Science Alert  October 5, 2019 An international team of researchers (Austria, Switzerland, Germany) has demonstrated the interference of a molecular library of functionalized oligoporphyrins consisting of up to 2,000 atoms, by far the heaviest objects shown to exhibit matter-wave interference to date. They realized quantum superposition of these massive particles by measuring interference fringes in a new 2-m-long interferometer that permits access to a wide range of particle masses with a large variety of internal states. The results show excellent agreement with quantum theory and cannot be explained classically. The interference fringes reach more than 90% of the expected visibility […]