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,
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.)
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.
'In an interview Thursday, Palin said she meant only to say that discussion of alternative views should be allowed to arise in Alaska classrooms: "I don't think there should be a prohibition against debate if it comes up in class. It doesn't have to be part of the curriculum."
She added that, if elected, she would not push the state Board of Education to add such creation-based alternatives to the state's required curriculum.'
There is also the derivative "liberal" which has several senses connected to freedom and generosity ...and a different meaning on either side of the pond.
Slashdot Mirror
> Excuse me, I have to go delete my LinkedIn account now.
LinkedIn only gives you only the option to "close" your account. I'm pretty sure actually deleting it is impossible.
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.
... I'll just aim for an Ig Nobel Prize instead.
"Any headline which ends in a question mark can be answered by the word 'no'"
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.)
I would say that the invention of the sun valve (Gustaf Dalen, Nobel prize for physics in 1912) was a pure engineering achievement.
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.
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.
> (it 'only' weighs 46 million kilograms)
No it doesnâ(TM)t. Kilograms are a unit of mass, not of weight.
After all, he lived in a white house for a few years.
I wonder which they'll allow first when they run out of 'old' pantheons: planet Xena or planet Jesus. No troll intended, just wondering.
Yeah, I kind of expect GeenStijl.nl to have a topic on this within a day or so.
'In an interview Thursday, Palin said she meant only to say that discussion of alternative views should be allowed to arise in Alaska classrooms: "I don't think there should be a prohibition against debate if it comes up in class. It doesn't have to be part of the curriculum."
She added that, if elected, she would not push the state Board of Education to add such creation-based alternatives to the state's required curriculum.'
From the Anchorage Daily News.
If the direction is changed, the vector values are not retained. Or are you arguing that (3,4,5) and (-7,1,0), for example, have the same values?
Physics major nitpick: It doesn't keep the velocity, it keeps the speed.
And there I was thinking it came after Tobey Maguire and Reese Witherspoon used a magic remote...
You'd need an elliptical dish for that. Satellite dishes are parabolical.
'Voorwerp' would be most accurately traslated as 'Object'.
Thereby implying you do get tail the rest of the month? You must be- ah, whatever. Lucky git.
You can test it for yourself at http://www.faceresearch.org/demos/average.
Neither do we.
You can try this 'Vista'-thing. I heard nothing runs on that.
Dude, what happens in Vegas should stay in Vegas.
Actually, everything is worth what the second-highest bidder is willing to pay, plus some epsilon that's needed to outbid him.