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E=mc2

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  E=mc2 Omar Shabsigh <omar.shabsigh@gmail.com> - 2018-11-01 14:43 -0700
    Re: E=mc2 Odd Bodkin <bodkinodd@gmail.com> - 2018-11-01 22:55 +0000
    E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-01 16:04 -0700
      Re: E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-02 09:21 -0700
        Re: E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-02 09:52 -0700
          Re: E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-02 15:28 -0700
    Re: E=mc2 Omar Shabsigh <omar.shabsigh@gmail.com> - 2018-11-01 17:53 -0700
      Re: E=mc2 Odd Bodkin <bodkinodd@gmail.com> - 2018-11-02 01:02 +0000
      Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-02 18:43 +0100
        Re: E=mc2 mlwozniak@wp.pl - 2018-11-02 11:21 -0700
    Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-02 13:35 +1100
      Re: E=mc2 mitchrae3323@gmail.com - 2018-11-01 21:43 -0700
      Re: E=mc2 The Starmaker <starmaker@ix.netcom.com> - 2018-11-01 23:09 -0700
      Re: E=mc2 mlwozniak@wp.pl - 2018-11-02 01:33 -0700
      Re: E=mc2 Buck Dehner <uktoa@yswdoez.cb> - 2018-11-04 12:34 +0000
        Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-04 14:20 +0100
          Re: E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-04 05:51 -0800
          Re: E=mc2 Buck Dehner <uktoa@yswdoez.cb> - 2018-11-05 20:51 +0000
            Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-06 10:57 +1100
              Re: E=mc2 Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-06 20:21 +0000
                Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-07 08:57 +1100
                  Re: E=mc2 Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-07 19:35 +0000
                    Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-08 09:32 +1100
                      Re: E=mc2 Gaston Castaneda <agn@j2awdos.nc> - 2018-11-08 21:13 +0000
                        Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-08 22:26 +0100
                          Re: E=mc2 Gaston Castaneda <ucpp@j2adosw.nv> - 2018-11-09 19:46 +0000
                            Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-10 02:47 +0100
                Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-07 00:13 +0100
                  Re: E=mc2 Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-07 19:38 +0000
        Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 13:17 -0500
          Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-04 20:01 +0100
            Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 14:38 -0500
              Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-04 20:53 +0100
                Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 18:01 -0500
                  Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-05 01:58 +0100
                    Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 22:59 -0500
                      Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-05 05:39 +0100
                    Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-05 07:54 +0100
                      Re: E=mc2 Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-05 22:33 -0600
                        Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-06 06:27 +0100
                        Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-06 06:28 +0100
                    Re: E=mc2 mlwozniak@wp.pl - 2018-11-04 23:28 -0800
              Re: E=mc2 Odd Bodkin <bodkinodd@gmail.com> - 2018-11-04 22:14 +0000
                Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 18:05 -0500
                  Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-05 02:02 +0100
                    Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 22:59 -0500
                      Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-05 05:51 +0100
                  Re: E=mc2 Odd Bodkin <bodkinodd@gmail.com> - 2018-11-05 03:00 +0000
                    Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 23:15 -0500
                      Re: E=mc2 Odd Bodkin <bodkinodd@gmail.com> - 2018-11-05 12:59 +0000
            Re: E=mc2 Buck Dehner <uktea@yswdoiz.cp> - 2018-11-05 21:00 +0000
              Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-13 15:38 +0100
                Re: E=mc2 Gaston Castaneda <uucp@jav4ow.nq> - 2018-11-13 20:22 +0000
                  Re: E=mc2 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-13 23:09 +0100
                    Re: E=mc2 Shon Wible <shwn@shouwe.wh> - 2018-11-14 15:53 +0000
          Re: E=mc2 Buck Dehner <uktoa@yswdoez.cb> - 2018-11-05 20:54 +0000
          Re: E=mc2 Steve BH <sbharris@gmail.com> - 2018-11-07 22:35 -0800
          Re: E=mc2 Steve BH <sbharris@gmail.com> - 2018-11-07 22:44 -0800
            Re: E=mc2 "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-08 06:34 -0800
        Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-05 12:21 +1100
          Re: E=mc2 benj <benj.fake@gmail.com> - 2018-11-04 23:12 -0500
            Re: E=mc2 Sylvia Else <sylvia@email.invalid> - 2018-11-05 16:30 +1100
    Re: E=mc2 Koobee Wublee <koobee.wublee@gmail.com> - 2018-11-02 16:48 -0700
      Re: E=mc2 mitchrae3323@gmail.com - 2018-11-02 19:07 -0700
      Re: E=mc2 Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-08 08:48 +0100

Page 3 of 4 — ← Prev page 1 2 [3] 4  Next page →

#476383

Tom Roberts <tjroberts137@sbcglobal.net> Wrote in message:
> But long after his death many physicists have found it convenient to formulate a theory which we call "Galilean relativity" -- it corresponds to SR, but uses the Galilean transforms.

This is what I have meant by the "current wording".


-- 
Libor Striz aka Poutnik ( a pilgrim/wanderer/wayfarer)

"Humour is the only effective weapon against stupidity."
Miloš Forman


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

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#476291

On Monday, 5 November 2018 01:58:25 UTC+1, Thomas 'PointedEars' Lahn  wrote:

> Proof by *experiment* and *history*.  *That* the Galilean transformation
> (there is no “Galilean relativity”) does NOT suffice to explain the observed
> electromagnetic phenomena, including light, was one thing that prompted
> Einstein to write “On the *Electrodynamics* of Moving Bodies”, now known as
> the first paper on special relativity, in the first place.

GT are simple coordinates equations.
Expecting them to explain it all is very 
stupid. But, of course, extreme stupidity 
is exactly what is expected from you.

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#476250

benj <benj.fake@gmail.com> wrote:
> On 11/4/2018 2:01 PM, Thomas 'PointedEars' Lahn wrote:
>> benj wrote:
>> 
>>> Wake up dumbass. You can prove E=mc² from Maxwell's equations.
>> 
>> No, but you can be _deduced_ from that, assuming that the special principle
>> of relativity holds.  That is precisely what Einstein did in his second
>> (“annus mirabilis”) 1905 paper on what became special relativity, “Does the
>> Inertia of a Body Depend Upon Its Energy Content?”:
>> 
>> <https://einsteinpapers.press.princeton.edu/vol2-trans/186>
>> 
>> Later, in 1929, Paul Dirac showed that it – and more generally, the
>> energy–momentum relation – can be derived from the properties of flat
>> spacetime alone:
>> 
>> With
>> 
>> p⃗    = γ m v⃗ = γ m (v_x, v_y, v_z)
>> P⃗    = (E/c, p⃗) = γ m (c, v⃗)
>> ||P⃗||² = (E/c)² − p⃗² = m²c²
>> 
>> one finds
>> 
>> E² = m²c⁴ + p⃗²c²
>> 
>> which gives for the *rest* energy (when v⃗ = 0)
>> 
>> E₀ = m c².
>> 
>> <https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relation>
>> 
>>> Exponent is squared.
>> 
>> Correct.
>> 
>> However, previously you have claimed the opposite of what follows from
>> Maxwell’s equations, namely that the isotropy of the speed of light would
>> merely be an assumption (instead of an experimental fact).
> 
> The Constancy of the speed of light was an assumption made by Einstein 
> to develop special relativity.

Which is in fact redundant, given the principle of relativity applied to
electrodynamics. 

> 
>> While it follows from Maxwell’s equations that which is an experimental
>> fact, namely that the speed of light c is isotropic as it only depends on
>> the electromagnetic properties of the medium through which (Maxwell’s)
>> electromagnetic waves, such as light, travel:
>> 
>> c = 1/√(ε₀ ε_r µ₀ µ_r).
>> 
>> So, are you retracting that claim?
> 
> However "[one can] develop relativistic electromagnetism solely on the 
> basis of electromagnetic retardation and the principle of [Galilean] 
> relativity without any additional postulates, hypotheses, or conjectures."
> 
> 
> 



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

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#476255

On 11/4/2018 5:14 PM, Odd Bodkin wrote:
> benj <benj.fake@gmail.com> wrote:
>> On 11/4/2018 2:01 PM, Thomas 'PointedEars' Lahn wrote:
>>> benj wrote:
>>>
>>>> Wake up dumbass. You can prove E=mc² from Maxwell's equations.
>>>
>>> No, but you can be _deduced_ from that, assuming that the special principle
>>> of relativity holds.  That is precisely what Einstein did in his second
>>> (“annus mirabilis”) 1905 paper on what became special relativity, “Does the
>>> Inertia of a Body Depend Upon Its Energy Content?”:
>>>
>>> <https://einsteinpapers.press.princeton.edu/vol2-trans/186>
>>>
>>> Later, in 1929, Paul Dirac showed that it – and more generally, the
>>> energy–momentum relation – can be derived from the properties of flat
>>> spacetime alone:
>>>
>>> With
>>>
>>> p⃗    = γ m v⃗ = γ m (v_x, v_y, v_z)
>>> P⃗    = (E/c, p⃗) = γ m (c, v⃗)
>>> ||P⃗||² = (E/c)² − p⃗² = m²c²
>>>
>>> one finds
>>>
>>> E² = m²c⁴ + p⃗²c²
>>>
>>> which gives for the *rest* energy (when v⃗ = 0)
>>>
>>> E₀ = m c².
>>>
>>> <https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relation>
>>>
>>>> Exponent is squared.
>>>
>>> Correct.
>>>
>>> However, previously you have claimed the opposite of what follows from
>>> Maxwell’s equations, namely that the isotropy of the speed of light would
>>> merely be an assumption (instead of an experimental fact).
>>
>> The Constancy of the speed of light was an assumption made by Einstein
>> to develop special relativity.
> 
> Which is in fact redundant, given the principle of relativity applied to
> electrodynamics.

Einstein didn't know it at the time. Nobody did, which was the whole 
question of the age. Glad to see that you have now won the "who is 
smarter than Einstein" contest again. Maybe you should argue like Mr. 
Vulcan that Einstein never said it. You've read all his books and papers.

>>
>>> While it follows from Maxwell’s equations that which is an experimental
>>> fact, namely that the speed of light c is isotropic as it only depends on
>>> the electromagnetic properties of the medium through which (Maxwell’s)
>>> electromagnetic waves, such as light, travel:
>>>
>>> c = 1/√(ε₀ ε_r µ₀ µ_r).
>>>
>>> So, are you retracting that claim?
>>
>> However "[one can] develop relativistic electromagnetism solely on the
>> basis of electromagnetic retardation and the principle of [Galilean]
>> relativity without any additional postulates, hypotheses, or conjectures."
>>
>>
>>
> 
> 
> 

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#476260

benj wrote:
> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>> benj <benj.fake@gmail.com> wrote:
>>> The Constancy of the speed of light was an assumption made by Einstein
>>> to develop special relativity.

It still was not.

>> Which is in fact redundant, given the principle of relativity applied to
>> electrodynamics.
> 
> Einstein didn't know it at the time.

But he did.  That the Galilean principle of relativity (which has nothing
to do with the Galilean transformation) seemed not applicable to
electrodynamics, but should have been, was what prompted his first paper
on the subject, as he wrote himself.

You have no clue what you are talking about.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#476275

On 11/4/2018 8:02 PM, Thomas 'PointedEars' Lahn wrote:
> 
> 
> benj wrote:
>> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>>> benj <benj.fake@gmail.com> wrote:
>>>> The Constancy of the speed of light was an assumption made by Einstein
>>>> to develop special relativity.
> 
> It still was not.
> 
>>> Which is in fact redundant, given the principle of relativity applied to
>>> electrodynamics.
>>
>> Einstein didn't know it at the time.
> 
> But he did.  That the Galilean principle of relativity (which has nothing
> to do with the Galilean transformation) seemed not applicable to
> electrodynamics, but should have been, was what prompted his first paper
> on the subject, as he wrote himself.
> 
> You have no clue what you are talking about.
> 
Pot - Kettle - black.

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#476282

benj wrote:
> On 11/4/2018 8:02 PM, Thomas 'PointedEars' Lahn wrote:
>> benj wrote:
>>> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>>>> [The Constancy of the speed of light was an assumption] is in fact redundant,
>>>> given the principle of relativity applied to electrodynamics.
>>> Einstein didn't know it at the time.
>>
>> But he did.  That the Galilean principle of relativity (which has
>> nothing to do with the Galilean transformation) seemed not applicable to
>> electrodynamics, but should have been, was what prompted his first paper
>> on the subject, as he wrote himself.
>>
>> You have no clue what you are talking about.
>
> Pot - Kettle - black.

LOL.

,-<https://einsteinpapers.press.princeton.edu/vol2-trans/154>
|
| It is well known that Maxwell’s electrodynamics – as usually understood at
| present – when applied to moving bodies, leads to asymmetries that do not
| seem to attach to the phenomena. Let us recall, for example, the electro-
| dynamic interaction between a magnet and a conductor. The observable
| phenomenon depends here only on the relative motion of conductor and
| magnet, while according to the customary conception the two cases, in
| which, respectively, either the one or the other of the two bodies is the
| one in motion, are to be strictly differentiated from each other. For if
| the magnet is in motion and the conductor is at rest, there arises in the
| surroundings of the magnet an electric field endowed with a certain energy
| value that produces a current in the places where parts of the conductor
| are located. But if the magnet is at rest and the conductor is in motion,
| no electric field arises in the surroundings of the magnet, while in the
| conductor an electromotive force will arise, to which in itself there does
| not correspond any energy, but which, provided that the relative motion in
| the two cases considered is the same, gives rise to electrical currents
| that have the same magnitude and the same course as those produced by the
| electric forces in the first-mentioned case.
|   Examples of a similar kind, and the failure of attempts to detect a
| motion of the earth relative to the “light medium”, lead to the conjecture
| that not only in mechanics, but in electrodynamics as well, the phenomena
| do not have any properties corresponding to the concept of absolute rest,
| but that in all coordinate systems in which the mechanical equations are
| valid, also the same electrodynamic and optical laws are valid, as has
| already been shown for quantities of the first order. We shall raise
| this conjecture (whose content will be called “the principle of
| relativity” hereafter) to the status of a postulate and shall introduce,
| in addition, the postulate, only seemingly incompatible with the former
| one, that in empty space light is always propagated with a definite
| velocity V which is independent of the state of motion of the emitting
| body.  These two postulates suffice for arriving at a simple and
| consistent electrodynamics of moving bodies on the basis of Maxwell's
| theory for bodies at rest. The introduction of a “light ether” will prove
| superfluous, inasmuch as in accordance with the concept to be developed
| here, no “space at absolute rest” endowed with special properties will be
| introduced, nor will a velocity vector be assigned to a point of empty
| space at which electromagnetic processes are taking place.
|    Like every other electrodynamics, the theory to be developed is based
| on the kinematics of the rigid body, since assertions of each and any
| theory concern the relations between rigid bodies (coordinate systems),
| clocks, and electromagnetic processes. Insufficient regard for this
| circumstance is at the root of the difficulties with which the
| electrodynamics of moving bodies must presently grapple.

  –Albert Einstein: “On the Electrodynamics of Moving Bodies” (1905),
   introduction (official translation)

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#476270

benj <benj.fake@gmail.com> wrote:
> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>> benj <benj.fake@gmail.com> wrote:
>>> On 11/4/2018 2:01 PM, Thomas 'PointedEars' Lahn wrote:
>>>> benj wrote:
>>>> 
>>>>> Wake up dumbass. You can prove E=mc² from Maxwell's equations.
>>>> 
>>>> No, but you can be _deduced_ from that, assuming that the special principle
>>>> of relativity holds.  That is precisely what Einstein did in his second
>>>> (“annus mirabilis”) 1905 paper on what became special relativity, “Does the
>>>> Inertia of a Body Depend Upon Its Energy Content?”:
>>>> 
>>>> <https://einsteinpapers.press.princeton.edu/vol2-trans/186>
>>>> 
>>>> Later, in 1929, Paul Dirac showed that it – and more generally, the
>>>> energy–momentum relation – can be derived from the properties of flat
>>>> spacetime alone:
>>>> 
>>>> With
>>>> 
>>>> p⃗    = γ m v⃗ = γ m (v_x, v_y, v_z)
>>>> P⃗    = (E/c, p⃗) = γ m (c, v⃗)
>>>> ||P⃗||² = (E/c)² − p⃗² = m²c²
>>>> 
>>>> one finds
>>>> 
>>>> E² = m²c⁴ + p⃗²c²
>>>> 
>>>> which gives for the *rest* energy (when v⃗ = 0)
>>>> 
>>>> E₀ = m c².
>>>> 
>>>> <https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relation>
>>>> 
>>>>> Exponent is squared.
>>>> 
>>>> Correct.
>>>> 
>>>> However, previously you have claimed the opposite of what follows from
>>>> Maxwell’s equations, namely that the isotropy of the speed of light would
>>>> merely be an assumption (instead of an experimental fact).
>>> 
>>> The Constancy of the speed of light was an assumption made by Einstein
>>> to develop special relativity.
>> 
>> Which is in fact redundant, given the principle of relativity applied to
>> electrodynamics.
> 
> Einstein didn't know it at the time.

Actually, he did.  That’s the section of the 1905 paper where he formulates
the covariant form of the electromagnetic field. Kinda the point. 

>  Nobody did, which was the whole 
> question of the age. Glad to see that you have now won the "who is 
> smarter than Einstein" contest again. Maybe you should argue like Mr. 
> Vulcan that Einstein never said it. You've read all his books and papers.
> 
>>> 
>>>> While it follows from Maxwell’s equations that which is an experimental
>>>> fact, namely that the speed of light c is isotropic as it only depends on
>>>> the electromagnetic properties of the medium through which (Maxwell’s)
>>>> electromagnetic waves, such as light, travel:
>>>> 
>>>> c = 1/√(ε₀ ε_r µ₀ µ_r).
>>>> 
>>>> So, are you retracting that claim?
>>> 
>>> However "[one can] develop relativistic electromagnetism solely on the
>>> basis of electromagnetic retardation and the principle of [Galilean]
>>> relativity without any additional postulates, hypotheses, or conjectures."
>>> 
>>> 
>>> 
>> 
>> 
>> 
> 
> 



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

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#476279

On 11/4/2018 10:00 PM, Odd Bodkin wrote:
> benj <benj.fake@gmail.com> wrote:
>> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>>> benj <benj.fake@gmail.com> wrote:
>>>> On 11/4/2018 2:01 PM, Thomas 'PointedEars' Lahn wrote:
>>>>> benj wrote:
>>>>>
>>>>>> Wake up dumbass. You can prove E=mc² from Maxwell's equations.
>>>>>
>>>>> No, but you can be _deduced_ from that, assuming that the special principle
>>>>> of relativity holds.  That is precisely what Einstein did in his second
>>>>> (“annus mirabilis”) 1905 paper on what became special relativity, “Does the
>>>>> Inertia of a Body Depend Upon Its Energy Content?”:
>>>>>
>>>>> <https://einsteinpapers.press.princeton.edu/vol2-trans/186>
>>>>>
>>>>> Later, in 1929, Paul Dirac showed that it – and more generally, the
>>>>> energy–momentum relation – can be derived from the properties of flat
>>>>> spacetime alone:
>>>>>
>>>>> With
>>>>>
>>>>> p⃗    = γ m v⃗ = γ m (v_x, v_y, v_z)
>>>>> P⃗    = (E/c, p⃗) = γ m (c, v⃗)
>>>>> ||P⃗||² = (E/c)² − p⃗² = m²c²
>>>>>
>>>>> one finds
>>>>>
>>>>> E² = m²c⁴ + p⃗²c²
>>>>>
>>>>> which gives for the *rest* energy (when v⃗ = 0)
>>>>>
>>>>> E₀ = m c².
>>>>>
>>>>> <https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relation>
>>>>>
>>>>>> Exponent is squared.
>>>>>
>>>>> Correct.
>>>>>
>>>>> However, previously you have claimed the opposite of what follows from
>>>>> Maxwell’s equations, namely that the isotropy of the speed of light would
>>>>> merely be an assumption (instead of an experimental fact).
>>>>
>>>> The Constancy of the speed of light was an assumption made by Einstein
>>>> to develop special relativity.
>>>
>>> Which is in fact redundant, given the principle of relativity applied to
>>> electrodynamics.
>>
>> Einstein didn't know it at the time.
> 
> Actually, he did.  That’s the section of the 1905 paper where he formulates
> the covariant form of the electromagnetic field. Kinda the point.

Boinker how can one seemingly articulate person be such a dumbass?
The point of the paper was to answer the question which everyone had at 
the time. You just turn it all upside down and call it sane. so your 
sane argument is he knew it was true before he proved it? You are such a 
fool Boinker.


>>   Nobody did, which was the whole
>> question of the age. Glad to see that you have now won the "who is
>> smarter than Einstein" contest again. Maybe you should argue like Mr.
>> Vulcan that Einstein never said it. You've read all his books and papers.
>>
>>>>
>>>>> While it follows from Maxwell’s equations that which is an experimental
>>>>> fact, namely that the speed of light c is isotropic as it only depends on
>>>>> the electromagnetic properties of the medium through which (Maxwell’s)
>>>>> electromagnetic waves, such as light, travel:
>>>>>
>>>>> c = 1/√(ε₀ ε_r µ₀ µ_r).
>>>>>
>>>>> So, are you retracting that claim?
>>>>
>>>> However "[one can] develop relativistic electromagnetism solely on the
>>>> basis of electromagnetic retardation and the principle of [Galilean]
>>>> relativity without any additional postulates, hypotheses, or conjectures."
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>
>>
> 
> 
> 

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#476301

benj <benj.fake@gmail.com> wrote:
> On 11/4/2018 10:00 PM, Odd Bodkin wrote:
>> benj <benj.fake@gmail.com> wrote:
>>> On 11/4/2018 5:14 PM, Odd Bodkin wrote:
>>>> benj <benj.fake@gmail.com> wrote:
>>>>> On 11/4/2018 2:01 PM, Thomas 'PointedEars' Lahn wrote:
>>>>>> benj wrote:
>>>>>> 
>>>>>>> Wake up dumbass. You can prove E=mc² from Maxwell's equations.
>>>>>> 
>>>>>> No, but you can be _deduced_ from that, assuming that the special principle
>>>>>> of relativity holds.  That is precisely what Einstein did in his second
>>>>>> (“annus mirabilis”) 1905 paper on what became special relativity, “Does the
>>>>>> Inertia of a Body Depend Upon Its Energy Content?”:
>>>>>> 
>>>>>> <https://einsteinpapers.press.princeton.edu/vol2-trans/186>
>>>>>> 
>>>>>> Later, in 1929, Paul Dirac showed that it – and more generally, the
>>>>>> energy–momentum relation – can be derived from the properties of flat
>>>>>> spacetime alone:
>>>>>> 
>>>>>> With
>>>>>> 
>>>>>> p⃗    = γ m v⃗ = γ m (v_x, v_y, v_z)
>>>>>> P⃗    = (E/c, p⃗) = γ m (c, v⃗)
>>>>>> ||P⃗||² = (E/c)² − p⃗² = m²c²
>>>>>> 
>>>>>> one finds
>>>>>> 
>>>>>> E² = m²c⁴ + p⃗²c²
>>>>>> 
>>>>>> which gives for the *rest* energy (when v⃗ = 0)
>>>>>> 
>>>>>> E₀ = m c².
>>>>>> 
>>>>>> <https://en.wikipedia.org/wiki/Energy%E2%80%93momentum_relation>
>>>>>> 
>>>>>>> Exponent is squared.
>>>>>> 
>>>>>> Correct.
>>>>>> 
>>>>>> However, previously you have claimed the opposite of what follows from
>>>>>> Maxwell’s equations, namely that the isotropy of the speed of light would
>>>>>> merely be an assumption (instead of an experimental fact).
>>>>> 
>>>>> The Constancy of the speed of light was an assumption made by Einstein
>>>>> to develop special relativity.
>>>> 
>>>> Which is in fact redundant, given the principle of relativity applied to
>>>> electrodynamics.
>>> 
>>> Einstein didn't know it at the time.
>> 
>> Actually, he did.  That’s the section of the 1905 paper where he formulates
>> the covariant form of the electromagnetic field. Kinda the point.
> 
> Boinker how can one seemingly articulate person be such a dumbass?
> The point of the paper was to answer the question which everyone had at 
> the time. You just turn it all upside down and call it sane. so your 
> sane argument is he knew it was true before he proved it? You are such a 
> fool Boinker.

What he wrote is not how he discovered it. It’s how he presented it. He
knew the results of the last section before he chose how to write the first
section. Idiot. 

> 
> 
>>> Nobody did, which was the whole
>>> question of the age. Glad to see that you have now won the "who is
>>> smarter than Einstein" contest again. Maybe you should argue like Mr.
>>> Vulcan that Einstein never said it. You've read all his books and papers.
>>> 
>>>>> 
>>>>>> While it follows from Maxwell’s equations that which is an experimental
>>>>>> fact, namely that the speed of light c is isotropic as it only depends on
>>>>>> the electromagnetic properties of the medium through which (Maxwell’s)
>>>>>> electromagnetic waves, such as light, travel:
>>>>>> 
>>>>>> c = 1/√(ε₀ ε_r µ₀ µ_r).
>>>>>> 
>>>>>> So, are you retracting that claim?
>>>>> 
>>>>> However "[one can] develop relativistic electromagnetism solely on the
>>>>> basis of electromagnetic retardation and the principle of [Galilean]
>>>>> relativity without any additional postulates, hypotheses, or conjectures."
>>>>> 
>>>>> 
>>>>> 
>>>> 
>>>> 
>>>> 
>>> 
>>> 
>> 
>> 
>> 
> 
> 



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

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#476346

Thomas 'PointedEars' Lahn wrote:

> While it follows from Maxwell’s equations that which is an experimental
> fact, namely that the speed of light c is isotropic as it only depends
> on the electromagnetic properties of the medium through which
> (Maxwell’s) electromagnetic waves, such as light, travel:
>   c = 1/√(ε₀ ε_r µ₀ µ_r).

You can't. Light cannot travel through a medium which is opaque. That 
formulae is nill. You are just giving another proof.

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#476965

The ’nym-shifting troll trolled as "Buck Dehner" <uktea@yswdoiz.cp>
(invalid TLD):

> Thomas 'PointedEars' Lahn wrote:
>> While it follows from Maxwell’s equations that which is an experimental
>> fact, namely that the speed of light c is isotropic as it only depends
>> on the electromagnetic properties of the medium through which
>> (Maxwell’s) electromagnetic waves, such as light, travel:
>>   c = 1/√(ε₀ ε_r µ₀ µ_r).
> 
> You can't. Light cannot travel through a medium which is opaque. That 
> formulae is nill. You are just giving another proof.

There is absolutely nothing in the above that suggests an opaque medium.

It is only the ’nym-shifting troll.  *PLONK*

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#476994

the severely uneducated homepage designer Thomas 'PointedEars' Lahn wrote:

> Honourable Dr. Buck Dehner <uktea@yswdoiz.cp>
> 
>> Thomas 'PointedEars' Lahn wrote:
>>> While it follows from Maxwell’s equations that which is an
>>> experimental fact, namely that the speed of light c is isotropic as it
>>> only depends on the electromagnetic properties of the medium through
>>> which (Maxwell’s) electromagnetic waves, such as light, travel:
>>>   c = 1/√(ε₀ ε_r µ₀ µ_r).
>> 
>> You can't. Light cannot travel through a medium which is opaque. That
>> formulae is nill. You are just giving another proof.
> 
> There is absolutely nothing in the above that suggests an opaque medium.
> 
> It is only the ’nym-shifting troll.  *PLONK*

This homepage designer, once again, is not knowing the symbols he grabbed 
from wikipedia and whoknowswhere. An (ε₀ ε_r µ₀ µ_r) characterize ANY 
medium, my friend. You made me feel depressed.

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#477005

The ’nym-shifting troll demonstrated their ignorance as "Gaston Castaneda"
<uucp@jav4ow.nq> (invalid TLD):

> the severely uneducated homepage designer Thomas 'PointedEars' Lahn wrote:

JFTR: I am not a "homepage designer", but a professional, employed (mostly
Web) software developer with a BSc in Computer Science, now also studying
for BSc in Physics with minor in Astronomy (who happens to have a private
Web site, too).  Google me.

>> Honourable Dr. Buck Dehner <uktea@yswdoiz.cp>
   ^^^^^^^^^^^^^^
LOL.  That is *you*.  It would seem that your stupidity knows no limits.
How stupid do you think we are so that we would not realize that this is a
sockpuppet scheme on your part?

>>> Thomas 'PointedEars' Lahn wrote:
>>>> While it follows from Maxwell’s equations that which is an
>>>> experimental fact, namely that the speed of light c is isotropic as it
>>>> only depends on the electromagnetic properties of the medium through
>>>> which (Maxwell’s) electromagnetic waves, such as light, travel:
>>>>   c = 1/√(ε₀ ε_r µ₀ µ_r).
>>> You can't. Light cannot travel through a medium which is opaque. That
>>> formulae is nill. You are just giving another proof.
>>
>> There is absolutely nothing in the above that suggests an opaque medium.
> […]
> […] An (ε₀ ε_r µ₀ µ_r) characterize ANY medium, my friend.

Including vacuum/no medium, where ε_r = µ_r = 1 and c = c₀
= 299'792'458 m/s.

Again, none of this suggests opaqueness; however, as even mildly educated
people know, electromagnetic waves do travel through media that are opaque
to visible light, for example microwaves, radio waves, X-ray, and gamma
radiation.

> You made me feel depressed.

Some education on your part might solve this problem.  As an alternative,
FOAD instead of continuing to read, and post to, a newsgroup for whose
subjects you do not have the brains.

Also, not constantly violating the Usenet rules of conduct (Netiquette) and
technical standards (RFC 5536) all of which will eventually either get you
kicked from aioe.org or land you in a sufficient number of killfiles so that
*nobody* will read your postings anymore (whichever  will happen first;
there is a *finite* number of random “From” "addresses" that you can choose
from, which you would know if you had any clue about anything, in particular
computer science).  If that is what you really want, keep on posting like that.

*PLONK*

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#477072

Thomas 'PointedEars' Lahn wrote:

> Also, not constantly violating the Usenet rules of conduct (Netiquette)
> and technical standards (RFC 5536) all of which will eventually either
> get you kicked from aioe.org or land you in a sufficient number of
> killfiles

Ohh my gosh, everything but RFC 5536. Please choose another RFC.

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#476345

benj wrote:

> On 11/4/2018 7:34 AM, Buck Dehner wrote:
>> Sylvia Else wrote:
>> 
>>> On 2/11/2018 8:43 am, Omar Shabsigh wrote:
>>>>    I was not convinced by the derivation of this formula whether by
>>>>    Einstein or others. HELP!!!!!!
>>>>
>>>>
>>> You haven't provided much information. You might have an issue with
>>> the postulates or with the algebra. Or you might just have a
>>> philosophical objection that is incapable of being addressed by any
>>> kind of argument.
>>> It is generally accepted that the algebra is correct, and the
>>> resulting formula fits experimental results.
>> 
>> Negative. E=mc² is invalid from head to tail. Based entirely on
>> circular reasoning and assumed assertions. When you can prove that
>> E=/=mc³ or that E=/=mc^1.6 wake me up.
>> 
> Wake up dumbass. You can prove E=mc² from Maxwell's equations. Exponent
> is squared

Hey listen, it might come as a surprise to you, but Maxwell based his 
stuff on rotating rigid hexagons (to fill the space). It's a mechanism. 
Hexagons are circular.

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#476541

On Sunday, November 4, 2018 at 10:17:38 AM UTC-8, benj wrote:
> On 11/4/2018 7:34 AM, Buck Dehner wrote:
> > Sylvia Else wrote:
> > 
> >> On 2/11/2018 8:43 am, Omar Shabsigh wrote:
> >>>    I was not convinced by the derivation of this formula whether by
> >>>    Einstein or others. HELP!!!!!!
> >>>
> >>>
> >> You haven't provided much information. You might have an issue with the
> >> postulates or with the algebra. Or you might just have a philosophical
> >> objection that is incapable of being addressed by any kind of argument.
> >> It is generally accepted that the algebra is correct, and the resulting
> >> formula fits experimental results.
> > 
> > Negative. E=mc² is invalid from head to tail. Based entirely on circular
> > reasoning and assumed assertions. When you can prove that E=/=mc³ or that
> > E=/=mc^1.6 wake me up.
> > 
> Wake up dumbass. You can prove E=mc² from Maxwell's equations. Exponent 
> is squared.



Well, not quite. All Maxwell's equations gives you is that momentum of light p = E/c.

However you can go further with some assumptions. If you have a tube of mass M and length L floating in space, you can investigate what happens when somebody inside the tube throws a small mass m down the tube to hit at the other end. Think of a tube-shaped rocket with a guy at one end throwing a baseball m (the mobile mass) from one end to the other.

In general it's easy to show that the center of mass of the tube does not change while the mobile mass m is in motion, but rather what happens is that a small part of the tube deltaM crosses the line of the old center-of-mass while the small m is in flight, and when the mass m hits the other end, the tube stops moving. The amount of tube deltaM over the line is equal to the thrown mass m that went from one end the other, and if you calculate from conservation of momentum how much that is, deltaM = m so that mass on both sides of the center-of-mass line stays equal, even though the tube moves from side to side while the ball is in motion. 

All this is true no matter how small m is, or how fast it goes (v). If you raise v, all that happens is the tube moves faster, more mass crosses the mid-line in the time allowed, and deltaM stays the same no matter what v is! 

Now you'd like to do the gedanken of what happens if the "baseball" is a particle of light (photon). If you could calculate deltaM for the tube moving across the center of mass line with the photon in flight, that would be the equivalent mass of the particle of light, because that much mass would have moved from one end of the tube to the other with the translocation of the photon (instead of the baseball). And you can do that. 

If you use a photon with p = E/c as in Maxwell, then the tube mass deltaM has time L/c to cross the line while its momentum is p = Mv. Thus distance moved delta-L = vt = p/M * L/c = pL/Mc. Since deltaM = [M/L] delta-L we have 

deltaM = [M/L] [pL/Mc] = p/c.

But deltaM is tangible mass of the pipe! If it's p/c of the photon going down it, and that p is Maxwell's E/c then deltaM = [E/c] = E/c^2.

That's Einstein's result, but we haven't used any of his special relativity at all. This is just Newtonian mechanics with the assumption of conservation of momentum, and the novel Maxwell result that for photons p = E/c. The whole E = mc^2 thing is already in Maxwell's p = E/c, although it's hard to see it. But Einstein certainly pulled it out the hard way. You don't need ANY of his relativity paper to do it. I just did it.
  

 

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#476542

On Sunday, November 4, 2018 at 10:17:38 AM UTC-8, benj wrote:
> On 11/4/2018 7:34 AM, Buck Dehner wrote:
> > Sylvia Else wrote:
> > 
> >> On 2/11/2018 8:43 am, Omar Shabsigh wrote:
> >>>    I was not convinced by the derivation of this formula whether by
> >>>    Einstein or others. HELP!!!!!!
> >>>
> >>>
> >> You haven't provided much information. You might have an issue with the
> >> postulates or with the algebra. Or you might just have a philosophical
> >> objection that is incapable of being addressed by any kind of argument.
> >> It is generally accepted that the algebra is correct, and the resulting
> >> formula fits experimental results.
> > 
> > Negative. E=mc² is invalid from head to tail. Based entirely on circular
> > reasoning and assumed assertions. When you can prove that E=/=mc³ or that
> > E=/=mc^1.6 wake me up.
> > 
> Wake up dumbass. You can prove E=mc² from Maxwell's equations. Exponent 
> is squared.

Well, not quite. All Maxwell's equations gives you is that momentum of light p = E/c.

However you can go further with some assumptions. If you have a tube of mass M and length L floating in space, you can investigate what happens when somebody inside the tube throws a small mass m down the tube to hit at the other end. Think of a tube-shaped rocket with a guy at one end throwing a baseball m (the mobile mass) from one end to the other.

In general it's easy to show that the center of mass of the tube does not change while the mobile mass m is in motion, but rather what happens is that a small part of the tube deltaM crosses the line of the old center-of-mass while the small m is in flight, and when the mass m hits the other end, the tube stops moving. The amount of tube deltaM over the line is equal to the thrown mass m that went from one end the other, and if you calculate from conservation of momentum how much that is, deltaM = m so that mass on both sides of the center-of-mass line stays equal, even though the tube moves from side to side while the ball is in motion.

All this is true no matter how small m is, or how fast it goes (v). If you raise v, all that happens is the tube moves faster, more mass crosses the mid-line in the time allowed, and deltaM stays the same no matter what v is!

Now you'd like to do the gedanken of what happens if the "baseball" is a particle of light (photon). If you could calculate deltaM for the tube moving across the center of mass line with the photon in flight, that would be the equivalent mass of the particle of light, because that much mass would have moved from one end of the tube to the other with the translocation of the photon (instead of the baseball). And you can do that.

If you use a photon with p = E/c as in Maxwell, then the tube mass deltaM has time L/c to cross the line while its momentum is p = Mv. Thus distance moved delta-L = vt = p/M * L/c = pL/Mc. Since deltaM = [M/L] delta-L we have

deltaM = [M/L] [pL/Mc] = p/c.

But deltaM is tangible mass of the pipe! If it's p/c of the photon going down it, and that p is Maxwell's E/c then deltaM = [E/c]/c = E/c^2.

That's Einstein's result, but we haven't used any of his special relativity at all. This is just Newtonian mechanics with the assumption of conservation of momentum, and the novel Maxwell result that for photons p = E/c. The whole E = mc^2 thing is already in Maxwell's p = E/c, although it's hard to see it. But Einstein certainly pulled it out the hard way. You don't need ANY of his relativity paper to do it. I just did it.
 

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#476551

Steve BH escrito 

Well, not quite. All Maxwell's equations gives you is that momentum of light p = E/c. 

However you can go further with some assumptions. If you have a tube of mass M and length L floating in space, you can investigate what happens when somebody inside the tube throws a small mass m down the tube to hit at the other end. Think of a tube-shaped rocket with a guy at one end throwing a baseball m (the mobile mass) from one end to the other. 

In general it's easy to show that the center of mass of the tube does not change while the mobile mass m is in motion, but rather what happens is that a small part of the tube deltaM crosses the line of the old center-of-mass while the small m is in flight, and when the mass m hits the other end, the tube stops moving. The amount of tube deltaM over the line is equal to the thrown mass m that went from one end the other, and if you calculate from conservation of momentum how much that is, deltaM = m so that mass on both sides of the center-of-mass line stays equal, even though the tube moves from side to side while the ball is in motion. 

All this is true no matter how small m is, or how fast it goes (v). If you raise v, all that happens is the tube moves faster, more mass crosses the mid-line in the time allowed, and deltaM stays the same no matter what v is! 

Now you'd like to do the gedanken of what happens if the "baseball" is a particle of light (photon). If you could calculate deltaM for the tube moving across the center of mass line with the photon in flight, that would be the equivalent mass of the particle of light, because that much mass would have moved from one end of the tube to the other with the translocation of the photon (instead of the baseball). And you can do that. 

If you use a photon with p = E/c as in Maxwell, then the tube mass deltaM has time L/c to cross the line while its momentum is p = Mv. Thus distance moved delta-L = vt = p/M * L/c = pL/Mc. Since deltaM = [M/L] delta-L we have 

deltaM = [M/L] [pL/Mc] = p/c. 

But deltaM is tangible mass of the pipe! If it's p/c of the photon going down it, and that p is Maxwell's E/c then deltaM = [E/c]/c = E/c^2. 

That's Einstein's result, but we haven't used any of his special relativity at all. This is just Newtonian mechanics with the assumption of conservation of momentum, and the novel Maxwell result that for photons p = E/c. The whole E = mc^2 thing is already in Maxwell's p = E/c, although it's hard to see it. But Einstein certainly pulled it out the hard way. You don't need ANY of his relativity paper to do it. I just did it


You just explained (Bulk Modulus & Wave Speed in a medium)

https://docs.google.com/document/d/14dGOjOuRXXIBSg-0N-vBovhwDCnrMbBioONasYH9FG0

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#476262

On 4/11/2018 11:34 pm, Buck Dehner wrote:
> Sylvia Else wrote:
> 
>> On 2/11/2018 8:43 am, Omar Shabsigh wrote:
>>>    I was not convinced by the derivation of this formula whether by
>>>    Einstein or others. HELP!!!!!!
>>>
>>>
>> You haven't provided much information. You might have an issue with the
>> postulates or with the algebra. Or you might just have a philosophical
>> objection that is incapable of being addressed by any kind of argument.
>> It is generally accepted that the algebra is correct, and the resulting
>> formula fits experimental results.
> 
> Negative. E=mc² is invalid from head to tail. Based entirely on circular
> reasoning and assumed assertions. When you can prove that E=/=mc³ or that
> E=/=mc^1.6 wake me up.
> 

I think this betrays a lack of understanding of what physics is about.

So far, we have no reason to think that we can deduce the laws of the 
universe from first principles. If we could, that would imply that only 
one set of laws is conceivable.

Instead, we make observations of how the universe behaves, and try to 
fit those observations into a mathematical framework that allows us to 
predict the results of observations that have not yet been made.

Einstein looked at the laws of electromagnetism, and formed the view 
that they suggested that the laws of physics depend only on relative 
motion. One ramification of that would be the observed constancy of the 
speed of light. He then showed that this hypothesis leads to a number of 
conclusions, of which E = mc^2 is one. The exponent of two arises 
inexorably from the algebra. No other exponent can be derived that way. 
If the correct exponent is other than two, then the hypothesis must be 
wrong. As has already been pointed out, any exponent other than two 
would also raise the problem that the equation would be dimensionally 
inconsistent.

The hypothesis might indeed have been wrong. If it were, one would 
expect one or more of the conclusions to be found to be false. So far 
they have not been. In particular, E = mc^2 stands up very well.

Sylvia.

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