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Technology Hardware

Rod Logic Computers and Why We Don't Already Have Them (hackaday.com) 31

szczys writes: Carbon Nanotubes and Graphene breakthroughs pop up in the news often enough for them to be considered buzzwords. Most of the time it's the superconducting properties of graphene that are touted, but molecule-scale structures also hold the promise of building mechanical computing devices that are unimaginably small. The reason we don't have these things yet comes down to the manufacturing process. Building machines out of carbon molecules is commonly called Rod Logic — a topic many know from the seminal novel The Diamond Age. Al Williams discusses how Rod Logic works and highlights some of the places we're already seeing these materials like to help cool LED light bulbs, and to strengthen composites.
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Rod Logic Computers and Why We Don't Already Have Them

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  • No doubt we'll get around to nanoscale rod logic just as soon as we've figured out how to genetically-engineer the mechanisms needed to assemble them. ;)
  • by Anonymous Coward
    What was the point of the article? To tell us that we don't have nanometre scale devices... because we can't manufacture nanometre scale devices yet?
  • "The reason we don't have these things yet comes down to the manufacturing process"

    Gee, that's very interesting. How about giving a summary of it in your post?
  • by Anonymous Coward on Monday October 19, 2015 @06:43PM (#50762023)

    Ok, as a thought experiment "Rod Logic" is neat. As a practical application? We're just going to keep pushing electrons through semi conductors until such time as we can figure out how to do the same thing with photons in, whatever decade that happens. Non solid state computational logic isn't a great idea for a lot of reasons. And while graphene is probably the near(ish) future it's for a reason that the author (and a large portion of the traditional semi conductor industry) miss.

    Graphene is awesome, because it doesn't leak heat and has an electron mobility far higher than silicon. These two combine to bring back something from a decade or more ago, and that's clock speed. It's been "stuck" on the sweet spot of 1-2ghz for years and years and year now as that's where silicon operates best. But graphene, which uninformed articles not withstanding can be made into a semiconductor in quite a few ways, can clock far, far, far higher. Easily over a hundred times higher than silicon in theory.

    How to get it to grow, and arrange itself into traditional nanometer scale wiring with high precision, and do so as a semiconductor, at industrial scales is certainly an open question. But one many, many researchers and companies that don't want to rely on silicon lithography forever seem fairly certain is a question that can be answered. And once it is all this nonsense about Moore's law being the only way to make computers better need not be continued. Who cares about molecule scale transistors if your CPU is clocked at 200+ ghz (or even terahertz, which is theoretically possible...) We don't need ever smaller, and exponentially harder to make transistors. We just need to get back to making them faster. And either graphene, or black phosphorous (a 2d phosphorous allotrope) or something else will certainly get us there.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      Non solid state computational logic isn't a great idea for a lot of reasons.

      Oh? Name three*, besides the obvious problem with manufacture. It's worth noting that once you get to really small sizes the distinction between solid state and moving parts starts to break down.

      *Pardon the snark, but normally when I hear someone use a phrase like 'lots of reasons' it's usually because they have no idea what they're talking about.

    • by radarskiy ( 2874255 ) on Tuesday October 20, 2015 @12:54AM (#50763583)

      "Who cares about molecule scale transistors if your CPU is clocked at 200+ ghz"

      The guy stuck trying to converge a path with 5 cycles of clock skew cares a heck of a lot.

    • by Anonymous Coward on Tuesday October 20, 2015 @05:04AM (#50764115)

      Silicon can reach clock speeds to 100 GHz without an issue, the problem is related to getting 100 GHz on chip scale. At such high speeds the speed of light plays a large role and you simply can't shuffle data around the die fast enough.

      Also graphene cannot be made into a semiconductor without severely affect its mobility. You can have one or the other, but not both yet.

  • I'm also kind of curious how a mechanical logic process, strengthens composites ?

  • If I could make a mechanical calculator at that scale, then I could just as easily make an electronic one, at that scale. The problem is the "manufacturing issues" they talk about are the same challenges that thwart building microelectronics on the same scale. Solve one, you solve the other, and electrons are a LOT smaller than rods, there's very little chance rods will outperform electronic or electro-optical gates of similar scale.

  • mag amps....rod positioning memory post-scram....it was there!
  • Hey guys, you're being trolled.

  • by fragMasterFlash ( 989911 ) on Tuesday October 20, 2015 @12:29AM (#50763513)
    A sage old electrical engineer about laughed me out of the room back '97 when I told him I seriously thought MEMS [wikipedia.org] would be the next big thing. You know what? I think he is still laughing.
  • Our Worker of the Week, and the hero of the Corvair I shuttle mission.

    In (nano) Rod We Trust!

Order and simplification are the first steps toward mastery of a subject -- the actual enemy is the unknown. -- Thomas Mann