Re: THE GENERAL RELATIVITY.

Mike wrote:
Paul B. Andersen wrote:
Mike wrote:
Paul B. Andersen wrote:
Sorcerer wrote:
"Paul B. Andersen" <paul.b.andersen@xxxxxx> wrote in message
news:1160036583.644820.188590@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
| Stamenin skrev:
| > THE EQUALITY OF INERTIAL AND GRAVITATIONAL MASS AS
| > AN ARGUMENT FOR THE GENERAL POSTULATE OF RELATIVITY.
| >
| > At the page 68 of his book Relativity Einstein writes about the General
| > postulate of relativity. He imagines a large portion of empty space, so
| > far removed from the stars, that we have before us approximately the
| > conditions required by the fundamental law of Galilei. It is then
| > possible to choose a Galileian reference body for this part of space
| > relative to which points at rest remain at rest and points at motion
| > continue permanently in uniform rectilinear motion.
| > From this supposition is visible that Einstein uses the name
| > Galileian system only to not make use of the Newton's absolute
| > coordinate system, because between them in this portion of space they
| > are both of them valid and both are impossible to be determined.
| > And by there definitions they represent the same thing, a coordinate
| > system that is staying in a large portion of the cosmos where do not
| > exist gravitational forces.
| > In continuation he says: In this large space he puts a chest and a man
| > in it. To the lid of the chest is fixed a hook with a rope and by an
| > imaginary being is pulled "upwards". But how does the man in the
| > chest regard the process, asks Einstein.
| > The acceleration at the chest will be transmitted to him by the
| > reaction of the floor of the chest. This situation is complete similar
| > with the situation in a room at the earth and that there is a
| > gravitational field.
| > To the end of the page 69 Einstein says: "Ought we to smile at the
| > man and say that he errs in his conclusion? I do not believe we ought
| > to if we wish to remain consistent, we must rather admit that his mode
| > of grasping the situation violates neither reason nor known mechanical
| > laws. Even though it is being accelerated with respect to the
| > "Galileian space" first considered, we can nevertheless regard the
| > chest as being at rest. We have thus good grounds for extending the
| > principle of the relativity to include bodies of reference which are
| > accelerated with respect to each other, and as a result we have gained
| > a powerful argument for a generalized postulate of relativity".
| > So we can see that Einstein by using the behavior of the inertial and
| > the gravitational forces to acct upon every atom of the material body
| > reached the conclusion that an accelerated coordinate system is an
| > absolute inertial system.
| > Evidently this conclusion is in contradiction:
| > 1) With the starting supposition that the chest is in an accelerated
| > motion.
| > 2) With the principle of the relativity that says that is not valid for
| > the accelerated systems of coordinates because it is valid only for
| > systems of coordinates that are in right line motion and with a
| > constant speed.
| > 3) By this he makes confusion between the gravitational and inertial
| > forces considering them as being of the same nature. But we know that
| > that they are different, the gravitational force is an external force
| > of the body and inertial force is an internal force in the body. The
| > only thing that is common to these forces is the behavior to act upon
| > every atom of the material body.
| > 4) And by this he concludes that has gained a powerful argument for the
| > generalization of this principle of the relativity!!!!
| > This kind of logic could be named, the negation of the affirmation.
| > And after that Einstein continues: " We must note carefully that the
| > possibility of this mode of interpretation rests on the fundamental
| > property of the gravitational field of giving all bodies the same
| > acceleration, or, what comes to the same thing, on the law of the
| > equality of inertial and gravitational mass"!!!
| > This final argumentation shows how difficult was for Einstein trying
| > in such a way to trick the reader by using such an illogical
| > argumentation.
| > What I can conclude after all that is said, is the fact that the
| > General theory of the relativity has a tricky base and not powerful
| > arguments and fundamental laws of the nature.
| > 2/10/2006.
|
| Einstein's book "Relativity" is a popular book, not a scientific
| paper.

Yes, science fiction.


| It can at the very best give you a vague idea of what GR is about.

Bul***, it tells you exactly.


| Believing that you after having read a popular book are competent
| to critisize the theory described in that book is a rather naive idea.
|
Learn to spell "critic" then go on from there, critic.


| And you failed to grasp the basic idea which Einstein tried to mediate.
| You say: " the gravitational force is an external force of the body"
| Is it?

Yes.


| If it is an external force, why can't you feel it?

If there are radio waves, why can't you see them?


| The only external force you now can feel is the force
| from your chair, pushing you upwards.
| If you jump out the window, you feel nothing.
| That is because no external forces are acting on you while
| you are in free fall.

Hahahaha!

The moron Andersen still doesn't understand Newton's third law.
You'll be saying next that he doesn't accelerate!

Hilarious!

One question, Androcles.

If you put yourself behind the wheel in a F1 car,
you can accelerate at 1g in the horizontal direction.
The will feel the 1000N force pushing your 100 kg body
in the back extremely well.
You feel your reaction to the force exterted on you by the chair that
is essentially taking you forward. This is an inertial force. No chair,
no motion. make sure it is bolted well.

If you jump out of the window, you feel nothing
pushing you while you are falling.
Assuming negligible air friction, you feel nothing because there is no
chair as in the car case. There is no connection between the two
examples because you are trying to make Force a directly observable
quantity, which IS NOT and Einstein failed to understand this and
ridiculed himself although by accident the EP is valid locally.

If the acceleration is the same in the two cases,
why is then what you feel so very different?
You know, there are deaf, blind, autistic and all sorts of people. Are
you going to base a science on what you feel?
So we better use instruments.
What does an accelerometer measure if you put it in the F1 car?
In your chair?
While free falling?

Then, you should understand that Force is not any directly measurable
quantity but it is only measured through its effect, acceleration in
the case of inertial forces and displacement in the case of potential
forces. When the second derivative of position wrt time is not zero we
know there is a force acting on a body. Nobody cares what you feel.

Thought experiments are the curse of modern science. You are wasting
your time dealing with issues you do not understand.
Do you think an accelerometer in a real experiment
would show a different acceleration than I stated
in my thought experiments above?

You are wondering because you do not understand very basic physics and
at the same time you have been brain washed by icreadible
misconceptions and lies.

An accelerometer can measure only "by reacting" to a force. A explained
to you this already. Your body acts like an accelerometer when
contrained by a chair. Since action-reactions pairs act on different
bodies that act on each other, you need to contrain the accelerometr on
free fall to get the reading. That is not possible of course and you
get no reading. The same would happen if you let an accelerometr loose
in the F1 car.

An accelerometer measures proper acceleration.
This is the _only_ acceleration that is measurable
without external references.
Doesn't that tell you something?

Put the accelerometer on your chair, and it shows 1g acceleration.
Put the accelerometer in the F1 car, it shows 1g horizontal
acceleration and 1g vertical acceleration, that is 1.41g.
Throw it out the window, and it shows zero acceleration
while in free fall.

Now, having reviewd basic physics, you can make an accelerometer using
a laser and measure position to a reference point. If you differentiate
twice carefully you get acceleration. Digital encoders attached on
motir shafts are used for this purpose all the time. You get a measure
of acceleration and then multiply by mass to get the force.

Never before saw I anybody calling an instrument which measures
angular velocity an accelerometer. :-)

The accelerometers that are used all the time measure
proper acceleration.

Remember, Force is not a directly measurable quantity but we measure
only its affects.

Sure. There are indeed very few entities which can be measured directly.
But the external force acting on a mass is easily measured, although
indirectly.

Are you going to tell me that force is unmeasurable? :-)

If you are clever enough and open minded you will understand the flaws
of the Einstein thought experiment and also way although he was totally
wrong and had misconceptions about basic physics it turns out the EP is
valid locally.

Open minded? :-)
You do not understand GR, do you?

Both GR and Newtonian gravitation are consistent theories.
If they predicted the same for everything, they would be two alternative
interpretations of the same reality. In that case it would be a matter
of taste if you preferred to interpret gravitation as a force according
to Newton, or as a curvature of space-time according to GR.
But they don't predict the same for everything.
And in every case where there is a measurable difference between
the predictions of Newtonian gravitation and GR, GR has come out on top.

Newtonian gravitation is falsified.
GR is not - so far.
If it ever is, Newtonian gravitation is not an alternative.

A question:
If you are orbiting the Moon, what is your acceleration?
How would you measure it?

Paul
.

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