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Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

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### Re: the recent U.S. party conventions ...

Why settle for the least bad one when you can vote for a party that will end the government hush-up on extraterrestials, outlaw chemtrails, and make perpetuum mobile energy available for everyone? [see SOPN.nl]

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### Violation of Heisenberg's Uncertainty Principle

The 'you change the system by measuring it' is called the observer effect, and it has to do with wave function collapse and not with uncertainty.

Regarding the HUP: you can derive that without referring to measurement apparatuses, by just looking at the momentum and position operators. Let position x and momentum p each have standard deviation dx and dp, respectively, then by the Cauchy-Schwarz inequality

dx dp >= |cov(x,p)|.

The covariance of x and p is

cov(x,p) = E[(x-E[x])(p-E[p])],

where E[A] is the expected value of operator A, and as the commutator of operators x and p is [x,p]=i hbar,

dx dp >= |E[(x-E[x])(p-E[p])]| = |E[xp]-E[px]|/2 = hbar/2,

which is the Heisenberg uncertainty principle.

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### Committee Lowers Nobel Prize Award

... I'll just aim for an Ig Nobel Prize instead.

more than 2 years ago
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### Software Patents Good For Open Source?

"Any headline which ends in a question mark can be answered by the word 'no'"

more than 2 years ago
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### Kevin Bacon Meets Wikipedia With New Pathfinding Program

Taking only the obvious steps:
World of Warcraft > Role-playing game > Role-playing > Roleplay (disambiguation) > Sexual roleplay > Human sexual behaviour > Human sexuality > Virginity ("Losing one's virginity" redirects to that page.)

more than 2 years ago
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### 3 Share Nobel Prize In Medicine For Immune System Work

I would say that the invention of the sun valve (Gustaf Dalen, Nobel prize for physics in 1912) was a pure engineering achievement.

more than 2 years ago
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### Details About Raspberry Pi Foundation's \$25 PC

Re:Price of a textbook. (349 comments)

When I was in (Dutch) secondary school, textbooks used to be around €50, so that’s a little cheaper than university but still way over \$25. Secondary school students can usually rent their books from the school here instead of having to buy them themselves, so that brings the total cost down to about €10 per book for the student.

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### Details About Raspberry Pi Foundation's \$25 PC

Price of a textbook. (349 comments)

I can’t remember any of my textbooks costing around \$25. I think \$100 (€75) is the mean price.

Of course, this only validates their argument: if you are willing to spend \$100 on a textbook, spending \$25 on a pc for education is not a big hurdle.

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### Chinese Researchers Propose Asteroid Deflection Mission

> (it 'only' weighs 46 million kilograms)

No it doesnâ(TM)t. Kilograms are a unit of mass, not of weight.

more than 3 years ago
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### Bill Clinton Says 'Paint Your Roofs White'

After all, he lived in a white house for a few years.

more than 3 years ago
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### IAU Names Fifth Dwarf Planet Haumea

I wonder which they'll allow first when they run out of 'old' pantheons: planet Xena or planet Jesus. No troll intended, just wondering.

# Slashdot: News for Nerds

Man is an animal that makes bargains: no other animal does this-- no dog exchanges bones with another. -- Adam Smith

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