top Ask Slashdot: Where Can You Get a Good 3-Button Mouse Today?
You might be able to: my Logitech Mx518 (at least with the software I have installed) doesn't seem to allow rebinding the two primary buttons, though, so it's not a sure thing. The OP can do what you suggest, or just ask around (on Reddit, user reviews, even send a message to Logitech).
top Barrett Brown, Formerly of Anonymous, Sentenced To 63 Months
Aside from the fact that that wouldn't work anyways (intent to link to the illegal material would be required, and that certainly wouldn't meet that qualification), the hyperlinking charges were dropped. Yeah, the Slashdot summary is a bit deceptive (absolutely shocking, I know).
top The Paradoxes That Threaten To Tear Modern Cosmology Apart
> What's more, there is an energy associated with any given volume of the universe. If that volume increases, the inescapable conclusion is that the energy must increase as well. So much for conservation of energy.
Why cant the energy just be less dense?
FLRW metric (which is what the equation that governs the cosmological expansion of spacetime) has a cosmological constant term in it, initially placed there by Einstein to maintain a steady state universe, but which we now know drives an accelerating expansion of the universe. This constant term is exactly that: a constant (negative) energy per volume of space. More space means more total energy.
However, TFS and TFA (I've only scanned the referenced paper, but that looks much more reasonable) are absolutely wrong about why this is a problem. It is a problem, but only in the sense of figuring out where it comes from (i.e. what exact mechanism drives the creation of this energy). The
fact that energy is not conserved violates no law of physics: in fact, general relativity doesn't conserve energy anyways, and the expansion of the universe certainly does not (even without the non-conservative nature of gravity).
See, the conservation of energy is a result of
Noether's theorem, which states that for any differentiable symmetry of the action of a physical system, there is a corresponding paired conservation law. For time symmetry, this is the conservation of energy. However, time on the scales of the universe is not symmetric. There was a beginning to the universe (which alone breaks the symmetry: you can't shift backwards in time more than ~13 billion years), and the universe as it is now looks nothing like it did 10 billion years ago. So we don't expect energy to be conserved in the universe as a whole (even if it is on local scales).
top Your Entire PC In a Mouse
Dunno what cables you're using, the HDMI cable hooked up to my monitor is only slightly thicker and stiffer than my mouse cable.
top An Open Letter To Everyone Tricked Into Fearing AI
you think it's absolutely impossible that could be achieved in say the next 500 years, considering what humans have accomplished in the last 100?
Absolutely impossible? No. But the problem is that we don't even know where to begin creating a true AI, which means we also know nothing about what threats it may or may not pose... so we also have no actual way to address those threats. All we have right now is pure, 100% complete speculation (no different from speculating about what would happen if we had FTL travel, or psykers, or met aliens). There are plenty of actual threats to humanity that really exist right now (or could be created with our current knowledge and technology), which makes worrying about something we know literally nothing about kind of silly.
top Linux Controls a Gasoline Engine With Machine Learning
Fuel injection and spark events only occur at the 10s of Hz scale (topping out at around 60 each per second). Even if you handle cam phasing and MAF sampling at 100 times that interval, you're still within the computational work load of a couple dozen MHz of instructions.
Aye. Now try controlling the engine and fuel injection system, and achieving combustion,
without using a spark plug. Because that's what the story is actually about. They're using compression-based ignition (like a diesel engine) rather than spark based ignition (like a conventional gasoline engine), which requires a detailed knowledge of the state of the engine at each cycle.
The research is only interesting because they are taking advantage of way overspecced processing power to approach combustion more granularly per event and trying to learn from each one and control the next. It only got press here because they used Linux (anything production grade would use QNX or similar).
Nah, it's interesting because it's an application of machine learning algorithms applied to an actual physical problem that might have real-world practical use (the whole Rasberry Pi/Linux angle is a side note in the paper just to show that the algorithm is fast enough for real-world application). A possible 30% fuel efficiency increase in all/some new cars? Car makers would certainly be interested.
top Who's Responsible When Your Semi-Autonomous Shopping Bot Purchases Drugs Online?
It's not okay, but it wouldn't be murder either. It would be manslaughter.
That depends. If you should have known the gun would have a significant chance of hitting someone, you could well be facing a full murder charge. Randomly shooting a gun in a field in the country? Probably manslaughter. Doing the same in a crowded shopping mall? Yep, that'd be murder. Likewise this bot was shopping randomly on a darknet that has a lot of illegal stuff for sale, and the creator would (absolutely should have, anyways) have known that, which means he would be legally liable for the purchases (if the government decided to press the issue).
top Experiments Create Particles Out of a Vacuum Using Neutrinos
(sigh) You're doing it wrong - that link you gave is the wrong one . The article the summary links to has a link to the correct (and non-paywalled) article at arXiv.org. Have a nice day :-)
The link the GP gave
is to the paper linked directly to by the summary (the direct link to the abstract), so some confusion is understandable. In the future, maybe make submissions discuss one and only one paper (or make it obvious they're two papers)?
top Red Hat Engineer Improves Math Performance of Glibc
It looks like the slowest paths of the transcendental functions were improved by a lot. But how often do these paths get used? The article doesn't say so the performance benefits may be insignificant.
From TFA, it sounds like the functions in question (pow() and exp()) work by first looking at a look-up table/polynomial approximation technique to see if the function can use that to get an accurate-enough value, then running through a series of multiplications to calculate the result if the table/approximation method wouldn't be accurate enough. Since this work improved the actual calculation part, my guess is that it will improve quite a few cases. TFA does say the lookup table method works in the "majority of cases", though it doesn't say exactly how big a majority, so it's hard to say exactly.
top How We'll Program 1000 Cores - and Get Linus Ranting, Again
The nature of the workload required for most workstations is non-uniform processing of large quantities of discreet, irregular tasks. For this, parallelism (as Torvald's correctly notes) is likely not the most efficient approach. To pretend that in some magical future, our processing needs can be homogenized into tasks for which parallel computing is superior is to make a faith-based prediction on how our use of computers will evolve. I would say that the evidence is quite the opposite: That tasks will become more discrete and unique.
Right, but we want to continue the "Moore's Law" speedup of processing year over year. And that simply can't happen with single core processing: clock speed is already near the physical limit (as in we would need to start violating the speed of light to increase it much further), and manufacturing process size can't continue shrinking indefinitely either, no matter how close we are to the actual physical limits there. So unless we invent entirely new computing systems (e.g. quantum computers), the only speed gains in the future will inevitably be from parallelization, and there are (for many cases) still massive speed gains to be made in that field, simply because the software was never designed for any parallelization at all. Granted, that'll hit a wall where you can't split tasks up anymore as well, but in many cases this process hasn't even
You're quite right about the graphics, though: the long-term future of graphics technology is probably ray-tracing, and that takes absolutely massive amounts of completely parallel CPU power.
top Vast Nazi Facility Uncovered In Austria; Purported A-Bomb Development Site
How on earth would you Godwin this? Comparing the Nazis to the Nazis is a bit redundant.
That's just the kind of thing Hitler would have said!
top Science Cannot Prove the Existence of God
Someone made up that supernatural/natural thing.
Yeah. Physicists. The term "physics" in fact literally means "knowledge of nature", i.e. knowledge of those things in the natural world (this is an old definition, of course, from back when physics was considered a philosophical discipline, but while the methods used in physics have changed the subject matter has not). As opposed to supernatural objects, which would fall under the purview of metaphysics and/or theology.
Science doesn't require that the phenomenon it studies be "natural." Only that they be observable and consistent.
Believe it or not, "observable and consistent" and "natural" mean almost literally the same thing (using the term "natural" to refer to "things in nature", not to natural vs. artificial: in any case, all artificial objects are at some level made up of natural stuff anyways). All natural objects are observable in some way (i.e. have observable properties: mass, volume, location, etc... something that can be quantified, in other words), and the word "nature" in one of it's oldest definitions in physics means "how something acts always or for the most part", i.e. it acts in a consistent fashion (not sure most modern physicists would even bother giving a definition of "nature", but when we speak of the "nature of an object", that definition is essentially what we mean). Supernatural objects, by definition, lack both (actually, having one generally (always?) means you have the other as well).
top Science Cannot Prove the Existence of God
Make sense. I had to use Vim once, and it felt like I was in Hell.
top Bill Gates Sponsoring Palladium-Based LENR Technology
Who published this "study" and how was it peer reviewed?
Snake Oil Monthly, peer reviewed by "homeopathic scientists". Obviously. Or (since Rossi is a tiny bit subtler than that... though only a tiny bit) the """ Journal of Nuclear Physics"""*, which (in a startling coincidence) is "published" by Rossi himself (if posting something to a blog counts as published). It may well have been peer reviewed, but of course since Rossi is a fraudster, not a scientist, the peers in this case... well, lets just say they probably have more of a theoretical degree in physics than a degree in theoretical physics.
*As a side note, this is a good example of why simply because something was "published" in a respected-sounding journal does
not mean it's actually trustworthy. I could form the American Journal of Renowned Physics Breakthroughs tomorrow and publish the flimsiest of flim-flam in it. Anyone could.
top US Navy Sells 'Top Gun' Aircraft Carrier For One Penny
All ships of that class have been decommissioned/scrapped already, so any details of the interior are irrelevant, as it's no longer a design in service. Knowing where to hit to sink a ship that isn't being used anymore isn't exactly useful military knowledge.
top UK Man Arrested Over "Offensive" Tweet
You are free to express you opinion no matter how nasty but it must be expressed as an opinion.
In the UK, this is simply and completely not true, and the entire point of the news story. The UK "Communications Act 2003",
section 127 (1) states (and I directly quote):
A person is guilty of an offence if he—
(a)sends by means of a public electronic communications network a message or other matter that is grossly offensive or of an indecent, obscene or menacing character; or
causes any such message or matter to be so sent.
So yes, sending an offensive message in the UK is a crime, no matter if the message is true or not.
top Deflating Claims That ESA Craft Has Spotted Dark Matter
However, for some reason unknown to me, the visible matter in our solar system perfectly describes how the planets orbit the sun, how the moon orbits the earth, and how hard I hit the ground when I try to fly. So where is this dark matter, all this extra gravity? Shouldn't I hit the ground a lot harder than we can explain just based on the mass of our planet?
It's because dark matter only interacts gravitationally. See, normal matter clumps up into planets and stars because it sticks to other particles, and loses energy from collisions, causing it to collapse over time into locally dense spheres (planets, stars, black holes, etc.). But dark matter doesn't: it just passes through itself (mostly: it may interact through the weak force, but only very very very rarely if so, not enough to clump up). That means it doesn't form local regions of high density. On the other hand, an object immersed in a more or less uniform sea of matter (of any kind) won't notice any gravitational effects, because it's being pulled in all directions equally (for example: you'd be weightless at the center of the Earth. Dead from the pressure/heat/lack of air, but weightless). So, we can float through a sea, even a fairly dense one, of dark matter and notice nothing at all. Now, there is an non-uniformity in this dark matter "sea": there is more on the side of us towards the center of the galaxy than there is on the other side, but that pulls the entire solar system uniformly, accelerating it in it's galactic orbit, and that effect we do in fact see.
about a month and a half ago
top Man Caught Trying To Sell Plans For New Aircraft Carrier
It's arguably entrapment, and whether or not the guy will end up with a criminal conviction I don't know (IANAL, certainly not on matters of treason), but this has nothing to do with "policing". They aren't looking for criminals at all. It's essentially a penetration test: they generally try to only give out security clearances to more or less trustworthy folks, but some people with clearances are going to be willing to give up classified information for money. The way to find those people is to offer them money. This sort of thing is routine practice in many different areas. It's quite common, for example, for companies to send out fake phishing emails so they can identify people who might fall for them. Usually, this sort of "entrapment" results in firing or training, but when you're dealing with classified information, criminal prosecution is a pretty obvious step.
Generally, being stupid and greedy isn't a crime, but when you work in a field where being stupid and greedy like this can easily get people killed, and you
know that, and signed a document to that effect, well, then when you act stupid and greedy, you won't get much sympathy from me if the government tries to throw you in jail. about a month and a half ago
top Aliens Are Probably Everywhere, Just Not Anywhere Nearby
Unfortunately the Drake equation is worthless even for that purposes, as several terms in it cannot be estimated with any accuracy at all, and may in fact never be able to. You can't for example, extrapolate the probability of life evolving on a given planet when you only know of a single example of life evolving (extrapolation requires
at least two instances). That leaves 4 terms in the Drake equation (fraction of planets that develop life, fraction of living planets that develop intelligence, fraction of those that end up sending signals into space (though those latter two should probably be condensed into a single term), and length they send out said signals) that cannot be estimated with any accuracy until we discover some instance of them. Which, rather ironically, means the Drake equation is worthless for any kinds of actual predictions unless we actually discover intelligent life, at which point the entire problem it was meant to illustrate becomes kind of moot (because we'll then know the answer that yes, there definitely is other intelligent life in the universe).
You can sort-of put weak upper bounds on (at least some of) those terms, but we're a long way from being able to do that.
top Physicist Kip Thorne On the Physics of "Interstellar"
Humor aside, relativity and thermodynamics have been proven at both the largest and smallest scales that humans have been able to observe, and at every level in between.
This is half completely wrong. Thermodynamics by definition does not apply to small scales, only to bulk systems. Hell, a small system of particles can (and in fact quite often will) easily violate the laws of thermodynamics. They're almost meaningless at small (i.e. a few dozen atoms) scales, because they're purely
statistical laws. Even a large system can, in principle, violate the laws of thermodynamics, but only for extremely brief periods of time, and with a likelihood that approaches zero for macroscopic (order of 10^23 particles) systems.
Secondly, the behavior of relativity at very small scales is currently unknown. Reconciling general relativity with quantum mechanics requires quantized gravity, and all current attempts to describe that mathematically have failed. This is a problem in either very small scales (i.e. Planck lengths, which to be fair haven't been observed and probably won't for quite some time), or in extremely large gravitational fields, such as that created by black holes, which we have (indirectly) observed. Both relativity and thermodynamics work great in their relative domains, but both of them have known domains where they collapse. For thermodynamics that doesn't really matter (it's constructed to only be true for bulk systems), but it's a pretty big issue for relativity, and suggests there is a significant gap in our knowledge.