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Quantum-Tunneling Electrons Could Make Semiconductors Obsolete
Nerval's Lobster writes "The powerful, reliable combination of transistors and semiconductors in computer processors could give way to systems built on the way electrons misbehave, all of it contained in circuits that warp even the most basic rules of physics. Rather than relying on a predictable flow of electrons that appear to know whether they are particles or waves, the new approach depends on quantum tunneling, in which electrons given the right incentive can travel faster than light, appear to arrive at a new location before having left the old one, and pass straight through barriers that should be able to hold them back. Quantum tunneling is one of a series of quantum-mechanics-related techniques being developed as possible replacements for transistors embedded in semiconducting materials such as silicon. Unlike traditional transistors, circuits built by creating pathways for electrons to travel across a bed of nanotubes are not limited by any size restriction relevant to current manufacturing methods, require far less power than even the tiniest transistors, and do not give off heat or leak electricity as waste products, according to Yoke Khin Yap of Michigan Technological University, lead author of a paper describing the technique, which was published in the journal Advanced Materials last week."
You mean the 1950s are back? Tunnel diodes were supposed to rule the world back then too! How exciting!
Except, you know, space itself. Period.
Phase velocity exceeds c, not group velocity. If you guys wanna prove Einstein wrong, you're gonna have to work a little harder.
Dear OP, transistors are f****** semiconductors! The rest of the article is at best starry-eyed fantasy.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
It does. Tunneling is instantaneous. It may even be able to transfer information, but the jury is still out on that and classical quantum mechanics says it cannot. If it can, then it can transfer information without time delay, but only over short distances and with a large energy investments that almost completely goes into losses. That way, it would basically never happen in nature and it cannot go over significant distances.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Wrong. Tunneling is instantaneous and it is a well-established mechanism. It has severe distance limits and the question is whether it can transfer information FTL.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Look, it's not a religion, you were taught a set of beliefs and you refuse to question them. Why?
period.
I'd like to think that some day we'll figure out how to make things go faster than light. But we haven't done that yet, and it would be big news if we had. Describing it that way in the summary is simply wrong.
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
Tunneling is instantaneous. A tunneling electron (for example) jumps from one position to another. It does not cross the intermediate space, so you can say it actually does not go FTL, because it does not "travel" in a very real sense. Tunneling is a very well established effect. For example in Zener-Diodes with 5.6V about half of the noise produced is tunneling, and about half is thermal.
So, sorry, you are wrong. What is unclear though is whether tunneling can carry information. There is some indication that it can, but it would probably be severely distance limited (read: centimeters to meters at best) and hence not play any role in the larger scheme of things.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Found this on wikipedia:
http://en.wikipedia.org/wiki/Faster-than-light#Faster_light_.28Casimir_vacuum_and_quantum_tunnelling.29
Faster light (Casimir vacuum and quantum tunnelling)
Raymond Y. Chiao was first to measure the quantum tunnelling time, which was found to be between 1.5 to 1.7 times the speed of light.
Einstein's equations of special relativity postulate that the speed of light in a vacuum is invariant in inertial frames. That is, it will be the same from any frame of reference moving at a constant speed. The equations do not specify any particular value for the speed of the light, which is an experimentally determined quantity for a fixed unit of length. Since 1983, the SI unit of length (the meter) has been defined using the speed of light.
The experimental determination has been made in vacuum. However, the vacuum we know is not the only possible vacuum which can exist. The vacuum has energy associated with it, unsurprisingly called the vacuum energy. This vacuum energy can perhaps be changed in certain cases.[38] When vacuum energy is lowered, light itself has been predicted to go faster than the standard value c.
"I think this line is mostly filler"
He wants his junction back
Some drink at the fountain of knowledge. Others just gargle.
Can't the slashdot editors be more active with their copy? Nothing goes faster than light. period.
Correction: no information travels faster than light. It is easy to imagine a system which looks like something is moving faster than light: shine a bright enough torch on the moon. If you move the torch fast enough it will look like the spot on the Moon is moving faster than light. This is perfectly fine because there is no way to change the where the beam moves if you happen to be where the beam is pointing at a particular time i.e. no information flows between one spot and the next because everything is under the control of the torch wielder back on earth.
In QM tunnelling the transmission speed of information is always below the speed fo light and so there is no problem (if you know secondary [high] school physics this is like the difference between phase velocity and group velocity of a wave in a wave guide). However where the editors messed up is the statement:
...in circuits that warp even the most basic rules of physics.
These circuit DO NOT warp the basic rules of physics. Quantum mechanics IS a "basic rule of physics" - it is certainly counterintuitive but it is a fundamental rule of physics.
And yet virtually every major advancement in science over the ages has been directly contradictory of the current wisdom. Real scientists don't hold religiously to the belief that they're right, they actively try to prove themselves wrong and take great joy whenever they succeed.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
My corollary to Betteridge's law of headlines: If a title has "could" in it, you can replace it with "probably won't".
Citation please. I've studied the history of science and you are speaking bullshit. I think you have quite the belief you need to challenge, and you might want to reflect on your own hypocrisy. Are you thinking, for example that Einstein disproved Newton or that quantum mechanics disproved classical physics? Neither of these occurred. Both of these theories simply amplified the previous theory and explained phenomena beyond the previous range of observations. And not surprisingly, relativity and quantum mechanics become classical physics at normal resolutions.
You've probably repeated that line about noble scientists who fought the system to get their theory through a hundred times, right? The reality is that for the last several centuries, it has just been data that has driven scientists. Even something as revolutionary and contradictory as evolutionary wasn't driven out of a desire to fight against current wisdom and have an open mind. It was simply due to finding the right data. The Big Bang? Data again. Plate tectonics? Data yet again. Solar nucleosynthesis? Data still.
No, you pretty much made that up. Or you're defining "major advancement" such that it cannot be a major advancement unless it's contradictory to current wisdom.
Regardless, the summary is clearly wrong, because there has been no breakthrough that lets information travel faster than light. If there were, we probably wouldn't be talking about transistors, we'd be talking about that breakthrough.
And the scientific wisdom is almost always right -- that's why it's so impressive when it's wrong. You absolutely should treat any claim of FTL with the same extreme skepticism as hollow Earthism. Especially since it is relatively easy to show (eg. to those with approx. an undergraduate education in a related field, or a precocious high-schooler) that FTL implies the possibility of backward time travel, barring a few really, really conceptually unlikely and unsatisfying scenarios.
In my experience, this notion of "major scientific* advances are always people who don't accept conventional wisdom" only ever seems to come up in discussions about the speed of light, in discussions about global warming, and in discussions about Young Earth Creationism. I might be forgetting a couple. But I think the unifying feature is that people really, really *want* the truth to be different from what all the evidence points to, because that would be so awesome. Well, the awesomeness is debatable in terms of YEC, but it would be really cool if global climate change were something that'll sort itself out without us, or if the speed of light turned out to be just a trivial matter and all the stupid scientists were just dribbling their lips with their fingers instead of pressing harder on the gas pedal. It's just not what anything points to and we should demand extraordinary evidence of claims to the contrary just like we would demand extraordinary evidence of a machine that resurrects people hundreds of years dead with their memories intact. Okay, maybe that latter claim is even more unlikely to be true -- but then again the extraordinary evidence should be a bit easier to produce if it is true, so I think that balances.
*For political advances people say this all the time. It's often how they defend people like Stallman for being an asshole, or Gates or Jobs or Torvalds etc..
What is unclear though is whether tunneling can carry information. There is some indication that it can...
No that is clear - it cannot. If it could, and if there was any indication that it could, it would be direct evidence of the violation of causality. This is a "Big Thing" at ANY scale because all I have to do is find an intertial frame where the receipt of the information precedes its reception and then stop the information being transmitted. Having this restricted to a distance of a few cm just makes the resulting paradox less entertaining, but just as implausible, as the ones you see on Star Trek.
Usually Nerval's Lobster promotes self-described tech-writer-gun-for-hire/Slashdot "editor" Nick Kolakowski's work. In this case, the author of the Slashdot content is Kevin Fogarty, who recently brought us such gems as thinly-disguised press releases for Cumulus Networks, Enterasys, and Heavy Reading, all of which use curiously-similar ambiguous stock photos from Shutterstock... My guess: the people behind the article (which we can't read) paid for it to be summarized and posted on Slashdot so they could pursue further funding by claiming their work has been "featured" (legitimized) on Slashdot.
This has been going on for some time now with Nerval's Lobster. Many people have learned not to feed the troll (don't post comments on Nerval's Lobster submissions), but if you're just joining us, welcome! And try not to feed the troll.
Reread the history of your profession. You are astoundingly wrong, though I'll admit the early examples are more impressive by dint of resulting in imprisonment, torture, and such. Even today though it's not difficult to find classical and M theorist zealots calling each other crackpots or worse.
I'm not taking issue with the FTL wrongness in the article. I'm taking issue with those who believe something to be Truth rather than theory. That is a hallmark of religion not science. Theory means "This is true as far as I can tell. If you can prove otherwise, have at it."
As for my definition, nobody ever became famous for making steady, incremental advancement in their field. Greatness comes from turning things on their ear and thinking the thoughts that your peers would never even consider.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
The reason why this is not a problem is because the electron does not actually travel from one point to the other, which would mean there were intermediary points of existence along the way. This is a quantum movement. The electron stops probably being at one place and becomes more probably in another place. It never was in any “place” to start with since placeness is not a quality of an lepton in motion.. Nevertheless, the event of the movement from one probability to the next is not really time measurable as an event, only as a measured effect.
But what if you have a mile long pole and correlate it's movements into a form of communication. As soon as you move the pole on one end it would instantaneously move on the other for instantaneous communication.
Nope. The motion propagates to the far end at the speed of sound in the pole - much faster than sound in air, but glacial compared to light in vacuum.
Don't bother looking for an unobtanium with near-infinite stiffness and an internal speed of sound faster than light-in-vacuum. The motion at one end encodes information about what is happening at that end and that information is propagated down the pole by interactions between the pole's component particles, interactions that all are no faster than the speed of light.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Bob Widlar. Luther Burbank. George Washington Carver.
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Wow, just imagine a beowulf cluster of whatever this article is about...
When I was young kid, in the early 1960's, I visited a ham radio operator a bunch of times. Cool radios, etc. He taught me some key things about tubes, started a long slide into technology that still hasn't stopped. I asked him about transistors. He looked at me somewhat askance and said "yeah, "I heard about them things. Tubes, son. I know tubes." And went back to teaching me about tubes, and resonance, and etc. Outside of his place, I hooked into an NRI electronics course, and spent a summer sucking that down, while running to my older friend Tony to help me with the math. NRI was teaching tubes then too, but they had an excellent section on transistors, and so I grew comfortable with them just as they were becoming interesting and more widely used. Tubes, except for certain specific jobs, just aren't used much now as we all know, and I've always been grateful for my luck in terms of timing; a few years earlier, and I'd have been looking askance at transistors myself. But instead, I've been comfortable with semiconductors right up until they got too small for me to handle (surface mount, trembling hands, etc.) And I know tubes.
The idea that another revolution of similar importance may happen in my lifetime...
Damn. I just feel like one amazingly lucky fellow. :) Now, will I be able to grasp the tech if it makes it to market? That, as they say, remains to be seen. Getting older doesn't mean you're without a clue. It just means you no longer always know where you put them.
I've fallen off your lawn, and I can't get up.
I know a few famous physicists that would disagree with you on your argument that space is "nothing" and isn't "something." "Empty space" isn't actually empty at all, and space-time itself has lots of intrinsic properties. I believe there's a NOVA special on the subject available online for free if you'd like to investigate.
For instance, if you were to start spinning in empty space and no other matter or light in the universe existed (yet you were still somehow alive), you would still feel your arms being pulled outward due to your spinning motion -- even though you had no point of reference to even know that you were spinning at all. You'd still be spinning in relation to the invisible framework of space-time.
On an unrelated note, there is a controversial quantum theory that light speed in empty space is not a finite speed, but an average speed. Further, an expansion on that same theory is that photons travel at infinite speed, but in the medium of empty space, they randomly hit virtual particles which absorb and re-emit them which is what slows them down to what we measure as light speed. The rate of hitting virtual particles can be predicted statistically and works out to be in line with what one would expect in order to get the current measurement for light speed, but it could all be wishful thinking and tinkering with math.
Because
1) No one's managed to get relativity and quantum effects to line up with each other yet.
2) Relativity doesn't ban traveling faster than light, it bans accelerating to the speed of light.
Wouldn't that disagree with the fact that the measured speed of light in vacuum, by any observer traveling at any speed, is the same? If the speed of light is just a matter of light being slowed down by virtual particles, there's no reason why your own speed wouldn't be added to or subtracted from the speed of a particular beam of light. Relativity would just go right out the window, we're back to aether theory.
Wrong. Dirac did. And it led him to the prediction of antimatter. And all quantum field theories are relativistic quantum mechanics.
What hasn't yet been managed is to unite general relativity and quantum mechanics. However that's irrelevant for the FTL tunneling question because the speed of light limit is a property of special relativity, which has completely and fruitfully been united with quantum mechanics a long time ago.
Relativity tells us that if we could travel faster than light, then we could also violate causality. So unless you are willing to give up causality, relativity indeed does ban travelling faster than light.
Regardless, the summary is clearly wrong, because there has been no breakthrough that lets information travel faster than light. If there were, we probably wouldn't be talking about transistors, we'd be talking about that breakthrough.
I guess you are the wrong one here. Read http://en.wikipedia.org/wiki/Faster-than-light#Faster_light_.28Casimir_vacuum_and_quantum_tunnelling.29
Faster than light expansion is just a mathematical oddity caused by the use of a particular coordinate system. Not that there's anything wrong with it, just that nobody ever seems to explain it properly.
Local distances and times are easy to measure objectively using clocks and measuring rods, but the definition is not so clear and unambiguous anymore when you're talking about large distances in the expanding universe. Different metrics exist, defining distances, times and speeds in a different way, yielding wildly different values while giving the same tangible results for any actual event. I will give you two ways of looking at the universe: the first conserves the speed of light but looks very weird, while the other looks more normal but does not respect Special Relativity. Under General Relativity, which allows a wider range of metrics, both models are perfectly valid and consistent. I will disregard the effects of gravity, but otherwise it should be a pretty accurate description, certainly enough to explain what "space itself" really means.
If you define distances, times and speeds using the common sense definitions from Special Relativity (using beams of light to measure distances, always assuming a constant speed of light), distant galaxies are traveling away from us at high speeds (but less than the speed of light) and therefore time passes more slowly for them. Since this has been the case ever since the big bang, they are younger than us at this point in time. They don't just look younger because we had to wait for their light to get here, but they really are younger "right now" even if we take the traveling time of light into account. If we could "look" at them directly without having to wait for the light to get here, like we could do in a mathematical model, we would "see" the universe getting younger and younger, and clocks ticking ever more slowly, the further out we "look" in our expanding universe. At a distance of c times the age of the universe, the big bang is happening "right now". This gives the universe a finite size (assuming nothing existed before the big bang) but it does contain an infinite amount of matter thanks to Lorentz contraction. Everything near the boundary is squished in the direction of the expansion so that an infinite amount of stuff fits in this finite amount of space.
This metric is a bit cumbersome because it gives us a special position at the center of the universe while in fact there's nothing special about our position at all. Some other, distant civilisation (in the distant future according to the above metric) will actually say that we don't exist yet and our galaxy is much younger than theirs, "now". (Using their definition of "now"). That's just the classic twin paradox, nothing really wrong with that, but it does make our point of view a bit subjective.
So cosmologists came up with a better metric, the cosmological model: they define time as whatever is measured by local clocks that are traveling at the same speed as the average galaxy in that area (the expansion speed vector), undoing time dilation due to the expansion and thereby making the whole universe the same age. Local distances are defined in such a way that objects look pretty much the same size everywhere (no Lorentz contraction due to expansion speed), which can be achieved by defining distances in function of a constant speed of light relative to the expanding universe. So in effect we stretched the universe and sped it up, just by using a different definition of "now" and by measuring distances differently. With this model, the universe looks nicely homogenous and truly infinite, making many calculations a lot easier. There's no longer anything special about our location.
But because we changed our definitions of space and time, some of the old assumptions from special relativity are no longer valid. Things can and do fly away from us at speeds well in excess of the speed of light simply because we are defining their speed differently. But the light from those places will ne
Its not. Its a stupid laymen interpretation of tunneling. Try and sent information and it doesn't work because of the probabilistic nature of tunneling.
If information wants to be free, why does my internet connection cost so much?
Since Einstein hasn't been proven right
Probably because you can never prove a scientific theory right. You can however repeatedly fail to prove it wrong, and that's been done many many times w/ Einstein's theories.
He said that rigid poles don't exist. They are in fact atoms which interact more or less like a chain of car suspension systems. Imagine your pole as a line of metal balls chained by a spring. When you push a ball at one end, you get a delay until it moves at the other end. With a long enought pole you need a distributed parameters model to solve the math. (The equivalent issue happens with an electric transmission line). The end result is the same as with an electric transmission line.
Or maybe we're in a "circles within circles" period again like we were for the orbiting of the planets. Long ago, it was believed that everything orbited the Earth in perfect circles. When the data didn't line up, additional circles were added to the orbits to make the theory fit the data. It worked to a point, but it was a hideous mess. Making the Sun the center of the solar system and ditching the perfect circles cleaned up the theory a lot. Perhaps one day we'll come up with a theory of the Universe that will make our current theories look like the "circles within circles" idea. That theory might allow FTL travel in a manner that seems simple to future humanity but is as understandable to us as computers would be to an ancient Roman.
My sci-fi novel, Ghost Thief, is now available from Amazon.com.
Why would it?
The atoms in the material are not "conjoined", there are no solid things pushing against each other. They are point forces that act upon each other. The closer they are, the more they will "push" away the other, like atomic springs. But they aren't touching to begin with, merely held in a nice "valley" of forces where they can rest naturally in a particular material. In a dense material, that valley is probably closer to other atoms than in a less dense one but at no point are the protons from one atom hitting those of another (or else you could start a nuclear reaction by banging two things together or putting Uranium under pressure by - say - burying it under a million tons of rock).
Shoving one end of a pole six feet long might only take some infinitesimal fraction of a second to see the effect on another but it doesn't mean it was instantaneous.
Imagine you had a box full of rubber balls. Now imagine you push the bottom of the box up. Are you suggesting that the top rubber ball responds instantly at the same rate at the force at the bottom? Or that the force you applied compresses the bonds between atoms that push each other away, and so that pushes on the next, and that, eventually, when it reaches a point where it can't be compressed any more, pushes on the next and on the next and so on. It's a physical chain of events, not magic.
Then, are you suggesting that happens instantly in any material that isn't a material at absolute zero of the highest possibly achievable density? Because Brownian motions mean that the atoms are pushing off each other all the time but still they "react" instantaneously? No.
Think of a tube of Smarties (a small tube of sweets). When you push the bottom of it the top one drops out but that isn't "movement" of that one across the whole distance of the tube. And it's not instantaneous.
And if you scaled it up, shoved it with a huge stick and filmed it in slow motion, are you suggesting that you would not see the smarties compress and distort and fight the force for a fraction of a second before they poured out of the other end? Now think of atoms as smarties and see what happens.
By applying a force, no matter how small, to an solid object you are STILL compressing that object's atoms to be in closer proximity But they are NOT touching (think about electron orbitals, etc. - if they could touch you have MUCH bigger problems, like electrons being trapped and held still). The "movement" of that object as a whole is the resulting actions of those atoms while still caught within the atomic bonds that they are.
The atom is also mostly vacuum. The forces within it are what make you think it's "solid". It's not. Those forces can be added to from any direction and the result is NOT that the molecules of atoms move in that direction automatically. It might compress, bringing the atoms closer, but then they fight each other back. Hence we *can* turn carbon into diamonds when the carbon atoms are compressed and forced into a certain state. And we can "break" an atom by firing something and powerful direct at its nucleus.
The atom is not solid. As a result, no solid material is "solid". They can all be compressed with the application of force except for a material at the maximum possible density at absolute zero (the heat is enough to make the material have a force to fight back). As they can be compressed a lot, they can also be compressed a tiny, infinitesimal amount on a sliding scale. And the gaps between them are not solid-steel-girders of reinforcement but the forces at play (similar to a magnetised ball-bearing near another, oppositely-magnetised ball-bearing) that can be overcome up to a point.
And by pushing on the bottom of a pole, you are putting an atom with a certain force near another atom with another force and pushing them into proximity. If it's easier for that atom of the pole to push you back, the object doesn't move and your hand stops. If it's not, it will push it's neighbour the
The "signal" represented is psi squared, or the probability of finding the particle at a particular position in space. The particle can exist anywhere under that curve. With an energetic enough particle or a small enough potential barrier, the particle can predictable tunnel across the barrier, which is what the video is showing (The video is showing the probability of the particle tunneling).
The tunneling process itself depends on collapsing the wavefunction and the particle interacting with some other physical process. Collapsing the wavefunction is an instantaneous "event". Any time the probability function spans both sides of the potential barrier, there is a chance that the particle can "exist" on either side of the barrier. In this case, it never crossed the barrier, because it always had a chance of existing on both sides of it.
If you want a vision of the future, imagine a youtube comments section scrolling - forever.
As for my definition, nobody ever became famous for making steady, incremental advancement in their field.
So the real argument is about the word "incremental"? Einstein did not discover the Lorentz invariant, he did not discover the photoelectric effect, he did not discover the black-body quantization of Max Planck, and Planck did not discover the idea of quantization... Everything has been an incremental advance for various values of "incremental".