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In the 1980s, the discovery of electron states that fractionalize in the presence of a time-reversal symmetry breaking magnetic field opened up new directions in condensed matter physics. In 2023, evidence has accumulated that a version of these states in which the time-reversal symmetry breaking is spontaneous appears in moiré materials.
In 2023, pulsar timing arrays announced what could become the first ever discovery of a stochastic gravitational wave background: the random superposition of gravitational waves permeating the cosmos — a vestige of cosmic processes in the Universe.
In 2023, a number of experiments on trilayer 2D structures uncovered new exciton states that have an electrically-tunable dipole moment and show a quantum many-body phase diagram.
Despite recent breakthroughs in quantum error correction experiments with trapped ions, superconducting circuits and reconfigurable atom arrays, there are still several technological challenges to overcome.
