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Comment: Re:This guy... (Score 1) 143 143

Yes, but a Kugelblitz requires two or more massless particles to interact to form a black hole (because while a photon is massless and can never form a black hole, a system of photons is generally not and certainly could given the right conditions). And a heat-formed kugelblitz would generally not be stable: black holes radiate energy same as any black body (in fact, black holes are basically perfect black bodies), and dissipate at a rate inversely proportional to their mass, which means at around the black hole forming temperature black holes would pop in and out of existence as they formed and quickly dissipate. They'd just become part of the thermal equilibrium system. Granted, he is right that at extremely high temperatures black hole formation would start to become stable, which would probably prevent temperatures above a certain point. But, as I say, that is way beyond our current physics.

Comment: Re:This guy... (Score 3, Informative) 143 143

This guy has anawful lot of confidence in how the universe works, I'll give him that much. I am only a lowly being compared to him, but isn't this all speculation? I'm pretty sure this is not a science with any kind of proof or even basic consistent knowledge, but don't let me get in the way.

You are correct, it's mostly a bunch of pop-sci woo-woo. For example, a massless particle no matter how energetic cannot on it's own convert into a black hole as he claims, because no matter how much energy it has you can always Lorentz boost into a frame where it has arbitrarily small amounts of energy. Likewise the photons in your room have arbitrarily large amounts of energy, depending on the reference frame you choose. But they have no mass, and a system requires a certain amount of mass to convert into a black hole (and the mass of system is invariant, i.e. it's the same in every reference frame).

The "the Universe would be destroyed" bit is also completely and purely theoretical at this point: we have no real proof for inflation at all. Our physics just doesn't really extend to those energy scales yet.

Comment: Re:$68 Billion for high speed trains (Score 4, Informative) 599 599


Oh yeah, that looks like a nice unbiased source. For example, it omits to mention that 2/3rds of the water that goes into animal feed is "green water", i.e. rain and other renewable sources. In other words, animal-based foods require large amounts of water, but it's mostly renewable water. In order to say that getting rid of lifestock would actually help the problem, you'd need to look at how much water would be required for foods to replace meat and dairy entirely, and where that water would need to come from (it doesn't help the problem if you replace lifestock with plants if those plants end up requiring more water from aquifers than the lifestock does).

BTW here's the full report (PDF warning) on water usage in California if anyone is interested in more numbers.

Comment: Re:uh, so? (Score 4, Insightful) 127 127

Why? Manufacturing goes overseas because it's cheaper, but when you automate the process or require skilled labor it's not really any cheaper to offshore it. In fact, according to Wikipedia the US has more chip fabs than any other country. Significantly so. In fact in general the US is third in the world (behind China and the EU) in total manufacturing output. It just doesn't have very many manufacturing jobs anymore, because most of the plants went hi-tech.

Comment: Re:Even More Thrust (Score 3, Interesting) 265 265

Existing ion thrusters already use ionized Xenon for propulsion, so it's definitely a possibility (charge the graphene using this technique, ionize the Xenon and use that to neutralize the graphene, use the Xenon as ion thruster fuel). However, electrons are very nearly massless, so unless they're somehow exciting them with massive amounts of energy, the propulsion from the electrons is unlikely to be significant.

Comment: Re:And probably infinite (Score 1) 235 235

Inflation doesn't require tuning, all it requires is that the amount of inflation is large enough to explain the observed flatness (as well as CMB thermal equilibrium and lack of magnetic monopoles, which again just means it has to be greater than a given amount). The fact it doesn't require tuning (as far as we know) is a large part of the appeal of inflation as a theory in the first place.

Comment: Re:And probably infinite (Score 1) 235 235

The real mystery though is how the universe could be very nearly flat (without being exactly flat). Such "fine tuning" is clear evidence we're missing something quite fundamental. But then, dark energy already tells us that.

Inflation already answers that question (assuming it turns out to be true). Even a very non-flat universe becomes apparently flat if you massively inflate it (in much the same way as the Earth appears flat to people on it because it's incredibly large compared to our perception of it).

Comment: Re:Windows !!! (Score 4, Insightful) 93 93

Stuxnet used multiple zero-day flaws across several different kinds of hardware (not all of which were even PCs). Once you get into that advanced an attack, the underlying OS becomes much less important: all software has flaws in it, and if you know where the flaws are, you can exploit them. And those flaws are there (remember Shellshock, anyone?), except in the most basic purpose-specific programming (and even then, there are often flaws). Using Windows opens you up to more generic attacks, especially if you deliberately lower (or don't use) Window's defenses for ease of use (much as using root for everything in Linux does), but against targeted well-funded attacks you should assume they're more or less equally vulnerable.

Comment: Re:Hasn't this been proven to be junk science? (Score 2) 313 313

Insects can be, but that's because freezing during the winter and thawing during the summer is part of many insects survival system. Some larger animals can do this as well, IIRC, but they have specially developed systems for it that basically replace most of the water in their bodies with an anti-freeze solution. In theory it's possible to do something similar with humans, but we're nowhere near the technology to do so. Modern cryogenics might be good for preserving human tissue for future analysis (to observe genetic drift and the like), but that's about it.

Comment: Re:Landed OK but tipped over (Score 1) 117 117

That's almost certainly one thing SpaceX was hoping to help determine with this landing. If it'd landed properly, they'd take it apart to see where there was wear and tear, and what needed replacing/fixing (or redesigning) as a result. That'll have to have to wait for the next launch, now, though they may be able to still recover some of the rocket for analysis (it fell over, but I'm assuming it's still physically on the barge).

Comment: Re:Hell No Hillary (Score 1) 676 676

What? Seriously? Did you follow any political news over the past few months? Cause I mostly avoid politics entirely and I bloody heard about it. She completely admitted it here. Hell, she didn't even have an official government address, and apparently never did. And yes, keeping all your email on a private server grossly violates government record laws. The Bush administration apparently did something similar. But of course they did it only "for convenience". The fact that it left them completely in control of their email records never even crossed their mind! /s

Comment: Re:These days... (Score 1) 892 892

Everyone's focusing on the first part of that sentence, and not the 2nd... Take two people who negotiate equally strongly; the one with the penis is called confident and achieving, the one with the vagina is pushy and catty. So too late, some people (the one's with the vaginas) are already being punished for being good at something.

Then the problem is that attitude, not the negotiation. Removing the negotiation just allows the attitude to continue unnoticed. In other words, it treats the symptoms, not the disease. This may (or may not) be advantageous for women in the short term, but it'll hurt them in the long run: both the individuals, because now they're working for a (at least somewhat) sexist boss, and how much do you think they're gonna get when it comes time for a raise? And for women in general, as sexism persists in the manager culture.

Her proposal is sexist and will probably be bad for both sexes. Good for the short-term bottom line for Reddit, though, since salaries will be lower! Which I suspect may be her actual goal (gotta boost those profits).

Comment: Re:It works at least as well... (Score 5, Insightful) 124 124

Killing MRSA is easy. Trivial, even. You can do it with steam, alcohol, or dozens of other disinfecting agents. The key is to be able to kill it inside an infected individual, without also killing the host (or damaging a significant amount of the host's tissues). That's why we use antibiotics in the first place. While it wasn't entirely clear from skimming TFA, it very much sounds like this is (currently, at least) only a topical treatment (i.e. it's applied to the skin). It might be superior to other modern topical treatments in some cases, but I personally doubt it.

Comment: Re:Doesn't smoke or drink or have tattoos (Score 5, Insightful) 569 569

Dear mother, smoking, drinking and having tattoos are not good traits, but they are not necessary for someone to be a nasty criminal.

Curious - what is necessarily wrong with those traits? Obviously, from the story, one can be quite devastatingly evil (causing an incident resulting in innocents at gunpoint) without them.

Smoking gives you cancer, drinking ruins your liver and can result in uncontrolled behavior (brawls, DUIs, etc), and tattoos basically ruin your chance at a lot of jobs. They're also all correlated somewhat with anti-social behavior (of various kinds) in general, which I think was the point the mother was relying on. "Because he lacks traits correlated with bad behavior, he must not have engaged in bad behavior." Obviously, this is faulty, but mothers often aren't rational when it comes to defending their kids.

Comment: Re: 8 bit per photon on my desktop: spectrum analy (Score 1) 91 91

Quantum crypto. Isn't of much use to the industry.... compared to say....... getting 100 Terabits of second worth of data down a single fiber optic cable.

Bulk data transmission and quantum crypto have somewhat different target industries (though anyone using quantum cryptography is probably using it to secure high-speed fiber lines). Quantum crypto is used (as in used, right now, today) for quantum key distribution in environments that need/want extremely high security so they can communicate extremely securely over regular (but fast) channels.

Algebraic symbols are used when you do not know what you are talking about. -- Philippe Schnoebelen