The modern state of the US is easy for cowards to criticize. They don't realize that staying in Afghanistan and Iraq keeps the war in Afghanistan and Iraq
Care to provide any evidence that this is true? Because Icanprovideseveral instances that show that staying in Afghanistan and Iraq didn't do much of anything to contain terrorism. In fact, it seems a lot more likely that remaining in those places is at best, a waste of our troops lives and a lot of money, and at worst, is actually encouraging world-wide terrorism.
Oh, and here's another hint for you: "people who don't agree with you" != "cowards".
For shorter trips (say, up & down the east coast), train travel is the way to go. But cross country? I thought about booking an Amtrak trip from Northern VA to Des Moines one time. It would have taken days, and was more expensive than the equivalent airline ticket.
A "field" in math is an object that assigns a value to every point in space. A "magnetic field" assigns a vector that has to do with the amount of force experienced on an electrically charged particle moving with a certain velocity at that point. So it's not really "composed of" anything, any more than the earth's gravitational field is composed of anything. It's just a property.
What you're confusing with negative energy is relative energy--an object can be said to have negative potential energy if it has less potential energy than the arbitrary zero level. This is not the same thing as negative energy (any more than being in debt is having negative dollars, or being below 0 degrees Farenheit is having negative thermal energy).
In what sense is "being in debt" different from "having negative dollars"? If I have a credit card balance of $1000, and no assets, and then I make $100 and send them in the direction of my credit card account, the credit card balance will annihilate the $100 and reduce itself to $900. I think "negative potential energy" is a perfectly valid concept.
And it really does make your head hurt. From Newton (let's just leave Einstein out of this for now... please?): F=ma, and F = Gm1m2/r^2. Let's say that we're dealing with two bodies, one with mass m, and one with mass -m. So, substituting: the negative mass body feels -ma = Gm(-m)/r^2. The minus signs cancel, and the negative mass body is attracted to the positive mass body. But the positive mass body feels ma = Gm(-m)/^r2... so it's repelled by the negative mass body. In other words, set up these two bodies, and they'd chase each other across the universe at ever increasing speeds, forever. Which would appear to violate conservation of energy.
It gets even stranger when you consider that "mass" is not a completely well-defined term. You can talk about inertial mass, active gravitational mass (essentially, how much gravity a mass produces) and passive gravitational mass (how much force is produced when an object interacts with another object's gravity). For normal mass, it's been shown that these are all equivalent (at least, active and passive gravitational mass either have to be equivalent, or you have to give up conservation of momentum, and inertial and passive gravitational mass have to be equivalent, or general relativity doesn't work anymore). But it turns out that as long as you're speculating, you can go ahead and give these different kinds of mass different signs for the same body. Then you get even weirder results - for example, the negative mass might repel the positive mass, but still move toward it because such objects would accelerate in the opposite direction of forces applied!
There was also no theoretical reason for monopoles _to_ exist.
Viewed this way, there's no theoretical reason for ANYTHING to exist - the laws of physics don't REQUIRE there to be any matter. Particles are either allowed, or they aren't. And our experience has shown that particles that are allowed, exist. Except for magnetic monopoles. Which is kind of weird.
It should be noted that the "monopoles" discussed in TFA aren't "real" monopoles - they're quasiparticles that have the same properties as monopoles, but don't "really" exist. They're much the same as "holes" in electrically conductive materials - holes have the same electrical properties as positrons... but they aren't really positrons. The best evidence for now indicates that true magnetic monopoles don't exist, and we don't really know why.
... it founders on the usual issue - cost effectiveness. Smoke rounds already do this job very well, and they're bound to be a lot cheaper. They're also a lot easier to emplace (can you imagine firing one of these "black hole" deals out of an artillery piece, and having it get to its destination intact?). I wouldn't hold my breath waiting for this to show up on the battlefield.
It seems tremendously unlikely that this thing would be cheaper than what it aims to replace. There could possibly be a use for it in certain unusual situations - say, providing solar power to a spacecraft in the outer solar system. You might be able to get sufficient power without having to loft a giant mirror into space. But even in this case, it seems like the standard radiothermal generators would be a better choice.
... there's a simple (or if you prefer, simple simple) solution. And it's wrong. The issue is that many, many classes of computational problems are not amenable to breaking apart to solve in parallel. You pretty much have to do the steps in order. So parallelism only gets you so far.
I think it's a lot more likely that Moore's law (and technology expansion in general) is more likely to be following a logistic curve. It looks exponential for a while, but eventually levels out as you come upon fundamental limits to further growth.
Who said anything about whether we were "meant" to compute infinitely fast (whatever that even means)? This article is about whether it's possible. The answer, unsurprisingly, would appear to be no.
There are lots of problems that are susceptible to parallel computing techniques, and we've already built so-called "virtual supercomputers" to solve these problems - think seti@home. These virtual devices effectively produce some ungodly quantity of FLOPs. But there are other problems that are not so susceptible - if it can't be broken down into lots of identical parts, you essentially can't parallelize it. I don't think it's even questionable that there's any potential for improvement for these second category of problems - we pretty much know that you can't get there from here. This is much different from the problems you discuss: space travel was for the most part known to be a problem that could be solved with sufficiently advanced technology, even long before it was attempted, for example. Parallelizing problems is a whole different animal.
Back in the mists of prehistoric time, when I was a physics undergrad, we obviously took a lot of math and physics. Like 6 semesters of math, and god only knows how many physics courses. Somehow, we got by without ever needing a calculator - I didn't even own one. I'm not really sure why we need to use calculators during exams nowadays.
Whose correctness? That which can be deduced by repeatable scientific experiment, or subject to the rigours of proof beyond doubt in a court of law.
Are you seriously suggesting that I ought to be held at legal risk anytime I say anything that's not 1) provable by scientific experiment or 2) provable beyond doubt in court? If that was the case, I wouldn't be saying much at all, ever. An example: if I offered the opinion that say, there was no point in going to the US v. Honduras world cup match, as the US was going to wipe the field with them, I could get hauled into court by the Honduran team? After all, that statement is unprovable in any way (at least, before the match) and could harm the Honduran team by causing their revenue to drop. In fact, huge swaths of topics would be too risky to discuss at all: religion, politics, entertainment, anyone's love life - because most of what there is to say is unprovable, and when there's money involved, it's easy to find a way in which someone was at least potentially harmed.
Your policy sounds like a great recipe for no one to be able to communicate at all.
But you lot keep banging on about how bad the UK is...
This seems to be a hard concept for some people, but here's an attempt to explain: because he thinks the situation in the UK is bad does not necessarily mean he thinks the situation in the US is wonderful. In other words, they're both bad.
Is it? I consider myself a fairly typical computer user, and only a very tiny fraction of the stuff I print is web pages. Most of the documents I print are 1) Word docs, 2) Powerpoint presentations, 3) Excel spreadsheets, and 4) PDFs... and they hardly ever have URLs in them. I feel pretty safe in saying that the amount of toner I use on "//" is down in the noise, and the "//" virtually never causes a pagebreak.
I think that wasted print jobs - e.g. printing a huge job and then realizing you misspelled the title - is a far, far bigger cause of dead trees and wasted toner.
... and I still don't now. The guy doesn't like people making declarations - you might not share the opinion, but what's flamebait about it? Do we mod down anyone who uses naughty language, or what?
... if it weren't for all the damn stupid plugins. I'm on it, and appreciate finding out what's going on with friends and acquaintances in far-flung parts of the country. I don't appreciate logging into it and seeing dozens of entries about various people's status in Mafia Wars, Farmville, etc, etc.
Aren't most people getting to websites via 1) bookmarks 2) links from other sites 3) google searches, etc, etc? And for 90% of the remaining sites (https: being the obvious exception) you don't have to type the "http://" at all. And as for the dead trees... well, maybe if people were printing page after page of URLs, I could see it. But for real world print jobs, I have a hard time believing that those few extra characters are causing the job to spill over into an additional page very often.
We've basically already solved the issues shown in the video. Problems with too many windows: get a second monitor. It's not very expensive, and doesn't require me to learn a different desktop paradigm. You can also take advantage of various taskbar/Expose/Spaces type features, which (depending on your preferences) make the problem of window management a lot easier. Need more/better input "bandwidth"? Get a Mac laptop with multi-touch trackpad (if you're not a Mac person, ok, I can't imagine Windows is very far behind with this feature). But even this is a little dicey as it requires you to learn how to use the multi-touch interface - I've had an iPhone for about a year now, and I'm still not familiar with all the multi-touch gestures the system can do (it turns out that they're not really very "discoverable", at least for me).
It turns out that there's a reason we've stuck with our standard WIMP metaphor for interacting with our computers... it works really, really well. This effort strikes me as change for the sake of change.
Slashdot Mirror
Care to provide any evidence that this is true? Because I can provide several instances that show that staying in Afghanistan and Iraq didn't do much of anything to contain terrorism. In fact, it seems a lot more likely that remaining in those places is at best, a waste of our troops lives and a lot of money, and at worst, is actually encouraging world-wide terrorism.
Oh, and here's another hint for you: "people who don't agree with you" != "cowards".
For shorter trips (say, up & down the east coast), train travel is the way to go. But cross country? I thought about booking an Amtrak trip from Northern VA to Des Moines one time. It would have taken days, and was more expensive than the equivalent airline ticket.
A "field" in math is an object that assigns a value to every point in space. A "magnetic field" assigns a vector that has to do with the amount of force experienced on an electrically charged particle moving with a certain velocity at that point. So it's not really "composed of" anything, any more than the earth's gravitational field is composed of anything. It's just a property.
GP poster, I think you can consider yourself smacked down.
In what sense is "being in debt" different from "having negative dollars"? If I have a credit card balance of $1000, and no assets, and then I make $100 and send them in the direction of my credit card account, the credit card balance will annihilate the $100 and reduce itself to $900. I think "negative potential energy" is a perfectly valid concept.
Also: I don't think he really failed physics.
Although you don't run into it in any real-world situation, negative energy is useful in modeling the vacuum.
And it really does make your head hurt. From Newton (let's just leave Einstein out of this for now... please?): F=ma, and F = Gm1m2/r^2. Let's say that we're dealing with two bodies, one with mass m, and one with mass -m. So, substituting: the negative mass body feels -ma = Gm(-m)/r^2. The minus signs cancel, and the negative mass body is attracted to the positive mass body. But the positive mass body feels ma = Gm(-m)/^r2... so it's repelled by the negative mass body. In other words, set up these two bodies, and they'd chase each other across the universe at ever increasing speeds, forever. Which would appear to violate conservation of energy.
It gets even stranger when you consider that "mass" is not a completely well-defined term. You can talk about inertial mass, active gravitational mass (essentially, how much gravity a mass produces) and passive gravitational mass (how much force is produced when an object interacts with another object's gravity). For normal mass, it's been shown that these are all equivalent (at least, active and passive gravitational mass either have to be equivalent, or you have to give up conservation of momentum, and inertial and passive gravitational mass have to be equivalent, or general relativity doesn't work anymore). But it turns out that as long as you're speculating, you can go ahead and give these different kinds of mass different signs for the same body. Then you get even weirder results - for example, the negative mass might repel the positive mass, but still move toward it because such objects would accelerate in the opposite direction of forces applied!
I told you this stuff made your head hurt.
Viewed this way, there's no theoretical reason for ANYTHING to exist - the laws of physics don't REQUIRE there to be any matter. Particles are either allowed, or they aren't. And our experience has shown that particles that are allowed, exist. Except for magnetic monopoles. Which is kind of weird.
It should be noted that the "monopoles" discussed in TFA aren't "real" monopoles - they're quasiparticles that have the same properties as monopoles, but don't "really" exist. They're much the same as "holes" in electrically conductive materials - holes have the same electrical properties as positrons... but they aren't really positrons. The best evidence for now indicates that true magnetic monopoles don't exist, and we don't really know why.
... it founders on the usual issue - cost effectiveness. Smoke rounds already do this job very well, and they're bound to be a lot cheaper. They're also a lot easier to emplace (can you imagine firing one of these "black hole" deals out of an artillery piece, and having it get to its destination intact?). I wouldn't hold my breath waiting for this to show up on the battlefield.
It seems tremendously unlikely that this thing would be cheaper than what it aims to replace. There could possibly be a use for it in certain unusual situations - say, providing solar power to a spacecraft in the outer solar system. You might be able to get sufficient power without having to loft a giant mirror into space. But even in this case, it seems like the standard radiothermal generators would be a better choice.
... there's a simple (or if you prefer, simple simple) solution. And it's wrong. The issue is that many, many classes of computational problems are not amenable to breaking apart to solve in parallel. You pretty much have to do the steps in order. So parallelism only gets you so far.
[citation needed]. Who were these physicists who allegedly said this?
I think it's a lot more likely that Moore's law (and technology expansion in general) is more likely to be following a logistic curve. It looks exponential for a while, but eventually levels out as you come upon fundamental limits to further growth.
Who said anything about whether we were "meant" to compute infinitely fast (whatever that even means)? This article is about whether it's possible. The answer, unsurprisingly, would appear to be no.
I'd like to subscribe to your newsletter.
There are lots of problems that are susceptible to parallel computing techniques, and we've already built so-called "virtual supercomputers" to solve these problems - think seti@home. These virtual devices effectively produce some ungodly quantity of FLOPs. But there are other problems that are not so susceptible - if it can't be broken down into lots of identical parts, you essentially can't parallelize it. I don't think it's even questionable that there's any potential for improvement for these second category of problems - we pretty much know that you can't get there from here. This is much different from the problems you discuss: space travel was for the most part known to be a problem that could be solved with sufficiently advanced technology, even long before it was attempted, for example. Parallelizing problems is a whole different animal.
Back in the mists of prehistoric time, when I was a physics undergrad, we obviously took a lot of math and physics. Like 6 semesters of math, and god only knows how many physics courses. Somehow, we got by without ever needing a calculator - I didn't even own one. I'm not really sure why we need to use calculators during exams nowadays.
Are you seriously suggesting that I ought to be held at legal risk anytime I say anything that's not 1) provable by scientific experiment or 2) provable beyond doubt in court? If that was the case, I wouldn't be saying much at all, ever. An example: if I offered the opinion that say, there was no point in going to the US v. Honduras world cup match, as the US was going to wipe the field with them, I could get hauled into court by the Honduran team? After all, that statement is unprovable in any way (at least, before the match) and could harm the Honduran team by causing their revenue to drop. In fact, huge swaths of topics would be too risky to discuss at all: religion, politics, entertainment, anyone's love life - because most of what there is to say is unprovable, and when there's money involved, it's easy to find a way in which someone was at least potentially harmed.
Your policy sounds like a great recipe for no one to be able to communicate at all.
This seems to be a hard concept for some people, but here's an attempt to explain: because he thinks the situation in the UK is bad does not necessarily mean he thinks the situation in the US is wonderful. In other words, they're both bad.
Is it? I consider myself a fairly typical computer user, and only a very tiny fraction of the stuff I print is web pages. Most of the documents I print are 1) Word docs, 2) Powerpoint presentations, 3) Excel spreadsheets, and 4) PDFs... and they hardly ever have URLs in them. I feel pretty safe in saying that the amount of toner I use on "//" is down in the noise, and the "//" virtually never causes a pagebreak.
I think that wasted print jobs - e.g. printing a huge job and then realizing you misspelled the title - is a far, far bigger cause of dead trees and wasted toner.
For pete's sake, even FAX MACHINES haven't gone away. Why would we expect e-mail to?
Resistance is futile!
... and I still don't now. The guy doesn't like people making declarations - you might not share the opinion, but what's flamebait about it? Do we mod down anyone who uses naughty language, or what?
... if it weren't for all the damn stupid plugins. I'm on it, and appreciate finding out what's going on with friends and acquaintances in far-flung parts of the country. I don't appreciate logging into it and seeing dozens of entries about various people's status in Mafia Wars, Farmville, etc, etc.
Aren't most people getting to websites via 1) bookmarks 2) links from other sites 3) google searches, etc, etc? And for 90% of the remaining sites (https: being the obvious exception) you don't have to type the "http://" at all. And as for the dead trees... well, maybe if people were printing page after page of URLs, I could see it. But for real world print jobs, I have a hard time believing that those few extra characters are causing the job to spill over into an additional page very often.
We've basically already solved the issues shown in the video. Problems with too many windows: get a second monitor. It's not very expensive, and doesn't require me to learn a different desktop paradigm. You can also take advantage of various taskbar/Expose/Spaces type features, which (depending on your preferences) make the problem of window management a lot easier. Need more/better input "bandwidth"? Get a Mac laptop with multi-touch trackpad (if you're not a Mac person, ok, I can't imagine Windows is very far behind with this feature). But even this is a little dicey as it requires you to learn how to use the multi-touch interface - I've had an iPhone for about a year now, and I'm still not familiar with all the multi-touch gestures the system can do (it turns out that they're not really very "discoverable", at least for me).
It turns out that there's a reason we've stuck with our standard WIMP metaphor for interacting with our computers... it works really, really well. This effort strikes me as change for the sake of change.