
nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 2 2016, 12:38 AM 
Two elevator cabins are falling. One is in a free fall and the other is falling on rails that are set on a face of steep slope (no friction). Each instrument shows value 0g and 0.1g (0.1g is not the value shown in the vertical direction). Equivalence principle is difficult to accept. By the way, value shown on the rails is 1g.
At everywhere of space, a surveillance network on acceleration, deceleration is spread. None can avoid. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 3 2016, 2:38 AM 
My conclusion
When a position of bodies is the same, gravity acts with the same g. At this position, gravity acts independently of the motion of bodies. In free fall also.
Inertial force is caused by acceleration (including deceleration) of bodies. At everywhere of space, a homogeneous mesh of net is spread and all follows (qualitatively, quantitatively). There is no exception. The net is sure. Yes, the same acceleration brings the same g and about it, gravity does not act at all. In free fall also. 

Anonymous
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 3 2016, 9:11 PM 
Additional (To yesterday's post)
1 ”a position of bodies is the same” means ”a position of bodies in a gravitational field is the same”.
2 In free fall, the role of gravity is confusing, at a glance. But inertial force, acceleration both show concrete values. Gravity is only one of causes of acceleration. It’s role is secondary. Other forces can cause the same acceleration and inertial force. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 5 2016, 12:45 AM 
An elevator cabin that was hung with a rope is now falling in free fall. Tension of the rope is 0mg. Well, it is possible to control (in principle) this tension. Tension is controlled to be 0.2mg, 0.4mg, 0.6mg and 0.8mg. It will be natural to see that in all, the same gravity g is acting. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 6 2016, 11:44 PM 
An elevator cabin is hung by a crane. At the side of it, the second elevator cabin is passing in free fall. Passing speed is measured. This value is different from the value that was measured when the moon was just above. This difference can be explained with the gravity of the moon. On falling elevator cabin, gravity of the earth is acting also. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 7 2016, 12:51 AM 
It is said that gravity is waves and the speed is light speed. Then, in an elevator cabin in free fall, how about these ? 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 8 2016, 12:40 AM 
Allow me to write frankly.
In discussion on free fall, a starting point of falling, center of the gravity (center of the gravity source) cannot be ignored. When these are lacking, we will be unable to start talking. By the way, in free fall, acceleration, inertial force are selfevident, I believe. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 9 2016, 1:05 AM 
On the ground, an elevator cabin is accelerated with a rope to the left. Tension of the rope is 1.2mg. Next, this cabin is accelerated upward with a rope. Tension is the same 1.2mg. In this cabin, the same 1.2g is measured also. But, length of rope that was winded onto a reel will be different. 

makayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 10 2016, 9:03 PM 
In a space ship windowless, acceleration downward g is measured. The crew can vary the direction of the space ship (direction of center line relative to the celestial sphere). The crew will be able to show whether g is caused by gravity or by jet of the space ship.
But, the thing of this level will be written somewhere. Or, is it my misunderstanding ? 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 12 2016, 1:04 AM 
There is a picture with two small rockets. One is at a standstill on the ground and the other is accelerating upward vertically (in outer space). But, as shown in free fall, accelerated rocket is possible to draw parabola (If a condition of uniform linear motion of an observer is satisfied). A rocket on the ground is impossible.
Suppose that in gravitational sphere of the earth, the second rocket is in accelerated motion in various direction and at various g. Equivalence principle will be wrong. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 14 2016, 12:31 AM 
There is a picture with two small rockets. One is at a standstill on the ground and the other is accelerating upward vertically (in outer space). On the floor of each, acceleration 1g is acting. Now, an engine (the second engine) of each rocket starts. Propulsive force by jet downward is 1.2mg. Acceleration acting on the floor will be 1.2g in the first rocket and 2.2g in the second rocket. Gravity and inertial force will not be the same. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 14 2016, 12:31 AM 
There is a picture with two small rockets. One is at a standstill on the ground and the other is accelerating upward vertically (in outer space). On the floor of each, acceleration 1g is acting. Now, an engine (the second engine) of each rocket starts. Propulsive force by jet downward is 1.2mg. Acceleration acting on the floor will be 1.2g in the first rocket and 2.2g in the second rocket. Gravity and inertial force will not be the same. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 15 2016, 3:39 AM 
On the ground, g is acting. On the other side of the earth, it is the same. These two positions are not in accelerated motions that can explain this g. Gravity and inertial force will not be equivalent. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 18 2016, 1:43 AM 
Some books deny relativity of accelerated motions. Some books seem not to deny. The latter will mean the denial of inertial frames. But it is not mentioned. The counterattack will be afraid of. Inertial frames will deny a picture of a free fall. (local area will not be a refuge).
On a body, acceleration g is acting. From the circumstances, when cause is impossible to be gravity, it is inertial force and when cause is impossible to be inertial force, it is gravity. Namely, equivalence principle will be impossible (if there is only one case that shows the cause of g, equivalence principle will be impossible). 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 18 2016, 9:13 PM 
Three elevator cabins start free fall. There is the interval of 0.1 seconds at the start time. How does relativity explain ? 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 18 2016, 10:34 PM 
On three elevator cabins each lined up on the ground, acceleration 1 g, 2 g and 3 g acts. After certain time, the position from the starting line will be 0a, 1a, and 2a. If the starting line is accepted to be an inertial frame, the explanation will be possible only by gravity. By the way, position of a falling body (in free fall) is shown by formula 1/2gtt. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 19 2016, 9:12 PM 
Without conviction, I try to write a view. Apologize if it is wrong.
In Wikipedia (in Japanese), the equivalence principle is also written as follows. “In the infinite small area, acceleration of motion and of gravity cannot be distinguished". However, in general, vector of the two (the two are calculable) are different (unrelated than different : qualitatively and quantitatively). Even in the infinite small area (locally), it will be so (in general). A case that the two is difficult to distinguish is exceptional and is limited only to a point, to a line or to a plain. Why is that a principle ?
Apology : In yesterday's post, a word "upward" was left out. Acceleration acts upward. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 20 2016, 12:10 AM 
P.S. (to Dec 18)
To grasp a free fall, position inside the cabin is not suitable. All can be grasped from the outside. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 20 2016, 11:42 PM 
On a plane, plural bodies are moving in uniform linear motions (inertial motions). It is possible to suppose that one of these bodies is at a standstill and is possible to rewrite motions of other bodies. But it will be impossible on plural bodies in moving in accelerated motions. Relativity of accelerated motions will be impossible. Free fall will not be inertial frame. 

nakayama
 Re: The Equivalence of Acceleration and Gravitation in General Relativity  December 22 2016, 1:39 AM 
Does principle of gravity and inertial force acting on a body differ according to the size of body ? Why infinite small area is specialized ?  

 
