When nature entangles millions of particles: from quantum materials to black holes
Subir Sachdev (Harvard Univ.)
Entanglement is the strangest feature of quantum theory, which Einstein called ''spooky action at a distance’’. Quantum entanglement can occur on a macroscopic scale with millions of electrons, leading to "strange metals" and novel superconductors which can conduct electricity without resistance even at relatively high temperatures. Remarkably, related entanglement structures arise across the horizon of a black hole, and give rise to Hawking’s quantum paradox. I will describe a toy model of many-body quantum entanglement which has shed light on these distinct phenomena at very different distance scales.