
#1
Dec1209, 08:40 PM

P: 6

Suppose two terrestrial objects B1 and B2 have concentrated a high quantity of mass while being reasonably separated by a distance. When a high speed rocket ship flies by in direction more less parallel to the line connecting these two objects, relativity must predict a drastic disturbance in the physical state between B1 and B2. Not only the mass of each of the two objects is seen increased as moving mass by someone in the rocket ship according to relativity, but also the distance between B1 and B2 found shortened by the observer. Gravitational force between them must be predicted by this theory to increase many folds. Indeed, if relativity is valid, the increase is by a factor of {1/[1(v/c)2]1/2}4
(2, 1/2, and 4 are all in superscript)! Gravitational force thus escalated must force these two objects to collide, or at least to be predicted as having much higher potential of ultimately colliding by this observer. Does relativity reveal what kind of physical effect that a flyby rocket ship can exert on these two objects? Or does relativity have paragraph rewriting Newton’s equation of universal gravitational force in a moving person’s observation? 



#2
Dec1209, 08:50 PM

PF Gold
P: 363





#3
Dec1309, 12:14 AM

PF Gold
P: 4,081

Gravitational effects are observer independent. That is why general relativity is written in terms of tensors or an equivalent formalism. 



#4
Dec1309, 02:44 AM

P: 6

Gravitational force vs. relativityBesides, does relativity proposes that gravitational effects are observer independent and tell people why it should? 



#5
Dec1309, 02:54 AM

P: 6





#6
Dec1309, 07:08 AM

Math
Emeritus
Sci Advisor
Thanks
PF Gold
P: 38,879

Once again the moving observer would observe an increase in mass of the two objects and a decrease in the distance between them. An observer in the rest frame of the two masses and the two masses themselves would see no change in mass, distance, or gravitational force.




#7
Dec1309, 07:51 AM

Mentor
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#8
Jan110, 12:17 PM

P: 6

[QUOTE=DaleSpam;2489480].I don't believe this is true.QUOTE]
The truth is only a simple concept of reflection, although how precisely the reflection works out does require math. However, math steps in after physiccal explanation not before. Possibly a primitive man can explain why he sees himself while staring at water ssurface. When Archimeda used concave mirrors to burn enemy's ships, possbibly (it means I do not say this with certainty) he had not figured out the mathematical relationship between curvature of the reflecting surface and the focus point. 



#9
Jan110, 06:22 PM

Mentor
P: 15,571

I don't understand where you're going here. You posted an equation that turned out to be wrong, and now you seem to be complaining that things get quantitative too soon.




#10
Jan110, 09:14 PM

P: 6





#11
Jan110, 09:16 PM

P: 6

Ah, after I complain, I see I can quote you clearly. But it is ok. I will come back some other time. Thank you.




#12
Jan110, 11:24 PM

Mentor
P: 16,472




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