Like the article said, the issue isn't processor speed, it's algorithm time as a function of input size, i.e. logN. Factoring integers takes an exponential amount of time on classical computers. The best known classical algorithm (called GNFS) is O(exp((logN)^{1/3}(loglogN)^{2/3})), whereas Shor's algorithm can factor N in O((logN)^3) time. But, Shor takes roughly 2^N qubits to factor N. So, if we're talking about factoring a 200 digit RSA number, that's a whole crapload of qubits to control. Many orders of magnitude more than we can control now. In short, you're absolutely right about quantum computers being completely impractical until there are some huge breakthroughs in engineering and physics. This is why I love being a math major. We don't have to worry about silly things like actually building a quantum computer. We just sit around and daydream about how a quantum computer would work, then when we've got it all figured out, we blame the physicists and engineers for not building one.
Not exactly. Quantum computers can simulate classical computers with no problems. That's one of the tenets of quantum computation. I would love to see a 747 parallel park in Manhattan.
Also, the fact that quantum computers can factor large integers efficiently necessarily implies that they can do other NP-complete problems efficiently, such as the traveling salesman problem. If we can ever get more than seven qubits to behave, we'll be amazed by the things quantum computers can do. But, alas, scientists have only implemented Shor's Algorithm for factoring integers on one number. 15. And hot damn, they got the factors right, 3 and 5.
Yes, IAWAUGTOQC (I am writing an undergrad thesis on quantum computation).
I remember when I was in high school, we made cars out of blocks of balsa wood. It was a little like the Boy Scouts' Pinewood Derby, except more high tech. We'd make the cars as light as possible, paint them with dozens of coats of lacquer, put skinny wheels lubricated with graphite on them, and throw a CO2 cylinder in the back. One hit with a hammer and nail, and BAM! I think my car went over 70 mph. They had two eyelets on the bottom so they'd stay on the track made out of a single strand of fishing line. This appeals to all kinds of people who love to trick out cars, work with wood, or nerdy engineer types who come up with the best aerodynamic shape.
2^24036583-1, which contains over 7.2 million digits.
The linked.txt file is 7.1 MB, so it probably will take a while. The Google cache doesn't do the number justice. In fact, the cached number is divisible by 2...
unfortunately.. China is almost 40 years behind the U.S. so it may be a while
Not exactly... As people have been mentioning with Space Ship One and the private space industry in particular, there is a lot of borrowed technology and knowledge from previous missions. A lot of the legwork has already been done. But you are absolutely correct in saying that competition is good. Ain't no good capitalist gonna let no pinko commie space rocket beat us to space again!!! (Holy crap that triple negative actually came out logically correct!!) I think it'll be interesting to see who gets to Mars first, China or non-government private enterprise. We're in for a good show no matter what.
Dammit slashdot!! You killed everyone's favorite election predictor site! Oh well, http://www.slate.com/ has a good map, similar to http://www.electoral-vote.com/. Let's see if MSN's servers are any better.
Nope, I'm in Oregon and we need all the Kerry votes we can get. I did, however, vote for a Socialist and a Libertarian for a couple state offices that were sure things for the incumbent Democrat. Voting your hopes is an art, and unless you're in CA, TX, or MA (along with some other out-of-play states), vote Bush the hell out. Anyone who lives in FL, OH, or MI especially, don't live in an idealistic dream land. A vote for a 3rd (or 4th or 5th) party candidate there IS a vote for Bush. Don't screw this up like swing-state Nader voters did in 2000.
Go to http://www.electoral-vote.com/. If yr state is not a deep red or blue, VOTE KERRY. If you live in a state marked "Strong Bush" or "Strong Kerry" go ahead and vote for the candidate that you WANT in office, and not necessarily the one that has any shot in actually getting elected.
I'm from PDX as well. E-mail the monument scientist Peter Frenzen pfrenzen[AT]fs[DOT}fed{DoT}us and he'll be able to help you out with where to send your donations.
Now I can take pictures of Mt. St. Helens' glowing rocks! Before, my camera lens kept melting. With this new ceramic heat-resistant lens, my time on the volcano is only limited by the durability of my asbestos suit!
No, actually, it's quite safe. Coldwater Ridge Visitor's Center is located literally right on the edge of the blast zone for the big eruption. If I were standing there on a certain morning in 1980, yeah, I'd be toast, but this one is not going to be nearly as big (if it actually KABOOMs, which it may very well not). The Forest Service isn't stupid, that's why they closed Johnston Ridge Observatory, which is much closer to the crater. See this map http://www.fs.fed.us/gpnf/04mshnvm/global/images2/ mshrec.jpg of the area. The beige part is the blast zone (basically pea gravel, ash, and shrubbery), green is trees courtesy of Weyerhauser Lumber. Besides, there are about 15 satellite trucks parked in a lookout point nearby, each with a few hundred thousand bucks worth of very nice broadcasting equipment. If I trust the news guys, (which I do 110%!!!!!!!! ha, no...) it's safe. Either way, don't be such a wuss, get the hell up there and see it, it's beautiful.
...and plan to go again next week. I'm from Portland, so it's only about a 1.5 hr drive from here. Last time (tues oct 5) , we left as soon as we heard there was a steam/ash eruption but got there about an hour after the plume had dissapated. Got some cool stories from people who had been camping out there for days. The Forest Service is doing a great job of accomadating gawkers like myself. On the way into the Coldwater Ridge visitors center parking lot, we were stopped and instructed to go inside should an ash fall occur. Too bad none fell.
Also, I climbed MSH the day before they shut down the mountain. There were a couple dozen earthquakes while I was on it, including one right when we were at the top. Of course I didn't know it at the time, only when I got home and checked the website.
If you're close by, I highly recommend going, even if it doesn't blow while you're there. Supposedly (!!!) it's safe, plus you can see the lava dome and its new little buddy from the visitors center.
...less than a week ago, on Saturday Sept. 25th. There were a couple dozen quakes while I was on the mountain, but I didn't feel any of them as they were less than magnitude 2.5. Before we climbed, we were told not to look over the crater rim, as a steam explosion could hurl rocks at us. How counterproductive! Naturally, everyone looked anyway, because if there was an explosion, we wanted to see it. I climbed the mountain last year, and the weather was terrible. This time, it was perfectly clear, and I could actually see into the crater. (BIGGEST HOLE EVER) There were no signs of any gases escaping, although we could occasionally smell sulfur. It looked perfectly calm. Almost too calm...
I live in Portland, and the winds say an ash cloud would head right towards us. I've got dust masks just in case...
Slashdot Mirror
Like the article said, the issue isn't processor speed, it's algorithm time as a function of input size, i.e. logN. Factoring integers takes an exponential amount of time on classical computers. The best known classical algorithm (called GNFS) is O(exp((logN)^{1/3}(loglogN)^{2/3})), whereas Shor's algorithm can factor N in O((logN)^3) time. But, Shor takes roughly 2^N qubits to factor N. So, if we're talking about factoring a 200 digit RSA number, that's a whole crapload of qubits to control. Many orders of magnitude more than we can control now. In short, you're absolutely right about quantum computers being completely impractical until there are some huge breakthroughs in engineering and physics. This is why I love being a math major. We don't have to worry about silly things like actually building a quantum computer. We just sit around and daydream about how a quantum computer would work, then when we've got it all figured out, we blame the physicists and engineers for not building one.
Not exactly. Quantum computers can simulate classical computers with no problems. That's one of the tenets of quantum computation. I would love to see a 747 parallel park in Manhattan. Also, the fact that quantum computers can factor large integers efficiently necessarily implies that they can do other NP-complete problems efficiently, such as the traveling salesman problem. If we can ever get more than seven qubits to behave, we'll be amazed by the things quantum computers can do. But, alas, scientists have only implemented Shor's Algorithm for factoring integers on one number. 15. And hot damn, they got the factors right, 3 and 5. Yes, IAWAUGTOQC (I am writing an undergrad thesis on quantum computation).
I remember when I was in high school, we made cars out of blocks of balsa wood. It was a little like the Boy Scouts' Pinewood Derby, except more high tech. We'd make the cars as light as possible, paint them with dozens of coats of lacquer, put skinny wheels lubricated with graphite on them, and throw a CO2 cylinder in the back. One hit with a hammer and nail, and BAM! I think my car went over 70 mph. They had two eyelets on the bottom so they'd stay on the track made out of a single strand of fishing line. This appeals to all kinds of people who love to trick out cars, work with wood, or nerdy engineer types who come up with the best aerodynamic shape.
The linked .txt file is 7.1 MB, so it probably will take a while. The Google cache doesn't do the number justice. In fact, the cached number is divisible by 2...
Not exactly... As people have been mentioning with Space Ship One and the private space industry in particular, there is a lot of borrowed technology and knowledge from previous missions. A lot of the legwork has already been done. But you are absolutely correct in saying that competition is good. Ain't no good capitalist gonna let no pinko commie space rocket beat us to space again!!! (Holy crap that triple negative actually came out logically correct!!) I think it'll be interesting to see who gets to Mars first, China or non-government private enterprise. We're in for a good show no matter what.
Dammit slashdot!! You killed everyone's favorite election predictor site! Oh well, http://www.slate.com/ has a good map, similar to http://www.electoral-vote.com/. Let's see if MSN's servers are any better.
Nope, I'm in Oregon and we need all the Kerry votes we can get. I did, however, vote for a Socialist and a Libertarian for a couple state offices that were sure things for the incumbent Democrat. Voting your hopes is an art, and unless you're in CA, TX, or MA (along with some other out-of-play states), vote Bush the hell out. Anyone who lives in FL, OH, or MI especially, don't live in an idealistic dream land. A vote for a 3rd (or 4th or 5th) party candidate there IS a vote for Bush. Don't screw this up like swing-state Nader voters did in 2000. Go to http://www.electoral-vote.com/. If yr state is not a deep red or blue, VOTE KERRY. If you live in a state marked "Strong Bush" or "Strong Kerry" go ahead and vote for the candidate that you WANT in office, and not necessarily the one that has any shot in actually getting elected.
I'm in!
I'm from PDX as well. E-mail the monument scientist Peter Frenzen pfrenzen[AT]fs[DOT}fed{DoT}us and he'll be able to help you out with where to send your donations.
Now I can take pictures of Mt. St. Helens' glowing rocks! Before, my camera lens kept melting. With this new ceramic heat-resistant lens, my time on the volcano is only limited by the durability of my asbestos suit!
No, actually, it's quite safe. Coldwater Ridge Visitor's Center is located literally right on the edge of the blast zone for the big eruption. If I were standing there on a certain morning in 1980, yeah, I'd be toast, but this one is not going to be nearly as big (if it actually KABOOMs, which it may very well not). The Forest Service isn't stupid, that's why they closed Johnston Ridge Observatory, which is much closer to the crater. See this map http://www.fs.fed.us/gpnf/04mshnvm/global/images2/ mshrec.jpg of the area. The beige part is the blast zone (basically pea gravel, ash, and shrubbery), green is trees courtesy of Weyerhauser Lumber. Besides, there are about 15 satellite trucks parked in a lookout point nearby, each with a few hundred thousand bucks worth of very nice broadcasting equipment. If I trust the news guys, (which I do 110%!!!!!!!! ha, no...) it's safe. Either way, don't be such a wuss, get the hell up there and see it, it's beautiful.
Also, I climbed MSH the day before they shut down the mountain. There were a couple dozen earthquakes while I was on it, including one right when we were at the top. Of course I didn't know it at the time, only when I got home and checked the website. If you're close by, I highly recommend going, even if it doesn't blow while you're there. Supposedly (!!!) it's safe, plus you can see the lava dome and its new little buddy from the visitors center.
...less than a week ago, on Saturday Sept. 25th. There were a couple dozen quakes while I was on the mountain, but I didn't feel any of them as they were less than magnitude 2.5. Before we climbed, we were told not to look over the crater rim, as a steam explosion could hurl rocks at us. How counterproductive! Naturally, everyone looked anyway, because if there was an explosion, we wanted to see it. I climbed the mountain last year, and the weather was terrible. This time, it was perfectly clear, and I could actually see into the crater. (BIGGEST HOLE EVER) There were no signs of any gases escaping, although we could occasionally smell sulfur. It looked perfectly calm. Almost too calm... I live in Portland, and the winds say an ash cloud would head right towards us. I've got dust masks just in case...