4 ms·

It seems complicated to let our materials get damaged and then try to fix them on the fly. The earth protects itself from charged particles via a gigantic dipol

by jayajay 10y ago

It seems complicated to let our materials get damaged and then try to fix them on the fly. The earth protects itself from charged particles via a gigantic dipole field. Could the same be done with nano-electronics? Boards could be designed to generate magnetic fields via embedded current loops. Instead of having a wire connect two components in a straight line (shortest path approach), it could be done in a way that meanders around, intentionally creating large curls. Since we're talking about scales of 1e-9m, these fields would probably be pretty strong. Now, I don't know too much about superconductors, but vacuum tends to be pretty fucking cold (2K -- surely, lower than the critical temperature for many superconducting materials). It might even be possible to create a Meissner cage around the important components, in a way that protects our components from self-harm, while still protecting them from external charged particles. Has this theory been tested? After all, it works for the Earth. I am afraid doing that might also be detrimental to our electronic components (unless we can somehow create a diamagnetic cage to selectively protect our components).

HCIdivision17 10y ago
I think the main problem is of scale. The Earth's field isn't too strong, but it is huge in expanse. That's a lot of distance to deflect and decelerate. Going from a million meter diameter to a billionth likely requires a honking big*large field strength to deflect as hard. Also while space has a very low temperature, it's an impressively terrible conductor of heat and thus a garbage cold sink. To keep things cool you either have to wait for the heat to radiate out or to off gas your coolant. You could generate radiative fins for the chips, but I don't know how effective that is in space; I would assume they would be so gossamer it would be hard to keep them from corroding in the solar wind. But maybe that's just an engineering problem.
- jayajay 10y ago
  https://www.google.ch/patents/US7157290 https://www.google.ch/patents/US7157290 It looks like these people have patented a classical/macroscopic version of a similar idea. They talk about using a completely separate solenoid to deflect incoming ions. Unfortunately they don't do any calculations (none that I could find) to see if it would even work? What I'm suggesting is a bit different - a change to the transistor and microscopic wire structure so that components would be protected from external charges via self produced magnetic fields. So, it would look like a bunch of little spins on a grid, some activated, some not activated, like 2D-Ising pretty much, but not random -- the directions are defined by the logic running on the board. I think you are right, though. These B fields act over too short a distance in order to allow a relativistic particle to radiate an appreciable amount of energy before doing damage.
  - HCIdivision17 10y ago
    There's definitely an effect, but from my intuition I'd guess it'd have to be fairly strong. But maybe if they're cheap enough to produce and easy enough to mass up, you don't have to even be that effective. Here's where my intuition is anchored, and you can figure if it's applicable (because I worked in a very different field). In magnetron sputtering, you ionize a gas as it passes through a strong magnetic field (harddrive magnet strength). Once the molecule ionizes (since it's moving at sonic speeds in the vacuum), it whips around and slams into some target, blasting molecules back from the target like a shotgun to a pile of dirt. These sputtered molecules/bits of material may be slightly charged, and when they hit the substrate will carry that charge and deposit it onto the substrate. Over time an insulating substrate (like glass) will charge up a bit, and this will begin to repulse incomming splattered charged bits. It'd be called something like 'biasing' and slows down the deposition rate, since the incomming material may slow too much to properly embed itself on the substrate. The magnets behind the target also trap electrons (in what is often called a racetrack), which helps amplifies ionizing the gases (since a strong field may not ionize the incoming gas molecules, but plonking an extra electron onto it will). It tends to be a game of small effects in big numbers. Any individual interaction can vary wildly from one interaction to another, but over many trillions of trillions of events it averages out like you'd expect scales similar to Avagadro's number to. So if we could fabricate stupefying amouts of these gizmos, you wouldn't need it to be completely effective; just enough biasing or field strength to tilt the odds a bit in your favor and a lot of the little chips could survive. And if you have enough, you win! Sure the solor wind may clobber a few chips, but if you have billions enough of them, perhaps enough survive to keep effective. This is part of the approach to some MEMS gizmos, where you play the odds and make huge numbers of the gizmos with a cheap fast process and filter out the working ones. Ideally you'd be smart and just have a really good process, but if your fabrication process is messy or too hard to control and the gizmo valuable enough you can take the losses. (I mean, you don't do that - you engineer good processes! But... well, that can be expensive. And sometimes waste is cheaper.) EDIT: I'm thinking of the spherical cow equivalent of a gizmo here, too. You prolly wouldn't make billions of little computers and hork them at another star system unless you could essentially replicate them chemically. But not with a photolithographic process typical to chip designs. You can get millions, not trillions of trillions. Have something that self-assembles in a beaker and then perhaps it becomes an option. But that's sort of like hurling a viral infection at another star system, and... well, kinda gunks the idea too.
LeanderK 10y ago
this question always pops up when i read stuff like this. Why are we never considering creating an artificial magnetic field? You could protect spaceships or settlements on mars. How much power would be required for either those things and what's the deal-breaker? Getting the power?
- T-A 10y ago
  It has been considered. This, http://www.islandone.org/Settlements/MagShield.html http://www.islandone.org/Settlements/MagShield.html is from 1991, but AFAIK the magnets available then were not significantly worse than what we have now: https://en.wikipedia.org/wiki/Neodymium_magnet https://en.wikipedia.org/wiki/Neodymium_magnet

by jayajay 10y ago

HCIdivision17 10y ago

I think the main problem is of scale. The Earth's field isn't too strong, but it is huge in expanse. That's a lot of distance to deflect and decelerate. Going from a million meter diameter to a billionth likely requires a honking big*large field strength to deflect as hard. Also while space has a very low temperature, it's an impressively terrible conductor of heat and thus a garbage cold sink. To keep things cool you either have to wait for the heat to radiate out or to off gas your coolant. You could generate radiative fins for the chips, but I don't know how effective that is in space; I would assume they would be so gossamer it would be hard to keep them from corroding in the solar wind. But maybe that's just an engineering problem.

jayajay 10y ago
https://www.google.ch/patents/US7157290 https://www.google.ch/patents/US7157290 It looks like these people have patented a classical/macroscopic version of a similar idea. They talk about using a completely separate solenoid to deflect incoming ions. Unfortunately they don't do any calculations (none that I could find) to see if it would even work? What I'm suggesting is a bit different - a change to the transistor and microscopic wire structure so that components would be protected from external charges via self produced magnetic fields. So, it would look like a bunch of little spins on a grid, some activated, some not activated, like 2D-Ising pretty much, but not random -- the directions are defined by the logic running on the board. I think you are right, though. These B fields act over too short a distance in order to allow a relativistic particle to radiate an appreciable amount of energy before doing damage.
- HCIdivision17 10y ago
  There's definitely an effect, but from my intuition I'd guess it'd have to be fairly strong. But maybe if they're cheap enough to produce and easy enough to mass up, you don't have to even be that effective. Here's where my intuition is anchored, and you can figure if it's applicable (because I worked in a very different field). In magnetron sputtering, you ionize a gas as it passes through a strong magnetic field (harddrive magnet strength). Once the molecule ionizes (since it's moving at sonic speeds in the vacuum), it whips around and slams into some target, blasting molecules back from the target like a shotgun to a pile of dirt. These sputtered molecules/bits of material may be slightly charged, and when they hit the substrate will carry that charge and deposit it onto the substrate. Over time an insulating substrate (like glass) will charge up a bit, and this will begin to repulse incomming splattered charged bits. It'd be called something like 'biasing' and slows down the deposition rate, since the incomming material may slow too much to properly embed itself on the substrate. The magnets behind the target also trap electrons (in what is often called a racetrack), which helps amplifies ionizing the gases (since a strong field may not ionize the incoming gas molecules, but plonking an extra electron onto it will). It tends to be a game of small effects in big numbers. Any individual interaction can vary wildly from one interaction to another, but over many trillions of trillions of events it averages out like you'd expect scales similar to Avagadro's number to. So if we could fabricate stupefying amouts of these gizmos, you wouldn't need it to be completely effective; just enough biasing or field strength to tilt the odds a bit in your favor and a lot of the little chips could survive. And if you have enough, you win! Sure the solor wind may clobber a few chips, but if you have billions enough of them, perhaps enough survive to keep effective. This is part of the approach to some MEMS gizmos, where you play the odds and make huge numbers of the gizmos with a cheap fast process and filter out the working ones. Ideally you'd be smart and just have a really good process, but if your fabrication process is messy or too hard to control and the gizmo valuable enough you can take the losses. (I mean, you don't do that - you engineer good processes! But... well, that can be expensive. And sometimes waste is cheaper.) EDIT: I'm thinking of the spherical cow equivalent of a gizmo here, too. You prolly wouldn't make billions of little computers and hork them at another star system unless you could essentially replicate them chemically. But not with a photolithographic process typical to chip designs. You can get millions, not trillions of trillions. Have something that self-assembles in a beaker and then perhaps it becomes an option. But that's sort of like hurling a viral infection at another star system, and... well, kinda gunks the idea too.

LeanderK 10y ago

this question always pops up when i read stuff like this. Why are we never considering creating an artificial magnetic field? You could protect spaceships or settlements on mars. How much power would be required for either those things and what's the deal-breaker? Getting the power?

T-A 10y ago
It has been considered. This, http://www.islandone.org/Settlements/MagShield.html http://www.islandone.org/Settlements/MagShield.html is from 1991, but AFAIK the magnets available then were not significantly worse than what we have now: https://en.wikipedia.org/wiki/Neodymium_magnet https://en.wikipedia.org/wiki/Neodymium_magnet