2 ms·
It may help to add that the Plank length the smallest measurement of length with any meaning. It is about the limitations of describing positions, not an impli
by nyrikki 3y ago
It may help to add that the Plank length the smallest measurement of length with any meaning.
It is about the limitations of describing positions, not an implication that spacetime is discrete.
We don't know if spacetime is discrete, but we also have no evidence to suggest it is right now.
- danbruc 3y agoThat's not actually true, or at least it is not currently known. It is very well possible that distances less than a Planck length have meaning, or maybe distances lose all meaning a couple of orders of magnitude above the Planck length. We just don't know the physical laws at that scales. If you consider at what energy a photon (E = hc/λ) will be able to resolve, i.e. have a wavelength equal to, the Schwarzschild radius of that energy (r = 2GM/c² with E = mc²), then you get the Planck length up to a factor of root two [1], implying that measuring a Planck distance requires a photon so energetic that it turns that region into a black hole. If, very big if, the known laws still apply at those scales. [1] To get the Planck length, the wavelength must be doubled, i.e. be equal to the diameter instead of the Schwarzschild radius. r = 2GM/c² → m = rc²/2G → E = rc⁴/2G (with E = mc²) hc/λ = rc⁴/2G → hc/2r = rc⁴/2G (with λ = 2r) → r² = hG/c³ → lₚ = r = √hG/c³