Comment by vitally3643

1 day ago

Yes, and we're already there. We've been there for quite a while, in fact.

Once you make the gate of a transistor small/thin enough, quantum effects take over. Electrons will randomly teleport into and through the gate causing the transistor to conduct when it shouldn't. I don't have numbers to hand, but it's on the order of a few atoms wide. There's really nothing that can be done about it either, as far as we know. Electrons just aren't physical objects at this scale, you can't simply exclude them from any given volume of space. The electron wave function will simply just appear wherever it wants (within the electron probability cloud). The only way to stop it is to make your insulating junction thicker than the probability cloud.

>"The electron wave function will simply just appear wherever it wants (within the electron probability cloud)."

I don't know which is more ridiculous, the fact that reality works like this, or, that a species of apes was able to figure this out.

  • The experiment to observe this behavior is pretty simple though (Young's double slit), and it was conducted more than 200 years ago. The explanation came much later but it's not like the phenomenon was hiding somewhere.

    • It’s both ridiculous and quite amazing really. The hint that there is something less random underneath it that we just haven’t figured out (and lack the resources to explore at this time) is tantalising.

      Even if there isn’t, the way it seems all based on the uneven flow of state over spacetime is deeply fascinating for someone who studies computing.

  • Reality is far, far stranger than we give it credit for. Makes you wonder what other completely bonkers secrets the universe has for us.

    And frankly, the sheer insanity of quantum teleportation is why I don't buy any argument that faster than light travel is impossible. Not because "teleportation", but because every time we think we understand the rules of the universe, it laughs in our face. The universe is wacky beyond our wildest dreams.

  • I find it ridiculoua that we believe it is random probability instead of trying to find (and maybe later mitigate) the real sources of this randomness.

This is why I suspect we will be neat the upper limits of this around the late 2030's. We are just running too close to the fundamental limits. And so far there isn't anything really radical even on the horizon as a solution for this.

  • Aren't we reaching the point where there is no "solution" in terms of density and physical dimensions?

    It's like the speed of light being a constant, or the Planck length being the smallest that can be subject to standard physics.

    Quantum computing, which is a complete change in the actual physical model of computing, appears to be the only alternative.

    • all production ics have a flat layout with 3d transistors. the physical limit is how close can the features on one wafer get before theres too much tunneling.

      there is a clear way forward with wafer stacking instead of shrinking layouts but so far we only have amd v-cache style asymmetric designs with memory stacked on top of compute. for a fully connected stack that acts like a single chip you need insane precision to align the wafers and a way to remove heat from the middle so the chips dont fry themselves.

      if someone finds a way to stack cpu cores without thermal issues that will be a real revolution. huawei might be close with their logic folding but nobody knows if it really works and what the heat problems are like.

> you can't simply exclude them from any given volume of space...

... inside a silicon crystal.

You can keep the electrons into as small a volume as you want, but you need something there forcing them, and doped silicon will only force them so much.

In fact, those transistors are smaller than what a silicon crystal can do, and the electrons are only held there because they are made of more materials than only silicon.