5 ms·

I never understood how gravity waves can go through anything and not be weakened? If the wave imparts energy on an object and makes it move, how is that energy

• neophyt3 5y ago
  I never understood how gravity waves propagate Mass causes gravity then what are these waves then? Is it dark matter thats not visible, not measurable and yet it has mass which causes ripple in space fabric
• p1mrx 5y ago
  It's possible to move an object, and return it to its original location, without expending energy. Ocean waves do this all the time. Based on conservation of energy, I would assume that friction can weaken a gravitational wave by turning some of its energy into heat. Though if we're talking about permanently changing the location of an object, that theoretically requires a negligible amount of energy... reminds me of the magic drive in https://qntm.org/frontier https://qntm.org/frontier
  • cobaltoxide 5y ago
    > Based on conservation of energy It turns out that energy is not conserved globally in General Relativity. https://math.ucr.edu/home/baez/physics/Relativity/GR/energy_gr.html https://math.ucr.edu/home/baez/physics/Relativity/GR/energy_...
• cobaltoxide 5y ago
  > If the wave imparts energy on an object and makes it move The objects don't move. The space between them stretches and compresses. Now, if the gravitational wave moves through a large massive object like a star or planet, the electromagnetic forces of the "stuff" in the object will cause it to resist this stretching or compressing. I think this does cause a very very very tiny "backreaction" to the gravitational wave, weakening it slightly.