I have heard it explained multiple time by different science educators that what we feel as gravity is a really just a consequence of curvature of spacetime and no real force is being applied. Why do we need to make gravity work with the standard model, and why are we looking for gravitons if there is no actual force and it is just caused by the geometry of the universe?
In: 66
Flip the question around backwards: why do we need relativity (or quantum mechanics) if Newtonian physics work just fine?
Answer: Newtonian physics work just fine when observing specific things. If you want to calculate the orbit of a planet around a star or the speed at which an apple falls from a tree, you can figure ~everything out without relativity or quantum. Now what if you ask ‘what holds the galaxy together?’ or ‘what’s happening inside of a proton?’. Newtonian physics can’t get you to a complete answer that matches the things we can see and measure at those massive or miniscule example scales.
It’s the same problem when you go the way you asked. If you take quantum mechanics and try to create a big many-equations computer model that shows how basic everyday stuff happens (like an apple falling towards earth), you’re either missing pieces you have to handwave or you get a result that isn’t what we can see and measure.
The reconciliation is the idea (which is debated and not proven) that if a set of equations and concepts cannot explain everything at every scale than it must be incomplete and/or incorrect in some way. Current models of quantum mechanics can’t explain all of those things without handwaving at least some parts (e.g., the carriers of gravity and how gravity works at extremely small scales).
Latest Answers