Quantum Effects

Even if quantum physics is well established since roughly ninety years, there are still some quantum effects in matter which have been theoretically predicted but up to now not yet seen experimentally. It was the physicist Hans Bethe, who first described theoretically in 1931 what happens in a one dimensional quantum spin system: under certain conditions, magnetic  excitations may interact and give rise to a collective excitation, known as “Bethe strings”.  But in real matter, strictly one dimensional systems are rare, so Bethe strings have not been a common phenomenon. Now those Bethe strings have been discovered for the first time experimentally by the AugsburgRead More →