It's easy to see how matter interacts with itself but how does it interact with spacetime which is "not" matter?

Einstein showed us that mass and energy cause a curvature in spacetime, which intern causes gravity, but how does a body "follow" these curves if it "passes through" spacetime?

In other words what makes spacetime and matter touch?

  • $\begingroup$ As your question is worded, it is unclear what you are asking, and it may potentially be a duplicate. See: physics.stackexchange.com/questions/116608/… and physics.stackexchange.com/questions/109731/…. $\endgroup$ – JamalS Oct 30 '14 at 23:18
  • $\begingroup$ I don't think these questions reflect the nature of mine, the first one asks more about what particle, the second refers to the measurement of curvature. Mine, however, asks about the interaction between matter and spacetime. $\endgroup$ – Investor Oct 30 '14 at 23:25
  • $\begingroup$ As far as I understand, the Einstein Field Equations are what makes them "touch". If you ask someone with more knowledge of quantum gravity than me, their day job is to describe in more detail how this "touch" happens: they are seeking the Einstein Field Equation analogue of the atoms that underlie the macroscopic equations of continuum mechanics and thermodynamics. In other words, your question is what a whole phalanx of theoretical relativists and string theorists is devoting their lives to. So its a deep question, and not readily answered in anything less than a book. $\endgroup$ – Selene Routley Oct 30 '14 at 23:40