Registered Data

[CT151]

  • Session Time & Room
    • CT151 (1/1) : 3C @D404 [Chair: Yuzuru Kato]
  • Classification
    • CT151 (1/1) : Quantum theory (81-) / Biological fluid mechanics (76Z)

[02024] Quantum asymptotic phase function on the basis of Koopman operator theory

  • Session Time & Room : 3C (Aug.23, 13:20-15:00) @D404
  • Type : Contributed Talk
  • Abstract : The asymptotic phase function is a fundamental quantity for analyzing classical limit-cycle oscillators. In this study, we define the asymptotic phase function for quantum nonlinear oscillators by using the eigenoperator of the Koopman operator associated with the fundamental oscillation frequency. In an example of a quantum van der Pol oscillator with a Kerr effect, we demonstrate that the proposed asymptotic phase appropriately yields isochronous phase values in both semiclassical and strong quantum regimes.
  • Classification : 81-XX, 34L05, 92B25, Quantum synchronization, nonlinear dynamics, Koopman operator theory
  • Format : Talk at Waseda University
  • Author(s) :
    • Yuzuru Kato (Future University Hakodate)
    • Hiroya Nakao (Tokyo Institute of Technology)

[00978] Real-Time Krylov Theory for Quantum Computing Algorithms

  • Session Time & Room : 3C (Aug.23, 13:20-15:00) @D404
  • Type : Contributed Talk
  • Abstract : Here we describe the variational quantum phase estimation (VQPE) method, a compact and efficient real-time subspace algorithm to extract eigenvalues using quantum hardware. We theoretically and numerically explore a generalized Krylov scheme where the Krylov subspace is constructed through a parametrized real-time evolution, applicable to the VQPE algorithm as well as others. We discuss its application to fundamental problems in quantum computation such as electronic structure predictions for strongly correlated systems.
  • Classification : 81-08, 81-10
  • Format : Talk at Waseda University
  • Author(s) :
    • Katherine Klymko
    • Yizhi Shen (Massachusetts Institute of Technology )
    • Norm Tubman (NASA)

[01039] A model of cerebrospinal fluid flow in the cranial subarachnoid space

  • Session Time & Room : 3C (Aug.23, 13:20-15:00) @D404
  • Type : Contributed Talk
  • Abstract : Cerebrospinal fluid fills the subarachnoid space (SAS), which covers the spinal cord and the brain. During the cardiac cycle, it pulsates due to time-varying brain displacements. In this work, we study oscillating and steady streaming flow in cranial SAS in order to understand the mixing processes and waste clearance. We develop a theoretical model of the flow using lubrication theory. The model suggests that steady streaming plays an important role in mixing.
  • Classification : 76Z05
  • Format : Talk at Waseda University
  • Author(s) :
    • Mariia Dvoriashyna (University of Edinburgh)
    • Mariia Dvoriashyna (University of Oxord)
    • Alain Goriely (University of Oxford)

[02506] Hydrodynamic hovering of swimming bacteria

  • Session Time & Room : 3C (Aug.23, 13:20-15:00) @D404
  • Type : Contributed Talk
  • Abstract : The 'hovering' of flagellated bacteria near a rigid surface, i.e. stable swimming at a finite separation, has been studied experimentally and computationally but remains poorly understood physically. We use boundary element simulations to confirm existing results and to reveal that an elongated, as opposed to spherical, cell body is essential for hovering. We then derive and asymptotically solve a simplified model for the swimming cell and its near-field wall interactions, thereby elucidating the dominant physics.
  • Classification : 76Z10, 92C17, 76M45
  • Format : Talk at Waseda University
  • Author(s) :
    • Pyae Hein Htet (University of Cambridge)
    • Debasish Das (University of Strathclyde)
    • Eric Lauga (University of Cambridge)