  Quantum nonlocality which is conventionally invoked for describing a
composite entangled system is shown here to be a possible important
characteristic of a single quantum object. To this end, we analyze some
interactions of a single photon released from Fabry Perot resonator with
environment. The split photon state with oppositely moving parts is shown to
obey quantum nonlocality despite the sharp edges truncating each part. Photon
post release reflection from a plane mirror is considered. The changing shape
of the form during reflection contains moving discontinuities in electric and
magnetic components of the pulse. They originate from preexisting edges of the
form and move together, first away from and then back to the mirror. At the end
of the process, the pulse restores its original shape, with electric component
reversed. Altogether, the process demonstrates conservation of moving
discontinuities. The considered experimental setup may be used for some new
versions of a delayed choice experiment, with various options for insertion of
detectors and the respective time delays. In all cases, the delayed insertion
does not have any retroactive effect on the process.
  Key words: Evolution operator, signaling, reflection, discontinuity, quantum
nonlocality
