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Re: What is mass?

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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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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

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