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Comment: Re:Mostly done by 1985... (Score 3, Informative) 126

by slew (#47524519) Attached to: Black Holes Not Black After All, Theorize Physicists

Gravitational time dilation affects the falling object, not the observer. If you claim that if I throw a baseball at a sufficiently large star then I'll eventually see the baseball slow down as it approaches it, then you need an explanation for the repulsive force.

Actually you probably won't actually "see" it slow down, it will eventually red-shift to be invisible (which is actually slowing down). Gravitational time dilation makes an object an object approaching the event horizon of a black hole to appear to slow down, taking an infinite time to reach the event horizon.

Comment: Re:TripAdvisor (Score 1) 424

by slew (#47464681) Attached to: French Blogger Fined For Negative Restaurant Review

Of course 80% of the reviews suspiciously appeared after the lawsuit was publicized (10% of the most recent reviews are in English instead of French is another clue). The old ones are mostly mediocre, but as you might expect the recent ones are mostly complaining about the lawsuit (and the recent ones posted after the lawsuit publicity appear to be perhaps a bit reality-challenged). Me thinks there might be more lawsuits on the way ;^)

There appears to be only 1/7 reviews on yelp that predate this event and appears to have the common qualities of a yelp review (you can read whatever you want into that assessment).

On the other hand, it appears to be just a generic pizza place in a rinky-dink (pop 7396) coastal town in France. What do people expect?

Comment: Re:No real surprise (Score 1) 708

by slew (#47458865) Attached to: People Who Claim To Worry About Climate Change Don't Cut Energy Use

Eh, I think Karl Schwarzschild is the name you're looking for...

Actually, I think the name you might be looking for is John Michell...

Nobody really knows who deserves the actual credit for INVENTING the name black hole, but Johnny Wheeler (for those that know, he was the Feynman before Feynman) certainly was the person to popularize the term.

Anecdotally, Mr. Wheeler claims to have heard it shouted out from the audience at a meeting Goddard Institute for Space Studies in New York in 1967, but it seems to have been popular for some time before that. In Jan 18, 1964, the Science News Letter about a meeting of the American Association for the Advancement of Science (AAAS) apparently had this quote:

According to Einstein’s general theory of relativity, as mass is added to a degenerate star a sudden collapse will take place and the intense gravitational field of the star will close in on itself. Such a star then forms a ‘black hole’ in the universe.

Perhaps even more importantly, a few French scientists objected to the term (because of it's dual meaning in French), but that objection probably sealed the deal on the name.

Power

People Who Claim To Worry About Climate Change Don't Cut Energy Use 708

Posted by Unknown Lamer
from the just-build-a-few-nuclear-reactors dept.
schwit1 (797399) writes with news that a UK study has found that folks concerned about climate change don't do much to conserve power at home. From the article: Those who say they are concerned about the prospect of climate change consume more energy than those who say it is "too far into the future to worry about," the study commissioned by the Department for Energy and climate change found. That is in part due to age, as people over 65 are more frugal with electricity but much less concerned about global warming. However, even when pensioners are discounted, there is only a "weak trend" to show that people who profess to care about climate change do much to cut their energy use. The findings were based on the Household Electricity Survey, which closely monitored the electricity use and views of 250 families over a year. The report (PDF), by experts from Loughborough University and Cambridge Architectural Research, was commissioned and published by DECC. High power use doesn't have to be dirty: Replace coal, methane, and petroleum with nuclear, wind, solar, etc.
Graphics

AMD FirePro W9100 16GB Workstation GPU Put To the Test 42

Posted by Unknown Lamer
from the more-power dept.
Dputiger (561114) writes "It has been almost two years since AMD launched the FirePro W9000 and kicked off a heated battle in the workstation GPU wars with NVIDIA. AMD recently released the powerful FirePro W9100, however, a new card based on the same Hawaii-class GPU as the desktop R9 290X, but aimed at the professional workstation market. The W9100's GPU features 2,816 stream processors, and the card boasts 320GB/s of memory bandwidth, and six mini-DisplayPorts, all of which support DP1.2 and 4K output. The W9100 carries more RAM than any other AMD GPU as well, a whopping 16GB of GDDR5 on a single card. Even NVIDIA's top-end Quadro K6000 tops out at 12GB, which means AMD sits in a class by itself in this area. In terms of performance, this review shows that the FirePro W9100 doesn't always outshine its competition, but its price/performance ratio keep it firmly in the running. But if AMD continues to improve its product mix and overall software support, it should close the gap even more in the pro GPU market in the next 18-24 months."

Comment: No... (Score 2) 144

by slew (#47417557) Attached to: Physicists Spot Potential Source of 'Oh-My-God' Particles

That's kindof BS...

Mass doesn't expand infinitely nor is there a speed threshold of energy as far as our current understanding of physics goes... This is a simplistic bookkeeping trick that attempts to account for limited acceleration near the speed of light (since F=ma, for a given force, you get less "a" if you somehow fudge 'm' to increase as you approach the speed of light). General relativity explains this much better by having any mass or energy actually distort space time so that you don't ever need this overly simplistic bookkeeping trick (which has unfortunate anomalies like rest-mass and photons having no rest mass, but momentum).

In your own frame of reference, you can accelerate as long as you have the energy to do so. The problem is that from an external observer's frame of reference despite your apparent acceleration from your frame of reference (you think you are going faster and faster), your time dilation factor relative to the observer means it doesn't observer you exceeding the speed of light, The observer thinks your acceleration (dv/dt) is asymptotically approaching zero as you approach the speed of light. Even though you have been accelerating all the time, you don't teleport relative to the observer (although the observer will think you were moving very, very fast, but not faster than light), but if you were to get back to the same frame of reference as the observer, you will have noticed your observer has experience quite a bit more time than you have (this is the origin of the twin paradox of special relativity).

From your special relatively frame of reference, you moved very fast (because you experienced less time for the distance you appeared to travel), but from the observers point of view, more time was experienced, so the velocity never exceed the speed of light. The way this is book-kept for is usually lorenzian length contraction. As you approach the speed of light the distance you observer to traverse over a unit of your time is shorter, so when you divide the distance by your time, you also don't observe that you went faster than the speed of light.

Of course if you could somehow create say a warp drive (or some other FTL transport), to a third party observer, you might appear to be in two places at once, and/or it would appear like time transport, but many folks thinks it is really possible to do this. Creating such a warp disturbance (actually warping space time around you) would likely require a very, very large, but not infinite amount of energy to maintain a negative energy-density around you. It is hypothesized you could not do this w/o some sort of pervasive zero-point energy source or creation of a type of exotic matter to sustain the required region of negative energy-density.

Comment: Re:actors and athletes get paid at 13 (Score 3, Informative) 253

by slew (#47411665) Attached to: US Tech Firms Recruiting High Schoolers (And Younger)

Yes, but 13yo actors and athletes need special work permits and still need to attend to school whilst working.

In many localities, they must have part of their earnings put directly into trust funds (e.g., a Coogan account in California) so neither they or their parents will blow all the money on something, or up something...

Also, when the sums of money are large enough, many reputable employers require profession agent representation (so they don't claim to have been taken advantage of and sue later).

I doubt any of these internet companies are doing any of these even minimal best-practices/policies for these 13yo nerds (and these minimal things don't even prevent the Lindsey Lohans and Tracy Austins of the world)...

Comment: Re:GPS on Mars (Score 1) 104

by slew (#47408073) Attached to: ESA Shows Off Quadcopter Landing Concept For Mars Rovers

It isn't about capability, it's about € the ESA can't afford to put up Galileo, l suspect that putting up a global navigation system around Mars would be a bit cost prohibitive for this application.

Part of the problem with deploying a GNS is that you need ground uplink station for reference correction (inertial clock correction and fault detection isn't generally sufficient for good long term accuracy). At least they might have less of a problem with ionospheric propagation delay (Mars still has a single layer of ionosphere, though, and since Mars doesn't have much of a magnetic field, it's subject to lots of solar wind effects, so very little is known about correcting for it).

No worries, though, I doubt the ESA isn't thinking about a Martian GNS for this, it's just a research project which happened to use GPS for coarse location. The real technology uses a vision-based navigation supplemented by a laser range-finder and barometer.

Comment: The light stuff works totally differently (Score 3, Informative) 71

by slew (#47403397) Attached to: Tractor Beam Created Using Water Waves

FWIW, this paper talks about doing this with light (in the context of micro-manipulation). Doesn't look like we will be using this for any star-ship sized objects in the near future...

The basic idea is that you use a light with a specific profile to stimulate the object you want to attract in a way that causes a scattering field such that there is a net force backward to the emitter (it only works if the amount of net forward momentum of the light is relatively small compared to the scattering).

The water stuff referenced by this article works on a completely different principle, though as described here.

They are similar in that they originate with a wave generator, also hitting the target at a glancing angle is a way to achieve the necessary conditions and both provide a net attractive force (aka tractor beam), but the physics is totally different.

Comment: Re:Would allow moving the cockpit. (Score 1) 468

I'll be [sure] some passengers would like that prime real estate.

In a commercial B747 (if you can find one still flying), where the cockpit would be on a single-decker plane, there is generally a passenger cabin with windows all the way to the nose (although no windows that face forward)... Although that used to be prime real-estate, it is generally relegated to economy-plus (business class and first class upstairs) as the market for premium seating has reduced...

FWIW, there's probably more to be gained by eliminating passenger windows like this Spike aerospace design, although I'd be interested to see how they get around the simulated parallax problem with their proposal...

Comment: Re:Scientific research never got anyone anything (Score 2) 225

by slew (#47378777) Attached to: Senate Budgetmakers Move To End US Participation In ITER

Actually, much of the goals of ITER isn't so much to research fusion (as much of that was done in the earlier projects like the TFTR project @Princeton, similarly the like the attempts to make Thorium fission reactors like MSRE wasn't to research fission).

ITER is basically a big material science / engineering experiment to see if it is possible to build a plasma containment vessel that withstand the neutron flux and estimate how much it will be to decommission such a beast thing later (after it becomes totally radioactive). Of course there's always the net energy problem (since TFTR never got to net energy), but for tokomak type reactors, this is complicated by magnetic containment power efficiency (can't let that plasma touch the wall) and the diverter architecture (how you clean the plasma of fusion products w/o shutting off the reactor). I don't think ITER is doing too much new research in this area (apparently mostly borrowing from other efforts like MAST, JET, Alcatore, etc)...

With ITER, apparently they aren't making great progress on any of these problems. Sometimes you just have to put a project out of it's misery and start over with a clean slate. I think ITER may have reached that point. Unfortunately, that means the follow-on DEMO project (the attempt to scale the ITER reactor to per-commercial size instead of research size). But obviously, if you don't have something that works, you can't scale it and everything may be a bit premature...

Comment: The mishmash of DNA is to be expected (Score 2) 198

Since mitochondrial DNA is passed on by the mother, this means that it's still possible that some guy's going around getting bears, dogs and horses pregnant. The human DNA match, of course would be from a woman getting pregnant by a bear.

The mystery continues.

Comment: slippery slope argument (Score 2) 1330

by slew (#47355789) Attached to: U.S. Supreme Court Upholds Religious Objections To Contraception

Everyone uses the slippery slope argument in politics and the media... Even on /.

IMO, this whole fuss on Plan B is kind of a crock. It costs about $50 at a drug store (you can get it over the counter and buy it with a downloadable $10-off coupon) with a $35 generic available. Comparatively, a birth control pill runs anywhere from $10-$100 (but mostly commonly hovers around $20 and mail order saves you about $5) and generally requires a prescription to be covered in a health plan (because they will make you mail order it to save money).

Don't know how often people would need to fork over for plan B out-of-pocket in a year, but I think if a person needed emergency contraception more than a couple times a year (out of 12 months) seems like that person probably should be looking at some other form of birth control, maybe? Of course if someone else is paying for it and such a person didn't have a moral problem with it, maybe people don't really care (but people *should* care because currently existing emergency contraception has quite a few serious side effects for those under 25 or have a high BMI which described a large part of the userbase for these drugs, but of course that's not part of the marketing material and no prescription or consultation is required).

FWIW you can't get aspirin/acetaminophen, cold symptom relief, or acne medicine covered as an over the counter medicine as part of a health plan (unless you get a prescription), but because of politics, emergency contraception has a special carveout in this market. Of course the generics available outside the USA (e.g, I-pill) is only about $10 a dose (about the same price as "emergency" Nyquil or Sudafed which your insurance company won't cover). On the other hand, insurance companies would probably gladly cover it gratis (since it's cheaper than pre-natal/pregnancy for them) and they already have this exact legal carveout for non-profits, but it's more fun to raise a stink and energize the base (on both sides of the aisle)...

Comment: Ask a silly question... (Score 1) 211

What causes him to keep doing this?

Money.

But more seriously, this is one of the problems with electing a president with a short political CV/resume. His circle of trust doesn't have the critical mass of folks that can survive a vetting process (any than could have already got their job and gotten out after 4 years), so he has to rely on getting suggestions folks in an extended political operative/Washington insider circle which only knows people looking for a job from the pool perpetual bureaucratic lobbyist ruling class that's pretty much bought and sold themselves to the highest bidders...

"Love may fail, but courtesy will previal." -- A Kurt Vonnegut fan

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