Thursday, January 29, 2004
Fermionic Condensate Unveiled
From the free section of Nature online (registration required) Fermions chill out: New form of quantum matter unveiled:
"Jin and her colleagues made the condensate by cooling a gas of about half-a-million potassium atoms to within 50 billionths of a degree above absolute zero, the coldest temperature possible. They used a magnetic field to coax the atoms to stand close together in pairs, although without actually bonding. These atomic pairs bear a good likeness to the electrons that produce superconductivity."
Update: Less experimental detail, but more background provided by this Physics News Update story.
An article entitled Technology Review: Technique Detects Quantum State has a brief summary of research originally published in the November 28, 2003 issue of Physical Review Letters:
"The researchers generated entangled photons using a crystal and a pair of laser beams. They showed that it was possible to detect entanglement using three independent local measurements. The method is particularly useful for determining if entanglement survived the transmission of photons over a fiber optic line."
Monday, January 26, 2004
Prime Obsession: $20 book, free online
This still-in-hardcover book is available for free here: Nat'l Academies Press, Prime Obsession. The only catch, as far as I can[t] see, is that the small fuzzy font can cause eye strain (unless you download each individual page as a .pdf).
Saturday, January 24, 2004
Technology Review: Quantum Dice Debut: "Researchers from the Massachusetts Institute of Technology and the National Atomic Energy Commission in Argentina have shown that short sequences of random operations—randomly shifting laser pulses or magnetic fields—acting on a string of quantum bits can, in effect, generate random configurations of qubits."
It's been long known how to randomize qubit states, so this new method must be much more time efficient to be of note...unfortunately this article does not mention the new algorithm's complexity. Anyone with a subscription to Science care to fill us in?
Thursday, January 22, 2004
Peter Shor's Quantum Computation Course
Peter Shor's been lecturing at MIT, and here are student-scribed notes for course number 18.435 / 2.111.
Atom Cloud QC
"Researchers from Brussels Free University in Belgium (ULB) and the Niels Bohr Institute in Denmark have shown that the collective spin of clouds of atoms can be used to compute." Technology Review: Atoms Make Quantum Coprocessor
Thursday, January 15, 2004
Quantum Computing Debate
A lively discussion on the feasiblity of quantum computation, from the FaN conference in Santa Fe in June 2003. "We’re not building this so that we can run Microsoft Office on it. [Audience laughter]" - Julio Gea-Banacloche
Supersolid Experimentally Discovered
"In the 15 January 2004 issue of the journal Nature, two physicists from Penn State University will announce their discovery of a new phase of matter, a "supersolid" form of helium-4 with the extraordinary frictionless-flow properties of a superfluid."
The summary is from Eurekalert.
Wednesday, January 14, 2004
"The Qubib project consists into [sic] a bibliography database for the field of quantum information."
Tuesday, January 13, 2004
Nobel Prize Winner's New Quantum Computing Book
"Kluwer Academic Publishers today announced the anticipated release of 2003 Nobel Prize winner Dr. Anthony Leggett's new book Quantum Computing and Quantum Bits in Mesoscopic Systems....On the theoretical side, Quantum Computing and Quantum Bits in Mesoscopic Systems provides models of the various mesostructures and of their response to external control signals, addressing the thorny problem of minimizing decoherence."
Sunday, January 11, 2004
Computational Complexity Blog
Frequently updated, and all about algorithms: Lance Fortnow's Computational Complexity Web Log
Friday, January 09, 2004
Peering One Year Into the Future
The Guardian Unlimited has an article entitled "10 things we'll know by this time next year." They also mention 10 things we won't know by next year, which includes "Quantum computers...There's progress every year but no one has a clue when it will become a reality or what it would look like if it did." On the positive side they predict high quantity quantum dot production, and neutrino mass successfully weighed.
Speaking of neutrinos, what kind of quantum computing register particle would they make? They would likely be extremely expensive to manipulate since they react so weakly with their environment. But on the plus side, they would be virtually free from decoherence effects.
Monday, January 05, 2004
Check out the weblog of quantum computing professor Michael Nielson. He is author of this book on quantum computation.
Saturday, January 03, 2004
Unexpected Quark Spin
I've yet to hear of any quark-based quantum computers, but if there ever was one, this could be a setback of sorts: "In neutrons and protons, quarks take wrong turns" Science News Online, Jan. 3, 2004