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Quantum Physics Just Got Less Complicated

barlevg Re:Pilot Wave (170 comments)

As I understand it, Pilot Wave theory is a hidden variable theory, and Bell's Theorem says you can have hidden variables or locality (meaning no action-at-a-distance), but you can't have both, and most physicists really don't like the idea of giving up locality.

10 hours ago
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Quantum Physics Just Got Less Complicated

barlevg Re:more simplifications and fewer cats, please (170 comments)

So I haven't read too much into pilot wave theory, but it's a hidden variable theory, and according to Bell's Theorem, you can have hidden variables, you can have "locality" (meaning no action at a distance), but you can't have both. And most physicists would MUCH RATHER have locality than hidden variables.

10 hours ago
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Quantum Physics Just Got Less Complicated

barlevg Re:Thanks, next stop - single particles don't inte (170 comments)

One particle doesn't interfere with itself, and can't because the interference pattern is seen in the density of collisions over an area.

As many of these single dots build up, they tend to cluster around an interference pattern - as if some particles went through one slit, and some particles went through the other slit.

Not quite--and that's really the key element of this whole thing: the particle somehow DOES interfere with itself, because the interference pattern that builds up, just one particle / one dot at a time is DIFFERENT than what you'd get if each particle only went through one hole. Imagine you're up on a ladder, dropping beanbags through a plank with two slits in it (you can cover those slits if you want), and they form a pile on the ground below. If the beanbags can only go through one slit, the pile you get on the ground is a nice mound. If you open up BOTH slits, then what you expect is TWO mounds. If the slits are close enough together, you expect those mounds to overlap, with the height at each spot being AT LEAST AS HIGH as the height you'd see dropping the beanbags through just one hole.

But instead, what you see in the double-slit experiment is that, in between the two mounts, you get spots where there are FEWER beanbags than you'd get dropping them through just one hole. Somehow, instead of getting that 1+1=2, you're finding that 1+1=0. The beanbags are all still there--it's not like they're cancelling each other out.. they're just not all where you'd expect them.

The ONLY WAY to explain this (that we've found so far) is if each beanbag, which, again, you're dropping one at a time, somehow goes through BOTH slits and INTERFERES WITH ITSELF. This is where the idea of wave-particle duality comes in, because the patterns that you see (with valleys where there should be ridges) are similar to what you'd see with water waves or sound waves (sound waves can cancel each other out--that's the whole premise behind noise-cancelling headphones).

So then why don't we just say that photons (and beanbags) are waves and not particles at all? Well, because classical waves aren't "quantal," meaning you can't divide sound waves into discrete, indivisible components. You can have one "particle" of light (a photon). There's no corresponding discrete element of sound. So we say that they're particles after all, and simply adjust our thinking regarding just what a particle is and how one behaves.

11 hours ago
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Quantum Physics Just Got Less Complicated

barlevg Re:more simplifications and fewer cats, please (170 comments)

Ok, let me give this a crack.

You build a box. That box contains a Geiger counter, which clicks if it detects the decay of a particle. Because you're a sick, sadistic fuck, you hook up that Geiger counter to a hammer such that if the Geiger counter detects the decay, it engages the hammer to smash a vial of poison, thus releasing it into the box. You then--because, as I said, have issues with sociopathy--put a cat in the box and close the lid. The box is very thick, completely opaque and completely soundproof. You have no way of knowing what's going on inside the box.

You wait an hour. In that hour, you do some maths that shows that there was a 50% chance that the particle decayed, triggering the Geiger counter, which triggered the hammer to break the vial of poison, releasing the gas and killing the cat.

The question becomes: before you open the box, is the cat alive or dead? Or is it somehow...both?

Your gut instinct is to say, "That's stupid. Of course it's either alive or dead. How the fuck could it be both?"

But the thing is, there are certain, non-cat-related experiments that we've done that REQUIRE the answer to be BOTH. Perhaps the simplest (and certainly the one we physicists learn about first) is the double-slit experiment. The basic idea is, you shoot a beam of something (light, gold atoms, DNA, doesn't really matter) at a slit, and it forms a pattern on a wall. It'll form this pattern even if you shoot your particles one at a time. Then, you close that slit and open another one, and fire your beam again. It forms a different pattern.

Now you open BOTH slits and fire your beam. What happens? Well, what you'd expect is to get a pattern that's the SUM of the pattern you get through each slit. That corresponds to the idea that the particles each go through either Slit 1 or Slit 2. But instead what you get is an INTERFERENCE pattern, which can ONLY happen if the particles are going through BOTH HOLES. And recall I said earlier--you get the same pattern even if you shoot your particles one at a time, which means THE PARTICLE MUST BE INTERFERING WITH ITSELF.

So back to the cat: is it alive or dead, or is it alive AND dead? According to the Copenhagen Interpretation, it's both. But that's why the cat thought experiment was devised in the first place: to highlight how RIDICULOUS that was. The crazy thing is that, seventy years later, we don't really have a better interpretation (at least not one that's widely accepted). So until someone builds this possibly-cat-killing box, we won't really know if the Copenhagen Interpretation is right, or whether something even stranger goes on when quantum events get amplified to the macro level.

One final note: practically speaking, there's no way to build this experiment, because of the whole "you have no way of knowing if the cat is alive or dead without opening the box" part. Isolating a system as big as a cat-box from the rest of the universe is not really feasible. You would also have to construct a particle decay detector that did not, itself, "collapse" the waveform of the decaying particle (otherwise the paradox is resolved before you ever make it to the cat).

Hope that was helpful!

11 hours ago
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Quantum Physics Just Got Less Complicated

barlevg Interesting paper, stupid summary (170 comments)

Here we show that [wave-particle duality relations] correspond precisely to a modern formulation of the uncertainty principle in terms of entropies, namely the min- and max-entropies. This observation unifies two fundamental concepts in quantum mechanics. Furthermore, it leads to a robust framework for deriving novel WPDRs by applying entropic uncertainty relations to interferometric models.

So they're looking at it in terms of entropies, and when they do, it resolves a debate about whether WPDRs are equivalent to the Uncertainty Principle AND generates new WPDRs.

12 hours ago
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Army To Launch Spy Blimp Over Maryland

barlevg Balls (175 comments)

You can't tell me that thing doesn't look like it has a scrotum.

2 days ago
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The Case For Flipping Your Monitor From Landscape to Portrait

barlevg Would love to do this (566 comments)

But both of my desktop monitors are locked into landscape. Now what I'd *really* like to see is a portrait (or a flippable) LAPTOP monitor...

about a week ago
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Complain About Comcast, Get Fired From Your Job

barlevg Re:Comcast needs to go the route of AT&T (742 comments)

Unless they're allowed to compete in the same markets, I'm really not sure how that would help.

about 2 months ago
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Living On a Carbon Budget: The End of Recreation As We Know It?

barlevg Dimensional analysis (652 comments)

is about 1700kW/h electric.

Not impressed? Was not meant to impress you. That is per year not per month.

Quick pedantic note: the unit is kWh, not kW/h. Watt is energy over time. So Watt / hour would be energy over time squared. Your energy consumption per year is 1700 kWh or 6120 Megajoules.

about 2 months ago
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On Independence for Scotland:

barlevg Re:Shetland and Orkney (192 comments)

Yes, this is correct, and my bad for perpetuating the myth. I read once that Shetland was closer to Oslo than Edinburgh, but that's also blatantly false. The more relevant Norway/Scotland fact is simply that Shetland used to belong to Norway, so their historical ties to Scotland are weaker.

about 3 months ago
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On Independence for Scotland:

barlevg Shetland and Orkney (192 comments)

The interesting question to me regarding Scottish independence is what will happen to Orkney and Shetland (the latter of which is closer to Norway than Scotland). Shetlanders often don't consider themselves Scots, and so the thinking is that they might seek their own independence if Scotland breaks away from the UK. And that would likely have huge ramifications for Scotland's oil trade, since a lot of the resources, as I understand it, are in the North Sea.

about 3 months ago
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Power Grids: The Huge Battery Market You Never Knew Existed

barlevg Never knew existed? (245 comments)

I've been hearing about batteries being needed for sun and wind is as long as I've been hearing about sun and wind...

about 4 months ago
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Old Doesn't Have To Mean Ugly: Squeezing Better Graphics From Classic Consoles

barlevg Was expecting an article on upscaling filters (167 comments)

I was really excited to see that new builds of ffmpeg (which is FOSS) implement the hqx family of filters, but I've also read that these filters are pretty outdated at this point. So I was hoping that this article would be a comparison of upscaling algorithms, both free and proprietary. But alas...

about 4 months ago
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The Flight of Gifted Engineers From NASA

barlevg Re:Another sign NASA is circling the drain ... (160 comments)

Wow is this uneducated. I can't speak to the federal workforce as a whole, but for a variety of technical fields, like the one described in this article, as well as my own (data science), the federal government pays "competitively" but salaries in the private sector tend to be quite a bit higher. As for the hours and the benefits, that's largely a function of where you work, but I will point out that federal pensions for new hires got slashed as part of a recent round of budget negotiations.

about 4 months ago
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Ancient Worms May Have Saved Life On Earth

barlevg Re:Tiny? (54 comments)

Sandtrout were pretty tiny and just as integral to the Dune ecosystem (IIRC, melange was their excretion).

about 4 months ago
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How long ago did you last assemble a computer?

barlevg Re:"assemble" or "reassmeble" (391 comments)

What if your mobo shorts out and that's all you need replaced? That, to me, is a lot less of a change in computer than a CPU upgrade or a new hard drive: replace one of those, and your computer will run noticeably differently, but if someone were to come into your house and swap out the motherboard of your computer in the middle of the night, you might not even notice a difference assuming the BIOS was the same.

about 5 months ago
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How long ago did you last assemble a computer?

barlevg Re:so, I'm in the more than 8 yrs ago camp (391 comments)

The manufacturer clearly fucked something up with that Windows machine, since, as I said, its twin (purchased at the same time with identical hardware) worked out of the box. As for my xorg issues with my Linux tower, I'm not actually sure that it *wouldn't* work out-of-the-box, if I had installed from the LiveCD with the monitors plugged into the graphics card instead of the IGFX. But trying to switch to using the card now, post-install, would be an unnecessary pain. And trying to run one display off the IGFX and the other off the video card would be a nightmare. Shameful in a modern OS? Sure. But we've known that X11 needed to be replaced for a while.

about 5 months ago

Submissions

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Mr. Schmidt Goes to Washington: a Look Inside Google's Lobbying Behemoth

barlevg barlevg writes  |  about 8 months ago

barlevg (2111272) writes "In May 2012, in the midst of an FTC investigation into Google's search practices, the law school at George Mason University in Northern Virginia hosted a conference attended by congressmen, regulators and staffers. The topic: competition, search and social media. What none of the attendees of the conference knew was that Google was pulling many of the strings behind the event, even going so far as to suggest invited speakers.

This event, as documented in The Washington Post is just a snapshot of the operations of one of the largest and highest spending lobbying entities in DC, a far cry from the one-man shop it started out as nine years ago, from a company "disdainful" of Washington's "pay-to-play" culture."

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ZunZuneo: USAID funded "Cuban Twitter" to undermine Communist regime

barlevg barlevg writes  |  about 9 months ago

barlevg (2111272) writes "In a country where the government severely limits access to the world wide web, ZunZeneo, an anonymous SMS-based social network, drew more than 40,000 Cuban users at its peak, the Associated Press reports. On it, people shared news and opinions about music and culture. But what none of its subscribers knew was that the project was secretly funded by the United States Agency for International Development (USAID), though a series of shell corporations and foreign bank accounts, and that its stated goal was “renegotiate the balance of power between the state and society” in the Communist stronghold, hopefully leading to a "Cuban Spring.""
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Polar Vortex Likely Decimated Stink Bug Population, Experiment Suggests

barlevg barlevg writes  |  about 10 months ago

barlevg (2111272) writes "Each fall, a team led by Virginia Tech Professor of Entomology Thomas Kuhar gathers brown marmorated stink bugs from around campus and plops them into ventilated and insulated five-gallon buckets designed to simulate the habitats in which the bugs naturally wait out the winter. While previous lab tests have shown the insects capable of surviving chills of -20 C, last month's polar vortex proved too much for the little guys, with only 5% surviving the sustained cold conditions. This suggests that the DC area's population of stink bugs and other overwintering insects should be much lower come spring than in previous years."
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Irony is Dead: Tea Party Posts Material from Bioshock Infinite to Facebook Page

barlevg barlevg writes  |  1 year,2 days

barlevg (2111272) writes "The National Liberty Foundation, a Tea Party group, posted to their Facebook page an image featuring George Washington keeping at bay a crowd containing a wide assortment of ethnic groups above a banner reading "It is our holy duty to guard against the foreign hordes." While such images are hardly uncharacteristic of the group's photo stream, this particular image was in fact promotional material from from Irrational Games' BioShock Infinite, set in a dystopian city controlled by warring factions that "strive to keep the city for pure Americans" and worship the founding fathers as deities."
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FDA Not Convinced Antibacterial Soaps Stop the Spread of Germs

barlevg barlevg writes  |  1 year,3 days

barlevg (2111272) writes "It's long been a concern that the widespread use of antibacterials soaps is contributing towards the evolution of drug-resistant "superbugs," but as the Washington Post reports, the Food and Drug Administration also does not believe that there is any evidence to support that the antibacterial agents in soaps are any more effective at killing germs than simply washing with soap and water. Under the terms of a proposal under consideration, the FDA will require that manufacturers making such claims will have to show proof. If they fail to do so, they will be required to change their marketing or even stop selling the products altogether.

The Washington Post cites concerns that triclosan interferes with hormone production, but it should be noted that is is based on animal studies, and that at least one human study has shown no effect on hormone levels in adults using toothpaste containing triclosan."

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NSA Broke Into Links Between Google, Yahoo Datacenters

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "The Washington Post reports that, according to documents obtained from Edward Snowden, through their so-called "MUSCULAR" initiative, the National Security Agency has exploited a weakness in the transfers between data centers, which Google and others pay a premium to send over secure fiber optic cables. The leaked documents include a post-it note as part of an internal NSA Powerpoint presentation showing a diagram of Google network traffic, an arrow pointing to the Google front-end server with text reading, "SSL Added and Removed Here" with a smiley face. When shown the sketch by The Post and asked for comment, two engineers with close ties to Google responded with strings of profanity."
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White House Fires Employee Over Anonymous Twitter Feed

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "@NatSecWonk, a Twitter feed posting (often scathing) commentary on the administration's foreign policy and on reporting of national security issues, went dark last week, and its owner, unmasked as Jofi Joseph, a member of the National Security Council and an expert in nonproliferation, was reportedly fired. None of the tweets contained any information of a classified or sensitive nature, so any further action against Joseph seems unlikely."
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Overcoming Racism in Cinema... From the Technical Side

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "Since the birth of film, shooting subjects of darker complexion has been a technical challenge: light meters, film emulsions, tone and color models, and the dynamic range of the film itself were all calibrated for light skin, resulting in dark skin appearing ashy and washed-out. Historically, filmmakers have used workarounds involving "a variety of gels, scrims and filters." But now we live in the age of digital filmmaking, and as film critic Ann Hornaday describes in the Washington Post, and as is showcased in recent films such as "12 Years a Slave," "Mother of George" and "Black Nativity," a collection of innovators have set to work developing techniques in lighting, shooting and post-processing designed to counteract century-old technological biases as old as the medium itself."
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Full Screen Mario: Making the Case for Shorter Copyrights

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "A college student at Rensselaer Polytechnic Institute spent nine months meticulously remaking Super Mario Bros. based on the latest web standards. His project is open source and the code freely available through Github. The site recently gained widespread media attention, which unfortunately brought it to the attention of Nintendo, which has requested that the site be taken down.

In a column on the Washington Post website, tech blogger Timothy Lee makes the case for how this is a prime example of copyrights hindering innovation and why copyright lengths should be shortened. Among his arguments: copyrights hinder innovation by game designers seeking to build upon such games, and shortening copyright would breathe new life into games who have long since passed into obsolescence."
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Nobel Winners Exemplify Israel's "Brain Drain" Problem

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "Two of the three scientists sharing this year's Nobel Prize in Chemistry have Israeli citizenship, with Dr. Arieh Warshel having been born and educated in Israel, yet both are based at universities in the United States. These two scientists are perhaps the highest profile examples of a growing problem in the so-called "start-up nation," which is known for its high-tech tech companies and scientific innovation, and yet which loses more researchers to emigration than any other western nation. The problem? Large salary gaps between US and Israeli institutions. As Daniel Hershkowitz, president of Bar-Ilan University put it, "I don't see Israel being able to compete with what they offer in the United States.""
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Most Cave Paintings Were Painted By Women

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "Analyzing hand-prints found in cave sites, an archaeologist from Penn State University has concluded that roughly 75% of all ancient cave art was painted by women. Previously it was thought that neolithic cave paintings were made mostly by men, perhaps to chronicle their kills. But an analysis of the relative lengths of fingers in hand stencils found on cave walls suggests that it was mostly prehistoric women--not men--who created these works."
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Chemical Analysis Separates Cat Poop Coffee from Fakes

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "Kopi Luwak, or civet coffee, consists of coffee berries that have been partially digested by an Indonesian tree-dwelling cat called the palm civet. The digestive process, coupled with the wild civet's selectivity in eating from the choicest plants, is said to impart an exquisite, exotic flavor. However, its high price (the coffee can retail for as much as $600 per pound) has led to the market being flooded with fake and low-grade products, which may contribute to negative Western impressions of the brew. Now, a team of Japanese scientists have developed a test for separating the real beans from knock-offs by looking at tell-tale signs of the civet's predigestive process in the finished product (abstract here). Says researcher Sastia Prama Putri, "We want to be sure people around the world can try the real Kopi Luwak."

As an aside, animal cruelty is also a concern, as the high demand for Kopi Luwak has led to civets being captured and caged. As civets in captivity have no choice about what they eat, it is likely these caged animals produce an inferior product to their wild counterparts."
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New Brain-to-Brain Interface Allows Human to Control Another's Movements

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "Earlier this year, researchers at Harvard devised a system by which a human could control a rat's tail using only the person's thoughts. Now a team at the University of Washington have demonstrated that the same principle can be applied to human-to-human control. The Washington Post reports: "First, they placed electronic probes against their heads. Then one man looked at a computer game on a screen and thought about what move he wanted to make. Sure enough, the other man, who was across campus with no view of the screen, almost instantaneously moved his right index finger to make that move. He said it had the sensation of a nervous tic.""
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Study Suggest Violent Video Games May Make Teens Less Violent

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "A new paper is out in the Journal of Youth and Adolescence which shows no positive correlation between playing violent video games and acts of aggression. The study of 377 children with attention deficit and depressive symptoms in fact showed a slight negative correlation between video game-playing and aggressive behavior such as bullying, which the researchers posit is due to the games awarding some measure of catharsis. The full paper is available online (PDF)."
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NWS to Al Gore: There Is No "Category Six" Hurricane

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "In a recent interview, former Vice President and environmental activist Al Gore made a bold claim, that man-made global warming was causing hurricanes to be formed of such severity that "they’re adding a 6" to the hurricane scale, going on to say that "The fingerprint of man-made global warming is all over these storms and extreme weather events." In response, the National Weather Service has responded that they have no plans to add a "doomsday Category 6" to their rating scale: "No, we’re not pursuing any such change. I’m also not sure who VP Gore means by 'they,'" also noting that "Category 5 has no ceiling: it includes hurricanes with top sustained winds of 157 mph and higher." Furthermore, a recently leaked United Nations climate assessment claims only “low confidence” of a link between human activity and increased hurricane severity and that this is likely due to increased human settlement in coastal areas and other regions vulnerable to natural disasters."
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Weather Control Conspiracy Theories are Scientifically Lucicrous

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "The Washington Post's Capital Weather Gang breaks down two popular conspiracy theories: that HAARP is responsible for severe weather and that contrails from commercial airliners are actually "chemtrails" sprayed for nefarious purposes, and explains why each is preposterous to anyone with even an elementary knowledge of meteorology or an iota common sense. The author readily acknowledges that his analysis will do nothing to convince the tinfoil-hat-wearing, vinegar-spraying members of the populace."
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Google continues to translate "undocumented" as "illegal immigrant"

barlevg barlevg writes  |  about a year ago

barlevg (2111272) writes "While the New York Times, the Associated Press and others have chosen to discontinue the use of the term "illegal immigrant" in favor of "undocumented" Google Translate continues to translate the Spanish word "indocumentado" as "illegal immigrant." Google's response: "Since the translations are generated by machine, they’re not always perfect, but we're constantly working to improve the quality of our algorithms, and we appreciate this feedback.""
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