RIKEN physicists suggest that a quantum property called ‘magic’ may be the key to understanding how spacetime came to be, based on a new mathematical analysis that links it to the chaotic nature of black holes.
Physicists link the quantum property of ‘magic’ to the chaotic nature of black holes for the first time.
A quantum property called ‘magic’ may be the key to explaining how space and time arose, a new mathematical analysis by three RIKEN physicists suggests.
It’s hard to think of anything more basic than the fabric of spacetime that underlies the Universe, but theoretical physicists question this assumption. “Physicists have long been fascinated about the possibility that space and time are not primordial, but instead come from something deeper,” said Kanato Goto of the RIKEN Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS).
A view of the M87 supermassive black hole. RIKEN theoretical physicist linked the chaotic nature of black holes to the quantum property of magic for the first time. Credit: EHT Collaboration
This notion received a boost in the 1990s, when theoretical physicist Juan Maldacena linked the gravitational theory governing spacetime to a theory involving quantum particles. In particular, he imagined a hypothetical space—which could be described as containing something like an infinite soup can, or ‘bulk’—that held objects like black holes acting through gravity. . Maldacena also imagined particles moving on the surface of the tin, controlled by quantum mechanics. He realized that mathematically a quantum theory used to describe particles at the boundary was equivalent to a gravitational theory describing black holes and spacetime within the bulk.
“This relationship implies that spacetime itself does not exist fundamentally, but emerges from some quantum nature,” said Goto. “Physicists are trying to understand the key quantum property.”
Kanato Goto and two colleagues conducted an analysis using wormholes that shed light on the black-hole information paradox. Credit: © 2022 RIKEN
The original thinking was that quantum entanglement—which binds particles together no matter how far apart they are—is the most important factor: the more entangled particles are at the boundary, the smoother the spacetime inside the bulk .
“But considering only the degree of disruption at the boundary cannot explain all the properties of black holes, for example, how their interiors grow,” said Goto.
So Goto and iTHEMS colleagues Tomoki Nosaka and Masahiro Nozaki looked for another quantum quantity that could be applied to the boundary system and could also be mapped to the bulk to describe black holes more fully. In particular, they noted that black holes have chaotic properties that need to be described.
“When you throw something at a[{” attribute=””>black hole, information about it gets scrambled and cannot be recovered,” says Goto. “This scrambling is a manifestation of chaos.”
The team came across ‘magic’, which is a mathematical measure of how difficult a quantum state is to simulate using an ordinary classical (non-quantum) computer. Their calculations showed that in a chaotic system almost any state will evolve into one that is ‘maximally magical’—the most difficult to simulate.
This provides the first direct link between the quantum property of magic and the chaotic nature of black holes. “This finding suggests that magic is strongly involved in the emergence of spacetime,” says Goto.
Reference: “Probing chaos by magic monotones” by Kanato Goto, Tomoki Nosaka and Masahiro Nozaki, 19 December 2022, Physical Review D.
DOI: 10.1103/PhysRevD.106.126009
