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Comment: History of issue; Calculation not so relevant (Score 4, Informative) 356

by cb123 (#47986419) Attached to: Physicist Claims Black Holes Mathematically Don't Exist

While this calculation may help convince about some aspects of some arguments, it isn't necessary for the headline claim. There was always an old issue non-formation (or more accurately partial realization in finite-time or general paradox/etc) because of the coordinate singularity at the event horizon (time slows to a stop). There is even a book called Frozen Star by Greenstein from the 1980s if you are interested in the history of this.

The reason what the article of this thread says may cause controversy or confusion is because of the cultural way the resolution of the original issue got converted into a "talking point"/recurring example/"de-confused". In free falling coordinates, crossing the event horizon is no more special than walking across Earth's North Pole. There is no "problematic" infinity until the actual center point (which is what the Hawking-Penrose singularity theorem is about, but that theorem in essence assumes non-evaporation). That theorem itself was in response to speculation of some process intervening to "bounce" collapsing stars and censor black holes from the universe.

All these statements are fine and still correct as far as they go, but one has to be careful about the background assumptions embedded in analyzing things in free fall coordinates. A long history of poo-poo'ing the coordinate singularity or some hypothesized bounce process as "unreal" or "unphysical" led to a tradition of always analyzing things in free fall coordinates (as the arXiv paper in the OP does!). The validity of this transform does have implicit requirements, just not in the pure math of the general relativity transforms but in the physical context. E.g., it requires an infinite background future (i.e. no Big Crunch) which seems to be implied by data these days but was in great doubt for decades. It also assumes a non-evaporating situation which has been in doubt since the mid-1970s with Hawking Radiation.

Here's the important point which I cannot emphasize enough: WHAT ACTUALLY TRANSPIRES IS REFERENCE-FRAME INDEPENDENT. At some (maybe far) future time, a mass concentration is either there or it isn't. Period. Reference frames change observed rates/the clocks/positions maybe but not the actual core situation. If a distant, non-freefalling observer can see a Black Hole evaporate to nothing in a finite-time, then at the end of the day [ or the hole ;-) ] it will have taken less time to evaporate than to form in both the freefalling frame and the distant observer frame. That is just another way of saying it just didn't finish forming. That's it.

People have been speculating about micro-black holes evaporating into nothing ever since Hawking's initial result. In that light there is no news younger than 40 years old here.

To be sure there are some specific dynamics to be modeled here and what this paper does is model them in free fall coordinates. All those details are surely important to pro physicists. The zinger headline of non-formation doesn't rely on such details. It only relies upon any mass-energy transfer from within the hole to a great distance away and enough time in the heat death to have evaporation be the dominant process (or else a small enough black hole that it doesn't need much time). Hawking Radiation is but one such process, though a theoretical one. Most think (on similar general theoretical grounds) that any quantum gravity will have ways for strong gravitational fields to decay. So, it seems likely that there will be some process, but sure, sure, evidence is needed, too.

Logically, though, reference frame independence of what actually happens means that any argument against non-formation is translatable to an argument against Black Hole decay. Contrapositively, any argument for black hole decay is an argument for only incomplete black hole formation. There may be possible glitches in last-moment of existence type stuff, but that truly is blind-leading-the-blind territory. I actually tried to raise this in 1988 with my freshman relativity professor but I don't think he understood my point and he mostly poo'poo'd about how Hawking Radiation would break down at the last moment of decay or something.

+ - How To Explain Big Data To A 5th Grader 1

Submitted by Nemo the Magnificent
Nemo the Magnificent (2786867) writes "What do you say when your 10-year-old asks you, 'What is big data anyway?' Daria Hutchinson works for a big-data analytics software company, Platfora. She thought a minute and said, 'I'm going to explain big data as it relates to your favorite online game, Fantage.' (For the uninitiated, this is a utopia of young girl pursuits.) Here's a little of how the conversation went. 'So the first thing about big data is that it is big. ... Hadoop solves the size problem of big data... If your data gets too big to fit on your computer, you can just add more computers. It grows as your data grows. ... The second thing about big data is that it comes in all different formats. ... The third thing about big data is that it can come in very fast at times. ... With big data, you have to be fast at capturing the data, but you also have to be fast at reading it. Nobody likes to wait. For some questions, a little bit of waiting is acceptable. For others, answers are needed right away.' Hutchinson captures the problem space pretty well, in terms a 5th-grader can relate to."

+ - SPAM: Work hours being cut for Obamacare employer mandate

Submitted by Randy Davis
Randy Davis (3683081) writes "We've been warn by this but few have listened and a lot of people have praised Obama care, now we are feeling the effects. The employer mandate was not about requiring businesses to offer health insurance, it is about a revenue collection scheme all along. Why would they make the tax only a fraction of the cost to actually offer insurance. It is clear that they want to make paying the penalty the most cost effective option.

"Scores of businesses have, in fact, begun to reduce hours for part-time workers to fewer than 30 hours per week, the Post noted — which is Obamacare's definition of full-time employment — so they don't have to offer health insurance coverage that has actually skyrocketed for tens of millions of Americans since the law was passed.""

Link to Original Source

+ - Philips Ethernet-powered lighting will transmit data to mobile devices via light->

Submitted by llebeel
llebeel (2761081) writes "Philips has showed off its Ethernet-powered connected lighting for offices of the future, which can transmit data to mobile devices through light via embedded code.
Arriving in the form of LED "luminaires", Philips' connected office lighting will aim to not only save businesses money on energy costs, but also serve as a means of providing information and data about the general running of a building, transmitted through light, to improve the overall efficiency of business infrastructure."

Link to Original Source

+ - Quadriplegic Man Uses Thoughts To Move His Hand->

Submitted by Diggester
Diggester (2492316) writes "We have been hearing all about prosthetic organs for quite a while but what if we told you it’s possible to move your hands and fingers with the help of your thoughts? That’s exactly what Ohio State University and Battelle researchers have been able to achieve with their brain implant. Thanks to them, a quadriplegic man is now able to move his hands and fingers with his thoughts. Meet Ian Burkhart who is paralyzed and was a participant in the clinical trial Neurobridge conducted by the Ohio State University."
Link to Original Source

+ - Happy software developers solve problems better.->

Submitted by HagraBiscuit
HagraBiscuit (2756527) writes "Researchers from the Faculty of Computer Science, Free University of Bozen-Bolzano, Bolzano, Italy, have quantified and analysed affective mood index against objective measures of problem-solving effectiveness for a group of software developers.
From report abstract:
"The results offer support for the claim that happy developers are indeed better problem solvers in terms of their analytical abilities. The following contributions are made by this study: (1) providing a better understanding of the impact of affective states on the creativity and analytical problem-solving capacities of developers, (2) introducing and validating psychological measurements, theories, and concepts of affective states, creativity, and analytical-problem-solving skills in empirical software engineering, and (3) raising the need for studying the human factors of software engineering by employing a multidisciplinary viewpoint."

Graziotin D, Wang X, Abrahamsson P. (2014) Happy software developers solve problems better: psychological measurements in empirical software engineering. PeerJ 2:e289 http://dx.doi.org/10.7717/peer..."

Link to Original Source

Comment: Why do you think $.02*12/year/GB is cheap? (Score 2) 335

by cb123 (#46475623) Attached to: 1GB of Google Drive Storage Now Costs Only $0.02 Per Month

A 4TB drive is under 200 USD from several vendors. That is only $.05/GB. So, at 0.24/yr. This is 5..10X more expensive than commercial off the shelf home drive space assuming you have to buy a new drive every 1-2 years. That time figure is pretty conservative.

So, yeah, you maybe cloud storage gives you some replication, and the syncing of that replication costs some amount of money for bandwidth. How much extra that reliability costs really depends on the data dynamics, though and isn't as easy to estimate.

Also, 5..10X more is just about the ratio of SSD storage to magnetic disks. SSD is considered "relatively expensive storage" by most people I know.

The Media

What Does It Actually Cost To Publish a Scientific Paper? 166

Posted by Unknown Lamer
from the one-trillion-dollars dept.
ananyo writes "Nature has published an investigation into the real costs of publishing research after delving into the secretive, murky world of science publishing. Few publishers (open access or otherwise-including Nature Publishing Group) would reveal their profit margins, but they've pieced together a picture of how much it really costs to publish a paper by talking to analysts and insiders. Quoting from the piece: '"The costs of research publishing can be much lower than people think," agrees Peter Binfield, co-founder of one of the newest open-access journals, PeerJ, and formerly a publisher at PLoS. But publishers of subscription journals insist that such views are misguided — born of a failure to appreciate the value they add to the papers they publish, and to the research community as a whole. They say that their commercial operations are in fact quite efficient, so that if a switch to open-access publishing led scientists to drive down fees by choosing cheaper journals, it would undermine important values such as editorial quality.' There's also a comment piece by three open access advocates setting out what they think needs to happen next to push forward the movement as well as a piece arguing that 'Objections to the Creative Commons attribution license are straw men raised by parties who want open access to be as closed as possible.'"

Comment: Re:imaginary mass (Score 5, Informative) 381

by cb123 (#41614503) Attached to: Mathematicians Extend Einstein's Special Relativity Beyond Speed of Light

If you just read the abstract to TFA you can see that the claim here is less novelty than the press release makes it sound like (the press overplays things - SHOCKER! ;-). They are really only presenting an alternate derivation without using mass of long-known results related to tachyonic physics and virtual particles and so forth.

Now, I am personally a bit dubious this is the first time the alternate derivation has been done, but I havne't read their particular approach. One would hope any reviewers assigned to the paper would have done reasonable due diligence/homework about the particulars (though sometimes that hope is in vain).

Comment: Visualizing The Scale (Score 5, Interesting) 94

by cb123 (#41364427) Attached to: Australian Study Backs Major Assumption of Cosmology
Most comments seem to be vying for most funny, but if you do happen to care about visualizing the scale, the distance to our closest full-sized galactic neighbor, the Andromeda Galaxy is 2.5 Mly. That is 1% of the homogeneity scale cited by the article. So, they are saying that things seem smooth averaged over scales merely 100 times bigger than the distance to the nearest extra-galactic clump which is sized comparably to The Milky Way. That's actually pretty smooth, in context.

Comment: Can it beat IQ if it's calibrated by IQ tests? (Score 1) 213

by cb123 (#40846729) Attached to: Goodbye, IQ Tests: Brain Imaging Predicts Intelligence Levels

The press release doesn't cover that, nor the abstract and the rest of TFA is behind a paywall.

In case the one-liner in the subject isn't verbose enough the issue is "what is being measured". One needs some kind of gold standard. "Intelligence" is a slipperly enough of a concept that in practice it tends to be "defined by" some kind of measurement scheme. This new measurement scheme has to be calibrated by some existing one -- i.e. these measurements explain intelligence as independently assessed by some other extant measurement scheme.

Unless they get a lot better at correlating than 20%-ish then either they represent a refutation of those existing schemes (which requires some other compelling argument) or they are dramatically inferior, but some new enough approach to be "publishable". The latter is probably all the research article is about. So, don't get your hopes up on "pinning down the slippery". If you are already uncomfortable with IQ tests as assessments then you probably won't accept any calibration of the new technique and thus view it even more skeptically than the existing techniques.

Comment: LHC Expense-"God" Marketing-Silliness++ (Score 1) 291

by cb123 (#40603101) Attached to: Why Were So Many "Crazy" Higgs Boson Stories Published?

Much of what is being said here is correct. Since the cancellation of the USA's SSC in the early 90s (a device that would have found the Higgs 15 years or so sooner), big science physics projects have had a hard go of things. Of course book publishers also will pounce on a catchy God particle marketing gimmick. Physicists will privately grimace even more at such over-hyping of the significance, but the difficulty of funding makes them shy away from outright rebuttal. The same people that are most "expert" in the domain have a direct interest in the domain seeming "interesting" to the ordinary folk who have to pay for it.

The Higgs mechanism only generates masses for the W and Z *gauge bosons*, not masses for quarks or leptons (see any good Wikipedia page) and certainly not "all matter" which is what a lot of the *officially* popular pieces indicate through inappropriate brevity. Without a Higgs-like particle the gauge bosons for the weak force ought to be massless like photons, but there was never, ever any problem with fermions like quarks and leptons having mass. Now, without W,Z,Higgs electroweak interactions would be very different, but it is almost totally insane to attribute everyday "mass" to the Higgs alone. Indeed, 99% of "everyday mass" comes from the binding energy of the strong force inside of nucleons, for example, not even the *rest* masses of quarks and electrons. "God particle" was never remotely appropriate. Various ideas about anti-gravity and the like are completely off track. It's important to be sure, but blown out of proportion (almost) beyond belief.

This all leads to "what bad analogies come next" in two to three decades when people want to fund (and promote) the Next Big Accelerator (NBA). The discoveries anticipated may have to do with supersymmetric partners. Could that lead to Jesus and Lucifer "offspring of God particle" or "wars in heaven" BS analogies or perhaps equally poor religion backlashes to already nutty analogies objecting to new pantheons or whatnot? Beats me. It seems likely that even allowing for global economic growth the "N.B.A." will be an even bigger fractional expense and so drive even greater craziness. Steel yourselves!

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