Disprove string theory by empirically falsifying a string theory postulate. No postulate can be defended or it need not be postulated. Falsify BRST invariance and string theories collapse. Falsify the Equivalence Principle (EP) and the whole of physics needs a rewrite. No measurable observable violates the EP. All continuous and most approximately continuous symmetries bow to Noether's theorems.
You need an observable (so you know it is there) that is calculable (so you know how much) but not measurable, that is an absolutely discontinuous symmetry - and a test for its divergent consequences. Are shoes different from socks when given a left foot? By how much, yours versus mine? Quantitative chirality is calculated in any number of dimensions, J. Math. Phys. 40, 4587 (1999) and
Solution optical rotations ignore atomic mass distribution)
Chop a pair of shoes into mm^2 pieces. Sort them left versus right. Chirality is an emergent property. It depends on scale. To test the EP against a pair of shoes, one would need a shoe built on the smallest possible scale - a few atoms - and rather a lot of shoes to sum to a measurable divergence. Physics cannot do that, but chemistry can.
If anything can break string theory (we cannot be smarter than Luboš, but we can be orthogonal) then
Two geometric Eötvös experiments. 0.113 nm^3 volume/α-quartz unit cell. 40 grams net as 8 single crystal test masses compare 6.68×10^22 pairs of opposite shoes (pairs of 9-atom enantiomorphic unit cells, the test mass array cube's opposite vertical sides).
DO NOT bet your grade on that! Betting a December Swedish dinner is acceptable, especially if its main course is surströmming,
This post imported from StackExchange Physics at 2014-03-30 15:55 (UCT), posted by SE-user Uncle Al