(December 10, 2016 at 4:53 pm)Alex K Wrote:(December 10, 2016 at 11:14 am)RozKek Wrote: If there are more dimensions than 3, is it even possible to detect them somehow, to find out that they actually are.
Absolutely, depending on what their properties are. First of all, if they are curled up (and that's the most common assumption to render them invisible to everyday experience), how and whether they can be detected experimentally depends on two factors:
1. which fields and particles can move in them
2. how large they are
If none of the known particles, but only gravity, can actually propagate through the extra dimensions, they must be relatively large to be noticed in experiments such as the LHC (for example, if there are two extra dimensions in which none of the known particles can move, they must be of micrometer size to be visible in next generation colliders)
If some of the known particles can move in the extra dimensions, possibly all of them, this means that everything including ourselves is spread out in the extra dimension(s) via quantum uncertainty. The fields which move in the extra dimensions can form resonances much like the acoustic standing waves you notice at certain frequencies in a small room. In particle physics, those resonances manifest as a repeating pattern of heavier copies of the existing particles, calles "Kaluza-Klein-Modes". Searches for such extra-dimensional resonances are ongoing at the LHC, but so far haven't yielded results.
Wow, thanks. This was actually really cool and interesting, is this theoretical physics?