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Data Transfer Has A Speed Limit
ChrisHanel writes "Yahoo News is reporting that despite the infinite climb data speeds seem to be making, scientists at Stanford say we'll eventually hit a barrier due to the inability to keep the data stable after a certain transfer speed. But no worries just yet; the watermark they've set is still 1,000 times faster than what we have now." Apparently: "The scientists confirmed this problem by firing up the particle accelerator at Stanford University and blasting electrons at a piece of the magnetic material used to store computer data."
This kind of thing crops up now and again in lots of fields. It's basically the same problem that keeps being predicted with our Interstate Highway system. There's a safe limit as to the speed that we can have cars travelling, and if the highways fill up, bumper to bumper all moving at that speed, we've reached capacity.
The most obvious solution there is the same as the obvious solution here: Add more lanes. If you have thirty-two lanes of traffic instead of one, you've increased your capacity roughly 32 times. Same situation here: Transmit 32 bits in parallel (simultaneously) down distinct channels, rather than in serial (one at a time).
Just as building more lanes is expensive, here the expense comes in multiplying all of the necessary hardware to handle wider data busses for as far down the path as necessary to deal with more data in parallel. Right now, we've got parallel busses inside our PCs, but the bits often end up serialized at some point inside our processors, down at the microcode level. All of these bottlenecks need to be categorized and eliminated to overcome such a theoretical data transfer limit. It will be neither easy nor inexpensive, especially when we decide we need to send and process, say, 2048 bits in parallel in order to meet our data processing needs. At some point, it becomes more economical to separate things on a higher level (add more processors, or add more PCs), similar to building additional highways rather than just adding lanes.
It's hard for thee to kick against the pricks.
(very slightly off topic... sorry.) I attended a physics colloquium the other week in which a professor from Duke was presenting the results of his research into the question of whether information could be sent faster than light through the various ways of coaxing wave speeds to be faster than c in anomalously dispersive media. If you concoct a medium in which the index of refraction decreases as the wavelength of light increases, the "group velocity", or the speed at which pulses propagate, can be made to be faster than c. The "phase velocity", or the velocity at which each frequency of light propagates, is still less than c, but the pulse that each frequency is a part of is going faster than light. The problem is that for the most part, the shape of a wave is pretty deterministic once you've seen a fairly small sample of the waveform. So recieving just the first few microseconds / nanoseconds / etc. of the pulse tells you everything about all of the frequencies which make it up. But he added a nondeterministic part to the signal he sent (through this anomalously dispersive media), changing the shape of the pulse midstream depending on whether he was sending a "1" or a "0". He then timed how long it took before his detector could tell whether the incoming pulse was a "1" or a "0", and determined that despite the media appearing to emit the pulse before it recieved the pulse, his detector still could not differentiate between a "1" and a "0" faster than the speed of light. So Einstein (and Maxwell) continues to be vindicated, and information cannot possibly travel faster than the speed of light.
You probually do have a particle accelerator lying around. Your CRT accelerates electrons onto the screen. If you consider X-rays and microwaves as particles, you probually heat your food with one. Your TV produces X-rays. If you have an old smoke detector, you can probually make a quick and dirty Alpha-gun. (Americium decays ejecting alpha particles).
Although, if you want a High-Power accelerator, that's a different matter and it would be very interesting to do it. Hmm... Use your own power generator? I doubt the power company will be able to supply you TeV's through your power outlet, but then you would need your own Nuclear reactor to do that.
If you can make even a GeV accelerator, that would be impressive. If anyone's heard of such a back-yard project, let me know.
Never let your sense of morals prevent you from doing what's right. --Isaac Asimov