsed-Doppler radar systems, so you don't have to be all condescending
trying to explain to me how they work, thank you.

> Needless to say, the idea of duct taping two guns together is just silly.
> > I don't believe that conventional LIDAR could be utilized in a moving device
> You can easily do it by hand with a simple LIDAR gun, and that could certainly be automated.
> > One would need to build such a device around -Doppler- LIDAR.
> No (although “Doppler LIDAR” also exists).

You are completely ignoring the two areas of concern that I emphasized
as being very important: Utility and Economics.

Utility question: Don't you think that it would be rather dangerous for a cop
to have to aim a handheld LIDAR at a speeding car while the cop is also
driving? I don't see a valid use case for handheld speed guns in a moving
vehicle.

Economics question: The only safe solution would be to borrow technology
from the latest generation of autonomous vehicles, broadcasting laser
pulses over a broad range of angles so that moving and stationary targets
could be concurrently monitored, along with camera shots. Sophisticated
algorithms would be applied to the data so that speed readings could
be associated with specific cars in the camera shots. Automotive LIDAR
technology is constantly improving and decreasing in cost, but how much
would it cost to develop an automated LIDAR speed monitoring system
that can be used in a moving vehicle? Do you know of any such systems
in development? The market is rather small, so there would be only limited
economies of scale. In other words, I am asking whether they would be
affordable.

On Wednesday, December 1, 2021 at 3:09:00 PM UTC-8, prokaryotic.c...@gmail.com wrote:
> > > You describe a radar gun that performs sophisticated FFT analysis of
> > > individual broadly divergent pulses. That would be great, but how much would
> > > it cost? Would it fit into typical police department budgets?
> > This is just how such devices work. You can read about this is any good book on the subject. Try, for example, “Principles of Modern Radar, Radar Applications” by Melvin and Scheer (Editors). See section 10.1 on how the spectral analysis is performed.
> …you don't have to be all condescending trying to explain to me how they work…

The point is that the “sophisticated FFT analysis” I described, which you suggested would be highly advanced technology and not economically unfeasible, is precisely how commonly-available police radar guns work. I even provided you with an easily accessible online reference.

> You are completely ignoring … Utility and Economics.

The only function of the concept of “moving LIDAR” in this discussion is to dispel Ed’s claim that radar guns can sense their own unique Edspeed inside an enclosed compartment without measuring their speed relative to something else. Ed claimed that radar guns can do this, but that LIDAR guns cannot. In truth, neither device can do that, but both devices can equally well measure their own speed (on the road) merely by being pointed at a parked car. This is how moving speed guns work, by measuring the relative speed of the target and of the ground, and adding or subtracting the two. This disposes of Ed’s belief. The comparative cost of radar and LIDAR technology is not relevant to this discussion, and, as noted above, your sense of the state of the art of cheap signal processing is off the mark.

On Wednesday, December 1, 2021 at 6:53:00 PM UTC-6, Townes Olson wrote:
> On Wednesday, December 1, 2021 at 3:09:00 PM UTC-8, prokaryotic.c...@gmail.com wrote:
> > > > You describe a radar gun that performs sophisticated FFT analysis of
> > > > individual broadly divergent pulses. That would be great, but how much would
> > > > it cost? Would it fit into typical police department budgets?
> > > This is just how such devices work. You can read about this is any good book on the subject. Try, for example, “Principles of Modern Radar, Radar Applications” by Melvin and Scheer (Editors). See section 10.1 on how the spectral analysis is performed.
> > …you don't have to be all condescending trying to explain to me how they work…
>
> The point is that the “sophisticated FFT analysis” I described, which you suggested would be highly advanced technology and not economically unfeasible, is precisely how commonly-available police radar guns work. I even provided you with an easily accessible online reference.

OK, I checked. You're right and I was wrong about the economics of pulsed-Doppler
police radars capable of simultaneously monitoring stationary objects and moving
vehicle from a moving vehicle.

But I still contend that the idea of a HANDHELD pulsed-Doppler radar from a moving
vehicle is scary, as scary as people texting while driving Such radars would have to be
mounted on the police vehicle. The policeman would perform a visual identification
of the speeding vehicle, and courts in general would back up a policeman's testimony

> > You are completely ignoring … Utility and Economics.
>
> The only function of the concept of “moving LIDAR” in this discussion is to dispel Ed’s claim that radar guns can sense their own unique Edspeed inside an enclosed compartment without measuring their speed relative to something else. Ed claimed that radar guns can do this, but that LIDAR guns cannot. In truth, neither device can do that, but both devices can equally well measure their own speed (on the road) merely by being pointed at a parked car. This is how moving speed guns work, by measuring the relative speed of the target and of the ground, and adding or subtracting the two. This disposes of Ed’s belief. The comparative cost of radar and LIDAR technology is not relevant to this discussion, and, as noted above, your sense of the state of the art of cheap signal processing is off the mark.

Excluding the issue of cost, it would be dangerous for a patrolling police officer to
use a handheld LIDAR to perform two measurements of speeding vehicle and
stationary object while driving. So again, such a system should in all probability be
vehicle mounted, using an adaptation of automotive LIDAR systems.

inbreed cretin rotchm wrote:

>> No. It clearly states up there that we have no idea where the ray comes
>> from.
>
>
> No rebuttal? So you agree that you did not understand what you read or
> that you lied?

stop spamming, you stupid sack of shit.