Ron Garret, formerly of JPL and Google and "the most referenced computer science researcher in all of NASA", has an interesting take on quantum mechanics he dubs "zero-worlds", which he presents in an hour-long
Google Tech Talk (meat starts around 42 minutes) as well as slightly older
paper. He also got into a bit of further debate
here.
[more inside]
posted by crayz
on Mar 23, 2013 -
26 comments
The Nature of Computation -
Intellects Vast and Warm and Sympathetic: "I hand you a network or graph, and ask whether there is a path through the network that crosses each edge exactly once, returning to its starting point. (That is, I ask whether there is a 'Eulerian' cycle.) Then I hand you another network, and ask whether there is a path which visits each node exactly once. (That is, I ask whether there is a 'Hamiltonian' cycle.) How hard is it to answer me?" (
via)
[more inside]
posted by kliuless
on Dec 1, 2012 -
19 comments
The 2012 Nobel Prize in Physics has
been awarded to Serge Haroche (France) and David Wineland (US) for discovering ways to measure and manipulate quantum particles, a discovery which
many are suggesting may soon allow us to build computers with virtually limitless capabilities. The Nobel press release provides a layman friendly
PDF summary of the research and its potential applications, as well as a less layman friendly PDF with additional
scientific background information. The press release cites two older Scientific American articles for further reading, and the magazine has made these articles available to read free online for the next 30 days:
Monroe, C. R. and Wineland, D. J. (2008) Quantum Computing with Ions, Scientific American, August.Yam, P. (1997) Bringing Schrödinger’s Cat to Life, Scientific American, June.
posted by dgaicun
on Oct 15, 2012 -
51 comments
Morton and Vicary on the Categorified Heisenberg Algebra - "In quantum mechanics, position times momentum does not equal momentum times position! This sounds weird, but it's connected to a very simple fact. Suppose you have a box with some balls in it, and you have the magical ability to create and annihilate balls. Then there's one more way to create a ball and then annihilate one, than to annihilate one and then create one. Huh? Yes: if there are, say, 3 balls in the box to start with, there are 4 balls you can choose to annihilate after you've created one but only 3 before you create one..."
[more inside]
posted by kliuless
on Jul 21, 2012 -
78 comments
"Using four photons, we can actively delay the choice of measurement on two of the photons into the time-like future of the registration of the other two photons. This effectively projects the two already registered photons onto one of two mutually exclusive quantum states in which the photons are either entangled (quantum correlations) or separable (classical correlations). This can also be viewed as ‘quantum steering into the past’." (
arXiv,
Nature Physics,
Ars Technica)
posted by jeffburdges
on Apr 25, 2012 -
80 comments
... and there is no dark matter/energy! Dr. Philip
Mannheim has succeeded in developing a cosmological and quantum field theoretic consistent PT symmetric theory that contains no kind of dark matter and dark energy.
Space is flat in the absence of matter, and even the largest galactic rotation curves are predicted. Perhaps most interestingly, it also handles the cosmological constant and zero-point energy 'problems' simultaneously! (This is the final paper in a
long list of publications, but it makes the case such that it's importance is immediately recognized. I leave it to the experts to recognize it's true beauty.) All hail the internets!
posted by quanta and qualia
on Apr 21, 2011 -
210 comments
Gravity from Quantum Information At the heart of their idea is the tricky question of what happens to information when it enters a black hole. Physicists have puzzled over this for decades with little consensus. But one thing they agree on is Landauer's principle: that erasing a bit of quantum information always increases the entropy of the Universe by a certain small amount and requires a specific amount of energy. (via
mr)
posted by kliuless
on Apr 1, 2010 -
33 comments
Quantum processes involved in photosynthesis? "[A]lgae and bacteria may have been performing quantum calculations at life-friendly temperatures for billions of years. The evidence comes from a study of
how energy travels across the light-harvesting molecules involved in photosynthesis. The work has culminated this week in the extraordinary announcement that these molecules in a marine alga may exploit quantum processes at room temperature to transfer energy without loss. Physicists had
previously ruled out quantum processes, arguing that they could not persist for long enough at such temperatures to achieve anything useful." (
via mr)
posted by kliuless
on Feb 10, 2010 -
43 comments
The Crossing is a new FPS game where single-player and multiplayer modes meld in one. At any point, any Non-Player-Character might not be an NPC at all, but another Player. It is likely that, as in a game of tag, players will just take turns to be "it" like Agents in the Matrix, but... wouldn't it be great if we could all be "it" at the same time?
Quantum Gaming might just be the way to model such a swarm of gamers.
[more inside]
posted by kandinski
on Sep 23, 2007 -
30 comments
Quantum Encryption Scientists have created an unbreakable cypher through the use of quantum physics, where a photon is observed and used as the basis for an encryption key. "Uncertainty is the principle we exploit. It's impossible to find the key, because the photon can be measured once and only once. An eavesdropper can't measure it, and so can't get the key." Props to Heisenberg!
posted by PreacherTom
on Nov 9, 2006 -
49 comments
Teleportation Breakthrough. Until now scientists have teleported similar objects such as light or single atoms over short distances from one spot to another in a split second.
But Professor Eugene Polzik and his team at the Niels Bohr Institute at Copenhagen University in Denmark have made a breakthrough by using both light and matter.
A more technical explanation.
posted by empath
on Oct 5, 2006 -
67 comments
Before the Big Bang -
way,
way out of my depth, but I thought this comment was intriguing: "The paper as published, along with a longer follow up paper, looks to my untrained eye a nearly complete quantum gravitation theory, which is an exciting prospect in itself. However, as with all physical theories, we will await for experimental support before popping the cork." Here's some more on
loop quantum gravity,
spin networks,
the big bang and
ekpyrosis.
posted by kliuless
on Apr 16, 2006 -
18 comments
Boundless energy or bad math? Randell Mills thinks he has the solution to our energy problems. In his company's patented
process,
"energy is released as the electrons of atomic hydrogen are induced to undergo transitions to lower energy levels producing plasma, light, and novel hydrogen compounds." It also implies that quantum mechanics is wrong.
posted by Espoo2
on Nov 5, 2005 -
73 comments
A bold paper published in the August issue of Foundations of Physics Letters seems set to change the way we think about the nature of time and its relationship to motion and classical and quantum mechanics. The work also appears to provide solutions to
Zeno's paradoxes. (Via
Kurzweilai.net. More inside...)
posted by Pinwheel
on Aug 1, 2003 -
41 comments
