## Curves in Space and Time vs. Banks on Roads and Race tracks

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### Curves in Space and Time vs. Banks on Roads and Race tracks

Engineers design banks on winding roads and race tracks to prevent vehicles travelling within "safe" speed from flying off the road. Similar results can be achieved if upon speeding through the winding portion of the road, vehicles are tethered to an imaginary rope.

In the universe, the pull exerted by the mass of the inferred existence of dark matter is similar to the imaginary rope. How about the curves in space and time? Do they provide the same effect as the banks on winding roads?
ErnieM
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### Re: Curves in Space and Time vs. Banks on Roads and Race tra

I'm not absolutely sure what you mean by winding roads. I googled "winding road", and got, among other pictures, this one:

This winding, right-and-left-and-right-again and so on is clearly another sort of "path" than an ordinary orbit:

The Moon is in orbit around the Earth, or rather, the Earth and the Moon are in orbit around their common center of mass. Obviously the orbit is much, much larger compared with the size of the Earth and the Moon than this picture suggests. Still, the orbit is a relatively simple "one-way-curve", not a "winding road".

But in space, a "winding road" would be possible. It would all have to do with the distribution of mass and the subsequent "curving" of spacetime. According to Einstein, spacetime is curved by the presence of mass in it. There is a local curvature caused by the local distribution of mass, and there is an overall curvature, depending on the total mass of the universe. Objects moving in space follow the shortest path in space, and the shortest path is defined by the local curving of spacetime.

I googled "curved spacetime" and found, among other pictures, this one. What I like about it is that it shows that spacetime can be curved in a complicated way, with many local peaks and valleys. It should definitely be possible for spacetime to be curved in such a way that an object passing through the area might be tracing a "winding road", at least for a limited time.

And I really think you could describe the "curves" of spacetime as somewhat similar to banks of winding roads.

Ann

Ann
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### Re: Curves in Space and Time vs. Banks on Roads and Race tra

Note that non-relativistic (Newtonian) gravitation motion is only due to the General Relativistic curvature of TIME (NOT SPACE )

[Non-relativistic (Newtonian) bodies move rapidly through TIME but NOT SPACE.]

Relativistic (non-Newtonian) gravitation motion is also due to the curvature of SPACE which results in a precessional advancement of the perihelion due to an augmentation of effective radial forces near the origin (i.e., r=0):

Quasi-elliptical orbits in the wishing well funnel examples here result in a precessional retardation of the perihelion (at least initially) due to a maxing out of the effective radial forces at a funnel slope angle of 45º.
Art Neuendorffer

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