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Comment I think Samsung is just patent trolling (Score 1) 52

The difficult part of making a holographic display is the "transmissive light spatial modulator", as its referred to in the patent application. Since the patent tries to cover any conceivable device that would have this functionality, it is unlikely that they know how to make one themselves. Most of the main "innovations" are things which I realized after a couple of days thought on the subject (with just an undergraduate physics degree and no professional experience), so I can only imagine that they are so obvious to an actual expert in the field that they are not even worth mentioning.

Comment not the time travel you are thinking of (Score 1) 268

A particle traveling forwards in time is (before this research, anyway) mathematically identical to an anti-particle traveling backwards in the time dimension. Historically, we've assumed that you could reverse all the velocities of the particles in a system and it would behave exactly as if time was going in the opposite direction. Showing that this is no longer strictly true does not necessarily mean that the universe doesn't consist of a 4D chunk of space-time which you could travel though using magical technology and make changes which propagate forward according to rules that are just vague enough to prevent infinite recursion. However, not too many people know how significant an exception to time-symmetry is, so I guess they have to make do with the closest widely understood concept. I wouldn't find this so annoying if it weren't for the fact that there are many fields of science which I don't know enough about to know to what extent they are getting creative with the press releases.

Comment beware of unexpected expenses (Score 1) 211

This is just as much a cautionary tale for those thinking of RUNNING a crowd-funded project as it is for people buying into one. I wrote the libraries for an arduino-based robot where the engineering wasn't too complicated (an accelerometer, gyro, piezo, IR sensing/com, charging circuit, 2 motor PWM circuits, & half a dozen neopixel LEDs), and there were already 4 fully functional prototypes before the Kickstarter even began. However, it still ended up costing at least 50% more than expected to manufacture each unit.

Comment they just have to change their business model (Score 1) 533

I don't have much to add myself, but a friend who has worked closely with utility companies (both ones who primarily produce and which mostly distribute power) and he said there wasn't any reason they couldn't make just as much money from people's personal solar (or other) generators, but that they would have to change their business model. He said it wasn't likely unless they were paid to (via government incentives) or if the existing companies went out of business and were replaced by new ones that were prepared to deal with the changing marketplace.

Comment good for science, not so good for privacy (Score 1) 91

The most immediate effect is to make it easier to investigate some of the more esoteric predictions of QM. With this and similar components you could also potentially build an optical general purpose quantum computer (the ones on the market are not general purpose), which would finally make things like exact computational chemistry possible, but unfortunately would also make public key encryption obsolete (though AES will only have to double in key length). It could also be used to make quantum cryptography (which isn't actually necessary unless we have quantum computers, though I sometimes wonder if someone like the NSA has already has already put together spectacularly bulky and expensive versions with current technology). As pointed out in another post, we would also need to upgrade our fiber optic communication hardware so for a while we might be in a situation where only large corporate and government interests will be able to afford it.

Comment Wish the US had this sort of policy (Score 1) 67

First China comes out with a plan to boost their higher education & research, then their solar power industry, space program, and now robotics. Meanwhile, OUR government's plans seem to mainly consist of which country to invade next (which wouldn't be so bad if we actually got the cheap oil the voters were implicitly promised) while protecting and bailing out incompetent and/or obsolete industries.

Comment Tentative summary (Score 1) 150

That's pretty much the way I understand it. This is exciting enough so that I am going to read through the full published article. If true (can't wait for others to try to reproduce it), then one of the stranger things implied is that while in a superposition of different positions, other particles feel the electron's field not just in proportion to 1/r^2 but also in proportion to its probability amplitude of being in that particular position at all. It also seems to provide a way around the "decoherence means you can't test for observation anyway" excuse for ignoring the weirder parts of QM.

Comment Is this a troll article? (Score 1) 121

As one person commented when the last version of this went around, the sound card hardware or driver would have to have something like a TCP/IP stack built in to the microphone input. In other words, the only way a computer would be vulnerable is if it already has an ultrasonic communication feature installed. The only way I can see this happening is possibly at the behest of a certain agency which has a history of covertly installing security vulnerabilities, but they would probably just put it in the WiFi.

Comment Simple solution: 1 second increments (Score 1) 246

Have the servers record all trading requests for the last 1000ms in encrypted form, then do all the trades at once. There are almost no real-world economic factors (ie sales, storms, new patents, employees hired/fired, etc.) that happen even this fast, so the only people who would complain are those who make money specifically from high speed trading games.

Comment how can they use the stolen username (Score 1) 448

Maybe I just don't know enough about how law works in this area, but it seems like everyone now knows that "@N" is stolen. What can the hacker do except post "hey, I'm the anonymous person who stole this account"? Is it legal to buy a stolen Twitter account? Can't he just contact the company and get it back? If regular identity theft worked this way then you'd get police saying "sorry sir, but he has your name, SS, and DOB, so he can now use your identity in any way he wants"

Comment he does have a point, but maybe goes too far (Score 1) 312

I agree that mathematicians may become imprinted on standard deviation and forget that it is only used because it is easier to work with than average absolute deviation (ex: the derivative of x^2 is continuous, unlike abs(x)), and that less technically inclined readers might not realize there is a difference. However, they ARE usually pretty close (I don't have a reference, but I once ran a simulation comparing the 2 using random data with a Gaussian distribution and the curves matched exactly), and its harder to find exact solutions with average absolute deviation. On the other hand, it wouldn't hurt to use "MAD" occasionally on a data set to make sure that the standard deviation gives results that are meaningful as a measure of "deviation".

Comment Using labview compiler for FPGA (Score 1) 365

Haven't done this myself, but you can evidently run Labview programs ("virtual instruments") on some FPGA chips. You'd have a good estimate (plus an actual digital circuit) if you translated your code to labview (I believe the actual language is called "G") and found a copy of the add-on which turns this into verilog. -- Dustin

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