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Comment Re:I don't understand this ... (Score 3, Interesting) 184

Not all supermassive black holes are actively accreting. In fact, the fraction of time their accretion disks actually output massive amounts of radiation is ~10%, on patches of ~ hundred million years timescales.

A planetary system could form outside the center of the galaxy and travel close to the galactic center. You have to keep in mind that the distances between stars are enormous when compared to distances between planets. For example, our nearest star is 270 000 earth-sun distances (4 lightyears) away, while Jupiter is only 5 earth-sun distances from the Sun. So a "stripping" of planets, due to tidal forces, is extremely small, even when it comes close to the supermassive black hole in the center of the galaxy. It is true however that for the closest orbits, such as 120 earth-sun distances for S2 (S2 reaches speeds of 5000 km/s), this effect will be important. However, I suspect that while a single, quick swing-by will alter the orbits of planets (generally increasing ellipticity), that effect leads to the immediate destruction of the entire system. Normal planetary systems are also not stable systems. Changes in the orbits, interactions between planets, etc. are common; Only when stable oscillations are reached, the orbits remain the same for a few million years. So I suspect that the planets can re-arrange into a stable system (perhaps under ejection of one of the planets).

I think the changes are better if the system is a newly born star, where planetoids are still forming in a thick disk of gas and dust. Then, the partially destroyed disk can re-arrange quickly and form planets after swing-by. That would not necessarily be a problem for "spreading of life", if this process occurs e.g. via comets.

Comment Re: Cubic gigaparsec ... (Score 4, Informative) 184

Unfortunately, space is not Euclidean on giga-parsec scales. Here, when talking about 5000 Gpc, they refer to a "comoving scale". That is a scale where the expansion of the universe has been divided out, so that e.g. the same number of galaxies remain in this box. So if you would place the atoms of the number of swimming pools you computed in the volume, they would be twice as dense at the largest distances, where the Universe was half the current size. Also, the largest distance within a 5000 Gpc^3 is 3200 Gpc (space is not Euclidean).

Comment Real advantage (Score 2) 108

One cannot escape the fact that bigger apperture telescopes can record fainter
stars, and/or perfom the photometry of bright stars with more precision than a simple camera.

To detect exoplanets one needs both large samples of stars recorded as continuously as
possible over several years and high precision photometry. Besides being cheap, the advantage
of a small camera is than the field is larger. But with a larger telescope in space like Kepler one
can target regions of the sky with density of stars optimal for the CCD/camera combination, and
observe continuously for months with the same instruments, which is crucial for differential
photometry. Thousands of amateurs worldwide detecting as many new exoplantes as Kepler
would face the problem of coordinating the analysis of huge amounts of heterogeneous and
incomplete data (due to day/night and weather interruptions in differently dark and transparent skies).

The real question is wether crowdsourcing planet detection is cheaper for global economy at equal scientific return than with state sponsored research. Perhaps the most important benefit of such an
activity is educational and promotional for research in general.

   

Comment Confession - I didn't like Interstellar (Score 3, Insightful) 289

I can't be alone in not liking this film. It wasn't the science (there was obviously a lot of work done there) that bothered me, and besides which with Sci Fi you always get a 'gimme' or two (warp drive, transporters, technobabble etc) but I really didn't feel anything with the story. It didn't draw me in, it just dragged. This wasn't what I was expecting as I had been looking forward to this film since I saw the first teaser. I see so many people going on about who great this film was but I can't help but wonder what it was that I missed?

Comment Re:TIE-Fighters flying in Atmosphere?!?!?!?! (Score 1) 390

I think it was the second of the unofficial Han Solo novels during the time of the Original Trilogy that first had TIE Fighters in the atmosphere. So you're absolutely right that they're impossible, but it's "legitimate" extended canon. (Which is why I don't consider anything after the first movie "canon" at all.)

Comment Re:CGI (Score 2) 390

Plausible. Also, since it's an amateur rig, the force field may well extend well beyond the blade and not just envelop it. If that's the case, the cross guard's projectors cannot be sliced off as the force field would be protecting them as well.

Since they filmed some of the movie in Puzzle Wood and since I'm damn sure I recognize the trail, I'm going to say that's the likely location for this scene. If so, expect some seriously gnarled and twisted trees in the background. Those won't be CGI, that's really what the place looks like.

Comment Re:Lightsaber crossguard wtf (Score 1) 390

A projectile containing a Bose-Einstein Condensate.

The bullet vaporizes on the force field surrounding the plasma interior. However, this isn't instantaneous. During that time, there is a cavity in the force field. The BEC gets through this cavity and impacts the plasma. This causes the BEC to instantaneously heat up to temperatures that permit fusion. Since the nuclei are already overlapping, fusion into a mega atom takes place. The mega atom instantly disintegrates as it's violently unstable, drenching the Jedi in hard radiation.

Comment Re:http://uselessd.darknedgy.net/ (Score 1) 647

Yes, so what init system and service management are they going to use?
Is it meant just for servers? Then they could get away with sysvinit.

If this Debian derivative is meant for desktops too, then you want some type of the systemd solutions to service management, to dynamically change hostname, datetime, do hibernation, add/remove bluetooth/modem devices, multi-seat login, etc...

I think the options are: Upstart or OpenRC; the others are too obscure or untested.
Probably you would have to use the abandoned Consolekit to replace logind?

If you are unfamiliar, this is what (systemd-)logind does (and previously ConsoleKit did part of it):

.
        keeping track of users and sessions, their processes and their idle states,
        creating control groups for user processes,
        providing PolicyKit-based access for users to operations such as system shutdown or sleep,
        implementing a shutdown/sleep inhibition logic for applications,
        handling of power/sleep hardware keys,
        multi-seat management, session switch management, and device access management for users,
        automatic spawning of text logins (gettys) on virtual terminal (console) activation and user runtime directory management.

from https://access.redhat.com/docu...

Comment Re:I just don't get that. (Score 2) 117

I agree the justice system has gone haywire.

I agree the justice system has no business going haywire.

I agree the justice system has no business treating one person differently from another.

I agree that what was done was completely wrong, not just in this case but in many others.

I've said as much, repeatedly, on The Guardian's website on relevant topics. This isn't a new opinion for me.

There is a difference between having no sympathy for the guy (IMHO he deserved it) and agreeing with the justice system. I agree, and always have, with Tolkien's phrasing of it: "Deserved death? I daresay he did. I daresay there are many who live who deserve to die. I daresay there are many who've died who deserve life. Can you give them that also?" Whilst I admit that I'm "quick to judge" on occasion, I heed Tolkien's words and do not believe that "deserving" is sufficient to warrant inflicting what is "deserved". I do not believe retribution is a functional way to go about things. Trashing a hard drive with a sledgehammer might stop bugs in software affecting you, but it doesn't actually fix anything. To do that, you have to not inflict retribution but therapy, fixing the defects.

The same is true of people. Fixing the defects of character is harder, but certainly achievable in most cases. That pays attention to Tolkien/Gandalf's advice, leaves the world a richer place, and is generally a Good Thing. It's also cheaper than inflicting punishment. A lot cheaper, if the world is a lot richer for it.

He has smarts, he has savvy, with a little examination of why he chose the path he was on and some tests, it would not be hard to figure out how he could either offer the same service in essentially the same way in a protected manner, or (if he preferred) to do something different but that makes use of his skills and knowledge.

Bankrupting him has left the world poorer, because there's no way on Earth anyone will convince him to be more charitable and considerate now, and that's the only way the world would ever benefit from his skills and know-how.

To me, this is simple economics. At vast expense, the US has turned a person who was merely dysfunctional but a potential asset nonetheless to society if he could be persuaded into a dysfunctional wreck with a chip on his shoulder the size of the Empire State Building who is never going to let the world see the positive in his abilities. In short, by clocking up a huge liability, the US has achieved the dubious distinction of turning an asset into an additional liability.

I hold that there is always a solution that is both economically sound and ethically sound over the long term, over society as a whole, and that on closer examination, such solutions will always be superior to those that appear ethically sound but are economically unsound. Most of what is truly ethical is also a boost to some key aspect - to a person, society or planet - in the long term that is in excess of the cost, and thus will automatically be also economically sensible. Everything that is truly unethical may produce some short term benefit of some kind to some person, but is invariably expensive to everyone and everything in the long run. In consequence, even the ethical things with no obvious benefits will be cheaper than the great burdens created by the unethical.

I would not do well in a Star Trek universe.

Comment I've a really hard time sympathizing. (Score 2) 117

A parasite (he didn't get a fleet of flashy cars by donating disk space to anyone) gets sucked dry by a bigger, nastier parasite.

Sorry, but if you live by a dog-eat-dog creed, don't expect tears when your pet poodle is a predator's desert.

I'm sympathetic with ISOhunt, who got crippled by the UK government, as I'm willing to bet that people after illegal ISOs searched elsewhere. They're a major source of information on ISOs for F/L/OS software, though, which is entirely legal. They got a raw deal on that, because of the bad name the *AA have given torrents. Blocking the others won't do the UK any good, but that's not the point. Nor is it the point that these services index, not host. The point is that it doesn't matter whether the links point to legitimate or illegitimate content, they're tarnished not by what they index but by the mode of transport used.

Kim DotCom is another matter. He raked in an awful lot of money by doing very very little. He'd make a great bank CEO or politician, such is his level of verminicity. Had he done essentially the same, with far less profit (it's ok for him to live, just not ok for him to own half the cars in New Zealand), far less arrogance (like I said, a bank CEO or politician), and far less swagger (maybe, just maybe a touch of humility), I might pity him more. The humble earn at least some respect for being humble. It's rare enough.

If he'd presented his service as "common carrier", then that too would be worth respect. That's legal, that's all about NOT looking at what's there and NOT being shot in the process. DotCom's approach was to be a braggart. Sorry, but that kills any respect.

As judges are renown for disliking the arrogant, swaggering braggart type, that might well have cost him every court case contested. Even on the rare occasion that justice is blind, it still has a sense of smell and arrogant, swaggering braggarts stink.

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