5 ms·

So what is this really measuring? The curvature of spacetime between two points?

• contravariant 5y ago
  You're measuring a force. There's no real reason not to interpret it as one.
  • 8note 5y ago
    If you're measuring a force, you're measuring the force required to keep the two masses from coming together
    • kurthr 5y ago
      Actually, I agree... and while it's not clear that spacetime is a necessary complexity in this case, it is explicitly looking for quantum effects (e.g. the extra dimensions of string theory).
    • contravariant 5y ago
      Well yeah as is usually the case with inertial forces you're basically just measuring how difficult it is to keep something in place.
• steve76 5y ago
  I think of it as internally, where space and time converge to the same medium, each grain of gold has it's own filmstrip with very similar, yet still different frame rates. For example, the Sun is on a slower frame rate than the Earth. The Earth needs to do something in those frames yet still conserve spacetime. So the Earth orbits it. You floating in space are on a much faster frame rate than Earth. You might look like you are going to float by it. But you need to fill those frames while the Earth doesn't. You crash in, sync frame rates, and feel that impact. Those two grains are orbiting each other at really really small angles. It doesn't happen though as convection or electrical conduction fills the frames. There could be gravity applications, as in using a tremendous amount of energy, all the energy that exists, to generate a particle. That could be considered communication.
• jfengel 5y ago
  It's "really measuring" the deflection of a beam of light by a mirror connected to a wire connected to a weight. Everything else is a matter of modeling. The best model that explains all of the data is the Einstein Field Equations. The most useful way to interpret the model is to think of space and time geometrically (albeit a very weird kind of geometry in which one of the dimensions has the bizarre property that a straight line is the longest distance between two points). If you view it that way, the geometry acts as if it has intrinsic curvature: otherwise straight lines (like beams of light) don't go straight. So... it doesn't get to directly measure curvature. It's not even clear if it's meaningful to "really" measure curvature. Push on the whole notion of "measure" hard enough and it turns out that it's not nearly as clear as we think it is. Everything is "theory laden": a measurement is always a matter of interpretation, even the most straightforward ones. https://en.wikipedia.org/wiki/Theory-ladenness https://en.wikipedia.org/wiki/Theory-ladenness