I think that outside view estimates- “here’s Moore’s Law, this is the point at which the processing power of a human brain will cost the equivalent of $1,000 in 2012 dollars”- are way more robust than inside view estimates- “we just came up with subtechnology 734 out of ~5k necessary.”
it seems much more important than tech 734⁄5000 necessary… carbon nanotubes are one of the core scientific discoveries of our generation and this shows a really interesting property of them directly related to electronics development. The heat dissapation bottleneck has been the most serious issue with nanotech and much, much faster and smaller processors. When we went from faster chips to multiple cores, things became really different—parallel algorithms are inherently more difficult and tech that could reinstate an exponentiation phase is extremely significant. This is more important than that though, if substantiated it is a truly weird physics advance and there’s no telling what applications it will find. The first AI or human decision support system that will offer dangerous self improvement capabilties is most likely going to be on some $10M-$100M system and the question is how do you see that coming? I mentioned moore’s law as the first of many obvious and important areas this advance will impact if there is not some serious engineering bottleneck in putting it into practice, be that in moving up orders of magnitude in clock speed or providing wiring for brain implants that is small enough not to damage neural tissue and so forth. I’m seriously surprised to see a response to this advance that is not at least curious interest at an obviously related physics advance.
I’m seriously surprised to see a response to this advance that is not at least curious interest at an obviously related physics advance.
There are two different things going on here; one of them is that nanotechnology has potential and is interesting, and the other is estimating if/when the next Singularity will occur.
The second is done best by taking the outside view. An estimate that the Singularity will happen in 2100 assumes there will be many technological improvements between then and now- both big and small- and so doesn’t depend on the details- that we fixed the heating problem now and the parallelism problem ten years from now, or did them in the reverse order.
The first is interesting, but should be separated from the second.
“Taking the outside view means using an estimate based on a class of roughly similar previous cases”
so the singularity by far is something after which we cannot predict how things are, but we’re going to look at roughly similar cases for that?
I’m also an insider in this in the sense that I’ve been a professional software engineer for 16 years, dropped out of a phd program after passing qualification exam with a masters in compsci and eng, so yes, I am trying to imagine possible outcomes and look at trajectories and I hope other people with training on this board are doing the same.
so the singularity by far is something after which we cannot predict how things are, but we’re going to look at roughly similar cases for that?
The comparisons people generally make are to agriculture and industrialization.
I’m also an insider in this in the sense that I’ve been a professional software engineer for 16 years
Okay. Part of my academic background is physics, including nanoscale physics- but if anything, being half-educated about it makes me reluctant to speculate.
For example, there’s a technology under development which would use nanotubes and van der Waals forces (if I remember correctly) to do binary memory on a scale that’s a massive jump from what we have now- I think the claim was they could store a petabyte in the volume of a dime. If that works, that’ll be huge- you could significantly change computer architecture with the ability to store abundant memory on the same chip as the CPU, for example. But I’m reluctant to bet that it’ll work until it works.
So if you have a background in nanotech and I have compsci, it seems like speculation could generate ideas.
I think that as a community interested in safety, it’s important we keep informed about the advancement trajectory. Understanding limitations and capabilities of fundamental science advancements also provides intelligence on companies to watch for, tech that is likely available soon and so forth.
so, why not speculate? It’s almost free to scan an idea for value.
It’s interesting and I hadn’t thought of it, but it’s not weird. The losses are from coupling between the substrate and the carrier electrons, so it makes sense that the energy will go there.
What kind of explanation are you looking for? Are you a physicist? Have you taken physics?
Assuming you know some things but aren’t a condensed-matter physicist: 1) single-layered graphene’s intrinsic scattering rate is extremely low, so nearly anything else that causes scattering is going to dominate. 2) it is an exceptionally poor screener of electric fields, due to the low density of states. 3) it is entirely surface, so there is no interior region to be unaffected by boundary effects (though graphene is usually in poor mechanical contact with the substrate, this loose coupling is not weak enough to strongly suppress surface phonon scattering). Note that ‘the top side, away from the substrate’ is not distinct—the relevant carrier electron states straddle the center plane.
So, what happens? You’ve got an electron in the electrical field, accelerating. It eventually scatters. What does it scatter off of? The substrate, mainly, by one mechanism or another. Whichever it is, some energy is dissipated directly into the substrate (that’s what it bounced off of), and the electron bounces off in some other direction. This electron bounce is not heat—the electrical field just goes back to pushing it forward again, and it goes—very orderly except for the isolated scattering instances.
The main ways the graphene itself gets warmer are by a) a carrier electron does manage to scatter off of a graphene lattice phonon (this is a really weak process, but it happens, and when you get rid of the substrate it dominates) ; and b) phonons from the substrate are transmitted into the graphene lattice (this is also weak because graphene binds poorly to the substrates mechanically speaking, but it’s not extremely weak).
That’s the summary of what’s going on. It applies equally to single-walled carbon nanotubes, and to a lesser extent, multi-layered graphene and multi-walled carbon nanotubes.
Thank you or the well considered response, actually helpful. You have my background about right, I published in a physicists in medicine conference and have the normal background in comparch and whatever classes I took for my math double. Definitely not a condensed matter physicist, will have to read more on phonons.
The idea that this is a hollow tube and so there is no interior region to be effected does seem intuitive. The thing that jumped out at me is that the tube itself remained cool.
I don’t have a good understanding of quantum electrodynamics or phonons and that is one reason I wanted to bring this up for discussion. Some types of scattering like bremsstrahlung seem like they play a role, but it doesn’t seem to explain it, from the lead scientist:
“”We believe that the nanotube’s electrons are creating electrical fields due to the current, and the substrate’s atoms are directly responding to those fields,” Cumings explains. “The transfer of energy is taking place through these intermediaries, and not because the nanotube’s electrons are bouncing off of the substrate’s atoms. While there is some analogy to a microwave oven, the physics behind the two phenomena is actually very different.”″
http://newsdesk.umd.edu/scitech/release.cfm?ArticleID=2657
The normal mechanism for heating in electric current transmission as I understand it, the electrons are bouncing off other atoms causing them to vibrate. So we make a transistor or a wire and we a pass a current through it, the atoms inside get hotter and we then dissipate that heat. They don’t appear to think this is what is going on here.
It seems like the electrons go through the nanotube wire and the energy kind of jumps from the current to the tube to the substrate it’s laying on without accumulating much inside the wire itself.
They claim this is a weird game changer which every scientist wants to find, so either that’s hype or it’s legit. It seems like you have a good understanding, this is in a discussion area, what’s your opinion, is this a big discovery that is going to lead to multilayer chips orders of magnitude faster or is it just a fluke thing?
Phonons are the quanta of lattice vibration. Vibrations are one kind of imperfection in a lattice.
Electrical carriers (electrons and holes) do not scatter off of individual lattice atoms; they scatter off of lattice imperfections. These imperfections can be defects, or phonons, or other carriers.
On to the claims in the article… as before. Usefulness? I’m not really sure. If you’re always using these nanotubes to carry currents, their entire environment will heat up (the heat will leak into them eventually), so it seems like it would only really help in cases where it needs to carry a current spike.
If yi would have to do more reading to understand the lattice stuff, it seems reasonable though.
As far as usefulness, the idea I had was you could layer a substrate to dissipate the heat really well. My limited understanding is 85% of the heat jumps the wires somehow and is absorbed by the substrate, which could be engineered arbitrarily. This is important because cnt are very good electrical conductors so you could pair them with a good head absorbing substance and achieve separation of heat and current in ways we have not seen before, which one could speculate as a way to restart moores law progression of speed.
I think that outside view estimates- “here’s Moore’s Law, this is the point at which the processing power of a human brain will cost the equivalent of $1,000 in 2012 dollars”- are way more robust than inside view estimates- “we just came up with subtechnology 734 out of ~5k necessary.”
it seems much more important than tech 734⁄5000 necessary… carbon nanotubes are one of the core scientific discoveries of our generation and this shows a really interesting property of them directly related to electronics development. The heat dissapation bottleneck has been the most serious issue with nanotech and much, much faster and smaller processors. When we went from faster chips to multiple cores, things became really different—parallel algorithms are inherently more difficult and tech that could reinstate an exponentiation phase is extremely significant. This is more important than that though, if substantiated it is a truly weird physics advance and there’s no telling what applications it will find. The first AI or human decision support system that will offer dangerous self improvement capabilties is most likely going to be on some $10M-$100M system and the question is how do you see that coming? I mentioned moore’s law as the first of many obvious and important areas this advance will impact if there is not some serious engineering bottleneck in putting it into practice, be that in moving up orders of magnitude in clock speed or providing wiring for brain implants that is small enough not to damage neural tissue and so forth. I’m seriously surprised to see a response to this advance that is not at least curious interest at an obviously related physics advance.
There are two different things going on here; one of them is that nanotechnology has potential and is interesting, and the other is estimating if/when the next Singularity will occur.
The second is done best by taking the outside view. An estimate that the Singularity will happen in 2100 assumes there will be many technological improvements between then and now- both big and small- and so doesn’t depend on the details- that we fixed the heating problem now and the parallelism problem ten years from now, or did them in the reverse order.
The first is interesting, but should be separated from the second.
Ouch
“Taking the outside view means using an estimate based on a class of roughly similar previous cases”
so the singularity by far is something after which we cannot predict how things are, but we’re going to look at roughly similar cases for that?
I’m also an insider in this in the sense that I’ve been a professional software engineer for 16 years, dropped out of a phd program after passing qualification exam with a masters in compsci and eng, so yes, I am trying to imagine possible outcomes and look at trajectories and I hope other people with training on this board are doing the same.
The comparisons people generally make are to agriculture and industrialization.
Okay. Part of my academic background is physics, including nanoscale physics- but if anything, being half-educated about it makes me reluctant to speculate.
For example, there’s a technology under development which would use nanotubes and van der Waals forces (if I remember correctly) to do binary memory on a scale that’s a massive jump from what we have now- I think the claim was they could store a petabyte in the volume of a dime. If that works, that’ll be huge- you could significantly change computer architecture with the ability to store abundant memory on the same chip as the CPU, for example. But I’m reluctant to bet that it’ll work until it works.
So if you have a background in nanotech and I have compsci, it seems like speculation could generate ideas.
I think that as a community interested in safety, it’s important we keep informed about the advancement trajectory. Understanding limitations and capabilities of fundamental science advancements also provides intelligence on companies to watch for, tech that is likely available soon and so forth.
so, why not speculate? It’s almost free to scan an idea for value.
It’s interesting and I hadn’t thought of it, but it’s not weird. The losses are from coupling between the substrate and the carrier electrons, so it makes sense that the energy will go there.
Would you talk more about the coupling between substrate and carrier electrons, that is not clear to me.
I mean it makes sense that it went somewhere nearby, but why would it transfer at all, only with these particular materials?
Why isn’t it weird to you? If I got a lab report like that i’d be like ok, go ahead and rerun those experiments...
What kind of explanation are you looking for? Are you a physicist? Have you taken physics?
Assuming you know some things but aren’t a condensed-matter physicist: 1) single-layered graphene’s intrinsic scattering rate is extremely low, so nearly anything else that causes scattering is going to dominate. 2) it is an exceptionally poor screener of electric fields, due to the low density of states. 3) it is entirely surface, so there is no interior region to be unaffected by boundary effects (though graphene is usually in poor mechanical contact with the substrate, this loose coupling is not weak enough to strongly suppress surface phonon scattering). Note that ‘the top side, away from the substrate’ is not distinct—the relevant carrier electron states straddle the center plane.
So, what happens? You’ve got an electron in the electrical field, accelerating. It eventually scatters. What does it scatter off of? The substrate, mainly, by one mechanism or another. Whichever it is, some energy is dissipated directly into the substrate (that’s what it bounced off of), and the electron bounces off in some other direction. This electron bounce is not heat—the electrical field just goes back to pushing it forward again, and it goes—very orderly except for the isolated scattering instances.
The main ways the graphene itself gets warmer are by a) a carrier electron does manage to scatter off of a graphene lattice phonon (this is a really weak process, but it happens, and when you get rid of the substrate it dominates) ; and b) phonons from the substrate are transmitted into the graphene lattice (this is also weak because graphene binds poorly to the substrates mechanically speaking, but it’s not extremely weak).
That’s the summary of what’s going on. It applies equally to single-walled carbon nanotubes, and to a lesser extent, multi-layered graphene and multi-walled carbon nanotubes.
Thank you or the well considered response, actually helpful. You have my background about right, I published in a physicists in medicine conference and have the normal background in comparch and whatever classes I took for my math double. Definitely not a condensed matter physicist, will have to read more on phonons.
The idea that this is a hollow tube and so there is no interior region to be effected does seem intuitive. The thing that jumped out at me is that the tube itself remained cool.
I don’t have a good understanding of quantum electrodynamics or phonons and that is one reason I wanted to bring this up for discussion. Some types of scattering like bremsstrahlung seem like they play a role, but it doesn’t seem to explain it, from the lead scientist:
“”We believe that the nanotube’s electrons are creating electrical fields due to the current, and the substrate’s atoms are directly responding to those fields,” Cumings explains. “The transfer of energy is taking place through these intermediaries, and not because the nanotube’s electrons are bouncing off of the substrate’s atoms. While there is some analogy to a microwave oven, the physics behind the two phenomena is actually very different.”″ http://newsdesk.umd.edu/scitech/release.cfm?ArticleID=2657
The normal mechanism for heating in electric current transmission as I understand it, the electrons are bouncing off other atoms causing them to vibrate. So we make a transistor or a wire and we a pass a current through it, the atoms inside get hotter and we then dissipate that heat. They don’t appear to think this is what is going on here.
It seems like the electrons go through the nanotube wire and the energy kind of jumps from the current to the tube to the substrate it’s laying on without accumulating much inside the wire itself.
They claim this is a weird game changer which every scientist wants to find, so either that’s hype or it’s legit. It seems like you have a good understanding, this is in a discussion area, what’s your opinion, is this a big discovery that is going to lead to multilayer chips orders of magnitude faster or is it just a fluke thing?
Phonons are the quanta of lattice vibration. Vibrations are one kind of imperfection in a lattice.
Electrical carriers (electrons and holes) do not scatter off of individual lattice atoms; they scatter off of lattice imperfections. These imperfections can be defects, or phonons, or other carriers.
On to the claims in the article… as before. Usefulness? I’m not really sure. If you’re always using these nanotubes to carry currents, their entire environment will heat up (the heat will leak into them eventually), so it seems like it would only really help in cases where it needs to carry a current spike.
If yi would have to do more reading to understand the lattice stuff, it seems reasonable though.
As far as usefulness, the idea I had was you could layer a substrate to dissipate the heat really well. My limited understanding is 85% of the heat jumps the wires somehow and is absorbed by the substrate, which could be engineered arbitrarily. This is important because cnt are very good electrical conductors so you could pair them with a good head absorbing substance and achieve separation of heat and current in ways we have not seen before, which one could speculate as a way to restart moores law progression of speed.