Physics Colloquium: "Quantum Supreme Matter"

What is the nature of matter? The pursuit of the quantum computer has raised the awareness of the central role of many body entanglement. One discovers that the matter of the high energy- and condensed matter textbooks is not entangled at all in the thermodynamic limit, forming the fundament of the semiclassical description with its particles, spontaneous symmetry breaking and so forth. But should all matter be of this kind? In fact, dealing with strongly interacting fermions the fermion sign problem interferes insisting that its description requires the supremacy of the quantum computer because of the dense entanglement. The properties of such “quantum supreme” matter should be governed by physical principles of a new kind. The progress is due to a mathematical machine discovered in string theory – the AdS/CFT correspondence – computing the properties of densely entangled matter by mapping it to black hole physics in one higher dimension.  The outcomes suggest a set of new principles such as the “Planckian dissipation”, quantum-critical phases governed by a novel type of scaling laws, automatic “intertwinement” of order and a lot more.  The guinea pig for this kind of physics are the cuprate high Tc superconductors, an affair that evolved into the big mystery of condensed matter physics.  In a series of recent experimental developments evidences have been accumulating that this stuff is actually governed by the quantum supreme matter principles.

Bio: Jan Zaanen is theoretical physics professor at Leiden University, The Netherlands who is well known in condensed matter physics given his ZSA classification of Mott insulators, DFT+U band structure method and the discovery of electron stripes while his present interests are at the interface with high energy physics and string theory. Among others, he is Spinoza laureate (the “dutch nobel prize”) and fellow of the dutch royal academy of sciences.