Eugene Paul Wigner’s formulation [1, 2] of quantum mechanics in phase space is
completely equivalent to the ones by Werner Heisenberg, Erwin Schrödinger or Richard
Feynman but offers many insights into the inner workings of quantum theory usually hidden
behind the opaque curtain of the respective formalism. In the present talk we review some of
them having led to the construction of focusing wave packets in free space [3], or the
astonishing properties [4] of s-waves giving rise to measures of entanglement [5] based on
the negative parts of the Wigner function, and tunneling [6] analyzed from phase space
making contact with Unruh radiation.
References
[1] E.P. Wigner, On the quantum correction for thermodynamic equilibrium, Phys. Rev. 40,
749-759 (1932)
[2] W.P. Schleich, Quantum Optics in Phase Space, (VCH-Wiley, Weinheim, 2001)
[3] I. Bialynicki-Birula, M.A. Cirone, J.P. Dahl, M. Fedorov, and W.P. Schleich, In- and
outbound spreading of a free-particle s-wave, Phys. Rev. Lett. 89, 060404 (2002)
[4] J.P. Dahl, S. Varro, A. Wolf, and W.P. Schleich, Wigner functions of s waves, Phys. Rev.
A 75, 052107 (2007)
[5] J.P. Dahl, H. Mack, A. Wolf, and W.P. Schleich, Entanglement versus negative domains
of Wigner functions, Phys. Rev. A 74, 042323 (2006)
[6] D.M. Heim, W.P. Schleich, P.M. Alsing, J.P. Dahl, and S. Varro, Tunneling of an energy
eigenstate through a parabolic barrier viewed from Wigner phase space, Phys. Lett. A 377,
1822-1825 (2013)