Quantum Communication
Jul 16, 2011 17:12:40 GMT -5
Post by PrisonerOfHope on Jul 16, 2011 17:12:40 GMT -5
First, here's a brief explanation of what it is:
eve.physics.ox.ac.uk/NewWeb/Research/communication/communication.html
Interestingly, it's being spoken of on the Space Weather site:
SPOOKY COMMUNICATION: "The skies over the Spanish island of La Palma offer many beauties, but on July 4th I witnessed something unusual: a ghostly green laser beam crossing the Milky Way," reports Jan Hattenbach from the Canary Islands. "I have learned that it was part of an experiment in quantum communication." Scroll past the laser for more information:
"Rupert Ursin of the Institute for Quantum Optics and Quantum Information at the Austrian Academy of Sciences explained to me that the laser was part of an inter-island quantum-cryptography experiment," says Hattenbach. "Physicists send entangled UV-photons from the Roque de los Muchachos observatory (ORM) on La Palma to the European Space Agency's Optical Ground Station 144 km away on the island of Tenerife. The goal is to demonstrate the feasibility of quantum communication over very long distances in space--e.g., to the International Space Station or other satellites.
"While the UV photons are invisible to the human eye, the green laser is not: it is used as a tracking laser or a giant laser pointer. It remained visible even in broad twilight - and made a good show together with the milky way, the morning zodiacal light and Jupiter."
Sending coded information via entangled photons? If the idea disturbs you, you're in good company. Einstein himself ridiculed the notion as "spooky action at a distance." Experiments like this one, however, show that it is possible.
eve.physics.ox.ac.uk/NewWeb/Research/communication/communication.html
Interestingly, it's being spoken of on the Space Weather site:
SPOOKY COMMUNICATION: "The skies over the Spanish island of La Palma offer many beauties, but on July 4th I witnessed something unusual: a ghostly green laser beam crossing the Milky Way," reports Jan Hattenbach from the Canary Islands. "I have learned that it was part of an experiment in quantum communication." Scroll past the laser for more information:
"Rupert Ursin of the Institute for Quantum Optics and Quantum Information at the Austrian Academy of Sciences explained to me that the laser was part of an inter-island quantum-cryptography experiment," says Hattenbach. "Physicists send entangled UV-photons from the Roque de los Muchachos observatory (ORM) on La Palma to the European Space Agency's Optical Ground Station 144 km away on the island of Tenerife. The goal is to demonstrate the feasibility of quantum communication over very long distances in space--e.g., to the International Space Station or other satellites.
"While the UV photons are invisible to the human eye, the green laser is not: it is used as a tracking laser or a giant laser pointer. It remained visible even in broad twilight - and made a good show together with the milky way, the morning zodiacal light and Jupiter."
Sending coded information via entangled photons? If the idea disturbs you, you're in good company. Einstein himself ridiculed the notion as "spooky action at a distance." Experiments like this one, however, show that it is possible.
