In modern accelerators electrons routinely have energies of a few GeV, meaning that their velocity differs from c by probably less than one part in a billion (I can't be bothered to do the calculation, but the rest mass of the electron is about 0.5 MeV).
...especially since it (briefly) discusses how Philips and Varioptic built upon previous techniques. Electrowetting is nothing new, the challenging part is solving the practical problems.
Buy a cross-trainer. Some of them use magnetic resistance (eddy current brake) so one should be able to add a generator.
During a 1h training session, according to the machine I burn about 800-900 (kilo)calories, which is less than 1 kWh (not taking into account conversion losses). So I doubt that would make much of a difference for your electricity bill.
...is a phase-retrieval algorithm. If you want to project a pattern with a certain intensity distribution in a certain plane in your medium, |F(x,y)|^2, the initial beam must have a definite intensity and phase in each point of the initial plane.
The intensity is usually the Gaussian profile of a laser beam, say I(x,y) so you need to compute the initial phase p(x,y). Once you got it, you modulate the laser beam using a nifty spatial light modulator. You're done.
The algorithm is an iterative one, where you start with an arbitrary phase distribution p0(x,y), get the tentative -complex- distribution in the final plane F0(x,y) by propagation (Fourier transform); of course, its intensity |F0(x,y)|^2 will be nothing like what you wanted, namely |F(x,y)|^2. So what you do is replace its amplitude by the correct one |F(x,y)|, and keep the phase.
Now you back-transform to the initial plane, where you'll have a new phase p1(x,y), but also a new intensity I'(x,y), that you replace by the "true" one, I(x,y), while keeping the phase, p1(x,y). You keep iterating the algorithm and it converges fairly fast.
Thanks for pointing that out. I have Javascript enabled, but with all the "Advanced Javascript Options" unchecked. I was very surprised (and annoyed !) to see that the spoof page could hide my toolbar. Sure enough, at a closer look only the status bar is covered.
I guess the easiest thing would be to have these preferences "true" by default and add them in the Javascript options, should a user want to change them...
I did my PhD in France and in many physics laboratories down there Macs outnumber PCs; they are even used for driving experimental setups and for data acquisition, not just as desktop machines.
I used a PowerMac 7300 for data treatment before starting to write my dissertation (at which point I switched to PC).
Second, nowhere in the paper is there any mention of "diamond". Crystallized carbon can also be in graphite form, so it might actually be a very large pencil lead...
Did you mean "emulate" or "immolate" ? Just wondering...
Re:The real stealth inflation comes from the Fed
on
Stealth Inflation
·
· Score: 1
Or maybe the company selling the table saw knows that it can get a certain price for the item, so they just lower the quality...
As for the competition-constrained profits, this would be true for well-informed customers which, unfortunately, we aren't. People won't buy a product because it has the best quality/price ratio; they will buy it because it was advertised to death.
It's been years since I last opened a QM book, but I'll take a shot at this.
Heisenberg's principle is not related to temperature. In fact, introductory QM courses usually ignore temperature (unless there is some mention of kT, you're at 0 K). This does not mean that the particles are immobile, just that they are in the fundamental state (no excitations); the uncertainty principle still holds. Of course, if you go to finite temperature your system can jump to an excited state an the uncertainty Dp Dx will be higher than the Heisenberg limit, but that's a different story.
So, to summarize, Heisenberg says that even when you cool your system at 0 K and you prepare it in the "most condensed" state, you still can't beat Planck's constant, but it does not forbid cooling it to absolute 0 (it's the Nernst theorem which does).
As I get it, it is not (only) the outside world which needs to be aware of the famine threat, but the people themselves, who can put political pressure on the government.
Of course, in order to be able to do such a thing, they must enjoy a democratic society (which usually goes hand in hand with freedom of expression).
Although the SMS messages in China forced the government to acknowledge the problem, it is not likely that those in power can be overturned, should they fail to act to stop the epidemic, so their incentive to action is quite limited.
Here's a talk by Amartya Sen, check the paragraph on Political incentives, news media and democracy.
...there were some specific aspects that I feel are quite important and were not discussed thoroughly, thus I have a few questions to pose to the Slashdot community.
Slashdot Mirror
It's a perfectly cromulent word !
In modern accelerators electrons routinely have energies of a few GeV, meaning that their velocity differs from c by probably less than one part in a billion (I can't be bothered to do the calculation, but the rest mass of the electron is about 0.5 MeV).
Mod parent up, by the way...
Erm, leave the airplane out of it. This is Slashdot, remember ?
Not exactly, see here for the expression of K (eq. 12).
During a 1h training session, according to the machine I burn about 800-900 (kilo)calories, which is less than 1 kWh (not taking into account conversion losses). So I doubt that would make much of a difference for your electricity bill.
The title plays upon Francoise Sagan's Bonjour tristesse. In case someone was interested...
You can check the page of David Grier at New York University on this topic.
The intensity is usually the Gaussian profile of a laser beam, say I(x,y) so you need to compute the initial phase p(x,y). Once you got it, you modulate the laser beam using a nifty spatial light modulator. You're done.
The algorithm is an iterative one, where you start with an arbitrary phase distribution p0(x,y), get the tentative -complex- distribution in the final plane F0(x,y) by propagation (Fourier transform); of course, its intensity |F0(x,y)|^2 will be nothing like what you wanted, namely |F(x,y)|^2. So what you do is replace its amplitude by the correct one |F(x,y)|, and keep the phase.
Now you back-transform to the initial plane, where you'll have a new phase p1(x,y), but also a new intensity I'(x,y), that you replace by the "true" one, I(x,y), while keeping the phase, p1(x,y). You keep iterating the algorithm and it converges fairly fast.
I'm surprised nobody cited Ashcroft and Mermin's "Solid State Physics". If you want to learn about the basics, this is an excellent place to start.
I guess the easiest thing would be to have these preferences "true" by default and add them in the Javascript options, should a user want to change them...
I used a PowerMac 7300 for data treatment before starting to write my dissertation (at which point I switched to PC).
That's the challenging part...
A French company called Varioptic has developed such a lens and is close to the mass production phase.
I wonder if this has anything to do with the Russian word pis'mo (letter, writing).
That's why you should thoroughly disinfect the device with alcohol before taking the test. Erm... I mean...
Anyone else parsed the title as : "Places in Northern Europe where they have giant acid parties" ?
http://xxx.lanl.gov/abs/astro-ph/0402046
Second, nowhere in the paper is there any mention of "diamond". Crystallized carbon can also be in graphite form, so it might actually be a very large pencil lead...
Did you mean "emulate" or "immolate" ? Just wondering...
As for the competition-constrained profits, this would be true for well-informed customers which, unfortunately, we aren't. People won't buy a product because it has the best quality/price ratio; they will buy it because it was advertised to death.
Heisenberg's principle is not related to temperature. In fact, introductory QM courses usually ignore temperature (unless there is some mention of kT, you're at 0 K). This does not mean that the particles are immobile, just that they are in the fundamental state (no excitations); the uncertainty principle still holds. Of course, if you go to finite temperature your system can jump to an excited state an the uncertainty Dp Dx will be higher than the Heisenberg limit, but that's a different story.
So, to summarize, Heisenberg says that even when you cool your system at 0 K and you prepare it in the "most condensed" state, you still can't beat Planck's constant, but it does not forbid cooling it to absolute 0 (it's the Nernst theorem which does).
Of course, in order to be able to do such a thing, they must enjoy a democratic society (which usually goes hand in hand with freedom of expression).
Although the SMS messages in China forced the government to acknowledge the problem, it is not likely that those in power can be overturned, should they fail to act to stop the epidemic, so their incentive to action is quite limited.
Here's a talk by Amartya Sen, check the paragraph on Political incentives, news media and democracy.
You must be new around here...
I am relieved.
Yeah; however, the remaining 10% are not 90% as smart as him.