Why Doesn’t Gravity Happen Instantly?
forbes.com
forbes.com
With a slingshot maneuver, why does the the direction of the inertia change though? If you zoom out far enough the lines are mostly parallel with a "dip" where there as mass. Why can an object enter parallel to a line, be dragged with the line towards the mass, miss it and exit on a path not aligned with a line? https://i.imgur.com/qj8fafd.png
Also that image doesn't show the slight twist in the grid caused by the earth's rotation. Another part of the video does though.
I would assume that all of the forces have to be delayed. Being a force, inherently in relation to some other thing, there’s a transfer that has to occur for the force to interact. That has to travel through space. Even in my (admittedly lay) understanding that we don’t have a full explanation of gravity, I would assume it’s subject to those same basic (spatial) principles.
Is that assumption way off base?
And we distinguish signals from noise via a few different approaches, but our flagship search relies on matched filtering against simulated waveforms, and requiring the same signal to be coincident in time across multiple, geographically-distant detectors for which very few noise sources are correlated.
First, we observe that [quantum radiation pressure noise] contributes to the motion of the kilogram-scale mirrors of LIGO. This observation is also made in the Advanced Virgo GW detector. It is remarkable that quantum vacuum fluctuations can influence the motion of these macroscopic, human-scale objects, and that the effect is measured. This is quantum mechanics at its experimentally most macroscopic scale.
There's some great info in this[2] paper about the detector, sensitivity and performance of Advanced LIGO. And yeah it blows my mind every time I think about it.
[1]: https://arxiv.org/abs/2002.01519
[2]: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.102.0...
They do, at least obliquely. In summary: the issue is that if everything else about Newton’s model was right except that gravity was delayed, orbits would be wrong. But, actually, it turns out, as Einstein theorized and later evidence supported, everything (well, enough) else about Newton's model turns out to be wrong, too.
light has no resting mass thus is not limited to sublight speed due to this lack of mass.
in this scenario the limitation is about the maximum deflection/distortion rate of spacetime, thus spacetime distortion can not occur at a rate faster than light speed.
if spacetime is distorted beyond this curvature you get a black hole, and if a blackhole is smaller than the schwarzschild radius it spontaneously collapses and backlashes into ultrahigh energy photons[gamma rays]
The weirdest part is that there are photons that are currently receding away from us faster than the speed of light but they will still be able to reach us eventually anyway.