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Question on Gravitational Force

# Question on Gravitational Force

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nakayama

Yokohama, Japan

#1 Jan 3, 2011
To what precision, are we able to know the direction that gravitational force acts (for example, the sun's)? Possibly, it may exceed light speed ? Therefore it's untouched ?
nakayama

Yokohama, Japan

#2 Jan 4, 2011
About my question, allow me to expound a little..... Apparent position of the sun is fixed on the celestial sphere (it's a phenomenon, "Light-Time Correction"). So, apparent position is the position that the sun was 8 minutes odd before. Therefore if gravitational force comes at infinite speed, "emitted position" is different. The difference is a 2 degree odd angle (Maximum).

[P.S.] "Light-Time Correction" is a phenomenon based on the rest frame. So common explanation is complicated.
[P.S.] It's supposed that we can know the coming direction of gravitational force sufficiently. And it is not affected by the motion of the sun and the earth.
nakayama

Yokohama, Japan

#3 Jan 10, 2011
Very Sorry, i made a silly error (above post is wrong, i can't erase). Allow me to correct by the following.

There is a space ship. It is at a standstill in the aether. Therefore every aberration (including secular aberration) doesn't occur on the loaded telescope. The sun (distance from the space ship is 1.5 hundred million km) is passing at the speed of 400 km/sec. Because of "Light-Time Correction", apparent position of the sun is the position that the sun was 8 minutes odd before. Therefore if gravitational force comes at infinite speed, "emitted position" is different. But this difference is slight. Below a 0.1 degree angle (Maximum). Can we distinguish it ?

[P.S.] From the earth, the same measurement will be possible logically. Because the motion of the earth relative to the aether is measurable.
nakayama

Yokohama, Japan

#4 Jan 10, 2011
In "Encyclopaedia Britannica" 1969, there is a passage as follows (in item "Gravitation" ; original text). "If the action of gravitation were not absolutely instantaneous"(omission) "All experiments and observations were, however, consistent with the law, from the short distances employed in laboratory experiments to the long ranges used in interplanetary calculations". It says, action is instantaneous. What !? What about that light cone !?

If the speed of gravity (gravitational force) is not infinite (the same as light speed), orbit of a planet seems to be affected characteristically by the sun's gravity. The sun is moving in an uniform linear motion. This line is supposed to cross the orbit (supposed to be true circle) at two point, A and B (like Greek letter &#966; phi). If the speed of gravity is independent of the motion of the sun (supposed to follow the frame of aether [as light]), strength of gravity at A and B will be different. Then, the orbit will warp.&#12298;P.S.&#122 99; Imagine a wave source and point A and B (distance from the source is the same) that are moving (on a straight line) on the surface of water. Power of waves that A and B receive is different.

Since: Jan 11

#5 Jan 18, 2011
General relativity indicates that changes in the gravitational field will propegate at the speed of light in a vacuum (c).

The accuracy in measuring the direction of the of a gravitational field is probably no where nearly accurate enough to measure the change you are talking about and it wouldn't help anyway.

The arc that the earth will form in 8 minutes is about 0.0055 degrees or about 20 arc seconds. But there is no linear motion anyway the earth is orbiting the barycenter between the earth and the sun (primarily - ignoring the other planets).

nakayama

Yokohama, Japan

#6 Jan 21, 2011
Thank you origin for your post. Yes, about gravitational force, i have never read the method to find the position from where it's "emitted".

If the light speed were slower and as a result, if apparent position of the sun (at the zenith) is the position that the sun was 6 hours before (in fact, it's the position that the sun was 8 minutes odd before), outline of the speed of gravity will be found. But a suitable heavenly body (to examine it ; under actual light speed ; including artificial body) may exist in our solar system .
[P.S.] Situation is also related to the rotational speed of the body and to the distance to the sun.
[P.S.] i must say sorry again. A post (date is 4 Jan 2011) seems to be valid partially.
nakayama

Yokohama, Japan

#7 Jan 28, 2011
If there is certain minimum limit (like quantum) in gravitational force, Seeliger's paradox (version of Olbers's paradox on gravity) will not stand up.

Since: Jan 11

#8 Jan 28, 2011
nakayama wrote:
To what precision, are we able to know the direction that gravitational force acts (for example, the sun's)? Possibly, it may exceed light speed ? Therefore it's untouched ?
You might find this interesting:
http://en.wikipedia.org/wiki/Speed_of_gravity
This site looks like it represents the current thinking.
nakayama

Yokohama, Japan

#9 Jan 31, 2011
Thank you for your instruction (difficult but interesting, e.g. Laplace's calculation). i have never seen such a site in Japanese.
nakayama

Yokohama, Japan

#10 Feb 7, 2011
Even on the ground, there will be apparatus that react to the gravity of the sun. When this apparatus turns (about 2000 seconds per one turn), the answer (to the speed of gravity) seems to be shown. Such a experiment will be one of laboratory experiments that "Encyclopaedia Britannica" mentions.
nakayama

Yokohama, Japan

#11 Feb 13, 2011
Apology and Withdrawal

Three posts (Jan 4, Jan 21 & Feb 7) are invalid. Very sorry. Allow me to withdraw.

[To administrator] If it's possible, erase the above and this post, please (i am thankful so much for opening [even to me] of this forum).
nakayama

Yokohama, Japan

#12 Feb 21, 2011
[Gravitational mass and inertial mass ; a monolog]

Allow me to ask. Are there any error in the following passage ?

A body (gravitational mass ; M) is hung from the roof by a string. Because of gravity of the earth, the string is tightened in a constant strength Mg. Above all are turned to the left a 90 degree angle. So, the roof is on the left and the earth is situated on the right (the earth is far. gravity is 1/100g). Now the string is cut, the body begins to "fall" to the right. To continue drawing from the right by a string (drawing force is 1/100Mg ; the earth vanishes) will be the same situation (if gravity is 1/99g, force 1/99Mg will cause the same acceleration as fall). The same acceleration (will be) by the same force. Namely, gravitational mass and inertial mass (of this body and of every body) will be the same.
nakayama

Yokohama, Japan

#13 Feb 26, 2011
[Equivalence principle & others]

Allow me to ask. Are there any error in the following passage ?

In the vacuum, it's said that many phenomena occurs. In it, there will be "substance" that is able to consider to be rest frame. Even Galileo's principle of relativity will be ideal, imaginary, convenient, partly and temporary. Much less, accelerated motion will be only relative in territory of numerical formulas (ignores change of momentum ; a vector quantity). The equivalence principle will be the same.

A elevator is accelerating to the above. At the center of (inside of) the elevator, a light source shines. Spherical waves of light reach floor earlier than roof. Is this the same in a elevator that is at a stand-still in gravitational field ?(scene like this is shown in a book in Japanese).
nakayama

Yokohama, Japan

#14 Feb 28, 2011
[Equivalence principle] Allow me to raise a hypothesis.

Inertial force will occur by the motion (excludes uniform linear motion) of a body relative to the aether frame. If it's true, equivalence principle is wrong. And every difficulty will be dispelled.

&#12298;P.S.&#12299; Gravity and inertial force act independently (Vector composition is possible in appearance). Both are reflection of different physical causes.&#12298;Differences &#12299; -Gravity- Not affected by the motion of body. Force that occurs in gravitational fields only. It occurs in inertial frames and in non-inertial frames. Not isotropic.-Inertial force- Affected by the motion of body. Force that is caused by external forces (includes gravity and centripetal force). Occurs only in non-inertial frames. Isotropic.&#12298;P.S. &#12299; In the air, a elevator is in free fall. Both forces are not the same.
nakayama

Yokohama, Japan

#15 Mar 1, 2011
Allow me to ask. Are there any error in the following passage ?

Inertial force of a hammer and gravity are equivalent ?
nakayama

Yokohama, Japan

#16 Mar 5, 2011
Mathematical expression of relativity of accelerated motion (without the rest frame) seems to be possible only between two rigid bodies (includes a case that the one is the universe). How do scholars grasp this ?
nakayama

Yokohama, Japan

#17 Mar 6, 2011
On every accelerated motion, there is its own cause (without exception). If an accelerated motion is relative, what about (the position of) this cause ?
nakayama

Yokohama, Japan

#18 Mar 7, 2011
Equivalence principle seems to deny momentum and the law of causality (causal relationship). If so, matters that are brought will be invalid.
nakayama

Yokohama, Japan

#19 Mar 8, 2011
If an elevator car (box) is high, strength of gravity at floor and roof is different. Equivalence principle will be wrong.
nakayama

Yokohama, Japan

#20 Mar 8, 2011
There is a space ship (regard inside as an elevator car). In this space ship, there is a man who is feeling 1g. Now he starts a jet engine in motion (jetted out downward ; power is weak). If 1g is caused by gravity, the space ship doesn't move (because power is weak ; at a stand still on the ground). But if 1g is caused by an accelerated motion, 1g will be increased somewhat. In short, equivalence principle seems to be wrong.

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