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Comment Re:Dr. Manhattan (Score 2) 35

Mouons that come into being from fission decay reactions arent quite as energetic-- but still useful for imaging purposes.

There are (almost) no muons produced by fission. Fission events produce energies of around 200 MeV. Muons have a mass of just over 100 MeV. The phase space available for muon production is essentially nil because so much energy is almost always carried away by the fission products. Basically, to make a muon you have to have everything else stand still. The production rate isn't quite zero, but is close enough to it to not matter.

The technology they are using in this case is to look at cosmic ray muons passing through the reactor core. Similar technology was used to look for undiscovered chambers in Egyptian pyramids in the 80's, if memory serves: cosmic ray muons have ridiculous amounts of energy (they are the bane of neutrino physicists because no matter how deep the lab the muon signal is still appreciable, even under a kilometer or rock. SNO, which is one of the deepest labs in the world, is 2 km down and muons are still detectable, although only at rates of a few per day if memory serves.

Comment Re:Not worth it. (Score 1) 49

Electric cars wouldn't use half the country's electricity, passenger vehicles' share of total energy consumption is much smaller than that. But I don't disagree with you that it's bad to waste power. Still, for a potential EV consumer whose turned off from EVs because they're lazy, if the choice is between "waste 20% more electricity" and "keep driving a gasoline car", the wireless EV is still the much better option.

Comment Re:Just stop it with the 'zero emissons' claims (Score 3, Informative) 49

You act like there's no research papers on this subject. There have been tons, and the conclusions in each case are the same:

1) CO2 emissions would decline even on the US's current grid (which is, I should add, getting cleaner every year, while the amount of emissions associated with oil production keep rising)

2) On a generation basis, every region in the US has enough space capacity for a full switchover of the passenger fleet today, without any new plant construction, except the Pacific Northwest. Most charging is done at night when most power plants lie idle, but the Pacific Northwest is an exception because their heavy use of hydro means time of use isn't important, only net consumption.

3) The only thing that there's not enough of at present is simply local distribution capacity, to peoples' homes.

Of course, that's for a complete, instantaneous switchover, which is of course an impossiblity. Your average car is driven for about two decades before it goes to scrap, only a small fraction rotate out of service every year. And that's assuming that everyone bought EVs as replacement, which if course is an impossiblity because even if everyone was suddenly sold on the concept of EVs it'd take a decade or more to ramp up production to that level. And of course everyone is not suddenly sold on the concept of EVs. You're looking at maybe a 30-40 year transition time period here. If power companies can't keep up with a trend that's stretched out over the scale of several decades, they deserve to fail.

Comment Re:"Programmers" shouldn't write critical software (Score 1) 157

How many people are going to be killed by C++ in the next decade?

None. However, a few will be killed by C++ programmers. I say this as someone who has written code to guide surgeons, but my mantra was: "The surgeon is in control", and I have in fact seen surgeons over-ride the guidance information the software gives them.

Driverless cars are actually less likely than humans to screw up, I think, but it'll take another decade to prove that. Software engineering is still a nascent field, but in another generation or three it will be at a point where we can be somewhat confident in most critical code. Unfortunately, it will still be dependent on hacked-together operating systems and heuristically designed hardware...

Comment Re:Could have fooled me (Score 4, Interesting) 221

Does Canada have lots of relatively successful* politicians with whackadoodle opinions on climate change, Earth's age, and female reproductive biology?

We are having a bit of a moment with some wack-jobs in the "Conservative" Party of Canada at the moment, which is actually a radical populist party that is opposed to everything conservatism in this country has ever stood for (fiscal probity, institutional stability, Westminsterian democracy...)

A few of the loonier tunes, like Justice Minister Peter McKay, seem to believe that women have no agency (or at least that's what one infers from his attempts to push a "Swedish model" prostitution law through the system) and I believe former party leader [*] Stockwell Day is on record for a Young Earth.

This has more to do with the wonderful (and I do mean that seriously) randomness of our electoral system, which is capable of electing a majority government with 35% of the vote, as well as the institutional disarray of the Liberal Party in the past decade. We're reasonably likely to throw the bastards out next year, although the Liberals have more than a few loonies of their own.

[*] The history of the CPC is complex, but Day was the leader of one of it's fore-runners about ten years ago.

Comment Re:Biased (Score 5, Informative) 221

The clincher for me - which indisputably shows the authors' bias - is that Canada ranks #1 in people protesting GMOs and nuclear power, and the authors consider this a good sign that their population is scientifically literate!

The report says nothing of the kind. Did you read it? GMOs and nuclear power are mentioned as divisive issues, but there is no data on the ranking of people against them.

The Globe and Mail article says, "Canadians also expressed the lowest level of reservation about science and its impacts. Compared with the U.S., Europe and Japan, far fewer Canadians said that they thought science is making our way of life change too fast."

Sounds about right.

Canadians are generally very aware that our lives would be miserable if it weren't for science and technology keeping us safe and warm and fed. We have our tree-hugging reactionaries, of course, but they have far less influence than you might think despite the vast amounts of noise (and I do mean "noise" in the information theoretic sense) they generate.

Comment Re: A fool and their money (Score 4, Insightful) 266

I know this runs against everything /. but I have seen it work a couple of times.

Why do you think that an unconfirmed anecdote being presented fallaciously as an argument is against everything /.?

It would actually be astonishing if no one had "seen it work a couple of times", for several reasons. One, if there were a 100% failure rate dousing would have been abandoned years ago. Even pre-scientific peoples mostly abandoned things that were never, ever correlated with their nominal goals.

Second, given humans are known to be prone to confirmation bias, we can predict that almost everyone who has ever seen a dowser identify one of the many, many places where water can be found will come away believing "dowsing works".

So a large number of scientifically illiterate people saying, "Hey I saw it work a few times that proves it's true so I believe it!" is exactly what science would predict if dowsing doesn't work.

If dowsing did work science would predict a bunch of peer-reviewed studies systematically detailing how accurate it is and investigating the factors that influence it's accuracy.

We see the former, not the latter.

Posts like yours actually constitute evidence that dowsing does not work.

Comment Re:The show is filled with mostly nonsense (Score 1) 364

One of the most interesting episodes I saw was when they were testing something Jamie said in an earlier episode: That if two trucks collide at 55 MPH, it's like one truck hitting a brick wall at 110 MPH. At first I thought "duh, everyone knows that's true" and I continued to think that as they set up experiments, right until they were about to let two clay blocks swing into each other at which point a light bulb lit up above my head, and so I quickly hit the pause button and thought about what was going to happen, and realized that since each block of clay was simply going to stop the movement of the other, each was going to end up in the same condition it would have been in had it simply slammed into the "immovable object" instead, and thus two vehicles each going 55 MPH in a head-on collision is exactly like just one vehicle hitting a brick wall in a 55 MPH collision. ...and I suppose it's solvable with math too, given e = m * v, and so if two objects slowing down one unit of speed yields two units of energy, or one unit per object, then one object slowing down two units of speed yields four units of energy, which is four times as much, even though the difference in speeds is identical in each case. ...but I was certainly misinformed about how it worked, and I don't think I was the only one, so it was totally worth doing an episode on, indeed it was one of my favorites since I actually learned something.

First, E = 1/2 m*v^2, not m*v, although your later statement seems to acknowledge that.

Second: you are correct that the two situations are not the same, because the energy in the center-of-motion (zero momentum) frame of the two vehicles is what matters (you can think about this as the kinetic energy that is available to deform the vehicles in the crash, leaving them with a lot of bent metal and no momentum after the crash.)

With two trucks moving toward each other at equal and opposite velocities, the zero momentum frame is the just the ground, where the total energy is m*v^2 (twice the energy of each individual vehicle).

In the case of hitting a wall, the wall has effectively infinite mass, so the zero momentum frame is moving with an infinitesimal velocity toward the truck, and the total energy is 2*m*v^2 (where "v" is still 55 MPH and the multiplier come from squaring the factor of two in front of it to get the full 110 MPH of the single truck).

So in the case of hitting a brick wall, there is twice the energy available. This is quite different, conceptually, from the explanation you've given, which is wrong. In the case of a vehicle hitting a brick wall at v = 55 MPH the energy is just 1/2 m*v^2, not m*v^2 as in the case of two colliding vehicles, or 2*m*v^2 as in the case of a vehicle at 2v hitting the wall.

The history of science teaches us that what is intuitive to any particular person is unrelated to the best way of understanding the world, and your reasoning is a nice example of this: it got you part way toward a correct conclusion, but fell short of the full understanding that the general principles of Newtonian physics give us.

Comment Re:Real Reason for funding this (Score 1) 126

Or both. Any new understanding of the world will be used in as many ways as people can think of using it. I wrote a novel that speculates on precisely the topic of what might happen with exactly this kind of technology, and part of the fun was thinking about how different groups might use it for good or ill: http://www.amazon.com/Darwins-...

Comment Re:What lessons are the video games teaching? (Score 3) 1262

Oh gosh, look the screenshots of her evidence tweets came twelve seconds after the tweets themselves, from someone who was not logged in and hadn't done a search.

Almost as if...

...she got a notification of the tweets aimed at her, viewed them without logging in and screen-capped it.

The level of paranoid thinking required to believe that it is more likely that a public figure like Sarkeesian would violate the law by faking threats of this nature than that an obviously hate-filled, fragile and easily offended group of nutjobs has a few members who are so over-the-top that they would actually threaten her speaks to a deeply deranged sense of the world.

Look at the discussion here on /. There are people who are absolutely incensed at her relatively mild and well-documented criticisms of some common features of video games. I personally find her theoretical approach a tad doctrinaire, but for depth and quality it easily exceeds the bar required to get a PhD from a decent school (I have a PhD--in physics--from a decent school, and have friends in a number of fields, so I've seen the standards of humanities departments up-close-and-personal.)

So what is more likely: that a large, irate, irrational, angry mob contains a few nutjobs who would go so far as uttering actual death threats, or that a well-known, widely respected, widely reviled public figure would go to such lengths to fake threats, putting her in a position of risk of discovery and criminal charges when it is inevitably found out?

Anyone who picks the second option as more likely is living in a paranoid fantasy of the kind that might lead them to, well, make death threats against a public figure they disagree with.

Comment Re:Cut the Russians Off (Score 2) 848

That's a rather one-sided view of what happened. Yes, the Soviet Union did invade Afghanistan as part of pushing its global ideology, much like the USA invaded Vietnam. But the stone age state of Afghanistan at the time of the US invasion in 2001 was a direct result of America supporting religious fanatics in a proxy war, the mujahideen, who after the war ended and the Soviet's were defeated went on to become the Taliban. That's why bin Laden is so famously a former ally of the US.

The USA is not only building an empire but doing so in plain sight of everyone. To quote Putin directly:

Our partners, especially in the United Sates, always clearly formulate their own geopolitical and state interests and follow them with persistence. Then, using the principle “You’re either with us or against us” they draw the whole world in. And those who do not join in get ‘beaten’ until they do.

This principle is most clearly visible in two acts. One is that the sanctions on Iran are built as a "you're with us or against us" model. Any country that is seen by America to be "undermining" the sanctions i.e. not joining in is itself sanctioned. And the second act is again sanctions based: every financial institution in the world is being taken over by Washington via a system of recursive ("viral" if you like) sanctions that require banks to obey the USA even if that would contradict local laws. The goal is to collect tax from American's abroad. It's called FATCA and it's resulted in many, many nations having to repeal their own privacy laws, in order to allow banks to become agents of the US Government. They were given no choice in the matter.

So the USA has found ways of forcing people in countries all over the world to: (a) engage in economic warfare against America's enemies and (b) pay taxes directly to America, all regardless of what the local government wants or how the local people vote.

Being able to conscript people to their fights and force payment of taxes is the very foundation of empire itself.

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