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This is a question, where I start with some assertions:

Try to consider the universe as a four-coordinate system, x,y,z,t where t is time and where we view a change in t as a change in position, and as a velocity in the same way as any other change in either of the other components of the coordinate. Everything is then moving at the speed of c. The difference between a photon and another particle would be that a photon "spends" its velocity in any of the x, y or z dimensions - but not in the time dimension.

This implies that all photons are on the same coordinate in the t-dimension - only the x,y,z values change while t remains 0. It also implies that time would appear to stop for something travelling in only the other dimensions, while it would pass fastest for something completely stationary.

You can then also consider space-time as a function of acceleration. A physical objects' coordinate could be derived from its velocity, which would have to be derived from its acceleration. Acceleration would be a function of entropy, or "age" I believe.

Is this the basis of general relativity? Is it at least an initial starting point for general relativity, or is it completely wrong?

Would spin have to be part of the coordinate system?

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closed as too broad by Alexey Bobrick, Eduardo Serra, astromax, TildalWave, called2voyage Jan 13 at 16:10

There are either too many possible answers, or good answers would be too long for this format. Please add details to narrow the answer set or to isolate an issue that can be answered in a few paragraphs.If this question can be reworded to fit the rules in the help center, please edit the question.

    
No, it is completely wrong. Everything about this is mistaken. The first mistake is confusion between four-velocity and speed, aided by ignorance of the metric. Sorry, but I don't think this is salvageable. –  Stan Liou Jan 10 at 12:28
    
@StanLiou It would be better if you could help him understand instead of just saying he's wrong –  Eduardo Serra Jan 10 at 13:19
    
@StanLiou Can't you just help me and provide one observation or calculation where this view does not match? I allows my intuition to explain Einstein shift and relative time, and why nothing can move faster than the speed of light, it even explains the twin paradox in an intuitive way. –  frodeborli Jan 10 at 13:25
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@frodeborli: The problems in your question start with the sentence "Everything is then moving at the speed of c." and continue further on. If you explained what you mean in terms of 4-velocities, world lines and 4-dimensional spacetime, it would perhaps be easier to understand your question. All these notions are standard and are explained in most introductory books. –  Alexey Bobrick Jan 10 at 17:33
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@EduardoSerra: I provided two things he should start with to understand this better, but I obviously can't teach someone GTR in a comment section. So what's the problem? –  Stan Liou Jan 10 at 21:47
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1 Answer 1

up vote 2 down vote accepted

I think, you are trying to describe a world line.

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Excellent answer! I really struggled in the comment section above... :) And then I can use vector calculations to calculate a lot of stuff such as Einstein shift etc I guess. I just express velocity as a function of mass and energy, derived from 0.5mv^2=E? And define everything to have velocity of c in 4D. As you know I am not a physicist, so I ask a lot... :) –  frodeborli Jan 11 at 1:16
    
@frodeborli: That's not the correct relation. The correct relation is $(mc^2)^2 = E^2 - (pc)^2$, which is has the geometrical meaning of mass being the magnitude of the four-momentum vector. –  Stan Liou Jan 11 at 2:44
    
@StanLiou Magnitude? Then I am getting This world line wring, still. The magnitude would, as I see it always be c in four velocities. Then I want to apply an acceleration inversely squared by the distance to another particle, on the time dimension. –  frodeborli Jan 11 at 14:16
    
I am unsure of how to apply the acceleration on the four vector yet, but I assume it'll be possible. –  frodeborli Jan 11 at 14:25
    
@StanLiou I think I get it. Four-momentum is just four velocity but with mass-energy. But energy is derived from among other things, velocity in three dimensions, ignoring time. –  frodeborli Jan 11 at 14:31
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