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Quantum swimming. Boris Gutkin, David Oaknin. Q. Q-Swimming. Swimmer in a quantum sea: Photon bath Fermi sea. C-swimming competition. Shape space=Control space. Swimming stroke=closed path in shape space. Euclidean motions. Shape space. swimming. Swimming: definition.
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Quantum swimming Boris Gutkin, David Oaknin
Q Q-Swimming Swimmer in a quantum sea: Photon bath Fermi sea
C-swimming competition Shape space=Control space Swimming stroke=closed path in shape space
Euclidean motions Shape space swimming Swimming: definition Swimming: a map
Untethered scatterers Balanced scatterer
qswimming Euclidean motions Q-Swimming Qswimmer: a unthethered balanced periodic scatterer Scattering matrices Need: a principle to fix the location and orientation of balanced scatterer
Swimmer=scaterer 1-d quantum medium Swimming in one dimension r t On-shell scattering matrix The swimmer controls the scatteringbut not its location
Velocity of ball Force on ball Friction coeff C-Swimming: The role of friction mutual forces
Control and response One unknown, the position X. Equation of motion: equilibrium
Swimming in geometric Swimming: when dX does not Integrate to a function
The invisibility principle 1-d Fermi sea, T=0 The position adjusts so that the medium will think nothing has happened
Quantized swimming 1-d Fermi sea, T=0 r-plane Control space Points of transparency
Toolbox Avron, Buttiker, Elgart, Gutkin, Graf, Oaknin, Pretre, Sadun, Thomas
Energy shift Dual to Wigner time delay Ex: in 2 channel case: sink snowplough Avron, Elgart, Graf, Sadun
H Key formula r Avron, Elgart, Graf, Sadun
Quantum friction Momentum transfer to medium
Swimming equation Total force on swimmer vanishes
Conceptual issues Avron, Buttiker, Elgart, Gutkin, Graf, Oaknin, Pretre, Sadun, Thomas
(E,t) as a canonical pair A function of non-commuting variables A canonical transformation of half-line E p t x Avron, elgart, graf, sadun
Phase space A function of non-commuting variables E t