Quantum Weirdness: Two Times Zero Doesn't Always Equal Zero

[n2doc]

By Mark Anderson
First Published August 2008

In a surprising discovery released this week, physicists have announced that two times zero does not always equal zero.

The new theoretical research examines transmissions of individual quantum states, such as sending a single photon down a fiber-optic cable and reading off its polarization on the far end. Rather than shipping the lone photon down a clean and undisturbed line, the researchers considered sending information down two lines that contained too much static to transmit anything reliably. When the lines were examined alone, each noisy channel proved as useless as a dead telephone jack. However, the researchers calculated that someone on the far end of two noisy channels used together could in fact extract actual information from the individually worthless lines.

The finding, while still purely theoretical, nevertheless promises to open up new methods of both strengthening quantum cryptography and assisting in the elusive quest to build a quantum computer.

The counterintuitive nature of the announcement stems from the peculiar kind of information being studied. Unlike the classical bit, which is simply either zero or one, the quantum bit can exist in an infinite number of intermediate states between zero and one. It also contains a feature that befuddled even Albert Einstein: measurements of one quantum bit affect the information carried by another quantum bit with which it has previously been in contact. (Most troubling to the legendary physicist was the fact that two “entangled” quantum bits could theoretically lie on opposite sides of the universe from each other—and yet a measurement performed on one would still instantaneously affect its twin.)

The new finding, emerging from IBM’s Thomas J. Watson Research Center, in Yorktown Heights, N.Y., and Los Alamos National Laboratory, in New Mexico, compounds paradox upon paradox. In essence, the spooky form of information whose behavior no one completely understands—but which has nevertheless been rigorously observed in the lab—now seems capable of appearing on the distant side of a supposedly impassable divide.

“This paper raises more questions than it answers,” admitted coauthor Graeme Smith of IBM, whose work appears in Thursday’s online edition of Science Express and will appear in a forthcoming issue of the journal Science. “One interpretation seems to be that there are different kinds of communication—or different kinds of quantum information that these two channels might be transmitting.”


more:

http://www.spectrum.ieee.org/aug08/6609

[coffeenap]

1. Thanks for this--a whole list of my kid and his friends will love it!

They are math and/or physics geeks along with history, languages, computers, you name it! Can't wait to overhear their debate!

[FredStembottom]

2. Reminds me of how I transfer 78 rpm records to digital. No, really.

78's are scratchy. Really scratchy. Even ones in excellent condition have LOTS of inherent noise. The noise can be louder than the music at times.

But wanting to make permanent transfers of my 78's collection, I experimented quite a while and found something like the above article. Bear with me:

78's are a monophonic format. One channel. When a 78 is played, all the sound comes out of one point in the sound field. You are supposed to play them with a monophonic cartridge on your turntable (that also has a larger needle (or stylus) that fits the larger grooves better).

I soon discovered that playing a 78 with a stereo cartridge still produced mono music (stuck in the center of the "stereo" sound field) but stereo scratches and noise (the noise seems to float outside and around the mono music at the center of the sound field). And the smaller needle increased the noise quite a bit because it doesn't fit the groove quite right.

I guessed - and found I was right - that taking that stereo signal (music and noise) into a mixer and mixing it all back together into an all-mono signal left the wanted music untouched but reduced the unwanted noise quite a lot; to below what you get with a genuine 78's cartridge installed on your turntable.

The noise is naturally 180 degrees out of phase with itself. When sent through in stereo - combining the signals self-cancels a lot of the noise.

To me, this all has a similar feeling to the experiment above. To what significance? I dunno........

:shrug:

[wtmusic]

3. Fascinating.

Could this be related in some bizarre way to the "2-slit experiment"?

http://en.wikipedia.org/wiki/Double-slit_experiment

[screembloodymurder]

4. Shit, and I thought the new math was hard to understand.

The new physics has me head spinning. 2 X 0 = ?

[FiveGoodMen]

5. Terrible headline

It's not two times zero at all.

It's comparing two sets of badly damaged data to try and extract the original info.

Same absolute crap science reporting as always.

[melody]

6. Maybe because there are zeros with differing values? :)

Not all zeros are created.