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Comment Re:Not eliminating all "gunpowder" (Score 1) 517

This means that if you want to cause a hole larger that your launching mechanism then your launching mechanism will have to be able to withstand a larger force than you target, doesn't it?

Not really, because you have no collision on the launching end, whereas, by definition, you have a collision in the other end. A thin shockwave of hot plasma death precedes your hypersonic projectile as it is on its way to vaporize (or vaporise, if you are operating a rail gun of Her Majesty's fleet) the target, and a rather large shockwave of plasma follows, things which you will not be able to notice anyway, as there will be lots of vaporizing near the target. The impactor vaporizes part of the target, which is part of the physics involved. Consider this: small-sized meteorites produce huge craters, not meteoroid-sized holes on the Earth's crust. And typical speeds (and interestingly enough, masses) for meteoroids are of the order of rail gun projectiles.

(to cover one case where I got your question completely wrong): There is LOTS of stress going to the rail gun array, exactly because there is, as you noticed, lots of force involved, but it might not be the stress you think. The projectile needs to be accelerated to many times the speed of sound in under the length of the "barrel" (barrel-equivalent, which is the rail/rails). To accomplish that, a large magnetic field is needed, which means lots of current has to run fast through the projectile and the rails, an large current running through conductors is actually an industrial way of liquifying -and keeping liquid- chunks of metal. Furthermore, much stress may permanently deform the array after firing, rendering the gun useless until repaired.

AFAIK obvious problems are overheating and deformation.

Comment Re:Lasers are easy to stop (Score 1) 517

Which means the trajectory is parabolic

No, you are wrong: the trajectory is in fact closer to a section of an ellipse, because the Earth's pull has a gradient. Ignoring atmosphere, it can be *approximated* by a parabolic section provided the highest altitude reached is relatively low (==gradient is zero). If I was to shoot anything at long range and not miss, I would forego the parabolic approximation as it introduces errors. The parabolic approximation is only half-good for Great War Era artillery aiming. Forget about using it to aim even WW II V2s, and is certainly useless for anything ICBM-like.

Comment Re:Lasers are easy to stop (Score 1) 517

Currently the velocity of railguns is roughly equivalent to navel guns.

If 'navel' is a typo for 'naval', is that true? I have heard reports of Mach 7 speeds for railguns, can a chemical gun fire a projectile faster than that?

Eventually this speed should surpass escape velocity which means railguns will eventually be able to tag satellites

Hold your horses: you need escape velocity only if you plan tagging targets on the moon. For most satellites, a fraction of this speed (achieved by today's tech) can easily reach them.

The question in the new era is how to defend against such things so that a battle group is survivable.

A carefully placed e/m pulse could, in principle, seriously eff up the rail array, as it -by definition- is set up for optimal current flow. So I would expect more of those, as I would expect a more rigorous e/m shielding regimen.

Consider what you could do if you gave such a design a nuclear power plant, expanded the size to Nimitz proportions, and replaced the planes entirely with more compact drones.

That might be useful for media purposes and intimidation, but for actual mil applications you should consider the huge energy footprint of such a contraption: a 24/7 surveillance of the ballpark area of where it would be most probable to surface would make it very tricky to deploy: enemy would see a large glow on all bands, easy to target with their own hypersonic projectiles. On the other hand, if there are no souls aboard (though unlikely for a sub) you could not care less.

Comment Re:Wrong strategy (Score 1) 66

Some time ago I took a long, hard look on "Skype alternatives". Let me share my finds with all of you:

Skype is Shit. Let me repeat that: Skype is Shit, and this Shit that Skype is mostly became shit after Microsoft messed with it. Allow me to elaborate:

- Call quality auto-degrades, when Skype 'decides' you are not to be prioritized. No other option given to the user to prioritize or adjust it in any way; useful settings to manage call parameters are virtually non-existent;

- Land line connectivity is poor, with low success rates (try it for yourselves: try calling from your regular phone the line you just failed to get a connection, and see how quick and crisp the result is);

- Privacy is a joke, even the links one pastes in Skype's chat interface trigger Microsoft spider bots that show up to check on the link shared. Again, try this for yourself and see what happens. I would not be surprised if the infamous Facebook policy is applied (the one that saves not just what you post, but what you type in the textboxes, even if you hit Backspace);

- The super useful desktop sharing function was made a PREMIUM service. That was the straw that broke the camel's back for me.

- Over the years, and version after version, the ads have become audaciously overwhelming. The current image of Skype's window on your desktop crammed with its glam and glitter ads is plain silly. Grandma (for whom most of us maintain Skype) is having a hard time figuring out where to click to bring up which window that may or may not have the big green button she is looking for.

- Dodgy background processes and connections doing dodgy things. Again, be my guest and check for yourselves. Try your everyday sysadmin tools and see what you get.

>> Skype works on any Windows/MacOS computer, virtually any iOS

I will challenge that: depends what you mean by "works". For example, it does not work on my Mac. And by "does not work" I mean that a not-so-old version will fail to connect. "Have you tried the new version?", you may ask. No thanks, I decided against it after reading the EULA. Again, try it; it was an insightful read for me. Clearly there was lots of effort put into writing it, so why not do them a favour and read it? Note that the juice here is not my predicament and my ideas of what 'this software works' means, but Microsoft's choice to piss on their users and cripple earlier versions in order to extort upgrades.

>> A better comparison would be Google Hangouts

I understand this, but really, it boils down to whether you believe that you are getting a good deal or not from Google (or anyone) for your person. If you go this way, you would be an utter fool if you expect any kind of privacy on your otherwise designated 'private' communications. Google will keep recordings of your sessions at least until a biblical proportion flood or a meteor impact event physically destroys its data centres. Until then, Google (or whoever is in their shoes at the time) will ever-analyze and dissect your data, with current and ever-developing algorithms and resources: that's what Google DOES in its core.

A very simple to set up a convenient videoconf scheme is to use something o p e n s o u r c e (say Jitsi), and use it to handle an o p e n (say XMPP) protocol. Set one up for grandma as well, show her where the green button is, and videochat with her with strong end-to-end encryption, keeping those magick cookie formulae of hers only between her and you. You taught grandma Skype, you can teach grandma this one as well. Grandma knows.

Make sure you at least give your friends and associates a chance to break out of this Skype/Hangout trap that we tech-informed people have totally set up for ourselves, stop using the ".. but everybody uses Skype .. " and ".. but my contacts .. " excuses, and deliver the message that the architects of this centralized, interceptable, controllable and overseeable form of arranging global communications can shove it arbitrarily deep into their own faschist arses, by refusing to use it and informing as many people as you can about the obvious and ridiculously easy to obtain alternatives.

If you go the extra mile and pay the excruciating amount of $10 to some third telephony party, you can also integrate them via SIP and have the ability to place numerous calls to landlines and cells. Again, numerous small companies, numerous plans for diverse budgets.

Overall, why ever prefer a 'blackbox' type software, for something you can do with opensource? Because the blackbox "just works", "works better", "has guarantees" and the like, that's why: only that this is not the case with Skype and Google, since simple opensource buggy XMPP-handling programs at their first buggy steps already perform better than the establishment.

Comment Re:That Would Assume (Score 1) 95

Aliens don't know better than to shit where they eat. We could be the only species in the galaxy that's so stupid.

But can you imagine if not? Imagine: an alien civ, similar to this one, but at an earlier stage of development. Ripe to be exploited. Would you then, for one, welcome yourself as their alien overlord?

Comment Just to get through the misleading stuff: (Score 5, Informative) 94

After the election of a new European Parliament in May this year, Jean-Claude Juncker has been nominated to become the new President of the European Commission

Basically, all of EU 's administration that matters is chosen by the running governments of the member-states: all administration is merely an assembly of the guys already in charge. The European Parliament has had very little to say on administrative issues, and this is the first term that the European Parliament's members will presumably have the power to block EU directives (something that remains to be seen how it works out): and this is the only part that they will have in the law-making process --the European Parliament DOES NOT have the power of legislative initiative.

FYI, so you do not get carried away by flashy designations and think that this is an actual parliamentary representative democracy akin to national parliaments: it is not.

Comment Known issue, Has workarounds: (Score 1) 102

M dwarfs are very interesting because they are the most common kind of star, and they have a very high potential of hosting planets able to support DNA-based life as we know it. M dwarfs are also expected to exhibit strong magnetic activity (star spots are magnetic features) as they are highly convective. Star spots appear darker in the optical wavelength, and can easily be mistaken for planets.

There is active research going on that tries to filter out this interference caused by the magnetic effects, and as most public-funded science is unfortunately (and audaciously) paywalled

Submission + - China's Tianhe-2 Tops Supercomputer Chart Again (

arisvega writes: China has the world's most powerful supercomputer for the third time in a row as the country once again ups its presence in the global top 500.

Tianhe-2 was top of the twice-yearly list that keeps tabs on supercomputer development and growth.

Since the last list, China had 20% more supercomputers in the top 500, while US representation went down 15%.

However, the US still dominates the chart with 233 computers making the latest tally.

China had 76, up from 63 in the last count. This is almost as many as the UK (30), France (27) and Germany (23) combined.

The full list is to be published Monday (today) at a conference in Leipzig, Germany.

Comment YouTube is not all there is (Score 1) 197

This will certainly backfire not very long from now: basic reasons why youtube is big is because a) was early, and b) is a high-bandwidth streaming service that you can dump (and find) more-or-less what you want. Take this away, or make it complicated, and soon the tech-savvies or the home/small business people will pull out; and the middle class iPad living room seniors surfers will --sooner or later-- follow.

Comment I agree, plus proposal: (Score 1) 77

The music industry has a long and sordid history of ripping off the artists...


The music industry got cold sweat from the diversity of available media (vinyl, magnetic tapes, optical disks, whatever) and the easyness of internet sharing and binded the artists with all-encompassing contracts, taking the music out of their hands: you are not allowed to perform your own songs in public without your label sanctioning it (and making millions from your fans by selling them beer) first because, technically, they are not your songs any more.

In return, the label sends its armies of lawyers (along with corrupt government elements) to Hell and beyond to track, terrorize and imprison teenagers who had the audacity to publicly share even a small exrept of the (formerly yours) work, and grand you your 0.00000000001% cut from the process.

I only know the book publishing "established" rules a little bit, and -unexpectedly- they are not too much in favor for the writer either.

A good initiative, especially in the music industry, is to have different classifications: streaming is not vinyl is not concert, and those things need to be handled seperately. Artists need to stop signing those all-encompassing deals and a very good start would be e.g. to use a label to produce an LP, then go to a different label and let them handle your content via streaming on the internet: do NOT give up all rights for your art, because that is what you live from. The labels will resist of course but if enough artists do it, then it is done.

Comment Re:Vive le Galt! (Score 1) 695

[..] an outlandish system of universal volunteering which barely even works in theory let alone practice?

I understand how you may be convinced that money is the only viable option, and other systems that you are conditioned to believe that 'barely even work in theory' seem to you like naive romantic notions. A world without money? How is that even possible, right? THAT is how bad the situation is.

The request was that you be less ridiculous, not as utterly absurdly ridiculous as possible.

Instead of acting like an opinionated smartass, may I suggest that you direct your vigor towards actually investigating a few of those 'outlandish' systems and their underlying principles: ubuntu may be a very good place to start.

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