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Comment: Re:Pay up and quit whining (Score 1) 372

by Baloroth (#48895241) Attached to: 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).

Comment: Re:And now... 3... 2... 1... (Score 3, Insightful) 109

by Baloroth (#48881751) Attached to: 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).

Comment: Re:"inescapable conclusion" (Score 4, Informative) 228

by Baloroth (#48871779) Attached to: 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?

The 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).

Comment: Re:"Forget about the risk that machines pose to us (Score 4, Insightful) 227

by Baloroth (#48825881) Attached to: 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.

Comment: Re: Is that engine even running? (Score 1) 89

by Baloroth (#48781619) Attached to: 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.

Comment: Re:Whoever is in physical possession of the drugs (Score 4, Informative) 182

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).

Comment: Re:Horrible Summary (Score 1) 86

by Baloroth (#48731195) Attached to: 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)?

Comment: Re:How much benefit? (Score 4, Informative) 226

by Baloroth (#48721117) Attached to: 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.

Comment: Re:Torvalds is half right (Score 1) 449

by Baloroth (#48717721) Attached to: 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 started.

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.

Comment: Re:Basic tenets of science (Score 1) 755

by Baloroth (#48701885) Attached to: 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).

Comment: Re:Rossi (Score 3, Informative) 183

by Baloroth (#48676143) Attached to: Bill Gates Sponsoring Palladium-Based LENR Technology

Who published this "study" and how was it peer reviewed?

I'd guess 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.

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