Nonlinearity without superluminality (4 pages)

Vasily R. Shaginyan, D. Sokolovski, ALFRED Z. MSEZANE

J. Miguel Hickmann, R. Y. Chiao

G. C. Ghirardi

Li Zhan, Kai Qian, Liang Zhang +3 more

We proposed and demonstrated the propagation of slow/fast light in erbium-doped fiber through gain cross modulation. We observed the ultraslow light with a group velocity of 6.1×10-3 c and the superluminal propagation with a negative group velocity of -5.1 ×10-4c. (2 pages)

R. Y. Chiao, Eric L. Bolda, Jason L. Bowie +2 more

Shan Gao

A possible mechanism of nonlinear quantum evolution is introduced and its implications for quantum communication are investigated. First, it is argued that an appropriate combination of wavefunction collapse and the consciousness of observer may permit the observer to distinguish nonorthogonal quantum states in principle, and thus consciousness will introduce certain nonlinearity into quantum dynamics. Next, it is shown that the distinguishability of nonorthogonal states can be used to achieve quantum superluminal communication, by which information can be transmitted nonlocally and faster than the speed of light. Finally, the issue of apparent incompatibility between superluminal communication and special relativity is briefly addressed.