Month: September 2022

LONG PERIODS. “Such a system has been shown to exhibit dramatic breaking of discrete time-translation symmetry in which the bouncing atoms can evolve with periods up to about 100 times longer than the period of the drive.” https://lnkd.in/e5UXiem5 View in LinkedIn

NEW POSSIBILITIES. “This allows the creation of big discrete time crystals possessing a large number of temporal lattice sites, which are suitable for realizing a broad range of condensed matter phenomena in the time dimension.” https://lnkd.in/e5UXiem5 View in LinkedIn

DURABLE. “Such discrete time crystals are robust against external perturbations and quantum fluctuations and live for extremely long times.” https://lnkd.in/e5UXiem5 View in LinkedIn

PREDICTED PHENOMENA. “Temporal condensed matter phenomena that have been predicted to date include Mott insulator phases in the time dimension: Anderson localization and many-body localization in the time dimension; topologically protected edge states in time; quasi-crystal structures in time; two-dimensional time lattices supporting a Möbius strip geometry and flat-band physics; and time-space crystals exhibiting a six-dimensional quantum Hall effect.” https://lnkd.in/e5UXiem5 View in LinkedIn

EXPANSION. “The second quantization formalism allows us to switch from a single particle to many indistinguishable particles by introducing the bosonic field operator ψˆ, which can be expanded in terms of operators that annihilate a boson in time-independent single-particle basis states.” https://lnkd.in/e5UXiem5 View in LinkedIn

SPONTANEOUS SPACE CRYSTALS. “Spontaneous breaking of continuous space translation symmetry into discrete space translation symmetry results in the formation of ordinary space crystals.” https://lnkd.in/e5UXiem5 View in LinkedIn

NON-SPONTANEOUS SPACE CRYSTALS. “However, crystalline structures in space can also be created externally without any spontaneous process.” https://lnkd.in/e5UXiem5 View in LinkedIn

PHOTONIC CRYSTALS. “For example, by imposing periodic behavior of the refractive index in space in dielectric materials, one obtains photonic crystals in which the propagation of electromagnetic waves possesses similar properties to the transport of an electron in a space crystal.” https://lnkd.in/e5UXiem5 View in LinkedIn

ULTRACOLD ATOMS. “Another example is ultracold atoms in optical lattice potentials which are routinely created in the laboratory by means of electromagnetic standing waves. There, ultracold atoms behave like solid state systems but the crystalline structures in space do not emerge spontaneously.” https://lnkd.in/e5UXiem5 View in LinkedIn

SO ENDS this first of two weekends on the theme of time crystals. The ideas presented here are not entirely new, and come in part from Nobel prize winner Philip Anderson, the “pope of solid-state physics.” Condensed matter physics is the closest thing we have on Earth to investigating extreme conditions in outer space, with enormous densities, magnetism, heat, and cold, that likely require new physics to describe them. https://lnkd.in/e3uyixHV View in LinkedIn