  We experimentally demonstrate a non-local generation of entanglement from two
independent photonic sources in an ancilla-free process . Two bosons (photons)
are entangled in polarization space by steering into a novel interferometer
setup, in which they have never meet each other. The entangled photons are
delivered to polarization analyzers in different sites, respectively, and a
non-local interaction is observed. Entanglement is further verified by the way
of the measured violation of a CHSH type Bell's inequality with S-values of
2.54 and 27 standard deviations. Our results will shine a new light into the
understanding on how quantum mechanics works, have possible philosophic
consequences on the one hand and provide an essential element for quantum
information processing on the other hand. Potential applications of our results
are briefly discussed.
