Researchers Develop Purely Optical Cloaking
but it only really works if the object has to stay within a certain limited area
Actually, it's even more trivial than that. As they explicitly say in the video, the object has to stay out of the central area. Why? because the central area is where you're focusing the light. Now if they would only take those four lenses, put them in a tube and 'cloak' an absorber around the focal point to remove stray light, they would have a marvelous invention. I suggest calling it a telescope.
Welcome to elementary optics class, now with Harry Potter themed experiments.
OKCupid Experiments on Users Too
It's called the "tyrrany of dimensions". The more variables you have, the more data points you need exponentially to derive meaningful partitioning analysis from it, regardless of how clever your distance algorithms are.
Indeed, but only if you insist on carrying along in your analysis all the irrelevant and correlated dimensions.
And they have hundreds of questions when a dozen would be about all the entire population of Earth could support.
So do surveys, for significantly smaller sample sizes. I wouldn't be surprised if a non-trivial percentage of those questions are intentionally redundant - you know, to check *ahem* consistency, improve accuracy, etc. If, say, you have 100 questions grouped into 10 categories with 10q/cat, you have just dropped the dimensionality significantly while at the same time having more confidence in your data. A rule of thumb in surveys is don't trust the user^W^W^W^W *ahem* trust, but verify.
Scientists Measure Magnetic Interaction Between Two Bound Electrons
It is the strength of the interaction that is found to be inverse cubic. The strength of magnetic force is inverse quadratic. If somebody found evidence of an inverse cubic force then this would be evidence of higher-spatial dimensions and very unexpected indeed.
How did you get modded informative? The magnetic component of the force between electrons in this case is indeed proportional to the inverse cube of the distance. Elementary magnetostatics, since it's the interaction force between two magnetic dipoles (look up dipole-dipole interaction if you want to see the formula). No higher dimensions or other mumbo jumbo required.
High Frequency Trading and Finance's Race To Irrelevance
Until people can recognize the difference between front running (a biased ordering of particular market events) and high frequency trading (low latency response to available market data) then there really is no point in responding to this nonsense.
You seem confused about what frequency means - hint, it's not the inverse of latency. HFT is about (very) low asset holding times, not low latency of the response (although the latter is a necessary means). Case in point, the low latency part, when uses to provide liquidity (as the standard argument goes) would be indifferent to trading patterns - much like a market maker in a stock doesn't pick and choose trades and usually has a requirement to, you know, be there to make the market if needed. HFT, in the fast flipping sense that gave the name, has no such compulsions and very much cares about trading patterns, which together with trend hunting algos has a negative effect on price stability (statistically prone to abrupt swings in both directions).
So do try to understand that high frequency and low latency do not describe the same thing. Otherwise people might start to think that there really is no point in responding to your posts.
30-Day Status Update On LibreSSL
... and not really that multiplatform for future development, either, since it requires (as per the linked slide)
Modern C string capabilities (strl[cat,cpy]) asprintf etc.
None of the quoted functions are standard C and strl* are BSD-only - yay for GNU-BSD strn*/strl* string function wars :(
It's all nice and good practice that they want to use the best tools available to them on OpenBSD, but not caring for what's available on other platforms is not really how one does portability and *will* produce forks, regardless how much the LibreSSL authors want to 'discourage' it.
Is There a Limit To a Laser's Energy?
He is indeed talking about 1 MeV per photon.
he is jumbling together a lot of nonsense, imnsho.
He starts with the idea of an ordinary laser. Those are not even in the X-ray range, nevermind the MeV gamma-ray range. Then he wants to 'compress' the lasing cavity to *ahem* reach black-hole level of energy densities. While you can transfer energy to the radiation field (thus shifting up photon energies from the visible/UV range) you'll need a HECK of a fast compression to reach the electron-positron generation threshold. So that's nonsense.
Second, lasing does not happen in effing vacuum. Your first problem if you increase photon density, assuming your mirrors do not start to degrade before that, is nonlinear effects. Both in the lasing medium and in the mirrors. You start losing photons via multiple photon absorption that will give you back a higher energy photon that most likely escapes your cavity (goes in the wrong direction most of the time, and when it goes in the right direction the decreased mirror reflectivity and absorption/reemission x-section will not keep that energy contained for long). He never even sees that one coming.
Third, his armchair laser building scenario conveniently ignores all the losses that a real laser system has to contend with. The most obvious part being heat dissipation. Your pretty 99.999% reflective mirror will start to degrade rather quickly if you increase too much the incident radiation density without keeping it adequately cooled (this goes back to several things - normal absorption coefficient in that 0.001% that does not get reflected, having a lasing medium inside the cavity that loses energy to walls, nonlinear absorption effects in the mirror, etc.). Once that happens, you start to say goodbye to the containment properties of your lasing cavity, and thus to your 'bajillion increase in laser field energy density' plans for taking over the world. Try again tomorrow night, Brain.
Fourth ... bah, why bother. This is pretty much a jumbled collection of ideas that you'd expect from someone taking a first course in a given field and imagining things without an effective reality check. Perfect /. front page material.
European Parliament Votes For Net Neutrality, Forbids Mobile Roaming Costs
The most stable currency on the planet is the swiss franc
Shows what you know - the Swiss National Bank has maintained for the last few years an official 1.20 peg on EURCHF, by not letting the CHF appreciate more than that wrt EUR. Quite a remarkable thing, considering all the speculator howling at the time the peg was announced, basically everyone and their dog predicting a broken peg in a matter of months.
Regardless, that makes the CHF pretty much as stable as the EUR, so maybe you should reconsider looking down your nose on the economic knowledge of McD assistants. Vanity is such a funny thing, wouldn't you agree?
Nate Silver's New Site Stirs Climate Controversy
He also cited a U.N. climate report, along with his own research, to assert that extreme weather events have not been increasing in frequency or intensity.
Actually, no. I know, RTFA and all, but maybe you should work on it a bit?
He actually explicitly says that very costly extreme events did not increase in frequency and the ones that did increase, like heat waves and almost-but-not-quite-floods, do not make a major appearance on the cost maps. To wit:
In fact, today's climate models suggest that future changes in extremes that cause the most damage won't be detectable in the statistics of weather (or damage) for many decades.
Basically, that looking at absolute numbers of monetary damage is the wrong statistic for gauging overall extreme weather evolution. That's all there is to it.
Now, of course, his 'analysis' is quite flimsy, consisting in only normalzing overall disaster costs by GDP, with no crosstabbing for other factors. It has merits for pointing out the obvious pitfalls of lumping numbers together with little thought about what they mean. OTOH, if I had lost a wooden cabin to a tornado 20 years ago and last year the replacement concrete house also went the way of the dodo from a tornado, of course costs went up. But the sturdiness of the construction also went up, so it really does not rule out an increase in tornado intensity. And, contrary to some posts here, he did not take increased resiliency into account - no way he could, since he's using global statistics data that lumps together the SE Asia tsunami and US hurricanes.
OpenBSD Moving Towards Signed Packages — Based On D. J. Bernstein Crypto
So by your own admission it's now 'security that *ahem* silently Just Fails to Work on *all* installation media'? Awesome. Having it work on all - 1 (actually all - see below, but what's 1 between internet strangers) will definitely be a huge step back.
Besides, nobody said anything about 'silently failing' - you can put a big red warning sign about it on the download page. Also, you should still check the image signature for that itty bitty tiny floppy install to validate its integrity (as one would do with any install medium), and package sigs can be checked outside the installation procedure anyway. So I'm kind of mystified as to what point you were trying to make.
OpenBSD Moving Towards Signed Packages — Based On D. J. Bernstein Crypto
Even giving it the benefit of the doubt, what would break the process so horribly if a separately packed floppy disk installer does not check signatures (link gpgv to /bin/true for instance) while the other installers do? Floppy users don't lose or gain anything while the rest get the benefit of an untampered source assurance. Or are they also trying to argue that adding signatures won't let the regular installation packages fit on floppy disks?
US Executions Threaten Supply of Anaesthetic Used For Surgical Procedures
Apparently a combination of regulations and manufacturing problems. See here:
Now that is old news (2010) and apparently both Teva and Hospira are going to restart production ... slowly. However, unless and until they get a significant output going (not soon), Fresenius is the sole supplier, more or less. See here:
Collision Between Water and Energy Is Underway, and Worsening
So at 40% per year, in two and a half years there will be no water left in the bank. We are Doomed.
You my friend need to learn about exponential growth and, as in this case, decay. At 40% withdrawals each year there'll be water for ... somewhat more than a hundred years. By then we'll have the technology to give each citizen the correct number of water molecules they're allowed to withdraw from the bank.
Sadly, the H2O molecule is finite, however small - were water infinitely divisible we'd have had water forever AND test Planck scale effects in the not too distant future. Provided we also developed suitably small spoons, of course.
Orson Scott Card Pleads 'Tolerance' For Ender's Game Movie
if any sci-fi author will be regarded as one of the american greats, then it will be Frank Herbert for Dune.
Together with Roger Zelazny for This Immortal, obviously :-)
Digia Releases Qt 5.1 With Preliminary Support For Android and iOS
Nokia messed up by not staying the course. And now they announced they are happy being the challenger. Seriously?
It's understandable that one does not have time to keep up with the news, but at least RTF summary TITLE. Digia releases Qt 5.1. Nokia has had nothing to do with Qt for the last year or so, which is a Good Thing for the toolkit's evolution.
Have We Hit Peak HFT?
Since you want to touch on this ... heck, I have karma to burn, so why not?
Third, please find me a free market today that works the way the model predicts, and isn't literally destroying people in the process, merely to maximize profits.
As you well pointed out, this is not a realistic option. And the cause is simple, profit maximization misalignment with other motivations - in fact, it's inherent in free markets, where competing interests (for profit) motivate everything. Hence various side effects like negative externalities, worker exploitation, slavery, and so on.
My personal take on this is that while a real-world free market would be a system with too much complexity and chaotic behaviour to represent in a general model, simplified models with free-market rules can easily show ways in which the system reaches ... inefficient outcomes, like unfortunate equilibrium points (such as monopolies) or destructive oscillating behaviour (boom-bust cycles). It does not even require human flaws to get there, game theoretical models with rational agents will reach the same problem, due to inherent limitations such as imperfect information and unstable equilibria. Socialism in turn, besides not really being the alternative, has its own issues, some specific and some not so much (the unstable equilibrium of requiring every participant to have motivations aligned with a common good for one). The tricky part is, imho, the fact that legislating the market is not a true solution - introduce into the game the motivations of legislators and the issue of technical expertise required for tuning the system and you'll just run into a different 'who watches the watchers' class of problems.
To close this rant, IMHO markets need to be seen through dynamic models where there are often (if not always) segments to be watched for developments of bad outcomes - and I'm including regulators in the definition of 'markets'. Having a blind faith in either 'free' or 'regulated' is a lazy man's easy way out of an argument that is too complex to tackle, as market efficiency is something that requires vigilance from all participants, much like liberty.
HFT Nothing To Worry About (at Least In Australia)
The link you gave provided little insight into its cause. Do you have any more information about it?
The way I see it it's about the structure of the trades. From their text above the plots:
The price dropped from $796 to $775 in about 3/4 of a second, then rebounded to $793 a second later. The drop invovled 307 trades and 57,255 shares from 10 exchanges + dark pools. During the drop, there were 5 orders placed for every trade executed (meaning 4 orders placed/canceled for every trade).
Having about 1.5k quotes posted in 0.75s (with 80% being canceled) surely shows that HFT algos were active and yet did not absorb 57k shares of GOOG (that's about 2.5% of the daily volume at the time). Which is not a thinly traded stock by any measure. It's not a conclusive proof of HFT causing a drop of 2.5% in less than a second though, but I don't think you can easily get such a proof without knowing who traded what. There is only so much one can glean from trade data at this level after all.
Due to some time constraints I'll beg to be excused if, in lieu of the rest of the comment I was going to post, I'll give you this example (originally from here but the harvard link seems unavailable) of a HFT technique that, shall we say, 'plays' liquidity to increase volatility. The problem, as I see it, is how to discourage people who have the means to use them in such a fashion. Bear in mind that HFT requires quite an investment in infrastructure and software, so voluntarily refraining from taking advantage of that infrastructure in ways that exploit its advantage at the expense of slower traders is not a believable option. However, I'll also freely state that I have little faith in simple-sounding solutions to complex problems, which is what most pro- and anti-HFT rhetoric brings. Fortunately, it is not my job to find the proper solutions :-)
HFT Nothing To Worry About (at Least In Australia)
Some kinds of trading, including high-frequency trading, add liquidity; participants that do this are called market makers, and market makers reduce volatility by making it cost more to move the price.
Apologies, but you are mistaken. Market makers, in order to qualify as such (and receive the official designation from an exchange) have to satisfy certain condition that are not satisfied by HFT operations. The relevant ones for the 'provide liquidity' part are: to always maintain bid/ask quotes and stand by to execute trades at the quoted prices. There are rare exceptions when one can pull off, but that's the gist of it. Bit of a quaint notion nowadays, what with multiple connected electronic venues, but some exchanges still have it and it does use electronic quoting nowadays. However, this little detail does disqualify the majority if not all HFT shops from market making in the conventional sense.
Now, the good part that fast electronic trading does (which is not exactly the same as HFT) is pricing arbitrage between exchanges. Securities listed on multiple exchanges and/or in dark pools often enough get crossing prices, where one can arbitrate the difference and re-bring quotes in line. For example, when a price starts moving on one exchange (due to a block trade, let's say) price propagation is something that nowadays happens a lot faster. Similar things can be done with arbitrages between underlying instrument prices and derivative ones. If you choose to include this in HFT, then I'll grant you it's a good thing and it does improve liquidity[*]. It still does not make HFT players market makers, but arbitrageurs are good for price discovery[**]. However, you can't quite separate this part from the *ahem* 'evil' one, as you called it. It's simple market opportunity taking. Well, at least you cannot unless you start requiring a set of conditions that would make it unprofitable to engage in the behaviour you want to prevent.
Finally, going back to my original post, please do follow the link in there. It's not about 'the' flash crash, but one of the many single-stock flash crashes that happened since. This one was on GOOG, which is not an illiquid stock, and lasted less than 2 seconds. That's quite different from fat-finger crashes where extra-large orders are mistakenly placed and clear all the bids in the books on their way to the great below. (and btw, I do wish that my posts on this topic would stop getting irrelevant replies about the SPY flash crash when I'm not referring to that one and not even the same type of phenomenon)
[*] by decreasing quote spreads, which is the main proxy used for liquidity measuring. Still, I am yet to see convincing evidence for the part HFT played in this as opposed to the general improvement in connectivity between markets.
[**] However, having an option quote react faster to the price change of the underlying does not necessarily mean I'll get more liquidity for it. The liquidity question is thus tricker than it seems.
Have We Hit Peak HFT?
So, a thief who steals as much as an HFT corporation is also fine? Without the metric of social value, there is little or no point to many of the laws we have, especially the ones we think of as 'good'. I'd posit that if the social value of HFT is on par with grand theft, it should be outlawed, and for the same reason.
Well, my point is that markets (and in particular capital markets) are fundamentally about profit and nothing else. If you want to impose some additional system of values, be it social, ethical, religious (yes, there is such a thing in capital markets) ones, it has to be done from outside the 'free market' mentality. Because of that it amounts to extra regulation, so whether it is good or bad becomes a hot button issue in the US in general and on /. in particular and I chose to refrain from expressing a preference in a post that was more about facts.
HFT Nothing To Worry About (at Least In Australia)
There is no evidence that HFT causes spikes and crashes. Actual evidence says the opposite: by increasing liquidity, HFT reduces volatility.
Actual evidence from the guys who monitor these kind of things says nothing of the sort. I wish people would stop spouting this line about HFT and liquidity. Here is a relatively recent GOOG flash crash (April 22 2013) likely due to HFT (based on timespan and number of trades, number of orders placed per trade and number of exchanges involved).
Have We Hit Peak HFT?
HFT is a symptom of a deeply broken system. It brings liquidity, which is good, but it has tended to move the market in unreasonable (and sometimes dangerous) ways.
That is a bit simplistic as well. First, stepping in front of a trade because you can (1) see it before the other guy (due to having lower latencies in talking to the exchange or having priority 'fast' data feeds) and (2) quote using fraction of a penny increments as opposed to pennies for the 'regular' guys is not adding liquidity. In fact, from the way flash crashes happen you can see exactly how HFT does not add liquidity with a stock/future going bidless and crashing. Properly supplying liquidity would not allow for something like that to happen.
When talking about long-term stewardship of institutions, we really need to move away from unreasonable earnings expectations every quarter.
Who is we? The short-termism here is the market speaking. The idea of markets setting the 'right' price is highly dependent on your definition of 'right'. As the saying goes, markets can remain irrational longer than one can remain solvent (and bet on rationality). Nevermind the fact that people in the market have different types of interests which are not always aligned to long-term value. See corporate raiders, LBO, and so on - case in point, Icahn.
When the focus of the market is on ever narrowing periods of time, corporations simply cannot properly invest in the future.
That's not entirely the problem. When the upper echelons of the corporations receive stock options with short vesting periods (no, 5 years is not long term compared to typical investment horizons, and 5 years are not really that frequent) the motivation to invest in the long-term future is basically absent. Also, there are industries where that is simply not possible, as the prevailing conditions fluctuate too much.
Ultimately, stock/commodity/bond markets are about profit. There is nothing inherently wrong with that. The question for the rest of us is: what is the social value?
Indeed, profit is the key word. Social value is incidental, if at all.
So much for EU dmocracy
These last two days were really a proof that democracy in the EU is still a remote goal. To have the Council trump the Parliament twice in 2 days, and going flat against the interests of EU's own citizens, is sad.
While the decision that made /. front page, about software patents is bad enough, it still has a slim enough chance to reach a forced arbitration if enough MEPs decide theis votes should have some value when it comes to EU laws. But I truly am amazed of the (sheer ineptitude of the) decision to ratify the handing over of EU citizen's private information to the US. Not only the Parliament's decision that such a move is against EU laws weighted nothing, the foreign ministers hurried up to ratify the Council's decision, so no further approval in the Parliament is needed.
So much for the EU governments looking for their people's interests. Do they really believe that the US will give a damn about the privacy of some foreigners??? when on enough recent occasions the US showed their own citizens' privacy is expendable. And sure they'll just go out of their ways to ensure that all this data is never, ever, ever misused. Not now, not in 20 years. Riiiiight!
So, as expected, money talks the loudest in politics. And if it's foreign money ... why should a politician care? their own skin comes first, apparently. This shows democracy for what it truly is in the long term - innocent people sometimes wander into politics, but they don't stay innocent for long. Yeah, I know, voting is supposed to take care of that; so if any fervent defender of democracy would care to explain to me how would he/she vote when faced with only evil choices, I'd be glad to learn about the benefits of voting[*]. Until then, I maintain that democracy is trumped by human nature.
[*] for the record - communist countries in Eastern Europe were supposed to be democratic, too - at least on paper. They did even have the all-prized hallmark of voting. Guess what - it made no difference whom one was voting for, since the results were known from the beginning. And, as the US constantly seems to remind the world, money do count in an election - money dictate how much of an audience a candidate reaches. How many people would vote for a candidate that never had enough funds to make his/her better platform known? Democracy is truly a joke when pushed too far.
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Yay! first flamebait mod! that should teach me to post anything but pro-Apple comments on Apple articles. Why bother, actually - it's bad for one's health to criticize Apple on /. Worse than criticizing Linux, really - apparently using Linux keeps one's sense of humor up (hope it does keep mine)