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  • 1H H Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.

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This summary is machine-generated.

Quantum wavefunctions can become knotted, similar to DNA. Researchers found that the probability of vortex knotting increases with length, suggesting these structures are common in complex wave systems.

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Area of Science:

  • Quantum physics
  • Topology
  • Complex systems

Background:

  • Macroscopic tangles, like DNA, are common.
  • Knotting is a topological property observed in classical systems.

Purpose of the Study:

  • To investigate knotting in quantum wavefunctions.
  • To explore the occurrence and characteristics of vortex knots in quantum systems.

Main Methods:

  • Computer simulations of random superpositions of degenerate eigenstates.
  • Analysis of three quantum systems: a cube with periodic boundaries, a 3D harmonic oscillator, and the 3-sphere.

Main Results:

  • Knotting occurs in quantum wavefunctions, with tangled filaments being vortices (nodal lines/phase singularities).
  • The probability of vortex loop knotting increases with its length.
  • A wide variety of knots were observed, constrained by spatial symmetries in some systems.

Conclusions:

  • Knotted vortex structures are generic in complex three-dimensional wave systems.
  • Establishes a topological commonality between wave chaos, polymers, and turbulent Bose-Einstein condensates.