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Relative motion again

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  Relative motion again xip1415926@gmail.com - 2018-11-05 10:49 -0800
    Re:Relative motion again Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-05 20:16 +0100
      Re:Relative motion again Buck Dehner <uktea@yswdoiz.cp> - 2018-11-05 21:07 +0000
        Re:Relative motion again Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-05 22:55 +0100
          Re:Relative motion again Buck Dehner <uktea@yswdoiz.cp> - 2018-11-05 22:46 +0000
            Re:Relative motion again Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-06 01:22 +0100
              Re:Relative motion again Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-06 20:27 +0000
    Re: Relative motion again Sylvia Else <sylvia@email.invalid> - 2018-11-06 13:16 +1100
      Re: Relative motion again benj <benj.fake@gmail.com> - 2018-11-05 21:45 -0500
        Re: Relative motion again Sylvia Else <sylvia@email.invalid> - 2018-11-06 14:57 +1100
      Re: Relative motion again xip1415926@gmail.com - 2018-11-05 19:58 -0800
        Re: Relative motion again xip1415926@gmail.com - 2018-11-05 21:24 -0800
        Re: Relative motion again Sylvia Else <sylvia@email.invalid> - 2018-11-06 18:10 +1100
        Re: Relative motion again Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-06 09:21 +0100
          Re: Relative motion again xip1415926@gmail.com - 2018-11-06 06:03 -0800
            Re: Relative motion again Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-06 08:41 -0600
              Re: Relative motion again Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-06 20:32 +0000
                Re: Relative motion again Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-06 20:39 -0600
                  Re: Relative motion again Ntowicz Usarczyk <iswso@wioioksi.io> - 2018-11-07 19:44 +0000
            Re: Relative motion again Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-06 22:32 +0100

#476337 — Relative motion again

Some guy walks out of a bar…

Well, almost.

Actually, two guys walk out of two bars, these guys being of about equal weight, mass = 150 lbs, and equal walking speed, 2 mph. They turn right and left on leaving doorways, thereby approaching each other on the sidewalk. 

Walker-A has speed a = 2 and walker-B has speed b = 2, speeds conveniently positive though of opposite directions.

Relative motion of the walkers is convergence.  Walkers A and B approach one another with speed v = a + b = 2 + 2 = 4.

Other models will deliver convergence speed v = 4, for example walker-A hustles at sidewalk speed a = 4 and walker-B remains standing, b = 0, hence v = 4 + 0 = 4; alternatively a = 0 and b = 4 hence v = 0 + 4 = 4

It should be noted that v = a + b is a classroom formula: the teacher must know both of a and b.  Walkers A and B themselves would not normally know each of a and b.   

Now our walkers have had a few, are not paying close attention, and collide.  

Their discomfort level at the moment of collision depends only on v = 4.  

Consult Wiki: Inelastic Collision

Meanwhile, prior to impact, the sidewalk is witness to kinetic energy, it being in total:

KE = ½ · m · a² + ½ · m · b² = ½ · 150 · a² + ½ · 150 · b²

Total kinetic energy on the sidewalk depends on the distribution of speed v between a and b, in particular, if a = b = 2 ie, v = 2 + 2 = 4, total KE is one half of a situation where a = 4 and b = 0, ie v = 4 + 0 = 4.

Discomfort level does not depend on the distribution of speed v between a and b.

Now suppose walker-A has a microphone and walker-B has an audio oscillator.  Walker-A will detect on his microphone some frequency slightly higher than the natural frequency of B’s oscillator.  This is normal Doppler shift, more particularly ‘blue shift’ since we have speed of approach ( convergence ).

The medium of signal transmission, the air, is necessarily stationary with respect to the sidewalk.  

Consult Wiki: Doppler Shift.

F is frequency detected by walker-A, the microphone guy.

f is frequency of the audio oscillator held by walker-B.

s is the speed of sound in air which air is stationary on the sidewalk.

Case #1: Walker-A has speed a = 4 and walker-B has speed b = 0.

Case #2: Walker-A has speed a = 0 and walker-B has speed b = 4.

Relative motion is v = 4 in both cases #1 and #2.

Formula #1: a = 4, b = 0:  F = [ ( s + 4 ) / s ] · f

Formula #2: a = 0, b = 4:  F = [ s / ( s – 4 ) ] · f

Formulas #1 and #2 are perfectly good Newtonian kinematics.  

Two formulas are natural dualism.  One walker is stationary on the sidewalk and all of convergence speed v = 4 is vested in the other walker.   It’s reasonable to suppose that frequency F versus f, detected by the microphone, should depend on the assignment of motion to the microphone ( case #1 ) or to the oscillator ( case #2 ).

Suppose next that walker-A detects not the frequency of sound but the speed of sound, speed relative to his own platform, not relative to the air.

Speed of sound in the fixed medium, relative to the air, is s.   Reasonably then, detected speed on the platform of walker-A is s in mode #1 and s + v in mode #2, since in mode #2 walker-A has speed v in the air, and v adds to s in the air, generated by walker-B.

Speed of sound is then not fixed at s.  Speed of sound depends on the configuration of relative motion.  How does Special Relativity deliver speed of light equal to c in all configurations?

SRT gets rid of the  “luminiferous ether”, which medium of transmission is analogous to air used by sound.  Walker-B sends laser signals towards walker-A.   Propagation of light is now some mysterious non-Newtonian phenomenon and walker-A detects speed c whether he has case #1 or case #2.

In EDoMB-1905 it is otherwise.  EDoMB imposes one condition on walker-A:  If walker-A detects the speed of light on his platform, his platform is always stationary.  He has only case #2, never case #1. 

EDoMB is explicit.  Quote:  “The introduction of a luminiferous ether will prove to be superfluous inasmuch as the view here to be developed will not require an absolutely stationary space provided with special properties.”

Quote:  “Phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the idea of absolute rest.” 

Quote: “In order to render our presentation more precise and to distinguish this system of co-ordinates verbally from others which will be introduced hereafter, we call it the stationary system.”

Summary: While walker-A is never at “absolute rest” in the universe, in any situation of relative motion he is entitled to assign all of relative motion to the counterparty, and in that sense he is “stationary”, which is to say his stance is always case #2, never case #1.

Elimination of case #1 much simplifies the situation.  Walker-A, when he is observer or judge of speed of light on his platform, has only one point of view.

Thus, walker-A resides on a “stationary” platform and there he evaluates a ray of light which is sent out by relatively moving walker-B.    According to ordinary projectile motion ( which is not convection in a medium ) light speed on platform-A is either c + v or c – v.  How is it that light speed known to walker-A is always c regardless of relative speed v of light-source walker-B?

Einstein does not answer this question directly.

A very ambiguous business is at hand.  Suppose stationary guy-A sends a ray of light to relatively moving platform-B, and projectile motion on platform-B is detected as c + v or c – v.   Since platform-B is moving, its clocks and meter sticks are governed by the Lorentz Transforms, formulae which depend on motion v.  It is possible to adjust B’s clocks and meter sticks such as to convert speed c + v or c – v into speed c; again on moving platform B.

That is not EDoMB Sections 1 and 2. 

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#476338

xip1415926@gmail.com Wrote in message:
Technical note: Speed and distance cannot be negative.

-- 
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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#476348

Libor Striz wrote:

> xip1415926@gmail.com Wrote in message:
> Technical note: Speed and distance cannot be negative.

You have it upside down, my polish friend. The velocity and the position 
cannot be negative, since those are vectors with angles attached, making 
the negativity obsolete, deprecated and superfluous.

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#476352

Buck Dehner <uktea@yswdoiz.cp> Wrote in message:
> Libor Striz wrote:> xip1415926@gmail.com Wrote in message:

>> Technical note: Speed and distance cannot be negative.

> You have it upside down, my polish friend. The velocity and the position cannot be negative, since those are vectors with angles attached, making the negativity obsolete, deprecated and superfluous.

I am not polish.

Velocity and position cannot be negative, but their components can.





-- 
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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#476354

Libor Striz wrote:

> Buck Dehner <uktea@yswdoiz.cp> Wrote in message:
>> Libor Striz wrote:> xip1415926@gmail.com Wrote in message:
> 
>>> Technical note: Speed and distance cannot be negative.
> 
>> You have it upside down, my polish friend. The velocity and the
>> position cannot be negative, since those are vectors with angles
>> attached, making the negativity obsolete, deprecated and superfluous.
> 
> I am not polish.
> Velocity and position cannot be negative, but their components can.

It can't, it would be physically impossible, being both not negative and 
negative same time. And what's wrong in being polish?

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#476361

Buck Dehner <uktea@yswdoiz.cp> Wrote in message:
> Libor Striz wrote:> Buck Dehner <uktea@yswdoiz.cp> Wrote in message:

>> I am not polish.

>> Velocity and position cannot be negative, but their components can.

>> It can't, it would be physically impossible, being both not negative and negative same time. And what's wrong in being polish?

Not only being a boring nymshifting troll, but you cannot even
 read properly.

Nothing wrong in being polish. Definitely better than being a
 nymshifting troll.

Speed cannot be negative, velocity components can.



-- 
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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#476435

On Tue, 06 Nov 2018 01:22:56 +0100, Libor Striz wrote:

> Buck Dehner <uktea@yswdoiz.cp> Wrote in message:
>> Libor Striz wrote:> Buck Dehner <uktea@yswdoiz.cp> Wrote in message:
> 
>>> I am not polish.
> 
>>> Velocity and position cannot be negative, but their components can. 
>>> It can't, it would be physically impossible, being both not negative
>>> and negative same time. And what's wrong in being polish?
> 
> Not only being a boring nymshifting troll, but you cannot even
>  read properly.

I am just reading here to see that you can't read what you just said?

"Velocity and position cannot be negative, but their components can."

This is absurd, and you must be that "nymshifting troll". As saying your 
bodyparts are antimater, and your body matter. Absurd, especially in math 
and physics. And in everything else as well.

And you hate the polish, saying that you don't want to be a one, by "I am 
not polish".

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#476365

On 6/11/2018 5:49 am, xip1415926@gmail.com wrote:
> Some guy walks out of a bar…
> 
> Well, almost.
> 
> Actually, two guys walk out of two bars, these guys being of about equal weight, mass = 150 lbs, and equal walking speed, 2 mph. They turn right and left on leaving doorways, thereby approaching each other on the sidewalk.
> 
> Walker-A has speed a = 2 and walker-B has speed b = 2, speeds conveniently positive though of opposite directions.
> 
> Relative motion of the walkers is convergence.  Walkers A and B approach one another with speed v = a + b = 2 + 2 = 4.
> 

This is wrong. You are making the unfounded assumption that velocities 
combine by addition, when they do not. The difference is negligible for 
small velocities, but large when the magnitudes of the velocities 
approach the speed of light.

Sylvia.

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#476367

On 11/5/2018 9:16 PM, Sylvia Else wrote:
> On 6/11/2018 5:49 am, xip1415926@gmail.com wrote:
>> Some guy walks out of a bar…
>>
>> Well, almost.
>>
>> Actually, two guys walk out of two bars, these guys being of about 
>> equal weight, mass = 150 lbs, and equal walking speed, 2 mph. They 
>> turn right and left on leaving doorways, thereby approaching each 
>> other on the sidewalk.
>>
>> Walker-A has speed a = 2 and walker-B has speed b = 2, speeds 
>> conveniently positive though of opposite directions.
>>
>> Relative motion of the walkers is convergence.  Walkers A and B 
>> approach one another with speed v = a + b = 2 + 2 = 4.
>>
> 
> This is wrong. You are making the unfounded assumption that velocities 
> combine by addition, when they do not. The difference is negligible for 
> small velocities, but large when the magnitudes of the velocities 
> approach the speed of light.
> 
> Sylvia.

You are simply wrong Sylvia. By the principle of Galilean relativity, if 
the two guys walk out of the bar and approach each other it would not 
matter if both of them were traveling near the speed of light. To each 
other they would be traveling slow. But to an observer across the street 
things would appear quite different. And the reason would be retardation 
not relativity. Or do you believe as they approach the speed of light 
the sidewalk shortens?

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#476373

On 6/11/2018 1:45 pm, benj wrote:
> On 11/5/2018 9:16 PM, Sylvia Else wrote:
>> On 6/11/2018 5:49 am, xip1415926@gmail.com wrote:
>>> Some guy walks out of a bar…
>>>
>>> Well, almost.
>>>
>>> Actually, two guys walk out of two bars, these guys being of about 
>>> equal weight, mass = 150 lbs, and equal walking speed, 2 mph. They 
>>> turn right and left on leaving doorways, thereby approaching each 
>>> other on the sidewalk.
>>>
>>> Walker-A has speed a = 2 and walker-B has speed b = 2, speeds 
>>> conveniently positive though of opposite directions.
>>>
>>> Relative motion of the walkers is convergence.  Walkers A and B 
>>> approach one another with speed v = a + b = 2 + 2 = 4.
>>>
>>
>> This is wrong. You are making the unfounded assumption that velocities 
>> combine by addition, when they do not. The difference is negligible 
>> for small velocities, but large when the magnitudes of the velocities 
>> approach the speed of light.
>>
>> Sylvia.
> 
> You are simply wrong Sylvia. By the principle of Galilean relativity, if 
> the two guys walk out of the bar and approach each other it would not 
> matter if both of them were traveling near the speed of light. To each 
> other they would be traveling slow. But to an observer across the street 
> things would appear quite different. And the reason would be retardation 
> not relativity. Or do you believe as they approach the speed of light 
> the sidewalk shortens?

If they're both travelling near the speed of light relative to the 
street in the same direction, but one is travelling slightly faster than 
the other relative to the street, then that would be true.

The OP's scenario relates to two people travelling in opposite 
directions relative to the street, and the OP then seeks to deduce the 
speed of one person relative to the other, and does so incorrectly based 
on the assumption that velocities combine by addition.

Sylvia

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#476374

On Monday, November 5, 2018 at 9:16:07 PM UTC-5, Sylvia Else wrote:

> This is wrong. You are making the unfounded assumption that velocities 
> combine by addition, when they do not. The difference is negligible for 
> small velocities, but large when the magnitudes of the velocities 
> approach the speed of light.
> 
> Sylvia.

You are talking about relativistic addition of velocities:

v = [ a + b ] / [ 1 + ( a · b ) / c² ] 

When a and b are each approximately equal to c you have:

v = [ c + c ] / 2 = c

The problem at hand has nothing to do with this.  Problem:  In a junior high school science class, under what circumstances does v exist at all ???  As I pointed out v = a + b exists only for the teacher at the blackboard and does not normally exist for walkers A and B separately.

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#476380

Walker-A cannot write v = a + b = 2 + 2 = 4 because walker-A does not have walker-B’s sidewalk speed b = 2, though Professor Longhair does have that.  

However walker-A has collision discomfort equivalent to relative velocity v = 4.  On that basis walker-A can write any of:

v = 4 + 0 = 4

v = 2 + 2 = 4

v = 0 + 4 = 4

It is on this basis that Einstein assigns all of relative velocity 4 to walker-B, i.e. b = 4, while walker-A is “stationary”, a = 0:

v = a + b = 0 + 4 = 4

Einstein’s usual ambiguities creep in.  He has no axis equation of motion:

Not shown: x = v · t

Not shown: x = 4 · t

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#476391

On 6/11/2018 2:58 pm, xip1415926@gmail.com wrote:
> On Monday, November 5, 2018 at 9:16:07 PM UTC-5, Sylvia Else wrote:
> 
>> This is wrong. You are making the unfounded assumption that velocities
>> combine by addition, when they do not. The difference is negligible for
>> small velocities, but large when the magnitudes of the velocities
>> approach the speed of light.
>>
>> Sylvia.
> 
> You are talking about relativistic addition of velocities:
> 
> v = [ a + b ] / [ 1 + ( a · b ) / c² ]
> 
> When a and b are each approximately equal to c you have:
> 
> v = [ c + c ] / 2 = c
> 
> The problem at hand has nothing to do with this.  Problem:  In a junior high school science class, under what circumstances does v exist at all ???  As I pointed out v = a + b exists only for the teacher at the blackboard and does not normally exist for walkers A and B separately.
> 

You've heard of it, but you don't apply it, as is apparent when you try 
to get c + v being the velocity of light send by an observer.

Sylvia.

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#476396

xip1415926@gmail.com wrote:
> On Monday, November 5, 2018 at 9:16:07 PM UTC-5, Sylvia Else wrote:
>> This is wrong. You are making the unfounded assumption that velocities
>>  combine by addition, when they do not. The difference is negligible
>> for small velocities, but large when the magnitudes of the velocities 
>> approach the speed of light.
> 
> You are talking about relativistic addition of velocities:

It should be called “composition of velocities” instead.

> v = [ a + b ] / [ 1 + ( a · b ) / c² ]
> 
> When a and b are each approximately equal to c you have:
> 
> v = [ c + c ] / 2 = c
> 
> The problem at hand has nothing to do with this.  Problem:  In a junior
> high school science class, under what circumstances does v exist at all
> ???

That is a stupid question.  It already follows from the first equation that
v (u) does not only have that one value, but that it depends on the values
of a (v) and b (u').

> As I pointed out v = a + b exists only for the teacher at the blackboard 
> and does not normally exist for walkers A and B separately.

What you pointed out is *incorrect*.

First of all, let us get rid of your ambiguous symbols once and for all.
Physics is an *exact* science.  “a” is already used up for *a*cceleration,
and “b” is not significant of a speed.  You will never arrive at a proper
understanding if you already start with ambiguities.

In physics, we use “v” for speed (from Latin «velōcitās» “speed”), so to
avoid indices, we define

  u := v
  v := a

Also, the speed “b” is actually measured in *another* frame of reference
that is moving at speed v relative to our chosen rest frame.  We call that
frame the “moving” or (less ambiguous) *primed* frame F' (or S' or K',
labels vary), so we define for the speed measured in that frame

  u' := b.

The first equation above has become

  u = (v + u')/(1 + v u'/c²).

u is actually *a function* of v and u', and we write, *exactly*:

  u(v, u') = (v + u')/(1 + v u'/c²).

The second equation is therefore

  u(v = c, u' = c) = (c + c)/(1 + c × c/c²) = 2 c∕2 = c.

Now equipped with proper frames of reference, assume a train passing by you
(towards your right-hand side) at speed v and a person walking in the train
relative to the train (e.g. the chairs at rest on the train) at speed u' in
the same direction).

The speed of the person walking in the train as measured by you, u, is _not_
u = v + u', but u = (v + u')/(1 + v u'/c²).  It is only *approximately*
v + u' as long as v and u' are much smaller than the huge speed of light in
vacuum, c.

The equation v + u' already does not work anymore if u' = c, i.e. there is a
person standing in a train that is passing by you at v that sends a beam of
light along the train, at c (or, more simply, the front lights of a train
passing by you).  You will _not_ measure that light traveling in the
direction of the train at speed v + c > c, but at speed

  u(v, u' = c) = (v + c)/(1 + v c/c²)
               = (v + c)/(1 + v/c²)
               = c (v/c + 1)/(1 + v/c)   eliminating c
               = c (v/c + 1)/(v/c + 1)   commutativity of addition
               = c                       ∀ x ∈ ℝ, x > 0: x/x = 1.

Also, AISB, not only is u = v + u' obviously wrong (look at the first
equation); it and its correction also only works in one dimension,
when velocities v⃗ and u⃗' have the same or opposite direction (and one
is not sideways to the other).  Such as in the examples above (_not_ in the
example of the Sun/solar system moving in the Milky Way and the Milky Way
moving in the Local Group).

HTH.

-- 
PointedEars

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

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#476412

On Tuesday, November 6, 2018 at 3:21:55 AM UTC-5, Thomas 'PointedEars' Lahn wrote:

> Also, AISB, not only is u = v + u' obviously wrong (look at the first
> equation); it and its correction also only works in one dimension,
> when velocities v⃗ and u⃗' have the same or opposite direction (and one
> is not sideways to the other).  Such as in the examples above (_not_ in the
> example of the Sun/solar system moving in the Milky Way and the Milky Way
> moving in the Local Group).
> 
> HTH.
> 

It’s like a game of chess.  You know the rules, you can follow a game’s notation and you can see that Bobby Fischer’s queen sacrifice is really ingenious.  But that’s not our problem.  Why does the game have that one set of rules and not some other?  That’s our problem.

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#476415

On 11/6/18 8:03 AM, xip1415926@gmail.com wrote:
> It’s like a game of chess.  You know the rules, you can follow a 
> game’s notation and you can see that Bobby Fischer’s queen sacrifice 
> is really ingenious.  But that’s not our problem.  Why does the game 
> have that one set of rules and not some other?  That’s our problem.

This is SCIENCE, not chess.

In science, we do not know the "rules" (i.e. the way nature actually
behaves). The best we can do is make models of how nature behaves, test
them experimentally, and refine and improve them.

At present in physics we have two rather complex models which together
apply to just about all interesting physical situations: the standard
model and General Relativity [#]. There are rather strong indications
that neither one of them is a "final theory", but to date all efforts to
improve and/or combine them have failed.

	[#] Some would add the /\CDM model of cosmology.

Note that both of these models have SR at their foundation. SR is among
the best-tested theories we have, right up there with with the atomic
theory of matter, the evolution of life on earth, and the heliocentric
model of the solar system. It is perverse to claim SR is somehow
"wrong", and only grossly ignorant people do so.

Tom Roberts

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#476436

On Tue, 06 Nov 2018 08:41:58 -0600, Tom Roberts wrote:

> At present in physics we have two rather complex models which together
> apply to just about all interesting physical situations: the standard
> model and General Relativity [#]. There are rather strong indications
> that neither one of them is a "final theory", but to date all efforts to
> improve and/or combine them have failed.

First you have to agree with yourself, and everybody else, are those 
models or theories. If for nothing, to avoid confusion.

You build models based on theories, not the other way around. In physics.

> 	[#] Some would add the /\CDM model of cosmology.
> Note that both of these models have SR at their foundation. SR is among
> the best-tested theories we have, right up there with with the atomic
> theory of matter, the evolution of life on earth, and the heliocentric
> model of the solar system. It is perverse to claim SR is somehow
> "wrong", and only grossly ignorant people do so.

SR is just a subset (a misinterpretation) of my Divergent Matter of the 
Moving Bodies Model. (electrodynamically included)

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#476465

On 11/6/18 2:32 PM, Ntowicz Usarczyk wrote:
> On Tue, 06 Nov 2018 08:41:58 -0600, Tom Roberts wrote:
>> At present in physics we have two rather complex models which together
>> apply to just about all interesting physical situations: the standard
>> model and General Relativity [#]. There are rather strong indications
>> that neither one of them is a "final theory", but to date all efforts to
>> improve and/or combine them have failed.
> 
> First you have to agree with yourself, and everybody else, are those
> models or theories. If for nothing, to avoid confusion.

In physics today, "model" and "theory" are synonyms, with the former 
term preferred. That is, we now recognize that what were called 
"theories" in the past were really models of how nature behaved. The key 
concept is that models necessarily have a domain of applicability -- 
theories do, too, but it is not so ingrained in the word.

> You build models based on theories, not the other way around. In physics.

Nope. See above. The meanings of these words have MORPHED.

> [... further repetitions of nonsense]

Tom Roberts

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#476515

On Tue, 06 Nov 2018 20:39:15 -0600, Tom Roberts wrote:

> On 11/6/18 2:32 PM, Ntowicz Usarczyk wrote:
>> On Tue, 06 Nov 2018 08:41:58 -0600, Tom Roberts wrote:
>>> At present in physics we have two rather complex models which together
>>> apply to just about all interesting physical situations: the standard
>>> model and General Relativity [#]. There are rather strong indications
>>> that neither one of them is a "final theory", but to date all efforts
>>> to improve and/or combine them have failed.
>> 
>> First you have to agree with yourself, and everybody else, are those
>> models or theories. If for nothing, to avoid confusion.
> 
> In physics today, "model" and "theory" are synonyms, with the former
> term preferred. That is, we now recognize that what were called
> "theories" in the past were really models of how nature behaved. The key
> concept is that models necessarily have a domain of applicability --
> theories do, too, but it is not so ingrained in the word.

Totally nonsense, and you are refusing to learn. Distinct terminologies 
applies to distinct things. You are actually give a reason for why those 
are distinct.

>> You build models based on theories, not the other way around. In
>> physics.

> Nope. See above. The meanings of these words have MORPHED.

You are actually said the same in other words. Can't you see it, give me a 
break.

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#476447

xip1415926@gmail.com wrote:
> On Tuesday, November 6, 2018 at 3:21:55 AM UTC-5, Thomas 'PointedEars'
> Lahn wrote:
>> Also, AISB, not only is u = v + u' obviously wrong (look at the first 
>> equation); it and its correction also only works in one dimension, when
>> velocities v⃗ and u⃗' have the same or opposite direction (and one is
>> not sideways to the other).  Such as in the examples above (_not_ in
>> the example of the Sun/solar system moving in the Milky Way and the
>> Milky Way moving in the Local Group).
>> 
>> HTH.
> 
> It’s like a game of chess.  You know the rules, you can follow a game’s
> notation and you can see that Bobby Fischer’s queen sacrifice is really
> ingenious.  But that’s not our problem.  Why does the game have that one
> set of rules and not some other?  That’s our problem.

You do realize that such unrelated, incoherent rambling
is a clear sign of a mental illness on your part, yes?

-- 
PointedEars

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

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