Can I mimic gravity with Magnetism or angular momentum?
Do you mean something like this NASA centrifuge?
Yes and no, just curious about something. Light can be bent by gravity right? How fast should a centrifuge spin to have an effect on light?
In a practical sense, no. Even the mass of the sun bends light only a tiny angle. Large galaxies are needed to create gravitational lending where the bending of light is obvious.
So if you mean man made things and appreciable bending of spacetime, no. On the other hand, you can easily bend light with a lens.
Edit: typo fixed, bending rather than branding.
Currently it looks like 0.01 deg/h is the smallest optically detectable rotation.
As @anorlunda says, that is not from the curvature of spacetime
That 0.01 deg/h figure is far from the best we can achieve. We can do many orders of magnitude better using the same technique.
Excellent, what is the current limit?
The effect a centrifuge has on light is solely due to its motion. You can see the same effect in an elevator, where in an elevator-centered frame, light curves down. Unfortunately the degree of curvature is tiny (why we can still see in elevators), and it won't be much larger in a centrifuge.
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