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Comment Re:Wow (Score 4, Informative) 117

Negative temperatures are actually a pretty well-defined and real thing, but that's just because of the way we define "temperature" in thermodynamics, which is not always exactly the same as what we think of as temperature in everyday life. The short explanation is that temperature (T) is the rate of change of energy (E) with respect to entropy (S) (in math: T=dE/dS). If I have a system that is bounded from above in energy (i.e. a maximum energy the system can reach), I can get negative temperatures. Simple example: let's say I have a system of particles, each of which can be in two states, a state with more energy, and a state with less energy. The entropy is the number of different states the *entire* system can be in, so if the system is in a minimum energy state (i.e. every particle is in the lower energy state) I have a minimum entropy system (every particle in the same state means I only have 1 possible state for the entire system). Likewise, in a *maximum* energy state, all the particles are also in the same state (the higher energy state), so I also have minimum entropy. Maximum entropy occurs when the energy is right in the middle between these: half the particles are in the higher energy state, half are in the lower energy state, so the entire system has the most possible configurations. So, if the system is in that state, and I add a bit of energy to it, I decrease the entropy (as there are fewer particles in the lower energy state and therefore fewer possible configurations). That means dE/dS is negative (since S goes down, so dS is negative, while dE is positive), so you get negative temperature.

In every day life, systems typically aren't bound from above, and also any particles in higher energy states like that will fall into lower energy states and release energy (this is exactly how a laser works, incidentally), so you only get negative temperature in carefully constructed systems.

The negative mass term in this case, however, is a negative effective mass (not a real mass) term that occurs in a group velocity (which is not the real velocity of particles in the system) dispersion relationship. Not to say the results aren't interesting: they are, they're just... well, not really negative mass at all.

Comment Re:Wow (Score 5, Interesting) 117

This sounds actually groundbreaking. Does anyone have more details? Were the authors trying to generate negative mass or was this an unexpected side effect? Obviously this is going to require some replication, but I'm excited.

That's because the headline is some of the worst sensationalistic tabloid journalism level garbage I've ever read. They did not observe "negative mass". They created a system wherein, under specific circumstances, part of the system behaved as if it mathematically had negative mass. Note that the entire system and every part of it individually still has positive mass: however, because of the way the system interacts with itself, when you do very specific things to it, parts of it can act (when taking very specific behavior) as if they had negative mass.

The headline and summary are the equivalent of saying "man travels through space safely without spacesuit on!", without mentioning he's inside a spaceship.

Comment Re:Lies, damn lies, and statistics (Score 1) 356

You are assuming that there would be a perfect 50/50 distribution of the was no discrimination, but you have to account for those getting exactly the same offer as well. No one sits down and calculates a candidate's precise worth to the cent,

I dunno what accounting they did, but the plot in the report clearly splits the population into 63% offered less, 37% offered more. It looks like they used an average value for the salary offers.

Comment Re:A purpose built chip (Score 4, Informative) 91

It is optimized for massively parallel low-precision matrix operations, which is useful not only for neural nets, but also simulation of physical processes like CFD, weather prediction, climate models, computational chemistry, etc.

Maybe, but I doubt it. It's far too low precision, for one thing: 8-bits doesn't get you very far in any of those fields (you typically want at least 32-bit FLOPS for those, and quite often 64-bit precision is required, as numerical errors accumulate exponentially in a chaotic system), and they're really not even big matrices (just 256x256). Really the only place this kind of thing would excel is signal processing, which is basically what they're using them for.

Comment Lies, damn lies, and statistics (Score 4, Insightful) 356

Hired's data shows that 63 percent of the time women receive lower salary offers than men for the same job at the same company,

That sounds awful, till you realize that from simple statistical fluctuation you'd expect that number to be 50 percent, in which light 63 percent seems to indicate some trend, but not nearly as big a one as the writer clearly intends to signify. How large is the average fluctuation? What's the probability women could have gotten such offers by chance (which would require knowing for e.g. the sample size, which, speaking of, that doesn't seem to be given in the report)? You know, anything that might reveal the statistical significance of the findings, which seem to be entirely absent from the report and without which raw numbers are almost entirely meaningless.

with white women offered 4 percent less on average, and women more broadly offered up to 50 percent less in the most extreme examples.

The report (linked in the article and here) says the average is 4% for all women. Also, "up to 50% in the most extreme examples" means "we found 1 case where that happened", which, again, you'd expect (in fact, you could probably find some extreme examples where a man was offered that much less than a woman), or at least, you'd *probably* expect (can't say for sure without knowing the variance of the job offers, which I supposed you could extract from the chart, but doesn't seem to be given in numerical form). 4% also just happens to be the average amount less women ask for than men. They also don't (AFAICT) look into issues like time taken off career for maternal leave (which, sorry, means you're going to be worth less due to not having been able to keep up with current developments, it sucks, but life choices have consequences), hours worked (statistically, men tend to work slightly longer hours than women: IIRC it's something like 8.4 vs 7.8 per day, but no clue if that is true in tech or not), etc. etc.

I should be clear: I'm not saying there isn't sexism in tech. There sure as shit is, for a lot of reasons, just like there's ageism, racism, religious discrimination, and a bunch of other -isms and -tions. But biased, politically motivated, and downright misleading articles like this one really aren't the way forward.

Comment Re:Develop a MOBILE GPU, yes? (Score 1) 148

There are a few things that mobile GPUs do to favour compute over off-chip data transfer because it saves power, but generally phone, tablet, and laptop GPUs are not that different other than in the number of pipelines that they support.

Well, aside from a massive difference in performance level and feature support. There's a reason Intel (despite actually making integrated desktop GPUs) doesn't try to compete with nVidia or AMD for the discrete market: modern desktop GPUs are very nearly as complicated as modern CPUs (in terms of transistor count, actually vastly more so, by a factor of 10-20 or so).

Comment Re:Wait... bad summary? (Score 3, Informative) 209

The official Georgia Code is the copyrighted code with the annotations. Anything without the annotations is unofficial.

They publish an official code with annotations, but the official statutory law with official numbering is available for free online (here). And the annotations (by law) do not carry the force of law (as that *would* make them uncopyrightable, as the linked decision points out). In short: the summary is not only clickbait, it's actually wrong. GA law is 100% completely free and available to all with no copyright restrictions.

Comment Re:Some privacy is more equal than other (Score 5, Interesting) 470

a definition that is meaningful in cases like the murder of a pregnant woman?

There is a subtle detail being missed here. The murder of a pregnant woman is certainly not at the woman's consent. That's the difference. An abortion is the woman's choice. A murder is not. Glad I could clear that up for you.

You completely missed his point, so hard in fact I suspect it was a deliberate choice to misunderstand what he was saying. What he was saying was that a fetus, unborn child, or hell, a fully born child (or adult), must be legally and/or morally recognized as a human by some definition as some point in time, and at that point it should be afforded legal protection as a human being. In point of fact, under federal law, an unborn child is recognized as a human if it is the victim of a violent crime. "The woman's choice" is completely irrelevant to the question, for the same reason a woman can't simply choose to kill a 6 month old, because everyone recognizes that a 6 month old is a human person, and one person cannot choose to kill another just because they feel like it.

Comment Re:So to sum up (Score 1) 656

Most BDSM practitioners align "SJW". These are conservative values that kicked him out.

No, it wasn't. He was kicked out because his sexual proclivities include the domination of women, specifically. To quote Buytaert word-for-word:

In the end, I fundamentally believe that all people are created equally. This belief has shaped the values that the Drupal project has held since it's early days. I cannot in good faith support someone who actively promotes a philosophy that is contrary to this. The Gorean philosophy promoted by Larry is based on the principle that women are evolutionarily predisposed to serve men and that the natural order is for men to dominate and lead.

You are correct that traditionally it'd be conservatives making a stink about someones sexual proclivities. That has changed, and is no longer true (well, never really was for some people, like the radicals who think that all sex between men and women is rape). Nowadays, nominally "liberals" are also opposed to certain kinds of sexual behavior, if such behavior doesn't fall into their acceptable category. They usually define "acceptable" different than conservatives, though in this case they both more or less agree.

Comment Re:While its not my cup of tea (Score 3, Interesting) 656

No, it's not new. Americans have been acting like this for a long time with all that puritan outrage bullshit despite being the land of commercial sleaze.

It's not new, but what is (fairly) new is that it's now coming from the nominally "liberal" and "progressive" political spectrum in America. It's the Horseshoe effect. Same reason many people on both sides of the political spectrum oppose prostitution: conservatives oppose it because they believe exploiting women for sex is immoral, and liberals because... well, actually, the exact same thing, really.

Comment Re:Please stop (Score 1) 272

Correct. It needs to be addressed. And putting it on the front page of tech sites keeps it from getting pushed to the side like it has been for far too long.

Or putting it front and center on tech sites might cause women who would otherwise be interested in going into tech fields to avoid them, because they don't want to go into a field where they think they will be discriminated against, thus leading to fewer women in such fields, thus leading to more accusations of sexism in those fields, and so on the circle goes. If I was a cynic (well, more of a cynic), I might even think that all these "tech is sexist!" stories are deliberately intended to keep women away from STEM, so that the appearance of sexism can continuously be used as a drum to rally political support. But I'm not quite that cynical: rather, I think it's just that people are more interested in appearing to solve problems than in actually solving them (which, to be fair, is definitely not a new phenomenon).

Comment Re:Loss of control (Score 2) 265

The issue here is that the producers of unsavoury content are being supported by income provided by the advertisers.

They probably don't really care about that either. What they care about is not being associated in the public mind with such socially unacceptable content, and as a plus by pulling their advertising dollars they can gain free advertisement from the news stories about pulling their ads.

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