IBM Claims Spintronics Memory Breakthrough

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IBM Claims Spintronics Memory Breakthrough

Posted by timothy on Monday August 13, 2012 @12:08AM from the dance-electrons-dance dept.

CWmike writes with this excerpt from ComputerWorld: "In a paper set to be published this week in the scientific journal Nature, IBM researchers are claiming a huge breakthrough in spintronics, a technology that could significantly boost capacity and lower power use of memory and storage devices. Spintronics, short for 'spin transport electronics,' uses the natural spin of electrons within a magnetic field in combination with a read/write head to lay down and read back bits of data on semiconductor material. By changing an electron's axis in an up or down orientation — all relative to the space in which it exists — physicists are able to have it represent bits of data. For example, an electron on an upward axis is a one; and an electron on a downward axis is a zero. Spintronics has long faced an intrinsic problem because electrons have only held an 'up or down' orientation for 100 picoseconds. A picosecond is one trillionth of a second [one thousandth of a nanosecond.] One hundred picoseconds is not enough time for a compute cycle, so transistors cannot complete a compute function and data storage is not persistent. In the study published in Nature, IBM Research and the Solid State Physics Laboratory at ETH Zurich announced they had found a way to synchronize electrons, which could extend their spin lifetime by 30 times to 1.1 nanoseconds, the time it takes for a 1 GHz processor to cycle."

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Was it really necessary... by Joce640k · 2012-08-13 00:16 · Score: 2, Interesting

Was it really necessary to explain the SI unit 'pico' on Slashdot...?

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1. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 00:20 · Score: 5, Insightful
  
  Sure, not everyone one who comes to /. is a long time geek. We all start somewhere.
2. Re:Was it really necessary... by inasity_rules · 2012-08-13 00:23 · Score: 3, Insightful
  
  Yes, this is an america-centric site, as we are often reminded, and you guys don't like SI units... :P
  Queue the Metric/Imperial Wars:
  In all seriousness, they could have just given the frequency and we'd have been fine. That refresh rate is very doable with a dedicated controller.
  
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3. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 00:48 · Score: 1
  
  ...And if you're going to explain a SI unit in slashdot, you could at least use proper units.
  For reference there are 1.2 picoseconds in an attofortnight.
4. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 00:50 · Score: 1
  
  Pico is a prefix, not a unit.
5. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 01:13 · Score: 2, Interesting
  
  Was it really necessary for you to type 'Was it really necessary' twice? You could have just put an ellipse before the second part, especially since you ended the subject with an ellipse.
  It's an ellipsis, pal. You spent too much time in Mathematics courses and not enough in writing.
6. Re:Was it really necessary... by petteyg359 · 2012-08-13 01:30 · Score: 3, Funny
  
  I don't see any cone intersections in his text. Perhaps you meant ellipsis...
7. Re:Was it really necessary... by wbr1 · 2012-08-13 01:31 · Score: 1
  
  Was it really necessary to explain 0 and 1 as bits?
  
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8. Re:Was it really necessary... by timeOday · 2012-08-13 01:45 · Score: 4, Funny
  
  Put another way, if 100 slashdotters had to answer the question "pico = 10^x", does anybody really think we'd all get it right?
9. Re:Was it really necessary... by ceoyoyo · 2012-08-13 01:57 · Score: 2
  
  "Picosecond," which is what was used in the summary, is a metric unit.
10. Re:Was it really necessary... by Jade_Wayfarer · 2012-08-13 02:05 · Score: 5, Funny
  
  1 hectoslashdotter cannot be wrong!
  
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11. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 02:39 · Score: 3, Insightful
  
  I absolutely hate posts that put part of the reply into the subject line, and you should burn for encouraging it.
12. Re:Was it really necessary... by Anonymous Coward · 2012-08-13 02:53 · Score: 2, Funny
  
  I don't see any cone intersections in his text. Perhaps you meant ellipsis...
  I do. Indeed, I see four of them in your comment.
13. Re:Was it really necessary... by cellocgw · 2012-08-13 04:39 · Score: 4, Funny
  
  Queue the Metric/Imperial Wars:
  So "Queue" is the metric equivalent of "Cue" ?
  
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14. Re:Was it really necessary... by inasity_rules · 2012-08-13 05:04 · Score: 1
  
  It is a queue. Well maybe not you could possibly have both wars at once. Anyway, just a brainfart.
  
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15. Re:Was it really necessary... by Spy+Handler · 2012-08-13 08:22 · Score: 1
  
  no, it was not necessary. If you're not a geek and don't know what pico means, look it up. Does CNBC explain what an IPO is what P/E ratio means is in every article?
16. Re:Was it really necessary... by Artifakt · 2012-08-13 09:17 · Score: 1
  
  The better question might be, does CNBC explain what an Initial Public Offering or Profit/Earnings ratio is more or less often than does the Wall Street Journal, the Motley Fool, or Morningstar? If CNBC is actually professional, then every time someone writes an article that is likely to attract a lot of less informed readers, they actually go to extra lengths to explain Three Letter Acronyms and such in those particular articles. By that metric, this Slashdot summary is relatively unlikely to attract people unconversant with terms such as pico, and there's probably less need to spell everything out than in a summary about, say, "Why Windows 8 is dropping the Start button", or similar. That supports your take on the matter.
  My own instinct in writing, though, is to err on the side of caution, as I've done here. I know of some pros who swear by always explaining any technical term the first time it is used in a story. I think of it as going to extra trouble for the occasional reader of genuinely good will who may be young, inexperienced, trying to follow something that isn't in his or her native tongue, or otherwise having a few extra obstacles, through no fault of his or her own. Yes, that's probably coddling some lazy readers too, but they aren't why I would do it.
  
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17. Re:Was it really necessary... by lengau · 2012-08-13 09:46 · Score: 1
  
  It's still part of the metric system.
  
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18. Re:Was it really necessary... by kermidge · 2012-08-14 01:17 · Score: 1
  
  Well done. I was taught long ago that the first use of an abbreviation, acronym, or technical term was to be spelled out and a concise definition given if appropriate.
  As it happens, I knew what "pico" was; the problem I have is trying to visualize the very small and very large. I suppose that's why I appreciate things such as furlongs per fortnight.
19. Re:Was it really necessary... by petteyg359 · 2012-08-14 02:36 · Score: 1
  
  Be careful with that. You don't want Q to start introducing chaos...
RRDRAM? by jeffb+(2.718) · 2012-08-13 00:23 · Score: 2, Funny

That's some really, really dynamic RAM. Don't skip a refresh cycle.
1. Re:RRDRAM? by dave420 · 2012-08-13 04:05 · Score: 2
  
  Read about it, and you'll see exactly how it saves power. It's a better use of your time than writing either lazy pleas for education or rhetorical nonsense.
2. Re:RRDRAM? by sapgau · 2012-08-13 06:07 · Score: 1
  
  Wow, snarky. It was easier for you to explain but you decided to take the easiest posture every pseudo-geek takes.
  I bet the reason you do it is because you don't know either so to show who's boss you act like a tough guy, big boy.
3. Re:RRDRAM? by bluefoxlucid · 2012-08-13 06:16 · Score: 2
  
  No, no I won't. See, the trick with semiconductor technologies is they're slow or they're hungry. If they're at GHz, they're power-hungry; if they're light on power, they're slow. Look at ARM. 0.1W of peak power at 600MHz. At 1200MHz, 1W of peak power. That's 10 times as much power consumption and it's a very light weight chip. DDR and QDR RAM uses an internal buffer and runs at high external speeds, but internally it's running at 100MHz or so instead of 400MHz. DDR3 particularly transfers on the up and down clock of a quadrupled clock, so twice per cycle you get a load of 4 chunks of data pulled down (8x speed). Why? Because running at a straight 1600MHz instead of 200MHz and sending a pulse on clock up and clock down would be lunacy, and the chip would overheat and suck tons and tons of electricity.
  This memory actually has to be refreshed at 1000MHz internal clock. DDR3 fastest? 266 2/3 internal clock. At 1000MHz it has to read, then write back to refresh. That's got to be done across the entire array (each storage word needs its own refresh circuit, or you need one hell of a fast refresh circuit scanning memory). That's a hell of a lot of independent operations happening in parallel.
  
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4. Re:RRDRAM? by DigiShaman · 2012-08-13 13:27 · Score: 1
  
  So if I'm understanding this correctly, spintronic based RAM would have to be registered memory.
  
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5. Re:RRDRAM? by bluefoxlucid · 2012-08-14 03:18 · Score: 1
  
  It's not so much that. DDR has a buffer inside because it's operating at 200MHz instead of 800; internally it can, say, run 4 fetches in parallel and load a 1 word buffer, while the external clock then runs at 4 times the speed and drains that buffer. Registered RAM is something else.
  The problem here is that DDR runs at 200MHz internally because running silicone at 800MHz leaks a lot of power and thus consumes a ton of power and gets very hot.
  Internally you'd need DDR running at 1GHz for this at the very least. That's like 100 times as much power and then some. You'd need a solid state "read-write head" to read each byte, then rewrite it back for writeback refresh. It would get extremely hot and eat power like your mom eats load.
  
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Likely not by doublebackslash · 2012-08-13 00:23 · Score: 4, Insightful

Likely not, or not like they claim. Stories like this remind me of Maxwell's Demon. It seems to violate the rules, allows for unlimited energy! Except until you realize that the demon can't be run for free. They claim the breakthrough in stability of the spin states and neglect the cost in space and energy in everything else around it.
Stop this sensationalism! Give me some science on it and tell me some more details. How do they generate electrons with a single spin? How about a blurb about spintronics already being used in modern hard drive read heads? Cut the nonsense and tittilating lies about promises of the future and tell us the details.
Geez

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1. Re:Likely not by Anonymous Coward · 2012-08-13 00:35 · Score: 1
  
  > How do they generate electrons with a single spin?
  Apply a magnetic field.
  > How about a blurb about spintronics already being used in modern hard drive read heads?
  The article is about semiconductor RAM, not ferromagnetic hard drives and not about their read heads.
  > Cut the nonsense and tittilating lies about promises of the future and tell us the details.
  DITO
2. Re:Likely not by GuldKalle · 2012-08-13 00:44 · Score: 3, Insightful
  
  Just because the product is not in the shops by tomorrow doesn't mean it's sensationalism.
  What we have just witnessed is science. What follows is a lot of optimizations, experiments, cost/benefit analyses, prototyping etc, aka engineering.
  It is a breakthrough because the engineers have gotten a a new tool in their toolbox.
  It is not sensationalism because there are not a extravagant claims.
  Geez
  
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3. Re:Likely not by doublebackslash · 2012-08-13 01:05 · Score: 1, Insightful
  
  There is an extravagant claim.
  
  IBM researchers are claiming a huge breakthrough in spintronics, a technology that could significantly boost capacity and lower power use of memory and storage devices
  But that isn't really even the worst part. It might be true, it might come to pass. Fine, fine. Don't gush about it for half the article, or if they insist on gushing then at least lay out the chllenges and technical details needed to get there.
  Sorry I seemed as though I don't appreciate their work. I do. I just want more than a friggin advertisment for an article.
  
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4. Re:Likely not by vlm · 2012-08-13 01:14 · Score: 4, Insightful
  
  It is not sensationalism because there are not a extravagant claims.
  Its toward the end of the summary, where the only thing preventing spintronic deployment is the refresh rate was immensely way too high, now its merely too high.
  As you listed, there's a lot more work to be done if this is ever deployable. Just lowering the refresh rate from laughable to ridiculous is not enough.
  
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5. Re:Likely not by docmordin · 2012-08-13 01:53 · Score: 5, Informative
  
  Give me some science on it and tell me some more details.
  Since they didn't give a link to it, here's the citation for the paper in question: M. P. Walser, et al., "Direct mapping of the formation of a persistent spin helix", Nature Phys., 2012 (accepted, in press). You can read all of the wonderfully gritty, and hard-to-parse, details in that paper.
  If you want to learn more about the science behind spintronics, feel free to peruse:
  M. Johnson and R. H. Silsbee, "Interfacial charge-spin coupling: Injection and detection of spin magnetization in metals", Phys. Rev. Lett. 55: 1790-1793, 1985
  M. N. Baibich, et al., "Giant magnetoresistance of (001)Fe/(001)Cr magnetic superlattices", Phys. Rev. Lett. 61: 2472-2475, 1988
  G. Binasch, et al., "Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange", Phys. Rev. B 29: 4828, 1989
  S. Datta and B. Das, "Electronic analog of the electrooptic modulator", Appl. Phys. Lett. 56: 665-667, 1990
  J. Kikkawa and D. Awschalom, "Resonant spin amplification in n-type GaAs", Phys. Rev. Lett. 80: 4313, 1998
  B. T. Jonker, et al., "Robust electrical spin injection into a semiconductor heterostructure", Phys. Rev. B 62: 8180-8183, 2000
  A. T. Hanbicki, et al., "Efficient electrical spin injection from a magnetic metal/tunnel barrier contact into a semiconductor", Appl. Phys. Lett. 80: 1240, 2002
  S. van Dijken, et al., "Room temperature operation of a high output current magnetic tunnel transistor", Appl. Phys. Lett. 80: 3364-3366, 2002
  X. Jiang, et al., "Optical detection of hot-electron spin injection into GaAs from a magnetic tunnel transistor source", Phys. Rev. Lett. 90: 256603, 2003
  J. Schliemann, et al., "Nonballistic spin-field-effect transistor", Phys. Rev. Lett. 90: 146801, 2003
  B. A. Bernevig, et al., "Exact SU(2) symmetry and persistent spin helix in a spin-orbit coupled system", Phys. Rev. Lett. 97: 236601: 2006
  X. Lou, et al., "Electrical detection of spin transport in lateral ferromagnet–semiconductor devices", Nature Phys. 3: 197-202, 2007
  M. Holub, et al., "Electrical spin injection and threshold reduction in a semiconductor laser", Phys. Rev. Lett. 98: 146603, 2007
  I. Appelbaum, et al., "Electronic measurement and control of spin transport in silicon", Nature 447: 295-298, 2007
  M. Duckheim and D. Loss, "Resonant spin polarization and spin current in a two-dimensional electron gas", Phys. Rev. B 75: 201305, 2007
  B. Behin-Aein, et al., "Proposal for an all-spin logic device with built-in memory", Nature Nano. 5: 266-270, 2010
  J. Wunderlich, et al., "Spin Hall effect transistor", Science 330: 1801-1804, 2010
  
  How about a blurb about spintronics already being used in modern hard drive read heads?
  I can do better than a blurb, I can provide you with references to the underlying science:
  M. Julliere, "Tunneling between ferromagnetic films", Phys. Lett. 54: 225-226, 1975
  J. S. Moodera, et al. "Large magnetoresistance at room temperature in ferromagnetic thin film tunnel junctions", Phys. Rev. Lett. 74: 3273-3276
  W. H. Butler, et al., "Spin-dependent tunneling conductance of Fe/MgO/Fe sandwiches", Phys. Rev. B. 63: 054416, 2001
  J. Mathon and A. Umerski, "Theory of tunneling magnetoresistance of an epitaxial Fe/MgO/Fe (001) junction", Phys. Rev. B. 63: 220403, 2001
  M. Bowen, et al., "Large magnetoresistance in Fe/MgO/FeCo(001) epitaxial tunnel junctions on GaAs(001)", Appl. Phys. Lett. 79: 1655, 2001
  S. Yuasa, et al., "Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions", Nature Mater. 3: 868-871, 2004
  S. S. P. Parkin, et al., "Giant tunnelling magnetoresistance at room temperature with MgO (100) tunnel barriers" Nature Mater. 3: 862-867, 2004
  S. Ikeda, et al., "Tunnel magnetoresistance of 604% at 300 K by suppression of Ta diffusion in CoFeB/MgO/CoFeB pseudo-spin-valves annealed at high temperature", Appl. Phys. Lett. 93: 082508, 2008
6. Re:Likely not by Frequency+Domain · 2012-08-13 02:10 · Score: 2
  
  Just because the product is not in the shops by tomorrow doesn't mean it's sensationalism.
  True, but I'm still waiting for my flying car.
7. Re:Likely not by Anonymous Coward · 2012-08-13 02:45 · Score: 1
  
  I just want more than a friggin advertisment for an article.
  There isn't an existing product or even one in the forseeable future, so what exactly do you think they are advertising?
8. Re:Likely not by jimbolauski · 2012-08-13 06:45 · Score: 1
  
  I just want more than a friggin advertisment for an article.
  There isn't an existing product or even one in the forseeable future, so what exactly do you think they are advertising?
  Funding?
  
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Eek! by gaelfx · 2012-08-13 00:34 · Score: 2, Interesting

Spintronics...uses the natural spin of electrons within a magnetic field in combination with a read/write head to lay down and read back bits of data on semiconductor material.
I'm wondering if this will fail the same way HDDs do when the head falls? Whenever I see something about read/write heads, I get flashblacks to all the clicks-of-death I've heard over the years, and it always makes me wince a little.
I'll admit it, I don't entirely understand what they're talking about here, but it seems a little scant on details such as whether or not this uses readily available (cheap) materials or uses some rare elements that are possibly put to better use elsewhere. I'm sure many will disagree with me and point out cases where I'm wrong, but I'm personally not all that concerned about having more storage, I've got more than I know what to do with at the moment. What I would rather see is some technology that is more easily recyclable.
1. Re:Eek! by Lord+Lode · 2012-08-13 00:42 · Score: 2
  
  If the read/write head fails, it will make a really really terrible scratching sound against the spinning electron!
etch a sketch? by slashmydots · 2012-08-13 00:57 · Score: 1, Funny

If they're relying on the simple rotation of a very tiny particle, couldn't I then significantly erase parts of my SSD by simply shaking it? In other words, erase it like an etch a sketch? :-P I mean how hard I can shake it compared to the mass and energy of a tiny spinning particle, it could start spinning a different way, right? That and ionizing radiation in any tiny dose would blow apart all your data. Get read for an SSD and RAM sticks cased in lead.
1. Re:etch a sketch? by Theophany · 2012-08-13 01:26 · Score: 1
  
  This is a troll, right?
2. Re:etch a sketch? by vlm · 2012-08-13 01:34 · Score: 3, Informative
  
  I mean how hard I can shake it compared to the mass and energy of a tiny spinning particle, it could start spinning a different way, right?
  LOL you wish. The story of chemistry and physics would be a lot different if that were true for protons. I've fooled around with proton magnetometers and NMR machines in chemistry lab and its not so simple to align proton spins. In fact its really freaking hard and energy intensive to align particle spins in general, not just proton spins. This would make an awesome basis for a hard sci-fi story, however. Someone please write a story about a steampunk NMR machine, so I can buy it. I think a Nikola Tesla who invented a steampunk NMR machine in 1870 would be much more interesting than yet another "vampire Tesla". My brain is feeling especially warped today and I'd also like to request a pre-quel involving a steampunk fourier transform infra red spectroscopy analyzer. I would have to think for a minute if there's any technical reason why Fourier himself couldn't have built a FTIR in his era. Hmm glowing charcoal as a IR source, and an early thermometer and lens arrangement as a ghetto IR bolometer, feeding reams of measurement data to hundreds of human clerks making calculations for years to generate each IR spectra, plus or minus an analytical engine or two... Hell a Beowulf cluster of analytical engines...
  As for aligning electron spins like this article its still a huge PITA but the electromagnetic world depends on it. I can't think of any ferromagnetic material that can be (de)magnetized by waving it around... hammer blow level impact will realign the domains but just shakin it isn't going to do it. The reason why can be found on the wikipedia article for coercivity where basically the stuff you make recording media out of doesn't want to demagnetize without a serious fight.
  
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3. Re:etch a sketch? by Gaygirlie · 2012-08-13 02:22 · Score: 1
  
  I'm not a phycisist and I actually know very little of physics even in general, but, well, if it was that easy to alter the state of an electron through simple G-forces then none of the devices we make would be possible. Even a simple car tire is subjected to thousands of times stronger forces than you can generate with nothing but your arms, let alone modern fighter jets and space rockets. Basically, if you wanted to alter the state of electrons like that you would have to shake it so fast your whole body would've burst into flames long before you reach the needed speed just from nothing more than friction. I would definitely love to see you do that, would make a helluva show. Please do inform us when you do that!
4. Re:etch a sketch? by bluefoxlucid · 2012-08-13 02:39 · Score: 1
  
  The entire plot of The Gap Cycle is based on SOD-CMOS chips. It's true. When you get to the last book you'll look back at it all and be like ... holy shit, it is!
  The. ENTIRE. Plot. All of it. Some of the most significant back story (explaining parts of the story BEFORE the story started) requires a thorough explanation of how SOD-CMOS works, and most of the actual plot wouldn't have occurred without that back story.
  
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5. Re:etch a sketch? by tibit · 2012-08-13 03:19 · Score: 1
  
  One can do Earth-field NMR with "RF" at 2kHz (audio frequencies!), see for example Magritek's Terranova-MRI.
  
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6. Re:etch a sketch? by jbengt · 2012-08-13 06:08 · Score: 1
  
  If they're relying on the simple rotation of a very tiny particle, couldn't I then significantly erase parts of my SSD by simply shaking it?
  Ah, so you think that an electron's spin is the same as a macroscopic physical spinning, like a top or a bicycle wheel.
  It's not - at least not as far as we will be able to tell. It's more of an analogy that helps explain/confuse the quantum electric/magnetic properties of the electron with larger scale, more directly observable physics.
Re:Not a breakthrough by sjwt · 2012-08-13 01:49 · Score: 1

Besides, why do all that effort getting the spin to last 30 times longer.. Take the short rout and work on a 30ghz processor! Problem solved!

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Re:I prefer to call it... by Sulphur · 2012-08-13 02:11 · Score: 1

I think a better name would be Super Mega Ultra Golem RAM. (in other words, SMUGRAM) ... that was terrible. I couldn't think of a word for G so I just put Golem.
I'm going to go cry in the stationary cupboard now. I'm sorry.
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Math is hard by PTBarnum · 2012-08-13 03:25 · Score: 3, Interesting

Since when does 100 picoseconds * 30 = 1.1 nanoseconds?
1. Re:Math is hard by DragonWriter · 2012-08-13 05:11 · Score: 2
  
  Since when does 100 picoseconds * 30 = 1.1 nanoseconds?
  The article said it increased the duration by 30 times, which is not the same thing as to 30 times its starting value.
  So you should be asking "Since when does 100 picoseconds * 31 = 1.1 nanoseconds?"
Re:It's "cue", you imbecile by schitso · 2012-08-13 04:23 · Score: 2

Maybe they meant to add that particular war to the war queue?
They used a... by tanveer1979 · 2012-08-13 04:41 · Score: 1

Pentium

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Re:I prefer to call it... by deek · 2012-08-13 13:07 · Score: 1

I couldn't think of a word for G
Gnarly?
Spintronics makes me dizzy by jelle · 2012-08-13 13:51 · Score: 1

See subject.

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