One of the strangest and most counter-intuitive areas in science is quantum mechanics. Even scientists think it is weird. Nobel prize-winning physicist Niels Bohr famously commented that "[i]f quantum mechanics hasn't profoundly shocked you, you haven't understood it yet." Albert Einstein, whose discoveries on the dual packet- and wave-nature of light are key building blocks of quantum science, dismissed it with the even more famous line that "God does not play dice with the universe."
None of that means that it isn't potentially useful. For years, scientists have understood that certain things about quantum mechanics make them good candidates for security tasks. A couple of recent stories suggest that quantum tools may be coming closer to reality.
This Dr. Dobbs Portal posting describes -- in mercifully general terms -- research by the National Institute of Standards and Technology (NIST) on efforts to create quantum key distribution (QKD) systems. Keys are the codes that allow encrypted data to be restored to its original form. Researchers have long sought foolproof ways of distributing the keys.
Quantum approaches may be just what the Ph.D.s ordered. One characteristic of quantum science is that it is impossible to measure things without altering them. The benefit of QKD, therefore, is that bells and whistles will go off if a third party -- a criminal -- tries to read the private key. The story details efforts to build practical QKD systems that are usable with current telecommunications gear and otherwise are efficient enough to make them viable. The Chinese government also is working on QKD systems.
This story at RF Globalnet describes similar research by the European Space Agency. Two photons can become linked, or entangled. A key piece of quantum weirdness is that if a photon that is entangled separates and subsequently interacts with a third photon, the quantum state of its former mate changes. This can be used to guard against efforts to decipher private keys.
The entanglement phenomenon has been known for a long time. The story deals with experiments aimed at finding out whether it works over long distances. The Austrian-German ESA team has demonstrated it over 144 meters (just under 90 miles) and shown that it works through the atmosphere.
This Daily Yomiuri Online piece provides an interesting recap of where quantum cryptography stands. The writer does a good job of explaining QKD in an accessible manner. He differentiates this from entanglement, which he mentions but doesn't describe. He says a team at the Massachusetts Institute of Technology has made enough progress on breaking quantum cryptography to cast doubt on the assumption that it is 100 percent secure. The MIT research is more fully described at Engadget.
It will be a while before quantum cryptography and other quantum mechanics-based security tools can be purchased at Best Buy. But security personnel and organizational decision-makers should be aware of this strange and potentially valuable new approach to security, especially as research picks up.