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### 2 Futures Can Explain Time's Mysterious Past

Re:The thermodynamics explanation is circular (107 comments)

Entropy requires time in which to move to a more disordered state.

Time exists because entropy becomes more disordered.

Hmm. Spot the logical flaw there.

Ok. Your logical flaw is a strawman argument. While the article claims entropy is responsible for the arrow of time, i.e., the directionality of it, you pretended it said it's responsible of the existence of time at all. Then you argued against your own statement and pretended that was a valid argument against theirs.

Here's what they're actually saying. Assume time exists. So entropy can either increase or decrease with the passage of time. However, there are many more configurations with increased entropy than decreased entropy, which means a statistically implied direction towards increased entropy.

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### Mathematical Proof That the Universe Could Come From Nothing

Again no. A running coming from the other direction would see the doors close in the other order. I think the AC parallel to this post explains it pretty well.

This is a highly misunderstood topic, I'm going to try to clarify it.

You're correct about the concept of simultaneity in relativity. In the barn door example, depending on your frame of reference, the bars could open simultaneously or one after the other.

He's correct about causality in relativity. Causal events are invariant. There is no frame of reference in existence, regardless of your velocity or distance, in which an object shot by a bullet fired from a gun gets hit before the gun is fired. It can't happen. It doesn't happen because with such a causal event, at some point the bullet and the gun were at the same location and the distance between them was 0. Time dilation depends on speed and distance, because time dilation requires an accompanying lorentz contraction. After the bullet is fired, depending on your frame of reference, people can disagree how far the bullet is from the gun, how far the target is from the gun, and therefore how long it took the bullet to travel from the gun to the target. But no frame of reference exists in which people observe the target being hit and then the gun firing the bullet.

about a month and a half ago
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### Journal Published Flawed Stem Cell Papers Despite Serious Misgivings About Work

Re:peer review is a low bar (35 comments)

Peer review filters out the stuff that is obvious crap, stuff that doesn't even fit the form of a proper scientific article. The purpose is not to say that articles are true, but rather to get rid of articles that are obviously wrong.

If the scientists are lying about their data, it's hard for peer review to catch that. That's why reproducibility is important. If it's a result you care about, you can reproduce it.

Well, reproducibility is part of peer review. If anyone is making decisions based on the results of one paper, they're idiots. Even if the research methodology was flawless, and the researchers are brilliant and honest with all their data, certain results can still come about as a result of chance. Obligatory xkcd

I wish we'd put more emphasis on reproducing published results, though. I've mentioned this before, but I feel like this would be the ideal work for grad students during their first few years, before they're deep in their own research. They need to get papers published, there should be journals devoted to publishing data from reproducing results. Students get experience writing papers and conducting research and everyone gets stronger peer review in their fields.

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### Statistics Losing Ground To CS, Losing Image Among Students

The problem is that AP classes are, pretty uniformly, badly constructed. Half of the education in AP math and science courses is How to Use the TI-83 Calculator. Half of AP Computer Science is How to Program in Java. The College Board is single-handedly blocking progress in the education of technology in math and science.

Yeah, but they replace the low-level introduction courses in college, not the more advanced ones. 100-level computer science courses in college ARE, "how to program in Java." And, like I said, my Calculus course in High School seemed better than the equivalent in college from what I was seeing.

If anything, those high school courses mean you don't have to take the BS introductory courses in college, and you can go straight to the more interesting / demanding ones during your freshman year.

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### Statistics Losing Ground To CS, Losing Image Among Students

He may be right about AP Statistics though. Taking statistics in high school means that most people will have forgotten it by the time they get to advanced courses that use statistical methods.

Unless you're an actual statistics major (in which case you'll pick up whatever you missed in subsequent courses anyway), that's going to be true regardless of whether you take statistics in high school or college. I took AP statistics, but my university required me to take "Statistics for Engineers" as an EE major, and wouldn't allow the AP stat course to count towards that. Stats for Engineers was an absolute joke, and the high school class was for more rigorous.

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### Statistics Losing Ground To CS, Losing Image Among Students

It stands for "Advanced Placement." They're college-level high school courses. At the end of the year, you take the advanced placement exam, and depending on your scores and the college you attend, you can get college credits for them.

I think getting rid of an AP is a stupendously short-sighted idea. Having students take more advanced courses earlier is a great idea. If there's reason to believe the courses aren't actually as demanding as their college equivalent (and I don't think there is, based on my experience taking AP Calculus in high school and looking at what people taking Calculus in college were seeing. We covered the same material, and if anything my high school class covered more), then you can make an argument for the tests more challenging / add to the requirements of those courses. Getting rid of it is just an attempt to waste students' time and extract more money from them by forcing them to take more university courses.

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### Snowden: NSA Working On Autonomous Cyberwarfare Bot

You think its right and normal that the NSA can spy on 7 billion souls? You re ok with that? Disgusting, you really dont belong here.

To be fair, I also think it's right and normal for foreign intelligent agencies to try spying on Americans. It's our counter-intelligence job to prevent it.

The NSA should be sure as hell trying to spy on every single non-American out there. It's their counter-intelligence job to limit it.

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### Snowden: NSA Working On Autonomous Cyberwarfare Bot

That seems amazingly charitable, considering he should really get a presidential pardon and be welcomed back as the heroic guy who did the right thing to expose law breaking and billions of constitutional violations.

If the only thing he did was expose the illegal spying being done on Americans, I'd agree with that. But he indiscriminately takes everything he can get his hands on and reveals perfectly legal programs, like this one. "Identifying and blocking foreign threats" is the NSA's job, and why wouldn't that include cyber attacks? What justification does he have for revealing this?

I think we should specifically pardon him for for the relevant whistleblowing, to encourage other people in those positions to do the right thing. But we should sure as hell prosecute him for everything else he's leaked.

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### Why the "NASA Tested Space Drive" Is Bad Science

Re:BLINDED BY SCIENCE !! (315 comments)

Any 2nd year physics student should be able to laugh this garbage right off a lab bench without even running an experiment.

Any good science student should be aware that our understanding of physics changes over time. Clearly this device is unlikely because it requires a change to the "laws" of physics.

The article explains why any good scientist should be able to laugh this off based on the reported experimental results.

The problem is that the article is saying this is bad science, when it's really bad science reporting

NASA did the right thing. They tested something, they got weird results, they published it. The article points out the results were no different than the null control, and that's true, so clearly the supposed design of the drive is bullshit. What the article doesn't point out is that the interesting part is that neither of them should have shown any thrust. So something is going on that the experimenters don't understand, and they've published the results to find out why. Is it a measurement / equipment / methodology error? Probably, actually. But if you can't find the error yourself, you publish the results you get, and let your peers help you. Papers will be published criticizing their methodology if there are problems with it, or proposing reasons for why the measurements look like they do. It's a long shot, but maybe there is some effect actually happening which we don't understand, and papers will be published with possible theories.

That's not bad science. It's the definition of good science. It's bad science to imply that you should ever not publish the results you get. And it's bad science reporting to look at what NASA published and incorrectly translate it to the public as, "NASA proves impossible drive"

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### Expensive Hotels Really Do Have Faster Wi-Fi

Re:How much is due to Congestion (72 comments)

If WIFI is free, everyone will use it, clogging up the pipes. If there's a charge, less people will be on, making more BW available for those who shell out the cash. I also hope that the hotels that charge use the money to miantain the infrastructure, but that's wishful thinking on my part.

On the other hand, I used to pick hotels based on my free WiFi experience. So if you charged for WiFi, I'm not paying for a room at your place. If two different places have free WiFi, but I had a flaky connection in one hotel,and an ok connection in another, that's the deciding factor. All other concerns were secondary.

Of course, I would also have considered the case where the \$10 a day a hotel would charge for WiFi would make up the difference in room cost, but it always turns out that expensive hotels charge for WiFi and cheap hotels don't, so that never came up.

These days I don't care, because 4G.

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### Apple Says Many Users 'Bought an Android Phone By Mistake'

alternate browser: chrome and opera are available for iPhone, and probably ffx too ( i never checked). you can put the browser on your dock and take the safari browser off your dock. the only limitation is you can't change the default browser for which program is used when opening links in an email, etc. but otherwise do what you want.

Nope. All third-party browsers in iOS must use the iOS webkit framework. So yes, you can get "chrome" for iOS, but really it's just a Safari skin. Case in point, you can't use chrome extensions on it.

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### The Energy Saved By Ditching DVDs Could Power 200,000 Homes

Re:It's the energy cost of the drive (339 comments)

That 50% assumption is stupid. You can't stream the food items or other things you buy while you're at that store. So you need to go to the store anyway, DVD or not.

I agree completely. If you're going to make the trip for any item, plus dvd, the only fair comparison is the extra energy used to carry the weight of the dvd around as a percentage of the other items you bought. Which would, of course, be negligible.

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### SEC Chair On HFT: 'The Markets Are Not Rigged'

Re:So how fast does real world value change? (303 comments)

If you accept that the market system is a way of determining the value of securities, then what does HFT mean? How is it possible for real world value to change over the course of milliseconds?

Conversely, if I offer to sell you 5 oranges at \$1.00 and they immediately sell at that price, I'm going to offer my next 5 oranges at \$1.20. How fast did the price rise \$1.20? How fast did I make my next offer? I could continue selling oranges at \$1.00 for a month, but if people are buying a ton of them, and I think I can sell all my oranges for more money, it's in my advantage to up the price as quickly as possible. So, milliseconds after your order went through, I could decide to sell the next batch at \$1.20.

There's absolutely nothing nefarious about millisecond trades and price changes, if that's all that's going on. The only difference from "real world phenomena" is that the brokers have algorithms to increase or decrease the share price automatically based on the supply and demand it sees. In a very high trade volume situation, that time matters. If you're faster than your competitor, people are buying and selling *from you* because your prices are always better, closer to the optimal given the supply and demand for the stocks. That's how you make money being faster.

Second, HFT helps you get the "real world value" because the way you get a "real world value" is through iteration. When I decide to sell you oranges at \$1.00, that's not the real-world value of oranges. That's a guess I made at the price, assuming there would be exactly enough demand for oranges at \$1.00 as I have the ability to supply it. If people are willing to buy it at a higher price, I'll find that higher price faster the quicker I can perform trades and vary my price, and the more trades that I can make. Same if people are only willing to buy it at a lower price. It's no different than, say, if I want to find the square root of a number via the Babylonian Method. If I have a computer running at a low clock frequency, each iteration might take a second. If I have a computer running at a high clock frequency, each iteration might take a microsecond. They both get to the same answer, but a higher clock frequency gets you that answer faster. Again, nothing nefarious about that, and it means that at any one point a human looks at the price of stocks, it's a value that most accurately reflects that equilibrium price between buyers and sellers, because all the iterations are happening very fast.

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### Scientists/Actress Say They Were 'Tricked' Into Geocentric Universe Movie

Re:Something which I do not understand (642 comments)

Cosmologists say that when we look in the sky and all the stars and planets, we can see them escaping us. This explains that the universe is expanding. But if we can observe the same thing from every side of Earth, wouldn't it mean that we are in the center?

It's a good question. Try this video

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### Woman Attacked In San Francisco Bar For Wearing Google Glass

just stop pointing your camera at me. I don't care if it's showing a red light or not. She was being obnoxious, and wouldn't stop when asked.

You don't have the right to have someone not point a camera at you. You can leave, and cover your face, but you can't really force them to stop. You can politely tell them that it makes you uncomfortable, but if they want to be assholes about it, there's no law against being an asshole. There's definitely a law against you assaulting said asshole and/or stealing their property.

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### Woman Attacked In San Francisco Bar For Wearing Google Glass

Re:what will it take for general acceptance (921 comments)

Filming is what you do to other people

Oh? What exactly are you doing to other people when you film them? Stealing their soul?

If you're not touching somebody, you're not assaulting them. If you're not following them as they try to leave you, you're not harassing them. Filming somebody is not doing anything to them anymore than loudly talking about them to somebody else, so that they can hear. They're peripherally involved, they might be annoyed by it, but they don't have any right to stop you.

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### Woman Attacked In San Francisco Bar For Wearing Google Glass

Re:what will it take for general acceptance (921 comments)

Sure they have. And sometimes they get attacked. Happens all the time. But since it is not google glass, it doesn't make it to slashdot. People don't like to be recorded without their permission. It doesn't matter if it is google glass. This article attempts to make it sound like google glass users are a group that is discriminated against. That is not the case.

I don't know what bar you go to, but I've never seen that, ever. In fact, if the bar has live music, I've never been to one without at least 20% of people recording.

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### Woman Attacked In San Francisco Bar For Wearing Google Glass

Re:Take pictures, press charges. (921 comments)

Apparently there is, even if the law doesn't currently recognise it. Maybe that law is out of date and should be changed.

I don't think so, but let's say you're right. The trick is that recognizing such an expectation of privacy cannot mean that you just ban cameras you're uncomfortable with. You have to ban security cameras. You have to ban reporters who are covering a story. You have to ban people taking selfies at bars and other locations where it's not possible to ensure someone who didn't consent will show up in the background.

If the majority of people in a jurisdiction are willing to go with that, then yeah, the law should be changed. I think they're not. I think the first time you take your phone out to take a picture of something cool you've seen and other people tell you that you can't do that, you're going to throw a fit. People don't really think they have an expectation of privacy at those locations, they just feel uncomfortable when they see a camera next to them because it makes it obvious that they have no expectation of privacy, and they don't like to be reminded of that. They like to pretend they're not ending up on the background of tons of pictures, or being laughed at by the police who is reviewing security tapes because someone's wallet was stolen at the same time you were at the bar getting slapped for the stupid line you tried to use.

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### Woman Attacked In San Francisco Bar For Wearing Google Glass

Re:No, not those who don't understand... (921 comments)

Holding the camera up pointing at the room with the screen towards you would be offensive whether or not you were filming.

No. In a public location, bringing a high quality video camera out, setting up on a tripod, and pointing it at straight at you is perfectly acceptable. It's a public location, you have no privacy. You are within your rights to leave, to cover your face, to turn your back to the camera. You can't attack the owner of said camera, or take the camera away.

At the bar you own, or at your house, or at any private property in which the owner doesn't want the device on, you absolutely have the right to kick anybody out who doesn't follow the rules. But somebody is perfectly within their rights to stand in the public street and point a camera at your house window. The only legal recourse you have is to close the blinds.

This obviously depends on the jurisdiction in your area, and whatnot. However, for a lot of the US, that happens to be true. And it's the way it should be.

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I have hardly ever known a mathematician who was capable of reasoning. -- Plato