Permanent Chaos: How Disorder Emerges in Static Quantum Systems ⚡ экспресс
Quantum chaos is associated with the emergence of random matrix statistics. The spectral form factor (SFF) shows a universal linear ramp. The result by Bertini, Kos, and Prosen (BKP) proved the existence of a ramp for dual-unitary qudit circuits. Building on BKP and a variant of the Feynman–Kitaev clock construction, a ramp is obtained for static geometrically local Hamiltonians: the Floquet quasienergy spectrum of a dual-unitary circuit is embedded into the energy spectrum of a static Hamiltonian, and its associated SFF inherits the BKP ramp in a symmetry sector. This is the first proof of a ramp in a static, geometrically local many-body system with finite local Hilbert space dimension.
In the mid-20th century, physicists noticed something odd: the energy levels of complex atomic nuclei behaved like lottery balls — completely unpredictable. Since then, the search for such hidden chaos in the microworld has never stopped. Until recently, it was thought that chaos only appeared in systems that are constantly pushed, like a blender. But now scientists have managed to prove its existence in a completely static quantum system — they used a trick proposed long ago by Feynman and Kitaev: a quantum clock mechanism. It's like sewing an internal metronome into a static structure — the system itself doesn't change, but its energy pattern bears the imprint of chaos. This same pattern, reminiscent of the echo of a distant explosion, has long been known in black hole physics, hinting at a deep connection between gravity and quantum mechanics. This discovery helps explain why heat spreads so quickly even in insulators, and why the spectra of complex atoms remain stable despite internal disorder.
🎯 Energy levels of atomic nuclei behave like winning lottery numbers — completely random. This opened physicists' eyes to quantum chaos.