
#19
Sep2711, 03:29 AM

P: 42

All this example shows is that the same measurement if we attempt it from different reference frames will yield different results, which is rather the point of them, isn't it? Distances, speeds and times are not absolute, they are relative... which is why it is called relativity. You cannot say the distance is shorter, because that has no meaning. It only appears so from particular reference frames.




#20
Sep2711, 03:33 AM

P: 344

You can say that distance (for exsample near the Sun) mathematical and logical must be relative shorter, than for example here. 



#21
Sep2711, 06:13 AM

PF Gold
P: 1,376

G is global constant. And if it is global constant then locally it should be different at different gravitational potentials due to time dilation. Or maybe it is more reasonable to find out if it's GM product that's different or not and then talk about G and M separately. Gravitational time dilation should be real effect as you can observe it in static setup. I suppose that observations are consistent with distances being the same. Anyways question seems quite interesting. EDIT: Ah, but certainly speed is different from Mercury perspective due to time dilation. So the question is if it is enough to make picture consistent. 



#22
Sep2711, 06:22 AM

PF Gold
P: 1,376

Hmm, only it is performed in noninertial frame as almost all of the physics experiments. Then maybe discussion about inertial reference frames is not very useful? 



#23
Sep2711, 03:33 PM

PF Gold
P: 4,533





#24
Sep2811, 01:18 AM

P: 344

So when we measure the speed of the Sun to travel 250 km/s,  an observer on Mercury (or on the surface of the Sun) would measure it to be a little more than this?  is this what you saying ? If so Why ? Now imaging the same 2 observers measure the speed of a photon, we on Earth would measure it to be; “c”  would an observer on Mercury also measure that to be faster? Can the speed difference,  significant or almost completely solve the "mathematical meltdown" described above,  or is this value almost irrelevant in this context? Does the speed difference,  have anything to do with the cause of the the "mathematical meltdown" described above ? I mean is let’s say the mass of the Sun is exactly 2E30 Kg. Are you saying an observer on Mercury not would agree ? If so,  why? What about the mass of the Milkyway?  would the 2 observers also disagree ? Can the mass difference significant contribute to solve the "mathematical meltdown" described above,  or is it almost irrelevant in this context? Does the mass difference,  have anything to do with the cause of the the "mathematical meltdown" described above ? 



#25
Sep2811, 03:57 AM

PF Gold
P: 1,376

Let's try to put it down in less chaotic way.
As two observers observe the same sequence of physical events the only thing they can change is their representation of this sequence i.e. coordinate system. Relative time dilation between two observers is real as we can establish delay in sequence of signals with static distance. So first of all we have different scale for time dimension for two observers. Distances should be the same as speed of light locally is changing in a way that is consistent with unchanging distances. Result of this is that orbital speed around MW for observer on Mercury is faster by the same factor as time is delayed. Now we calculate GMproduct μ using the same formula for both observers. [tex]v_m^2=\frac{\mu_m}{r}[/tex] [tex]v_e^2=\frac{\mu_e}{r}[/tex] As speed is faster for Mercury observer but distances are the same for both observers we have that GMproduct is bigger by that speed scaling factor squared. As GMproduct have dimensions of time squared in denominator it seems that we have consistent picture so far. Now if we assume that G is the same for both observers then mass unit for Mercury observer should be smaller by speed scaling factor squared. This seems plausible as lowering mass in gravitational potential should convert part of the rest mass into kinetic energy. Does this reasoning seems fine? 



#26
Sep2811, 01:50 PM

P: 344





#27
Sep2811, 03:31 PM

PF Gold
P: 4,533

Temperatures Colors Ages Sizes Shapes Frequencies Pressures Forces Directions I'm having a hard time trying to think of something that wouldn't be put on the list. 



#28
Sep2811, 04:16 PM

P: 344

Ignore that the observers are orbiting different planet with different mass. And ignore the influence of SR Let's say the 2 clocks are orbiting the Sun without the planets Mercury and the Earth. One clock (A) 50 billion km away and the other (B) 150 km away. So the problem and the calculation shown above are still the same. Both observers would see the Sun complete 1 orbit of the Milkyway at the same time. But observer A would have "lost" 194,000,000 s. relative to B If the orbit speed of the Sun = 250 km/s for both observers / clocks,  observer A would calculate a shorter orbit of he Sun than B would  That would violate the laws of gravity. If the speed not was the same for both – (first I must ask WHY should it not ?) That would also violate the laws of gravity. And it would rise the question; how can the Sun move with 2 different speed ? So WHY can these 2 observers impossible agree about which measurement of the orbit of the Sun is the correct one? 



#29
Sep2811, 04:49 PM

P: 1,555

Perhaps you would like to explain a bit more by what you mean, for instance our meter is defined by the speed of light, however you claim the speed of light is everywhere the same even in locations with a different gravitational potential. But you at the same time claim that rulers are different lengths. 



#30
Sep2811, 05:01 PM

P: 42





#31
Sep2811, 05:35 PM

PF Gold
P: 4,533

I'm afraid I have made a big mistake. When I was getting ready to study your post #18, I went to the Thread Tools and used the "Show Printable Version" to print out your thread. The printable version did not print your graphic but instead showed the URL from which it was taken. So I go to www.science27.com and I see that you are promoting your own personal theory in violation of the forum rules. Bye, bye. 



#32
Sep2811, 11:08 PM

PF Gold
P: 1,376

First sentence in my explanation was: "As two observers observe the same sequence of physical events the only thing they can change is their representation of this sequence i.e. coordinate system." If you would use two clocks that tick at different speeds then with the same measuring rods your speed measurements will be different. 



#33
Sep2911, 01:28 AM

P: 344

I am NOT promoting my own personal theory in one single word. I am using my own webhotel to load graphics, and as you self wrote it was accidentally that you at all discovered that I had personally websites / theory. It sounds to me that you say; that only people that not have a personally theory are allowed to ask (skeptical) questions to science,  at this forum. I asked the question because I want to understand nature, as well as I want to understand my own theory. Is that really "forbidden" ? When "my thought" that something must be obvious wrong, with the way different observers understand the orbits (speed/distance) of the sun ,  you had have the change to lead me back to the right track, and you still have. But I am afraid such track even not exist. But I am not sure. 



#34
Sep2911, 01:49 AM

P: 344

Because we could say that the 2 clocks are following the Sun’s orbit around the Milkyway. (Technical we could say the orbiting clocks have devices (small rockets) on board to counteract the gravity from the Sun. Seen from our perspective both the Sun and the two clocks (all 3 objects) are therefore orbiting the Milkyway in the excact same radius to the center of the Milkyway) . The one clock is 50 billion km. behind the Sun, and the other 150 billion km. This should eliminate he last confusion according to the Special relativity influence, since all relative speed now are the same. Back to yours suggestion; As I understand you now I can only understand it like that speed not is comparable “the same” – which then also mean that also comparable distances not can be the same,  right? I think we have a serious mathematical problem here and wonder how such a simple obviously unsolved mystery possible can have existed the last 100 years without any explanation. ? I mean the math should be simple. We know the 2 relative time rates and I believe we also know the speed,  the logical result (so far I can understand it) hence should be that B impossible can travels the same distance, simple because speed multiplied with time = distance. I mean how difficult can that really be ? 



#35
Sep2911, 06:43 AM

PF Gold
P: 1,376

Two observers will come up with different numbers from their respective observations. Just because these numbers are different doesn't mean that they live in different worlds. It just means that they use different units for their measurements. In particular case it is time unit that is different. 



#36
Sep2911, 02:51 PM

P: 344

Or the gravity of the galaxy would not be the same for the 2 observers. That too would sound absurd. What should possible cause two different speed, or different influence of gravity? 


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