The trick is to make sure it removes faster than it adds. Horodecki, Héctor Bombín of the Massachusetts Institute of Technology and their colleagues recently devised such a setup, but for geometric reasons it would require higher spatial dimensions. Several other recent papers make do with ordinary space; instead of relying on higher geometry, they thread the system with force fields to tilt the balance toward error removal. But these systems may not be able to perform general computation.
This work suggests that, contrary to conventional wisdom, entanglement can persist in large, warm systems—including living organisms. “This opens the door to the possibility that entanglement could play a role in, or be a resource for, biological systems,” says Mohan Sarovar of the University of California, Berkeley, who recently found that entanglement may aid photosynthesis [see “Chlorophyll Power,” by Michael Moyer; Scientific American, September 2009]. In the magnetism-sensitive molecule that birds may use as compasses, Vedral, Elisabeth Rieper, also at Singapore, and their colleagues discovered that electrons manage to remain entangled 10 to 100 times longer than the standard formulas predict. So although we may not be electrons, living things can still take advantage of their wonderful quantumness.
Note: This article was originally printed with the title, "Easy Go, Easy Come."