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Re: What is mass?

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  Re: What is mass? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-26 08:35 +0200
    Re: What is mass? Fabian Russell <root@localhost.localdomain> - 2015-09-26 12:23 +0000
      Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 09:07 -0400
        Re: What is mass? Fabian Russell <root@localhost.localdomain> - 2015-09-26 18:18 +0000
          Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 14:45 -0400
            Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-26 19:49 +0000
              Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 16:38 -0400
                Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-26 21:35 +0000
                  Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 18:44 -0400
                    Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-26 22:57 +0000
                      Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 19:06 -0400
                        Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-26 23:18 +0000
                          Re: What is mass? pnalsing@gmail.com - 2015-09-26 16:23 -0700
                            Re: What is mass? pnalsing@gmail.com - 2015-09-26 16:42 -0700
                              Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-27 00:21 +0000
                              Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 21:24 -0400
                              Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 21:32 -0400
                              Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-27 01:20 -0400
                          Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 19:42 -0400
                            Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-27 00:22 +0000
                              Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 21:29 -0400
                                Re: What is mass? Kent Beeler <kenbee@jefffast.au> - 2015-09-27 10:33 +0000
          Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 14:57 -0400
    Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 13:09 -0400
      Re: What is mass? Jimmie Wynne <jimmwyn@metermap.org> - 2015-09-26 17:25 +0000
        Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 14:40 -0400
      Re: What is mass? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-26 21:42 +0200
        Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-26 16:35 -0400
          Re: What is mass? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-27 13:48 +0200
            Re: What is mass? kefischer <emoneyjoe@iglou.com> - 2015-09-27 11:59 -0400

Page 2 of 2 — ← Prev page 1 [2]

#365391

On Sun, 27 Sep 2015 00:22:47 +0000 (UTC), Kent Beeler
<kenbee@jefffast.au> wrote:

>kefischer wrote:
>
>> On Sat, 26 Sep 2015 23:18:17 +0000 (UTC), Kent Beeler
>> <kenbee@jefffast.au> wrote:
>> 
>>>kefischer wrote:
>>>
>>>>>This to morons must feel like a mystery. To the experienced those
>>>>>things falls to defaults, aka at t = 0. Use your brain and fill in the
>>>>>blanks. Ie take the air resistance /friction as zero, zero initial
>>>>>speed etc.
>>>>>
>>>>>You aint look like much experienced in Divergent Matter. Merely like a
>>>>>piano player.
>>>> 
>>>> Your memory is bad, can't you remember across name changes?
>>>
>>>That must be my other brother Darryl. Nice to meet you.
>>>
>>>> It was piano mover. Who knows gravity better than a piano mover?
>>>
>>>There is no Gravity in Divergent Matter, it must be something you
>>>misunderstand. Then come up with that number, the time it takes for each
>>>stone to fall. Piece of cake in Divergent Matter.
>> 
>>         You are a stupid name changing troll, what do you know?
>> They don't fall in Divergent Matter, and I don't think they fall in GR.
>> The surface will hit both at the same time, so all you ask is to solve a
>> simple acceleration problem, the time for the surface to accelerate
>> upward the specified distance.
>
>Then come up with the derivation end evaluate the number, fool. You are 
>not even a piano mover I suspect. It takes much more brain to become a 
>piano mover.

         Ask a fifth grader.

         If you have the silly idea that the surfaces of the rocks
should be used in the problem, forget it, the center of mass of
the rocks is what should be used in the problem.

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#365425

kefischer wrote:

>>Then come up with the derivation end evaluate the number, fool. You are
>>not even a piano mover I suspect. It takes much more brain to become a
>>piano mover.
> 
>          Ask a fifth grader.

Such that must be above your level since you ask me to do that.

>          If you have the silly idea that the surfaces of the rocks
> should be used in the problem, forget it, the center of mass of the
> rocks is what should be used in the problem.

Does not matter, you furniture mover, the one of the stone must be larger 
than the other stone, assuming same structure to the both. 

You are impotent in Divergent Matter, and your denial just serves as an 
another proof. I dont want to hear anything about Divergent Matter coming 
from you. Just shut up, or talk about pianos, something your should be 
good at.

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#365353

On 26 Sep 2015 18:18:00 GMT, Fabian Russell <root@localhost.localdomain>
wrote:

>On Sat, 26 Sep 2015 09:07:48 -0400, kefischer wrote:
>
>>
>> but the basic premise of trying to confirm the
>> equality of gravitational mass and inertial mass
>> is an anti-Einstein exercise, and a support of
>> Newtonian concepts.
>> 
>
>But the tests go on.  Most, I would believe, consider a test of the
>PoE as a test of GR:
>
>https://www.cfa.harvard.edu/pag/index_files/Page1098.htm

        Ah, nuts, I didn't look at that link until after I replied,
now I see that I disagree with all four conclusions itemized
at the end.

       I also think the use of terms like the WEP and the
idea that any of these tests have anything to do with
a gravitational "field" is also Newtonian nonsense,
everybody in the period 1907 to 1915 was still
thinking gravitation was a "field", including Einstein.

       But I think that now, to really appreciate GR,
and understand it's basic premise, the idea of
any real "field" entity is a hold over from Newton.

      Motion in free space is pure relative motion,
inertial motion with the presence of matter
altering the geometry, but that geometry,
and space-time NOT being the cause of
anything except measurement and human
observations.

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#365338

On Sat, 26 Sep 2015 08:35:23 +0200, Thomas 'PointedEars' Lahn
<PointedEars@web.de> wrote:

>[X-Post sci.physics, sci.physics.relativity;
> F'up2  <news:sci.physics.relativity>]
>
>Fabian Russell wrote:
>
>> On Wed, 23 Sep 2015 19:12:18 +0200, Poutnik wrote:
>>> cannot be completely wrong equation.
>> 
>> The equation is wrong because it specifies mass, m, as *the* mass,
>> i.e. the definitive mass or the one-and-only mass.
>
>There is only mass.  To answer the question in the Subject header field 
>value: Mass is a measure of the energy content of a body at rest in the 
>laboratory frame (of reference): E = v(pc)² + (mc²)²) ? m = E/c² for p = 0, 
>with p = ?mv (relative rest ? ? = 1, v = 0).
>
>That is why we build huge machines to *accelerate* subatomar particles close 
>to the speed of light in vacuum, and have them collide with each other to 
>create particles with a lot of mass and, more recently, to "produce" energy 
>through nuclear fusion.
> 
>> Correctly written, the *inertial* mass must be indicated because,
>> as already stated, there are two different "kinds" of mass.
>
>Two terms for the same thing is not how science works.
> 
>> For some reason, the concepts of inertial mass and gravitational
>> mass have been effectively purged from physics,
>
>Because physics is a science.  Superfluous terms are not used in science.  
>One uses different terms for different things, the same term for the same 
>thing.
>
>> but they are still valid.
>
>Because you say so?
>
>> GR *assumes* the equivalence of both types
>
>Because it can be *demonstrated*.  Read on the elevator experiment: Without 
>additional information, you cannot tell whether you are far away from a 
>source of gravity or in free fall, and you cannot tell whether you are 
>accelerating or near a source of gravity.

       Big error there, either you are accelerating,
like in a rocket ship, or you are on the surface
of a gravitating body like Earth.

       All motion in free space is inertial motion
with no acceleration felt.


>(Einstein is often described as a theoretical genius only.  But, in fact, 
>the text of his works shows that he was deeply guided by experiment.  And 
>there is other evidence: He co-designed and had built an observatory [the 
>Einsteinturm in Potsdam, Germany] only for testing GR.  And he would have 
>thrown out GR like yesterday’s newspaper if it had given the wrong result 
>for the precession of the perihelion of Mercury.  Just as he wrote [in 
>German] “then away with the cosmological term” regarding his field equations 
>when Hubble’s observations confirmed Lemaître’s theory that the universe was 
>in fact not static, but expanding.)
>
>> and perhaps for this reason all textbooks incorrectly mention only a 
>> single type of mass.  But, as also mentioned, GR is not yet universally
>> established.
>
>In crackpot’s heads, perhaps.  Everywhere else it is, quite literally, 
>“universally” established, for example:
>
>- in timekeeping (precise clocks are gauged based on their elevation; it can
>  be demonstrated that those at higher elevation tick faster than their
>  same-model counterparts at lower elevation)
>
>- in communication (with orbital spacecraft and interplanetary probes);
>
>  * as a special case, in satellite navigation (GPS and alternatives)
>
>  (again, clocks close to a massive body tick slower than those farther away
>  from it)
>
>- in astronomy and astrophysics (perihelion precession, gravitational
>  lensing, black holes)
>
>- in cosmology (the ?CDM, or *standard* model of cosmology)
>
>
>PointedEars

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#365342

kefischer wrote:

>        All motion in free space is inertial motion
> with no acceleration felt.

Acceleration is not something to be felt, tenacious poor idiot.

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#365348

On Sat, 26 Sep 2015 17:25:12 +0000 (UTC), Jimmie Wynne
<jimmwyn@metermap.org> wrote:

>kefischer wrote:
>
>>        All motion in free space is inertial motion
>> with no acceleration felt.
>
>Acceleration is not something to be felt, tenacious poor idiot.

        Change your name, and get one with a brain, troll.

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#365356

kefischer wrote:

> […] Thomas 'PointedEars' Lahn […] wrote:
>>> GR *assumes* the equivalence of both types
>>
>> Because it can be *demonstrated*.  Read on the elevator experiment:
>> Without additional information, you cannot tell whether you are far away
>> from a source of gravity or in free fall, and you cannot tell whether you
>> are accelerating or near a source of gravity.
> 
>        Big error there, either you are accelerating,
> like in a rocket ship, or you are on the surface
> of a gravitating body like Earth.

The error is yours.

You can also be accelerated on the surface of a gravitating body like Earth.  
For example, when you push the throttle pedal or the brake pedal of an 
automobile with a running motor (and no other brakes engaged) your motion is 
accelerated relative to the surface: in a fixed time interval you move 
either more or less distance than in the interval before; the *magnitude* of 
your velocity changes.

And if you are turning with the car, the car is accelerated towards the 
centroid of the corresponding curve (which causes you to be seemingly pushed 
away from it) even if your (non-zero) speed remained constant; the 
*direction* of the car’s velocity changes (and you, otherwise in inertial 
motion, are forced to comply, not being in inertial motion anymore then).

In fact, your motion is accelerated in the frame of reference of an extra-
terrestrial observer even if you stand still on the surface of the Earth, 
because the Earth is rotating about its axis *and* revolving around the Sun.

Velocity is the change of position in a certain time interval:

  v⃗ = dr⃗∕dt

Acceleration is the change of velocity in a certain time interval:

  a⃗ = dv⃗∕dt = d²r⃗∕dt²
 
>        All motion in free space is inertial motion
> with no acceleration felt.

Wrong.  If you hit the thrusters of a rocketship, you are accelerating (your 
velocity changes); ask astronauts whether they feel that.  And ask yourself 
why they are training in large centrifuges.


PointedEars
-- 
I heard that entropy isn't what it used to be.

(from: WolframAlpha)

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#365366

On Sat, 26 Sep 2015 21:42 +0200, Thomas 'PointedEars' Lahn
<PointedEars@web.de> wrote:

>kefischer wrote:
>
>> […] Thomas 'PointedEars' Lahn […] wrote:
>>>> GR *assumes* the equivalence of both types
>>>
>>> Because it can be *demonstrated*.  Read on the elevator experiment:
>>> Without additional information, you cannot tell whether you are far away
>>> from a source of gravity or in free fall, and you cannot tell whether you
>>> are accelerating or near a source of gravity.
>> 
>>        Big error there, either you are accelerating,
>> like in a rocket ship, or you are on the surface
>> of a gravitating body like Earth.
>
>The error is yours.

       Not at all, you are adding qualifiers to my
casual statements that I did not intend and
did not mean to infer.


>You can also be accelerated on the surface of a gravitating body like Earth.  
>For example, when you push the throttle pedal or the brake pedal of an 
>automobile with a running motor (and no other brakes engaged) your motion is 
>accelerated relative to the surface: in a fixed time interval you move 
>either more or less distance than in the interval before; the *magnitude* of 
>your velocity changes.

       That's the same as rocket thrust, but your ending statement
is false, there is NO acceleration motion or change in position
until there is a non-zero velocity.

       A change in velocity is acceleration and accelerated motion.


>And if you are turning with the car, the car is accelerated towards the 
>centroid of the corresponding curve (which causes you to be seemingly pushed 
>away from it) even if your (non-zero) speed remained constant; the 
>*direction* of the car’s velocity changes (and you, otherwise in inertial 
>motion, are forced to comply, not being in inertial motion anymore then).

       Why are you reciting things I learned in the 1930s?


>In fact, your motion is accelerated in the frame of reference of an extra-
>terrestrial observer even if you stand still on the surface of the Earth, 
>because the Earth is rotating about its axis *and* revolving around the Sun.

        Good physics does not include observation from
a distance or coordinate motion.


>Velocity is the change of position in a certain time interval:
>
>  v? = dr?/dt
>
>Acceleration is the change of velocity in a certain time interval:
>
>  a? = dv?/dt = d²r?/dt²

         Ok, but without some aspect of velocity, 
there is no relative motion.

 
>>        All motion in free space is inertial motion
>> with no acceleration felt.
>
>Wrong.  If you hit the thrusters of a rocketship, you are accelerating (your 
>velocity changes); ask astronauts whether they feel that.  And ask yourself 
>why they are training in large centrifuges.
>
>
>PointedEars

        I felt it in the 1930s on a school yard merry-go-round,
and in the early 1940s on an amusement park ride.

        There is no way that I can KNOW what Einstein
intended in GR, and he may have been too embroiled
in relativity theory to be completely rational about
apparent motion due to gravity.
       But I think the elevator in space pulled by a rope
is evidence enough that he intended for "free" motion
in space to be inertial motion, and the correct view
of GR still hinges on that premise.

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#365432

kefischer wrote:

> […] Thomas 'PointedEars' Lahn […] wrote:
>> kefischer wrote:
>>>        Big error there, either you are accelerating,
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>> like in a rocket ship, or you are on the surface
                           ^^^^^^^^^^^^^^^^^^^^^^^^^
>>> of a gravitating body like Earth.
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>> The error is yours.
>
>        Not at all, you are adding qualifiers to my
> casual statements that I did not intend and
> did not mean to infer.

You have claimed *exclusiveness* of acceleration and gravitation (“either …
or”), but exclusiveness is not the case (in fact, the many confirmations of
the equivalence principle show that both are indeed the same thing).

You were/are wrong, and now you are denying that.

>>You can also be accelerated on the surface of a gravitating body like
>>Earth. For example, when you push the throttle pedal or the brake pedal of
>>an automobile with a running motor (and no other brakes engaged) your
>>motion is accelerated relative to the surface: in a fixed time interval
>>you move either more or less distance than in the interval before; the
>>*magnitude* of your velocity changes.
>
>        That's the same as rocket thrust,

And it happens *while on the surface of Earth*, under *gravity*, which
disproves your claim that one could only have *either* gravity *or*
acceleration.

>        but your ending statement is false,

No, it is not.

> there is NO acceleration motion or change in position until there is a
> non-zero velocity.

No, for example your free fall towards the center of mass of Earth is
prevented by forces exerted by the surface of the Earth (specifically,
electrostatic repulsion).  And that is _not_ caused by the surface moving
with respect to the center of mass or you, different to what you are
claiming in this “Divergent Matter” fantasy of yours.

>        A change in velocity is acceleration and accelerated motion.

Yes.  But this is a /non sequitur/ regarding your previous statement.
Forces cause the change of velocity of a test body, and we call that
acceleration.  In the case of Earth’s gravity, electrostatic forces
make you stop, prevent you from further falling freely.

This is *independent* from whether you think of gravity as an attracting
force that pulls you towards the center of mass, or argue based on GR where
your motion is one along a geodesic trajectory in a spacetime that is curved
in the presence of the mass–energy–momentum of Earth.

>        Why are you reciting things I learned in the 1930s?

Because you appear to have forgotten all of it.

>>In fact, your motion is accelerated in the frame of reference of an extra-
>>terrestrial observer even if you stand still on the surface of the Earth,
>>because the Earth is rotating about its axis *and* revolving around the
>>Sun.
>
>         Good physics does not include observation from
> a distance or coordinate motion.

Utter nonsense.  You have not the slightest idea what good physics could be.

>>>        All motion in free space is inertial motion
>>> with no acceleration felt.
>>Wrong.  If you hit the thrusters of a rocketship, you are accelerating
>>(your velocity changes); ask astronauts whether they feel that.  And ask
>>yourself why they are training in large centrifuges.
>
>         I felt it in the 1930s on a school yard merry-go-round,
> and in the early 1940s on an amusement park ride.

Good.  Now *think* about what happens then.

>         There is no way that I can KNOW what Einstein
> intended in GR,

That is true insofar as you are continuing to *refuse to study his works*,
where he makes that clear.

> and he may have been too embroiled in relativity theory to be completely
> rational about apparent motion due to gravity.

Sure, not you are the crackpot, Einstein is.  What are you dreaming of at
night?

>        But I think the elevator in space pulled by a rope
> is evidence enough that he intended for "free" motion
> in space to be inertial motion, […]

Think again.


PointedEars
-- 
A neutron walks into a bar and inquires how much a drink costs.
The bartender replies, "For you? No charge."

(from: WolframAlpha)

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#365457

On Sun, 27 Sep 2015 13:48:32 +0200, Thomas 'PointedEars' Lahn
<PointedEars@web.de> wrote:

>kefischer wrote:
>
>> […] Thomas 'PointedEars' Lahn […] wrote:
>>> kefischer wrote:
>>>>        Big error there, either you are accelerating,
>                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>> like in a rocket ship, or you are on the surface
>                           ^^^^^^^^^^^^^^^^^^^^^^^^^
>>>> of a gravitating body like Earth.
>    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>> The error is yours.
>>
>>        Not at all, you are adding qualifiers to my
>> casual statements that I did not intend and
>> did not mean to infer.
>
>You have claimed *exclusiveness* of acceleration and gravitation (“either …
>or”), 

        No, I haven't, the discussion is obviously
about gravity, not ordinary mechanics.


>but exclusiveness is not the case (in fact, the many confirmations of
>the equivalence principle show that both are indeed the same thing).

        Apparently you are using a blurred definition
of the equivalence principle.

        According to English translations, when Einstein
used the term "equivalence principle", it was the
equivalence of gravitational mass and inertial mass
that  he was talking about, not acceleration and
gravity.

       If he was talking about _HIS_ Principle of
Equivalence, he meant the elevator in space
pulled by a rope, accelerating upward.

       This is clear in the English translations
of his words and papers, because he said
gravity is like acceleration, and the absence
of gravity is like inertial motion.


        All of the added break down elaboration
of the various names and flavors (ep, eep,
wep, sep, etc.) are just egotistical nonsense
bringing Newtonian concepts back into 
gravity theory.


>You were/are wrong, and now you are denying that.

       No, I was talking about gravity, not elementary
Newtonian mechanics that I assume everybody
knows.


>>>You can also be accelerated on the surface of a gravitating body like
>>>Earth. For example, when you push the throttle pedal or the brake pedal of
>>>an automobile with a running motor (and no other brakes engaged) your
>>>motion is accelerated relative to the surface: in a fixed time interval
>>>you move either more or less distance than in the interval before; the
>>>*magnitude* of your velocity changes.
>>
>>        That's the same as rocket thrust,
>
>And it happens *while on the surface of Earth*, under *gravity*, which
>disproves your claim that one could only have *either* gravity *or*
>acceleration.

        It happens any place where there is a force applied,
all thinking about gravity is about falling objects near
massive bodies.
       I did NOT say "one could only have "either"",
but you snipped what I said.

       That is a deplorable tactic used by bodkin
and Gary when they are trying to win an argument
instead of sticking to the surface.
       This detracts and diverts from the discussion
which is about the thinking and philosophy of
thought experiments about gravity and freefall.


>>        but your ending statement is false,
>
>No, it is not.

     Claiming motion of translation without any
velocity at all is a false claim, that way of thinking
is what causes many people to think that any
acceleration can occur without some residual
velocity or change of velocity, acceleration
is not motion, it is rate of change of rate of
motion.


>> there is NO acceleration motion or change in position until there is a
>> non-zero velocity.
>
>No, for example your free fall towards the center of mass of Earth is
>prevented by forces exerted by the surface of the Earth (specifically,
>electrostatic repulsion).  And that is _not_ caused by the surface moving
>with respect to the center of mass or you, different to what you are
>claiming in this “Divergent Matter” fantasy of yours.

       A fantasy is no different than a factual theory,
the physics can be good, that is what makes
good science fiction, as different than monster
fiction.

        To be frank, I think claiming there is proper
acceleration of the surface _without_ upward
motion is loony talk.   
        Just as claiming freefall is not falling, but
"at rest" or inertial motion is loony unless the
surface is moving upward.

        There are lots of websites and lectures
that spend a lot of time reciting all the reasons
the surface does not and cannot be moving
upward, and they all fail.


>>        A change in velocity is acceleration and accelerated motion.
>
>Yes.  But this is a /non sequitur/ regarding your previous statement.

        It can't be, unless you accept that if freefall
is inertial motion as Einstein's PoE assumes.


>Forces cause the change of velocity of a test body, 

        Oh, no, surely we are not back to grade school
Newtonian concepts.

        The very essence of General Relativity gravity
considerations is force free apparent change in
motion, requiring the use of the term "proper
acceleration" to be applied for cases of "real"
acceleration caused by a force.

      There is no need for the term "proper"
if you revert back to Newtonian nonsense.


>and we call that
>acceleration.  In the case of Earth’s gravity, electrostatic forces
>make you stop, prevent you from further falling freely.

       Sure, that doesn't make any sense at all
except to bring Newton back to life proclaiming
Einstein was wrong, and the Newtonian freefall 
concept of accelerated motion was correct
all along.


>This is *independent* from whether you think of gravity as an attracting
>force that pulls you towards the center of mass, or argue based on GR where
>your motion is one along a geodesic trajectory in a spacetime that is curved
>in the presence of the mass–energy–momentum of Earth.

       Hardly, there has to be agreement of the 
concepts of inertial motion freefall vs force
induced downward acceleration freefall.

        The basic premise of equal falling
in the General Theory of Relativity _IS_
that the observed falling objects are NOT
falling.

       To be lucid and sane, the surface has
to be accelerating upward in that premise,
and there has to be a residual velocity of
the surface upward, any continuous upward
acceleration has to result in a substantial
upward velocity.

      [In this particular case] that velocity
has limiting parameters, the total distance
of the motion of translation in terms of
practical consideration, can not exceed
the radius of the Earth.

>>        Why are you reciting things I learned in the 1930s?
>
>Because you appear to have forgotten all of it.

        No, I just don't want to waste your time
reciting all possible examples of proper
acceleration, and having to qualify that
the considerations are about motion due
to gravity and not any force assumptions
by minds contaminated by Newtonian
concepts.


>>>In fact, your motion is accelerated in the frame of reference of an extra-
>>>terrestrial observer even if you stand still on the surface of the Earth,
>>>because the Earth is rotating about its axis *and* revolving around the
>>>Sun.
>>
>>         Good physics does not include observation from
>> a distance or coordinate motion.
>
>Utter nonsense.  You have not the slightest idea what good physics could be.

       It must separate coordinate motion from
proper motion, which is what Einstein established
with General Relativity, in order to define motion
rationally, instead of continuing the concepts of
imaginary forces that don't exist.


>>>>        All motion in free space is inertial motion
>>>> with no acceleration felt.
>>>Wrong.  If you hit the thrusters of a rocketship, you are accelerating
>>>(your velocity changes); ask astronauts whether they feel that.  And ask
>>>yourself why they are training in large centrifuges.
>>
>>         I felt it in the 1930s on a school yard merry-go-round,
>> and in the early 1940s on an amusement park ride.
>
>Good.  Now *think* about what happens then.

       That is explained in any good discussion of
centripetal/centrifugal motion.

       But since this is about gravity and the concepts
used in General Relativity, the "force" I felt is
_exactly_ like what I feel right now, except
the vector relative to the direction of the center
of mass of the Earth was different.


>>         There is no way that I can KNOW what Einstein
>> intended in GR,
>
>That is true insofar as you are continuing to *refuse to study his works*,
>where he makes that clear.
   
        He attempted to make clear that real acceleration
should be designated "proper acceleration, and any
other observed acceleration is "coordinate" acceleration.

       That is the only possible way to have inertial
motion freefall, and for gravity to be like acceleration.
       He probably did not expect the human mind
that learned Newtonian concepts to forever mix
up Newtonian concepts along with GR concepts.


>> and he may have been too embroiled in relativity theory to be completely
>> rational about apparent motion due to gravity.
>
>Sure, not you are the crackpot, Einstein is.  

        I did not say that, and I have never thought that,
in fact, while I never hear voices, I think that if
Einstein was whispering in my ear, he would
be saying what I am saying.

>What are you dreaming of at night?

        I usually forget shortly after awakening.


>>        But I think the elevator in space pulled by a rope
>> is evidence enough that he intended for "free" motion
>> in space to be inertial motion, […]
>
>Think again.
>
>PointedEars

         I don't have to imagine that, it is in his word,
written in many places.

         If a person is not able to separate Newtonian
concepts from GR concepts, they are not able to
think rationally.

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