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US Nuclear Weapons Lab Discovers How To Suppress the Casimir Force

Soulskill posted about 9 months ago | from the requires-application-of-Casimir's-Oil dept.

The Military 112

KentuckyFC writes "One of the frustrating problems with microelectromechanical (MEM) devices is that the machinery can sometimes stick fast, causing them to stop working. One of the culprits is the Casimir effect — an exotic force that pushes metallic sheets together when they are separated by tiny distances. Now physicists at the Los Alamos National Laboratory in New Mexico have worked out and demonstrated how to suppress the Casimir force. The trick is to create a set of deep grooves and ridges in the surface of one sheet so that the other only comes close to the tips of the ridges. These tips have a much smaller surface area than the flat sheet and so generate much less force. That could help prevent stiction in future MEMs devices. But why would a nuclear weapons lab be interested? MEM devices are invulnerable to electromagnetic pulse weapons that fry transistor-based switches, and so could be used as on-off switches for nuclear devices."

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112 comments

reads like a sleasy click ad. (-1, Flamebait)

Anonymous Coward | about 9 months ago | (#45103963)

Single Mom discovers how to Suppress The Casimir Force with this one neat trick!
[picture of a police car] ...
Obama sends single mothers back to school!
[picture of a homeless man] ...

Not Nuclear Weapons Lab (5, Informative)

goombah99 (560566) | about 9 months ago | (#45104059)

Los Alamos is a National Laboratory. It's not a "Nuclear Weapons Laboratory". It sequences Genomes, it works on carbon nanotubes, it develops remote sensing, it does particle physics, it works on biofuels, and proteins, and medicine. You might as well say Stanford University is a place where they develop internet search engines, and General electric makes nuclear reactors.

Re:Not Nuclear Weapons Lab (4, Funny)

Anonymous Coward | about 9 months ago | (#45104103)

You might as well say Stanford University is a place where they develop internet search engines, and General electric makes nuclear reactors.

Well, neither of those would be untrue.

Re:Not Nuclear Weapons Lab (0)

Anonymous Coward | about 9 months ago | (#45104167)

I can say that you are a person that produces feces. That's a fact, but that doesn't define you. I hope.

Re:Not Nuclear Weapons Lab (1)

Anonymous Coward | about 9 months ago | (#45104217)

Well my wife might say it does...

Re: Not Nuclear Weapons Lab (1)

Anonymous Coward | about 9 months ago | (#45104871)

Better a producer than a consumer

Re:Not Nuclear Weapons Lab (0)

Anonymous Coward | about 9 months ago | (#45105291)

maybe the pellets they are imploding are rabbit pellets.

jr

Re:Not Nuclear Weapons Lab (5, Informative)

Anonymous Coward | about 9 months ago | (#45104597)

Los Alamos is a National Laboratory. It's not a "Nuclear Weapons Laboratory". It sequences Genomes...

Los Alamos is very much a nuclear weapons laboratory, one of three in the US. Los Alamos and Lawrence Livermore are responsible for the (about a dozen) nuclear parts of nuclear weapons whereas Sandia, considered an engineering rather than physics laboratory, is responsible for the (thousands of) non-nuclear parts of nuclear weapons. All three are national laboratories and work on all sorts of other things, but they are the only ones responsible for designing the US nuclear arsenal.

Re:Not Nuclear Weapons Lab (1)

Penguinisto (415985) | about 9 months ago | (#45104679)

True, but if you want to pick semantics, well...

Los Alamos has a "Nuclear Weapons Laboratory" on the premises, and it is that laboratory (or more specifically, the scientists within it that work on nuclear weaponry and related concepts) which produced the switch with the funny pattern on the contacts. ...but then "Scientist At The Nuclear Weapons Laboratory Sited Within The Realm Of What Is Known As Los Alamos" just doesn't quite fit too well on a business card (let alone a headline), does it? ;)

(...mind you, I'm just typing this in jest. I get your point, but really, precision is not always possible or even practical.)

Signed,
Some Guy Who Lives Where They "Put A Bird On It"

Re:Not Nuclear Weapons Lab (0)

Anonymous Coward | about 9 months ago | (#45104773)

You forgot, that's where they make the probes to stick in the alien butts.

Re:Not Nuclear Weapons Lab (0)

Anonymous Coward | about 9 months ago | (#45104901)

Los Alamos is a National Laboratory. It's not a "Nuclear Weapons Laboratory". It sequences Genomes, it works on carbon nanotubes, it develops remote sensing, it does particle physics, it works on biofuels, and proteins, and medicine.

Obviously, the gene sequencing is to make better nuclear physicists. The proteins and medicine keep them fed and healthy. Remote sensing is for better targeting. Biofuels are for launching the rockets. Particle physics is for better weapons packages.

That just leaves one question:
WHAT ARE THE NANOTUBES FOR?

LANL budget: mostly nuclear weapons (4, Insightful)

mbkennel (97636) | about 9 months ago | (#45105191)

http://www.lanl.gov/about/facts-figures/budget.php#.UlhzcVCshcY

NNSA Weapons programs 57%: 1.263B
NNSA Nonproliferation (also about nuclear weapons): 9% 210M
NNSA Safeguards & Security (also about nuclear weaopns) 7% 152M
DOE Environmental Management (cleanup junk) 8% 187 M
DOE Energy and other Programs, 4% 84M (unclear, nuclear reactors perhaps?)
DOE Office of Science, 4% 94M
Work For Others, 4%, 98M
Work For Others (National Security), 7% 154M

So by far most of LANL's budget involves nuclear weapons, and cleaning up from producing and testing nuclear weapons. Then after that unspecified work for "National Security", which is probably scientific services to the Intelligence Community.

Then, there's the 4% which is basic science like "particle physics, it works on biofuels, and proteins, and medicine" and there may be some science in the 4% of "DOE Energy and Other Programs".

I too was pretty surprised how small the basic science budget is, and I'm a physicist.

Calling LANL a "Nuclear Weapons Laboratory" is about as correct as calling Microsoft a "software company", even though they do make keyboards and mice and a tablet.

Re:Not Nuclear Weapons Lab (0)

Anonymous Coward | about 9 months ago | (#45106785)

Los Alamos is a weapons laboratory, genius. Wishing it wasn't so doesn't make it so.

Exotic forces? (-1)

Anonymous Coward | about 9 months ago | (#45103967)

You monkeys still confuse atomic forces, magnetism and gravity. It's so cute.

brilliant! (-1)

Anonymous Coward | about 9 months ago | (#45103975)

reduction of surface area leads to reduction of effect. imagine that. duh. why didn't they try that sooner? that woulda been top on my list.

Re:brilliant! (5, Funny)

NettiWelho (1147351) | about 9 months ago | (#45104007)

reduction of surface area leads to reduction of effect. imagine that. duh. why didn't they try that sooner? that woulda been top on my list.

Then it is most unfortunate you didn't share this information with them years ago, asshole.

Re:brilliant! (-1)

Anonymous Coward | about 9 months ago | (#45104549)

i was actually thinking the same thing. seemed kind of obvious to me. guess i'm an asshole too. pucker up and kiss me, bitch.

Re:brilliant! (1)

vyvepe (809573) | about 9 months ago | (#45104839)

i was actually thinking the same thing

Me too.

Re:brilliant! (0)

Anonymous Coward | about 9 months ago | (#45105435)

reduction of surface area leads to reduction of effect. imagine that. duh. why didn't they try that sooner? that woulda been top on my list.

Then it is most unfortunate you didn't share this information with them years ago, asshole.

i was actually thinking the same thing. seemed kind of obvious to me. guess i'm an asshole too. pucker up and kiss me, bitch.

i was actually thinking the same thing

Me too.

Dark Helmet: Who is he?
Colonel Sandurz: He's an asshole sir.
Dark Helmet: I know that! What's his name?
Colonel Sandurz: That is his name sir. Asshole, Major Asshole!
Dark Helmet: And his cousin?
Colonel Sandurz: He's an asshole too sir. Gunner's mate First Class Philip Asshole!
Dark Helmet: How many asholes do we have on this ship, anyway?

Re:brilliant! (1)

Penguinisto (415985) | about 9 months ago | (#45104703)

Well technically, the technique increases surface area (they use something similar on solar cells to increase efficiency), but yeah - otherwise good point. :)

Re:brilliant! (1)

InvalidError (771317) | about 9 months ago | (#45105423)

There is no information to share.

Contact surface area has always been a major factor in static and dynamic friction forces in conventional mechanics (ex.: ball bearings) so this "discovery" is nothing more than scientists re-discovering something obvious that they forgot for some reason: reducing contact surface area works at microscopic scales too.

On macroscopic mechanics, surface roughness is a major contributor to friction. On a microscopic scale, roughness is replaced by atomic forces but the rest is still the same.

Re:brilliant! (1, Informative)

sfm (195458) | about 9 months ago | (#45104071)

Breakthrough?
This technique has been used for years in the manufacture of MEMS sensors.
Ridges, bumps and non-perpendicular geometries all tend to reduce the surface
to surface contact area and are standard in MEMS gyroscope and accelerometer
designs, used to combat "Stiction".

While interesting, this is not new news.

Re:brilliant! (1)

onix (990980) | about 9 months ago | (#45104149)

Maybe you should read the article first.

Re:brilliant! (1)

dimeglio (456244) | about 9 months ago | (#45104283)

Funny, given the Casimir effect, I would have thought that non-perpendicular geometries (such as parallel) increase risk of surface to surface contact.

Re:brilliant! (1)

sfm (195458) | about 9 months ago | (#45104677)

Oops, you are right. That should have read "non-parallel surfaces"
Thanks for the feedback

Re:brilliant! (2)

nospam007 (722110) | about 9 months ago | (#45104809)

"Breakthrough?
This technique has been used for years in the manufacture of MEMS sensors."

There are other uses of it too, here's the link to the video from the Orchid orientation tape.
http://www.youtube.com/watch?v=NY3dY3Cx-DM [youtube.com]

Re:brilliant! (1)

sjames (1099) | about 9 months ago | (#45105459)

Read the actual paper, they did more than TFS implies.

Re:brilliant! (0)

Anonymous Coward | about 9 months ago | (#45104073)

reduction of surface area leads to reduction of effect. imagine that. duh. why didn't they try that sooner? that woulda been top on my list.

Just like friction! Oh, wait...

Re:brilliant! (1)

onix (990980) | about 9 months ago | (#45104335)

Yes, but can you explain friction?

Re:brilliant! (4, Funny)

stewsters (1406737) | about 9 months ago | (#45104121)

I once had an similar idea about reducing the force of gravity on rockets. Basically make them with less mass, and as mass goes to zero then the force required to launch them into space also goes to zero. Genius.

Re:brilliant! (0)

Anonymous Coward | about 9 months ago | (#45104645)

I have a much superior idea. I bet if you go past zero to negative mass all your rocket problems are solved.

Re:brilliant! (4, Insightful)

sycodon (149926) | about 9 months ago | (#45104207)

So they didn't really suppress anything, they just prevented the circumstances that would be subject to the effect.

Wouldn't it be the case that if they actually manipulated a fundamental nuclear force that it would be a very notable achievement? Rght up there with negating gravity or something.

Re:brilliant! (1)

Anonymous Coward | about 9 months ago | (#45104273)

Um, it is a INCREASE in the surface area.
It's that very increase in the area, coupled with the geometry of the object that negates the force as the average space between the two objects is now large enough to allow enough virtual particles to form and negate the the push of the virtual particles on the outside of the objects.

Re:brilliant! (2, Funny)

Anonymous Coward | about 9 months ago | (#45104415)

Um, it is a INCREASE in the surface area.

not in the part (the 'pointy' bits) that's closest to the other (flat) surface...

___ ___
--- ^^^

Re:brilliant! (1)

HiThere (15173) | about 9 months ago | (#45105793)

While the idea is trivially obvious, the implementation is a bit difficult. What they've discovered isn't theory, but technology. And telling them what they should try first wouldn't help if you don't also tell them how to try it.

FWIW, the Casimir effect is normally quite difficult to observe, because it only appears when two extrememly flat pieces of conductor are brought close enough together to suppress virtual particle pair production. This causes the space between the two flat pieces of metal to have a lower energy level that the space outside, where virtual pair production isn't suppressed. And THAT is what tries to push the two pieces of conductive material closer together.

Now for a mem, this will generally be in the form of a cylinder within a cylinder, which will tend to be dynamically pushed off center. So you're talking about doing machining on smooth pieces of metal that are extremely small, and which will still end up with making contact on one side. Rails, which is what this sounds like, then need to be not only small, but smooth and sharp. Not a simple machining problem. And you probably need three or four of them on each cylinder. And they must be extremely smooth, because ordinary lubricants won't work in this environment. (Think vacuum contact welds.) This probably means that the rails need to be of a different material than the thing they make contact with, but with the same default electric charge. (At this point I'm guessing wildly. But you get the kind of thing that needs to be considered.)

Just saying rails doesn't help that much.

Oh goody. Better nukes. (0)

Anonymous Coward | about 9 months ago | (#45103985)

Just great.

Invulnerable? Really? (2, Insightful)

Toad-san (64810) | about 9 months ago | (#45103997)

"MEM devices are invulnerable to electromagnetic pulse weapons that fry transistor-based switches,"

I don't know why that would be true. We're talking about a very small mechanical switch, right? Two metallic surfaces (presumably at the end of wires or traces) that connect to close a circuit? The high voltage surge usually associated with an EMP would jump (and weld) micro-teensy-tiny switches just as easily as big ones. You've never seen a mechanical switch welded by an unexpected high voltage or amperage surge? I have. No reason why that won't happen with an MEM device. I'll have to see a better reference to proof of that surge invulnerability before I buy into this.

Re:Invulnerable? Really? (1)

Deluvianvortex (2908365) | about 9 months ago | (#45104097)

the switch itself will survive. Also, when they say EMP they mean on microscopic scales, not like the emp that is emitted when a nuke goes off. Transistors won't work here because of how they're made, but all this is, essentially, is a piece of metal.

Re:Invulnerable? Really? (1)

CanHasDIY (1672858) | about 9 months ago | (#45104193)

...when they say EMP they mean on microscopic scales, not like the emp that is emitted when a nuke goes off.

The use of the phrase "electromagnetic weapons" in the summary kinda belies that hypothesis.

Re:Invulnerable? Really? (1)

Deluvianvortex (2908365) | about 9 months ago | (#45104669)

But you still need a triggering mechanism for that weapon that is immune to EMP surges. Think about it: if the bomb goes off then you don't really worry about what condition the switch is in, because it going to be vaporized. You can alternatively not park your weapons next to emp sources but you need to make sure they won't accidently detonate if they are.

Re:Invulnerable? Really? (1)

CanHasDIY (1672858) | about 9 months ago | (#45104829)

My point was that an electromagnetic pulse weapon would not be microscopic in scale, thus negating OP's conjecture. Granted, it probably wouldn't give off nuclear-detonation-levels of EMR, but it sure as hell wouldn't be "microscopic" either.

Re:Invulnerable? Really? (1)

Deluvianvortex (2908365) | about 9 months ago | (#45104927)

Perhaps, though, I was thinking about this, and its not that the switch will accidentally activate, its that it will nullify itself so it will NEVER activate, making the bomb a 1 billion dollar dud. Think about it: If you're busy nuking the landscape, what happens if one bomb goes off and burns all the triggers for the rest of the bombs? Then your entire war strategy has to be adjusted or scrapped.

Re:Invulnerable? Really? (1)

HiThere (15173) | about 9 months ago | (#45105831)

That sounds like a benefit alright, but wouldn't transistors work just as well?

Re:Invulnerable? Really? (5, Interesting)

wagnerrp (1305589) | about 9 months ago | (#45104109)

An isolated MEMS is immune to electromagnetic pulses as the atmospheric saturation voltage is too low to produce sufficient potential in a system that small to damage it. If the MEMS is electrically connected to larger external systems, the potential across the contact points could be sufficient to cause damage.

Re:Invulnerable? Really? (1)

fuzzyfuzzyfungus (1223518) | about 9 months ago | (#45104113)

I'd imagine that 'invulnerable' is hyperbole; but I would tend to suspect that MEM gear is less touchy than semiconductors, especially modern very-high-density compute logic(on recent x86 CPUs, loss of magic smoke is a distinct possibility at vCore of 2 volts or less (never mind if you do something genuinely impolite like reversing power and ground...))

I assume that the nuke jockies use older, better hardened, stuff; but semiconducters small enough for serious computing purposes are real wimps(SCR pucks large enough to be used as blunt weapons, not so much; but we need to fit the computer inside the missile, no?).

Re:Invulnerable? Really? (1)

bob_super (3391281) | about 9 months ago | (#45104153)

The high voltage surge usually associated with an EMP would jump (and weld) micro-teensy-tiny switches just as easily as big ones

Electrical fields are expressed in V/m. If you have a micro-switch, you get a microvoltage. Now, the air breakdown is also in V/m, so you may still get a spark in all things are proportional, but the energy won't be there to weld anything shut.

Re:Invulnerable? Really? (0)

Anonymous Coward | about 9 months ago | (#45104337)

Oh yes, very small. Very small scale. Like, sub-atomic scale. No! Even smaller, like the size of the components in a computer more powerful than a human brain contained in a size of a quark. That's very small you know. I'm sure that you could put more than a dozen of those on the end of a child's hair.

Obvious/Common sense wins again (-1)

Anonymous Coward | about 9 months ago | (#45104001)

Obvious/Common sense wins again

Seriously, it takes Triple PHD students to think of reducing surface area to reduce the chances of the force?

My god IQ's have dropped whilst I have been away.

This seems more of an education failure than a science win.

Re:Obvious/Common sense wins again (1)

onix (990980) | about 9 months ago | (#45104141)

Did you read the link? Quoting: "Various physicists speculate that by choosing the right combination of geometries, it may be possible to make the force repulsive. That would be handy in preventing problems such as stiction. But nobody has been able to say for sure how this might be done." Explain that O Wise One. Maybe it's not possible, but those ignorant think everything is simple but what they do... let me guess, you are a wannabe hacker.

Re:Obvious/Common sense wins again (0, Interesting)

Anonymous Coward | about 9 months ago | (#45104333)

Make the force repulsive? Um, no. The force arises as the difference between the sum of energies of different wavelengths outside the gap versus those inside the gap.

Unless you can figure out a way to make the gap bigger on the inside than on the outside, which would be cool and lead to technologies like a bag-of-holding, if not a full-fledged TARDIS, you're out of luck.

Sure, physicists can speculate on which combination of geometries might make a TARDIS possible, but nobody has been able to say for sure how this might be done.

Re:Obvious/Common sense wins again (1)

onix (990980) | about 9 months ago | (#45104183)

Also, this is about testing theories. They mean nothing without experimental backup. Add to that the ability to make uniform 0.1 micron ridges that are 0.2 microns deep. Let's see if you even know how to begin to do that first before you speak. Clearly the nuance of science is lost on you. If you have a PhD, I wish to take it back.

Re:Obvious/Common sense wins again (0)

Anonymous Coward | about 9 months ago | (#45104471)

I am very sure these super smart PHD's can be replaced by a very small genetic algorithm script.

This is no good (1)

fustakrakich (1673220) | about 9 months ago | (#45104025)

Neutralizing all weapons is a worthwhile goal. How are we going to defend ourselves against them now? More nukes? I'm hoping for something a little less harmful...

Re:This is no good (1)

CanHasDIY (1672858) | about 9 months ago | (#45104203)

Neutralizing all weapons is a worthwhile goal. How are we going to defend ourselves against them now? More nukes? I'm hoping for something a little less harmful...

Engineered plague would be the obvious solution; no need to worry about nukes if there's no one alive to launch them!

OK, so maybe not an ideal solution, but hey - it solves the problem. I call that a win.

Let me guess... (2)

Overzeetop (214511) | about 9 months ago | (#45104235)

You work for the US congress, don't you.

Re:Let me guess... (2)

CanHasDIY (1672858) | about 9 months ago | (#45104439)

Not yet, although I do admit I've been considering taking a run at it.

Do you think a general lack of respect for human life is enough to overcome the absence of campaign funding, or do I need to pick some pet issue to go 50-kinds-of-stupid with as well?

Re:Let me guess... (0)

Anonymous Coward | about 9 months ago | (#45104863)

Ahh, a rookie, I see. Allow me to clear up some obvious misunderstandings:

- Sorry, there is nothing that will overcome your absence of campaign funding. If you don't accept money, you don't qualify, plain and simple.

- You don't get to pick your pet issue to go 50-kinds-of-stupid with. The people who fund your campaign do that.

Thermionic valves also work (3, Interesting)

jd (1658) | about 9 months ago | (#45104035)

Totally immune to EMP. Besides, we need people to magnify the Casimir effect if we're to ever get wormhole technology. And, trust me on this, you do NOT want an evil general on the other side to go around suppressing it when you're half-way through.

Re:Thermionic valves also work (5, Funny)

fuzzyfuzzyfungus (1223518) | about 9 months ago | (#45104123)

Totally immune to EMP. Besides, we need people to magnify the Casimir effect if we're to ever get wormhole technology. And, trust me on this, you do NOT want an evil general on the other side to go around suppressing it when you're half-way through.

Plus, ICBMs controlled by valves just have a 'warmer' trajectory. It's hard to describe; but the flight path just isn't nearly as 'harsh' as semiconductor ICBMs.

Re:Thermionic valves also work (0)

Anonymous Coward | about 9 months ago | (#45104581)

That may be the case, but the oxygen free copper cables connecting them to the power supply are a real drag.

No atomic matter "immune" (1)

Roger W Moore (538166) | about 9 months ago | (#45104165)

Totally immune to EMP.

Nothing made of atoms is immune to EMP. A sufficiently large EM field will rip atoms apart and convert the object to plasma. The words you are looking for are "less susceptible".

Re:No atomic matter "immune" (0)

Anonymous Coward | about 9 months ago | (#45104711)

A sufficiently large EM field will rip atoms apart and convert the object to plasma.

At that point, the thing the switch controls will no longer exist.

Black hole weapons are hard to defend against too, but I don't think the US military worries about that.

Re:No atomic matter "immune" (1)

Roger W Moore (538166) | about 9 months ago | (#45105819)

True but well before being turned to plasma induced eddy currents will likely melt parts of the valve and cause it to fail. The point is that other switch technologies may be far less susceptible but if you go around thinking they are completely immune you may get a nasty surprise at some point and, if you are dealing with nuclear weapons, it's probably wise to avoid nasty surprises.

Re:Thermionic valves also work (1)

xupere (1680472) | about 9 months ago | (#45104525)

Besides, we need people to magnify the Casimir effect if we're to ever get wormhole technology.

Increase the surface area with a series of (complementary) deep grooves and ridges?

What about our own grooves and ridges? (0)

Anonymous Coward | about 9 months ago | (#45104663)

Besides, we need people to magnify the Casimir effect if we're to ever get wormhole technology.

Increase the surface area with a series of (complementary) deep grooves and ridges?

Or perhaps we need people to magnify the Casimir effect, so we need smarter brains, perhaps with more grooves and ridges.

Re:Thermionic valves also work (1)

Grog6 (85859) | about 9 months ago | (#45105051)

Oddly enough, Nukes DO run on tubes, lol.

http://en.wikipedia.org/wiki/Krytron [wikipedia.org]

There are much newer variants, I'd bet, since the 40's.

It's really hard to set off that many explosives to within a few nanoseconds of "exactly the right time"; an electric plasma pretty much wins out every time. :)

Re:Thermionic valves also work (0)

Anonymous Coward | about 9 months ago | (#45107003)

you do NOT want an evil general on the other side to go around suppressing it when you're half-way through.

Taken out of context, this sounds really painful.

Babbage targeting computers in nukes! Sweet! (2)

zerosomething (1353609) | about 9 months ago | (#45104077)

So they are making Babbage mechanical computers in them nukes! Got to love problem solving. But the G loads have to cause problems on those devices, don't they? Timing errors and such?

Prior Technology (0)

leftover (210560) | about 9 months ago | (#45104083)

This is centuries-old hat in all kinds of precision equipment. Just think about the slides on the massive old machine tools. They are crisscrossed with grooves and the flat surfaces are flaked to reduce contact and let slide oil help keep the metal surfaces apart.

Whoever launched this as an amazing new discovery should be painfully embarrassed. Don't even want to spend time for links - just search if you're interested.

Re:Prior Technology (5, Interesting)

Anonymous Coward | about 9 months ago | (#45104191)

Not sure if I agree. I think the research is interesting. (Also, the Casimir force is _not_ like friction: it appears in conductive materials only.)

1. They've managed to make the super-tiny grooves needed at an unheard of precision. Sub-100 nm features have little in common with grooved surfaces.
2. The grating they've developed confirms the prediction that Casimir force is proportional to area.
3. The grating has effects going beyond existing theory:

Replacing a flat surface with a deep metallic lamellar grating with sub-100 nm features strongly suppresses the Casimir force and for large inter-surfaces separations reduces it beyond what would be expected by any existing theoretical prediction. (Abstract)

Re:Prior Technology (2)

Born2bwire (977760) | about 9 months ago | (#45106309)

The Casimir force occurs for non-conductive materials too. Lifshitz did a famous treatment for dielectric slabs.

Re:Prior Technology (1)

sumdumass (711423) | about 9 months ago | (#45104631)

I believe what you are talking about is called knurling. It is commonly used on valve guides for high performance engines to specifically decrease what is known as sticktion. But it is often used as you say also. It has been around for a long time.

Re:Prior Technology (1)

EETech1 (1179269) | about 9 months ago | (#45106949)

it's called frosting, and it's done with a scraper. I took a machine rebuilding class, and we had to scrape and frost the ways. It is very tedious work, but cool to know how to do.
en.wikipedia.org/wiki/Hand_scraper

Re:Prior Technology (0)

Anonymous Coward | about 9 months ago | (#45104723)

This is centuries-old hat in all kinds of precision equipment. Just think about the slides on the massive old machine tools.

Similarly, the Empire State Building was just a piece of junk. I mean, the Egyptians did that stuff with the pyramids way before them. They both even used material made out of atoms!

What's crazy here (1)

Anonymous Coward | about 9 months ago | (#45104187)

is that they've made something so small that they have to account for the Casimir force at all.

It's like General Relativity and the GPS satellites. I wonder if they launched the GPS satellites before general relativity was understood, how long would it have taken to figure out why the clocks were running slow?

Re:What's crazy here (0)

Anonymous Coward | about 9 months ago | (#45105929)

i think they (Mil) actually didn't believe it but the scientists/engineers insisted so there was a *switch* to turn relativity corrections on and off on the first satellites !

I heard this on the "infinite monkey cage" a BBC podcast with Brian Cox (physicist) and Robin Ince (comedian). I highly recommend it for an enjoyable way to pass 30 mins and learn something....

Good old LANL (4, Insightful)

Animats (122034) | about 9 months ago | (#45104277)

Ah, Los Alamos. Once it had more great scientists in one place than anywhere else in the world. There was a tradition in the early days that the head of Los Alamos must have a Nobel Prize. That ended in the 1980s when Ronald Reagan put a lawyer in charge.

The US has a strange approach to "national laboratories". The original ones (Los Alamos, Lawerence Livermore, Sandia, Oak Ridge, Savannah River, etc.) were originally all Atomic Energy Commission operations. The Department of Energy got the AEC operations when it was formed. So the US still has a huge nuclear weapons R&D operation, despite the fact that the US hasn't built a new nuclear weapon in decades.

This project sounds more like an excuse for funding basic research than a component needed in a nuclear weapon. EMP shielding isn't that hard. This MEMS device doesn't seem to be a likely choice for the firing switch in a nuclear weapon. Nuclear weapons require a symmetrical implosion squeeze, which is initiated with multiple detonators, all of which have to go off at the same time within 1ns or so. This is done with a setup like a photoflash, but more powerful - a capacitor bank is charged up, and then dumped into thin wire detonators when the discharge switch closes. It's a few KV at a few thousand amps for a nanosecond or so. That discharge switch is what the article probably refers to.

The classic device for that is a krytron. Although using a gas-filled tube is kind of retro, it works. It's probably possible to build some MOSFET device to replace krytrons, as this work at SLAC [fnal.gov] indicates. But a microscopic MEMS device? Too tiny to handle the current.

MEMs in Parallel (1)

Guppy (12314) | about 9 months ago | (#45104855)

But a microscopic MEMS device? Too tiny to handle the current.

Thing about MEMs is, if they're made using semiconductor manufacturing techniques you can make huge numbers of them all at once (unless it's a one-off deviced carved with an electron beam or such). Solid-state power-handling devices can have arrays of millions of mass-produced micro-circuits on an IC, handling macro-sized load in parallel.

Re:Good old LANL (1)

Grog6 (85859) | about 9 months ago | (#45105171)

I'd also agree with the funding thing; that's all I hear about is the constant chasing of funding from people at the lab here.

I'd bet the tech is a more resistant upgrade of the PAL system; from what I've heard, punching in the wrong code a certain number of times renders the bomb useless, until the board is replaced. Unless you're McGuyver, lol.

A mems keylock would be pretty hard to pick... but easy to break. :)

Re:Good old LANL (1)

mbkennel (97636) | about 9 months ago | (#45105391)

"There was a tradition in the early days that the head of Los Alamos must have a Nobel Prize. That ended in the 1980s when Ronald Reagan put a lawyer in charge."

Well, it ended after zero, none of them won a Nobel Prize, but all of them have been PhD's in science. Oppenheimer won the Fermi award.

One of the more recent problems was the transition from light management by the University of California to a commerical contractor (With minority UC involvement) at 10x the price, but an emphasis on compliance and nothing about scientific productivity.

Off switches? (1)

P1h3r1e3d13 (1158845) | about 9 months ago | (#45104279)

could be used as on-off switches for nuclear devices

On-off switches? What exactly is the function of an “off” switch on a nuclear bomb?

Does not help contact surfaces (1)

iotaborg (167569) | about 9 months ago | (#45104301)

Took a look at the article; their conclusion is that a significant reduction of the Casimir force can be achieved using metal gratings, at relatively large separation distances (> 200 nm). Unfortunately this does not solve the problem of high nano-scale adhesion in MEMS devices, because that implies the state is in contact (which is ~1 nm separation, depending on how you define how the atoms of different surfaces "touch" each other). At these small contact distances, the adhesion forces do not reduce with the grating approach. However, using the gratings can slightly reduce the risk of a MEMS component from collapsing when at larger distances from an opposing surface. Essentially, the approach can a device that should not touch an opposing surface, but will not help a device that needs to touch an opposing surface (i.e. a MEMS RF Switch).

And (-1)

Anonymous Coward | about 9 months ago | (#45104341)

Not one single person gave a fuck!

Seriously, what a waste of time, effort, brilliance, and money. Fucking scientific non-alpha bitch ass "yes-men" tools, who buy "the world hates our freedoms" hook line and sinker.

Scientists disgust me.

Re:And (0)

Anonymous Coward | about 9 months ago | (#45104685)

Your troll is too obvious. Try with a more subtle attack on scientists, then you’ll get some bites.

Does this mean warps drives are more plausible? (0)

Anonymous Coward | about 9 months ago | (#45104367)

I think I saw that the cassimir force could be potentially used to form a warp drive of some sort (http://en.wikipedia.org/wiki/Alcubierre_drive). Does this mean that warp drives could be more plausible if we could better control the cassimir forces?

Are you MAD? (0)

Anonymous Coward | about 9 months ago | (#45104455)

Switches that survive a first strike? You mean we're still doing that Kennedy era MAD thing? No wonder FEMA is doing such a shit job with natural disasters...

The Casimir effect is not an exotic force (1)

shadowofwind (1209890) | about 9 months ago | (#45104811)

Its the van der Waals force derived for a bulk material. The rest is marketing.

Re:The Casimir effect is not an exotic force (1)

shadowofwind (1209890) | about 9 months ago | (#45105195)

Also....For a non-flat surface, the force can't be estimated from surface area and distance, it doesn't work like that. The resonances are different depending on the shape. A good estimate of the force of attraction (or repulsion) would have to be derived from first principles, which would be prohibitively difficult for all but the most trivial of geometries. Its not right to say that the reduced force is due to the reduced surface area.

Re:The Casimir effect is not an exotic force (0)

Anonymous Coward | about 9 months ago | (#45105253)

Its the van der Waals force derived for a bulk material. The rest is marketing.

I could be wrong, but I thought the Casimir force was due to quantum effects of particles appearing and disappearing? The van der Waals is from oscillations in charge I believe. Please someone step in here?

Re:The Casimir effect is not an exotic force (1)

shadowofwind (1209890) | about 9 months ago | (#45105647)

The 'virtual particles' are photons. As far as I understand, it is one of several equivalent ways of describing an electromagnetic interaction. There is the familiar inverse-squared electromagnetic force, but the next term in the series has an r^6 in the denominator, so it matters on a much shorter distance.

If only Los alamos were as smart as slashdot, eh? (5, Insightful)

taylorius (221419) | about 9 months ago | (#45104859)

So, to paraphrase quite a few comments on this article:

"Duh, Los alamos are so stupid - less material in contact, less force, just like friction. I can't believe they only just worked that out. I mean DUH, they could've asked me THAT. Oh, and they make nukes. Eurgh, I hate them!"

Really? You seriously think that's all there is to it? I only read the abstract, and it states that the decrease in the Casimir force is far beyond theoretical predictions. But pffth, they probably got that wrong too, right?

I dunno, the misplaced arrogance I read on here sometimes really depresses me.

Re:If only Los alamos were as smart as slashdot, e (0)

dbarclay10 (70443) | about 9 months ago | (#45105415)

Some negative comments might actually be pretty reasonable. That they "only just figured this out" means some combination of the following three things:

1. Nobody tested this until just now, meaning our understanding of the Casimir effect was sufficiently incomplete that nobody should have been writing on the topic with any confidence or authority. A real scientist familiar with the topic probably wouldn't have been; but "real scientists" are sufficiently thin on the ground that you could likely have gone through a doctorate in science and not met one. Teachers in particular, at all levels, seem pretty prone to talking and acting like they're hot shit.

2. Nobody thought to test this until just now, which means that some pretty dumb assumptions were made (they're dumb because they were assumptions and incorrect).

3. Nobody thought to test this until just now, and it's a pretty _obvious_ test too, so either nobody spent any time on it or they were extremely myopic. (Something I've seen in many "scientists"' publications these days; overspecialization to the point of virtual uselessness. They're competent to gather data but not design interesting tests.) I'm only vaguely familiar with our knowledge of the Casimir effect (which is sometimes good!), and I would certainly test all sorts of patterns - on each surface - to figure out how that affects the effect.

Of course this discussion is based on the assumption that what the summary talks about is in the article, which I haven't checked, and that the article faithfully summarizes what's in the paper, which I haven't checked, and that the paper purports that this is new knowledge, which I haven't checked. It's quite possible that what's published in the paper is already well-known.

Re:If only Los alamos were as smart as slashdot, e (2)

shadowofwind (1209890) | about 9 months ago | (#45105567)

The idea that the so-called Casimir force could be made small or negative with a geometry change has been around for a long time. The outcome for a particular geometry is not easy to theoretically predict though.

The summary is bad. For the most part its not about reduction in surface area. So all the comments about how obvious it is that the force should go down with surface area are ignorant.

Almost everything one reads about the Casimir force is based on a misunderstanding of the math tricks used to derive it for parallel plates. Its the van der Waals force, with nothing meaningful going on with 'infinite vacuum energy'. Some scientists are to blame for the confusion, because they exploit the misunderstanding to get funding from ignorant DoE and DoD program managers.

So the summary is misleading, as always, and many of the slashdot comments are off base, as always. The study itself may or may not be stupid or spun in a dishonest manner, I'd have to read the paper and get up to date on other research in the last ten years in order to know. Based on past experience, I would not be surprised either way.

Re:If only Los alamos were as smart as slashdot, e (1)

Born2bwire (977760) | about 9 months ago | (#45106393)

The problem with the Casimir force is that it is difficult to measure experimentally and difficult to calculate theoretically. The research in the past several years has focused on expanding the class of geometries and materials that can be simulated in addition to devising more accurate experiments and methods of fabricating the nanoscale structures.

With Intravaia et. al's paper, they are dealing with a phenomenon that has been predicted theoretically, but has not been verified experimentally. The novelty here would be in being able to construct a periodic nanoscale grating and incorporating it into a measurement device. They also note a deviation in the theoretical force with their plates for large separations. It seems that this comes about due to their use of the Proximity Force Approximation as the kernel in their calculations. The disparate length scales that they are working with in terms of the object size, feature size, and separations are too much for current numerical methods.

Re:If only Los alamos were as smart as slashdot, e (0)

Anonymous Coward | about 9 months ago | (#45105885)

That isn't what occurs to me.

The casimir effect increases proportional to the durction of distance between the plates. Two plates 1 plank unit apart will measure considerably more casimir force than the same 2 plates 1 meter apart. Same two plates, and the same exact force, but the distance between them has changed.

What the scientists are saying here really is a DUH type statement. We have known for many years now about this relationship of casimir effect's force with distance between the plates. By making part of the plate further away, you reduce the force proportionally. The same is true of the idea behind a space elevator, (where gravitational attraction of the tethered station is less than at the surface of the earth, because of the higher orbit, combined with centrifugal forces), or with a needle stuck to a magnet. The magnetic flux measured at the tip of that needle will be significantly less than if both magnets were directly that close to each other.

It really is a no brainer.

The more interesting thing is that they have the degree of manufacturng sophistication to create complex structures to make use of that.

The actual headline is itself misleading as well. They haven't actually found a way to block the casimir effect. They just mitigated its effects in a simple way. (I would be much happier if they HAD actually found a way to silence the casimir effect, because that alone would make warp travel possible, because it means creating perfectly flat and smooth spacetime. The alcubiere metric requires a gradient with negative energy. Silencing the foamy nature of spacetime would create that gradient, and is what would need to happen to silence the casimir effect.)

Compare it this way:

"Scientists discover way to turn off permanent magnets! Just move them really far apart!"

Vs the much more accurate and less sensational:

"Scientists mitigate magnetic force of attraction by keeping magnetic components further apart in devices plagued by magnetic clamping."

*Note for pedants who can't handle that analogies are by necessity not exact fits:
Yes, I KNOW that the casimir effect is not carried by photons, and is not anything at all like the strong EM force, other than being impacted by distances. The analogy is being given because both forces fall off sharply as distance increases, and because the strong EM force is better understood by most people, and can thus explain the brokenness of the headline. Yes, I know the casimir effect is created by there being more virtual particle interactions outside the plate gap than inside, and that it is more a composite effect than a fundamental force. That is not important to the analogy. What is: apparent attraction; gets weaker with distance; always present; Not actually turned off by this technique. So just chill. This is an "apples are like oranges because the are both fruit." It is NOT intended to be tortured into saying "apples = Oranges". No, this does not mean you get to play grammar nazi either. The use of incorrect spelling or grammar is inconsequential, and a complete non-sequitor. Obcessing over any such thing only indicates your own mental handicap, and is not grounds to disqualify the analogy, nor to character assasinate the author.(no, spelling and gramatical mistakes are not indicators of a lacking intellect. Disregarding proper rigor in keeping correlation and causation apart by insisting on such a relation, most certainly is, however. Insisting that there is a causal relationship where there is none, only shows this deficiency. It proves nothing else.) I take no pleasure putting a fucking wall of text here just to tell you to grow the fuck up and be sensible. You should fucking know better by now. No, this does not mean you get to derail the thread to talk about this invective dripping reminder to you to not be a dickweed; it's here to tell you to keep any such reaction to yourself, because no-one else fucking cares. Again, I am disturbed that such reactions happen ofetn enough here to warrant putting this message. Analogies are by necessity IMPERFECT. Deal with it. If you are not such a pedant, and are not driven to do any of the above things, then great; this message is not for you, and you should ignore it completely.

Re:If only Los alamos were as smart as slashdot, e (1)

RedBear (207369) | about 9 months ago | (#45106679)

So, to paraphrase quite a few comments on this article:

"Duh, Los alamos are so stupid - less material in contact, less force, just like friction. I can't believe they only just worked that out. I mean DUH, they could've asked me THAT. Oh, and they make nukes. Eurgh, I hate them!"

Really? You seriously think that's all there is to it? I only read the abstract, and it states that the decrease in the Casimir force is far beyond theoretical predictions. But pffth, they probably got that wrong too, right?

I dunno, the misplaced arrogance I read on here sometimes really depresses me.

There's arrogance, but then there's also the fact that this really does seem perfectly intuitive. If your surfaces have a tendency to stick to one another due to some kind of oddball "force" not quite the same as but similar to the static friction force, how is it not obvious that it might be helpful to reduce the amount of surface area that comes together between the two surfaces? After all, it works well with static friction.

I'm thinking this came out because A) they found a good way to create a micro- or nano-scale surface with sufficiently reduced area, and B) the positive result seems to significantly exceed the predicted effect, and they don't know why. That's why it's interesting. Not because the underlying concept is an amazing new idea. I'll bet the idea has been around for a long time, which is what prompted them to try to take the steps that created this result.

I don't think there's any need to be so offended by peoples' intuitive response in this particular case. They're just reacting to an article and summary that makes it seem like the simple part if the story (the idea of reducing surface area in contact) is a new, breakthrough idea when it really isn't, instead of emphasizing the parts of the story that are actually new and interesting (the actual results that exceed predictions).

Brilliant! (1)

msauve (701917) | about 9 months ago | (#45105545)

the Casimir effect â" an exotic force that pushes metallic sheets together when they are separated by tiny distances.

So, the solution is to make one of them not-a-sheet!

This isn't "suppressing the Casimir force," it's avoiding it.

More junk on Slashdot (0)

Anonymous Coward | about 9 months ago | (#45105679)

All major nations have known how to shield their equipment from EMP for decades. MEM devices are NOT invulnerable to EMP by design, because EMP is an inductive issue, potentially placing damaging levels of energy into any delicate metal construct. Why do we need some no-nothing cretin drawing conclusions from scientific/engineering discoveries that he/she clearly does NOT understand?

The summary is utter GARBAGE. One glance at the paper shows the significance of the discovery is that the Casimir effect is reduced far more than the modified physical geometry of the metal sheets would suggest if current understanding is true. So the paper is SIGNIFICANT because our current predictive model for the Casimir effect has been shown to be WRONG in certain reproducible circumstances.

This is how science works. You create predictive models (which are NEVER the same as reality- hence the word 'model'), and ONLY if the predictive model proves accurate (the predictive models for man-made climate change have all FAILED), do you call it any form of scientific principle. Then, later, if you find cases where the predictions of the model are poor or just wrong, you attempt to improve or replace the model with one that works better.

Significant man-made climate change is junk science because the predictive models fail every mathematical test (and saying "yeah, we've been wrong fifty times in a row, but this next model will prove correct in 50 years time, just you wait and see" is NOT science).

Science is NOT paranoia. Science is NOT popular opinion (even the popular OPINION of a large group of very low quality or dishonest scientists). Science is NOT religious ideas dressed as science (like the 'big bang' analogue for the 'Garden of Eden', or the nonsense of free-will somehow wobbling out of quantum theory). Science is NOT whatever the will of your current masters says it is via their mainstream media outlets.

In truth, the discipline and rigours of science and the scientific method are far too dull for most science junkies, so the more scientifically-minded sheeple are constantly fed SF as science. Hence the nonsense about EMP in the summary.

PAL (1)

Maj Variola (2934803) | about 9 months ago | (#45105739)

Look up PAL. I think Bellovin is the CS expert.

False alarm (1)

paiute (550198) | about 9 months ago | (#45107053)

I got excited when I read the title, as suppression of the Casimir effect implies some way to manipulate virtual particles and would be required some breakthrough in our understanding of profound processes. But the article means that they discovered a way to minimize the force the effect applies, not suppress the force itself.
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