calling something a particle or a quasi-particle doesn't really matter.
It does in several senses.
1) Does it exist in vacuum? If it does, it probably has cosmological significance. Quasi-particles, being matter-bound, do not.
2) Is it composite? Reductionism is a good trick that has served physics well for several hundred years. When we get to something that we can't figure out how to take apart we call it "elementary" and start using it as the foundation for everything else. Quasi-particles are composite.
So there are two obvious and large differences between quasi-particles and elementary particles. It may be that what we think of as elementary particles are actually quasi-particles in the vacuum, but if we discovered that it would be extremely interesting precisely because quasi-particles and elementary particles are so completely different.
As you find them in a standard text book, they do exactly that
In manifestly co-variant form, which is by far the more likely way for physicists to think about them, the lack of magnetic charge gets hidden in an abstract four-vector.
The form of the equations--their invariance under Lorentz transformations--is a far more important feature of Maxwell's equations than whether or not some particular vector component is strictly zero. If we were to find true magnetic monopoles the transformation properties of the equations would not change and physicists would happily go on calling them "Maxwell's equations", because that is what they still would be.
For both historical and practical reasons we teach undergrads Maxwell's equations as vanilla differential equations, which is unfortunate because a) it fixates them on irrelevant aspects of that notation and b) it hides the deep and profound elegance of their underlying mathematical structure.
Whenever I see someone refer to their purported opponent in abstract like this, be it "the enemy" or "the terrorists" or even "al Qaeda" or "the Germans", I get the feeling that they are muttering like a delusional paranoid about the ghosts and shadows that haunt their brain.
Name names. Hitler was "the enemy" and "anyone wearing a German uniform" might have counted as "the enemy" during WWII, but saying it was a war against "the Germans" would be false, because many Germans were opposed to the war.
Insurgents have always played games with identity, and occupying powers have always let themselves get sucked into a miasma of paranoia because of it, which ultimately contributes to their loss. Nothing is more important than having a crisp, clear definition of who the enemy actually is, and if you cannot supply that then the appropriate tool for redress is not the military, but the police, whose primary function is to identify the perpetrator, not indiscriminately shoot people.
Ergo, the primary role in counter-terrorism ought to be given to the police, not the military. If the FBI had had 10% of the budget of the US military 9/11 would never have happened.
Would building three 735kV lines really cost more than building a superconductive conduit?
No, conventional high voltage lines would be much cheaper, and the loads they are talking about are moderate at best, especially over such short distances. The need for AC/DC/AC conversion to do phase matching does make HTS connections plausible, but the proposal still smells: These guys are getting a sweetheart land deal and the fingerprints of government infrastructure contracts are all over it. Under those circumstances you (for a certain value of "you", which does not include taxpayers, power producers or power consumers) want it to be as expensive as possible, because that's how you suck the maximum amount out of the public trough.
I'd love to be non-cynical about this, but the odds of the engineering use of superconductors in this case being economically justified look pretty small.
And they just don't have the time to go over everyones code.
And don't have the competency to write some static screening tools that will reject all the XSS stuff etc?
And don't have the legal chops to write contractual language that will let them pwn your ass if you do submit LP's with XSS etc in them?
While putting a paywall up does have the advantage of creating a somewhat self-policing marketplace in this regard, my sense is that a $500 fee would do the same job and not exclude smaller players. It isn't the fact of the fee but its size that provides the evidence of Apple's malicious intent in preventing iTunes users from having access to LPs from smaller players.
Programs that work fine with small amounts of data explode when you get them into production.
As the OP pointed out, testing is your friend.
I'm using wxPython on a project that has hundreds of items in a tree. No problems, although it's slower than I'd like, mostly due to interface overheads (pushing stuff through SWIG is expensive, and if I were to improve wxPython in any way it would be to add "batch" interfaces that would let me push a whole wack of stuff through to the C++ side with a single call.)
I've used wxWidgets on Windows for years, after years of Qt, and for what I do wx is great: solid, well-documented and extremely functional. Qt lost me with their license shenanigans a few years back, when TrollTech broke the lib up into parts and started charging for every little piece of it instead of selling the bundle. Fortunately, wx was just about ready for prime time about then--if you used wx more than a few years ago I can understand your frustrations, because it was really not ready for production code, but today it is definitely worth checking out unless you're already invested in Qt or really need to ship statically linked (it's my understanding that Qt is now LGPL).
"Iran has so much oil, why would they care about nuclear energy?"
For the same reason Canada does.
Canada has almost as much oil as Iran and has a large civil nuclear power program. Here in Ontario we get about half our electricity from nuclear power, despite all that oil in Alberta and elsewhere.
So anyone bringing this point up about Iran is just demonstrating their complete ignorance of the world, and disqualifying themselves from being taken seriously regarding American foreign policy.
By the way, Canada has more tort per capita than the U.S.
I assume you mean medical malpractice suits, as it would be bizzare and disingenous to impute any other meaning to "tort" in the context of this discussion. On that basis, your claim is false:
Canada, with 10% of the population of the US, had just over 1000 malpractice claims in 2004. The US had 40% more per capita at 1400. I very much doubt that difference has been erased in the past five years.
Nor are award sizes in Canada significantly greater than in the US. The only big difference is that our (Canadian) medical malpractice insurance rates are somewhat lower, although still touching US highs in some areas.
I agree that tort reform is not the primary issue with the US "health care" "system", but it is not true that Canada has significantly higher medical malpractice costs: our insurance costs are lower, our rate of litigation is lower, and our payouts are comparable.
Therefore, they are describing something that is different than the Prius, and the Patent Troll court in Texas strikes again!
Yeah, the grant date on the patent is July 2008, and the application date is May 8, 2006, so unless there has been a very significant modification to the Prius drive-train since it must not be covered by the patent. And since the first CLAIM of the patent it egregiously broad (the summary and associated docs mean nothing, the claims mean everything) and describes nothing novel or interesting that isn't already present in a Prius, it is very hard to believe that this will hold up for very long.
But of course, in the United States, the process is the punishment. The legal system is so expensive and capricious that anyone coming into contact with it is going to get screwed one way or the other, mostly by their own lawyers.
Any ideas what happens to reports on cops committing crimes?
I'd say they disappear down the memory hole, but users will be able to capture the video they are using locally, and repost on YouTube for fun and profit.
Ergo, this program will be shut down within weeks as it reveals cops committing crimes. Either that, or the feeds will be scrubbed of all police presence "for the protection of our hardworking constables on the street" prior to distributing them.
and then proposing to build and accelerate something really really heavy out of the solar system at a meaningful speed
I'm not suggesting that, and neither is the guy who's proposing this experiment, at least the way I'm reading it. I'm proposing instrument packages that have a mass of maybe a gram. Who knows what such a thing might be able to do in a few decades if we keep on making things smaller and lighter.
A gram is not actually that much to get up to relativistic speeds if you don't have to haul your fuel with you. Remember, a smallish nuclear power plant (1 GW, say) is converting 1 g to energy every twelve hours or so, and to first order the amount of energy required to get a mass up to a respectable fraction of c is that object's mass converted to energy.
So the power requirements for a relativistic interstellar micro-probe aren't out of this world, although the power plant itself would probably be built on lunar farside. What's required is a way to deliver the power to the probe. This guy thinks he has a more efficient way of doing that. Fair enough: certainly worth testing, and certainly worth wondering how it might be applied to practical interstellar exploration.
It might not happen for centuries. But never? That's a long time.
The ONLY exception to this is the "solar sail" concept, which relies on an external source of propulsion.
I believe the idea here is to have a particle accelerator in orbit that will be fired past the spacecraft it is accelerating, so it is analogous to a laser-pumped solar sail. It's also best to think of this as a potential tool for accelerating really low-mass instrument packages intended to do fly-bys of nearby stars, which could be scientifically useful.
The rest of your post sounds remarkably like statements by people back in the '70's that we'd never be able to image the disk of even nearby stars, much less discover or image planets around them.
It may be that what the author is proposing is impossible. There are a number of things in the paper that look highly sketchy to me, but GR ain't my field. Even so, while this method of acceleration for interstellar exploration may not work, the one method that is certain not to work is never bothering to try.
When you annihilate it you should get about three to the minus ten joules
Fixed that for you. Protons have a mass of 1.7E-27 kg, c = 3E8 m/s, so 2*mc**2 ~ 3E-10 (the factor of two from the anti-proton).
The article itself is clearly written for an audience of ignorant yobs, and that's fair enough: ignorant yobs need a gateway into the scientific world as much as anyone. But it ain't "news for nerds", because nerds know that matter-anti-matter colliders have been around for decades.
it would be kind of hard for the Odyssey to be written a century or two before the invention of the modern Greek alphabet.
Fixed that for you. The Greeks wrote in Linear B prior the the Greek Dark Age. Admittedly, in 900 BC they weren't writing anything that we know of, although it's possible that oral versions of stories that resulted in the Homeric poems have their origins in that time, much as the stories of King Arthur have their origins centuries before Mallory et al.
Now all that's required is for some even more pedantic person to reply to this pointing out that the classical Greek alphabet differs from the modern one.
So, if I had a sympathetic view toward ID, at any time, I am not entitled, somehow, to ask a purely scientific question?
You're perfectly entitled to do so, and when you come up with one please ask it.
Is it significant, from a purely scientific standpoint, if in 10 years Common Descent will no longer be true? YES.
Nope. What currently active research questions depend on the truth or falsity of common descent? For example, most scientists currently believe that there are other life systems in the universe, so on that basis we're pretty sure common descent is false today: there are living organisms on a planet in the life zone of some other star that do not have common ancestry with us.
So what? The falsity of common descent due to life on other planets has exactly zero impact on scientific questions of interest regarding life on Earth. Likewise, the possible falsity of common descent at some hypothetical time in the future has exactly zero impact on scientific questions about life in the past.
If we were to find that common descent was false in the past it would be of scientific interest, because it would allow us to study a situation where evolution by variation and natural selection occurred involving two independent life systems. This seems to me quite probable: that abiogensis occurred multiple times and we are the descendents of the particular system that got the monopoly. Particular means of genetic encoding do form "natural monopolies" that will tend toward the total domination of one at the expense of all others. Unfortunately, if it happened, it did so too early to leave any meaningful evidence.
Your question as stated has no scientific interest, and yet for some reason you keep asserting that it does. As only someone who has no understanding of the actual role common descent plays in the scientific investigation of the orgins of the diversity of life would think that, it is no suprise that the people here responding to you have infered that you have no understanding of the role common descent plays in the scientific investigation of the origins of the diversity of life. That is, you are behaving exactly like a typical creationist/IDtroll, and are being treated accordingly.
If everybody followed the "I'll just statically link everything" the average Windows computer would need 32G of memory just to function (exaggerated to make a point).
Wanna provide some data for that claim? And any guesses as to the number of people who ship private versions of the DLLs they need to ensure their app behaves properly because it depends on bugs in that specific DLL version? In my experience that's a pretty common move for anything above a "Hello World" application.
Also, a number of people the GP was responding to were making points about how long it would take to download stuff, so I hope you replied to them as well, pointing out what dummies they are.
When I used dynamic linking, to simplify installation for the user, I had to also distribute the full DLLs along (they would not be installed if they already exist on the target machine), even when I used only a small portion of their functionality. Consequently, my installers were always SMALLER when using static linking.
Thank you. One of the basic laws of programming is "no optimization without quantification", and the posters above who are claiming "but if you statically linked things would be big!" are not offering any actual data. The reality you describe is all too familiar: dynamically linked applications that ship with thier own private copy of the DLLs to ensure they don't step on the existing ones, and that depend on the bugs/features in those specific versions.
To take an extreme example, I'm shipping an app right now that installs its own private JRE version because a third-party driver I'm stuck with requires that one specific (now ancient and unsupported) runtime or it leaks memory and dies on a regular basis (installing the private JRE on a specific relative path where the driver will find it is recommended by the manufacturer, who are hardware people and whose software support group is clearly staffed by drunken monkeys.)
So the baseless claim that "dynamic linking makes it smaller" needs quantification: real world empirical data to back it up. Otherwise it is just hot air. And in a world where bandwidth is cheap and hard drives are huge, even if statically linked exe's are a bit bigger, I'm willing to pay that price to ensure that my users always get to run the code I ship, rather than some other code that happens to be on their machines.
If used consistently the SxS stuff could have created a world where users could have multiple copies of common DLLs and we wouldn't have to worry about shipping private copies, but in the real world dynamic linking means that users wind up with dozens of copies of common DLLs sitting in different directories, just in case someone else steps on the copies in the standard path with new versions that they haven't tested against.
Dynamic linking is an example of pre-mature optimization, and as such should be avoided unless there is a compelling quantitative reason for using it, and only then for non-critical systems, where the undefined behaviour that may result when new versions of libs are installed in the standard path doesn't matter.
Remember: if you are installing private copies of common DLLs or using SxS to allow multiple public copies of common DLLs to cohabit nicely, you should be statically linking your code. Otherwise you installer is bigger than it needs to be because it contains whole DLLs are part of the redist package, rather than just the bits you need compiled into your app.
hose centrifuges are not easy to make (they spin up to 90,000 RPM) and something as a fingerprint on one of them will make it shatter when it's spinning that fast.
Gas centrifuge technology, which has been available since the '80's, gets around most of this problem. It was predicted at the time that it would be hugely proliferating because it would make uranium enrichment relatively cheap and easy. Iran's programme is just proof of this.
As other posters here have pointed out, making a uranium bomb is incredibly easy. Little Boy was detonated operationally without the design ever being tested. Fat Man was a plutonium implosion design, and it the Trinity test was run to ensure it would actually work.
Also, remember that plutonium implosion was tricky because of the exact timing requirements... in 1945. The trigger switches used involved TUBES of one kind or another. In these days of high-speed solid state electronics, where off-the-shelf chips with 1 ns switching times can be bought for a few dollars and drive a few cm of transmission line with ease, the problem of plutonium implosion is vastly easier to solve.
Making a big deal out of some people in Iran knowing how to build a nuclear bomb is silly, and plays in ignorant stereotypes of how difficult it is to actually do the job. Canada has the knowledge to build a nuclear bomb too, and has for decades. We'll only build one if we decide the nation of idiots to the south of us has gone completely off the rails, and starts trying to overthrow our democratically elected government, as it did in Iran back in the '50's. On that basis, if I were an Iranian, I'd bloody well want my country to have the Bomb.
On the other hand, Canada also has a large peaceful nuclear programme, despite sitting on a whole lot of oil. So anyone who suggests that Iran doesn't want a peaceful nuclear programme just because they have oil is clearly an anti-empirical idiot.
I'm not aware of any version control system that does this. Is anyone else?
Huh? You're not aware of any version control systems at all? Strictly speaking it is the particular diff tool rather than the VCS that matters in this case, but every diff tool I've ever worked with has options specific to suppressing exactly the kind of trivial differences you've inexplicably cited as a "big problem."
Translating these results into some meaningful treatment for normal adults is highly likely to face a lot of roadblocks and complexities.
I generally agree with this, but there are two things that raise this above the usual "cures cancer in mice" hype.
The first is that these are xenografts, which means they're dealing with authentic human cancers, which are in general far tougher to kill than cancers in other species (we are tuned up for great longevity for obvious evolutionary reasons, and therefore incredibly cancer resistant compared to most species, meaning the few human cancers that do become malignant are incredibly hard to kill.) A quick look at the paper shows they've used multiple cell lines for the xenographs, which is also good.
The second is that there is already evidence of reduced cancer rates in humans taking this stuff (pancreatic cancer only, and diabetics only, so limited but suggestive data.)
and it really is one of the few on the topic that I'd honestly say has results that can fairly be characterized as "dramatic".
You're right: they may lead to another dead end. We've seen a lot of those before. But this looks like solid research and very promising results. Clinical trials on humans are in the works, with patient enrollment starting perhaps as soon as next year.
And his first sentence is a a lie. Anyone intelligent enough to form a sentence is capable of reasoning out the answers to the "questions" he is asking. That he deliberately injects those questions (whatever they are--I didn't actually open his comment, only the replies to it) into this forum is evidence that he has an aggressive ideological malignancy.
We need congressional elections similar to the EU parliament elections where parties get membership based on the % of votes or a smaller federal government.
Why do you want to give private organizations a given fraction of parliament? Parliament should represent people, not parties, and anyone who tells you that their MP is too incompetent to represent their constituents is telling you their MP needs to be replaced. Representational democracy has worked for centuries without anything like the level of partisan capture that exists today, so claims that there are unsolvable problems with it just reflect the ignorance or malicious intent of the person making the argument.
The world needs less partisan representation, and electoral reform won't get off the ground until the people pushing it realize that the only effective reform will be one that reduces partisan power, not increases it by embedding the existence of parties in the electoral process. I realize that the parties are already deeply embedded in the electoral process in the US, which is one of the main reasons why the American electoral system is so much more broken than virtually anywhere else in the world.
Electoral reforms have been raised in several Canadian provinces in recent years, and while none of them have passed the proposals in British Columbia, which were less partisan, came a lot closer than the insanely partisan system Ontario voters were presented with.
n fact, would this imply that there is a large scale migration of rock from the sunward side of the planet to that opposed to the sun (and would this in turn alter the fundamental planet shape? I envisage dinnerplate planets...)
I briefly entertained the same fantasy--I even wondered if this could destablize the tidal locking by transporting mass from the point closest to the sun to more distant points, which on reflection seems highly unlikely.
It is possible that the processes described in the article result in a bit of a flat spot close to the star and a mountainous bulge of scree along the terminator, but with lava to transport molten rock across the surface, and rock being pretty plastic at such high temperatures anyway, it is unlikely that anything so extreme as a dinner-plate shape could take form, which is a damned shame.
Because people desperately need to look clever by insisting that their own idiotic ideas about the right way to use a technology is the only conceivable way.
Many of the apps we used (hello, Oracle Colaboration suite, looking at you) require really messing with system files to make work decent. This makes other programs very unhappy, so apps like these really need to run on their own box.
This makes sense now: incompetent server developers are the driver behind this aspect of VMs. Other aspects are independent of this, but a lot of people responding here have simply taken for granted that most servers are written by monkeys, and are therefore unable to play nicely with others.
I kind of figured this was the case, having written server code (back in the '90's) and seen the gyrations my team went through to make sure we were able to run without requiring a stepped-on environment, but I found it hard to believe that badly-written server code had become so common as to make virtualization the only viable solution.
Slashdot Mirror
calling something a particle or a quasi-particle doesn't really matter.
It does in several senses.
1) Does it exist in vacuum? If it does, it probably has cosmological significance. Quasi-particles, being matter-bound, do not.
2) Is it composite? Reductionism is a good trick that has served physics well for several hundred years. When we get to something that we can't figure out how to take apart we call it "elementary" and start using it as the foundation for everything else. Quasi-particles are composite.
So there are two obvious and large differences between quasi-particles and elementary particles. It may be that what we think of as elementary particles are actually quasi-particles in the vacuum, but if we discovered that it would be extremely interesting precisely because quasi-particles and elementary particles are so completely different.
As you find them in a standard text book, they do exactly that
In manifestly co-variant form, which is by far the more likely way for physicists to think about them, the lack of magnetic charge gets hidden in an abstract four-vector.
The form of the equations--their invariance under Lorentz transformations--is a far more important feature of Maxwell's equations than whether or not some particular vector component is strictly zero. If we were to find true magnetic monopoles the transformation properties of the equations would not change and physicists would happily go on calling them "Maxwell's equations", because that is what they still would be.
For both historical and practical reasons we teach undergrads Maxwell's equations as vanilla differential equations, which is unfortunate because a) it fixates them on irrelevant aspects of that notation and b) it hides the deep and profound elegance of their underlying mathematical structure.
including the enemy
Who exactly is "the enemy"?
Whenever I see someone refer to their purported opponent in abstract like this, be it "the enemy" or "the terrorists" or even "al Qaeda" or "the Germans", I get the feeling that they are muttering like a delusional paranoid about the ghosts and shadows that haunt their brain.
Name names. Hitler was "the enemy" and "anyone wearing a German uniform" might have counted as "the enemy" during WWII, but saying it was a war against "the Germans" would be false, because many Germans were opposed to the war.
Insurgents have always played games with identity, and occupying powers have always let themselves get sucked into a miasma of paranoia because of it, which ultimately contributes to their loss. Nothing is more important than having a crisp, clear definition of who the enemy actually is, and if you cannot supply that then the appropriate tool for redress is not the military, but the police, whose primary function is to identify the perpetrator, not indiscriminately shoot people.
Ergo, the primary role in counter-terrorism ought to be given to the police, not the military. If the FBI had had 10% of the budget of the US military 9/11 would never have happened.
Would building three 735kV lines really cost more than building a superconductive conduit?
No, conventional high voltage lines would be much cheaper, and the loads they are talking about are moderate at best, especially over such short distances. The need for AC/DC/AC conversion to do phase matching does make HTS connections plausible, but the proposal still smells: These guys are getting a sweetheart land deal and the fingerprints of government infrastructure contracts are all over it. Under those circumstances you (for a certain value of "you", which does not include taxpayers, power producers or power consumers) want it to be as expensive as possible, because that's how you suck the maximum amount out of the public trough.
I'd love to be non-cynical about this, but the odds of the engineering use of superconductors in this case being economically justified look pretty small.
And they just don't have the time to go over everyones code.
And don't have the competency to write some static screening tools that will reject all the XSS stuff etc?
And don't have the legal chops to write contractual language that will let them pwn your ass if you do submit LP's with XSS etc in them?
While putting a paywall up does have the advantage of creating a somewhat self-policing marketplace in this regard, my sense is that a $500 fee would do the same job and not exclude smaller players. It isn't the fact of the fee but its size that provides the evidence of Apple's malicious intent in preventing iTunes users from having access to LPs from smaller players.
Programs that work fine with small amounts of data explode when you get them into production.
As the OP pointed out, testing is your friend.
I'm using wxPython on a project that has hundreds of items in a tree. No problems, although it's slower than I'd like, mostly due to interface overheads (pushing stuff through SWIG is expensive, and if I were to improve wxPython in any way it would be to add "batch" interfaces that would let me push a whole wack of stuff through to the C++ side with a single call.)
I've used wxWidgets on Windows for years, after years of Qt, and for what I do wx is great: solid, well-documented and extremely functional. Qt lost me with their license shenanigans a few years back, when TrollTech broke the lib up into parts and started charging for every little piece of it instead of selling the bundle. Fortunately, wx was just about ready for prime time about then--if you used wx more than a few years ago I can understand your frustrations, because it was really not ready for production code, but today it is definitely worth checking out unless you're already invested in Qt or really need to ship statically linked (it's my understanding that Qt is now LGPL).
"Iran has so much oil, why would they care about nuclear energy?"
For the same reason Canada does.
Canada has almost as much oil as Iran and has a large civil nuclear power program. Here in Ontario we get about half our electricity from nuclear power, despite all that oil in Alberta and elsewhere.
So anyone bringing this point up about Iran is just demonstrating their complete ignorance of the world, and disqualifying themselves from being taken seriously regarding American foreign policy.
By the way, Canada has more tort per capita than the U.S.
I assume you mean medical malpractice suits, as it would be bizzare and disingenous to impute any other meaning to "tort" in the context of this discussion. On that basis, your claim is false:
http://www.chsrf.ca/mythbusters/html/myth21_e.php
Canada, with 10% of the population of the US, had just over 1000 malpractice claims in 2004. The US had 40% more per capita at 1400. I very much doubt that difference has been erased in the past five years.
Nor are award sizes in Canada significantly greater than in the US. The only big difference is that our (Canadian) medical malpractice insurance rates are somewhat lower, although still touching US highs in some areas.
I agree that tort reform is not the primary issue with the US "health care" "system", but it is not true that Canada has significantly higher medical malpractice costs: our insurance costs are lower, our rate of litigation is lower, and our payouts are comparable.
Therefore, they are describing something that is different than the Prius, and the Patent Troll court in Texas strikes again!
Yeah, the grant date on the patent is July 2008, and the application date is May 8, 2006, so unless there has been a very significant modification to the Prius drive-train since it must not be covered by the patent. And since the first CLAIM of the patent it egregiously broad (the summary and associated docs mean nothing, the claims mean everything) and describes nothing novel or interesting that isn't already present in a Prius, it is very hard to believe that this will hold up for very long.
But of course, in the United States, the process is the punishment. The legal system is so expensive and capricious that anyone coming into contact with it is going to get screwed one way or the other, mostly by their own lawyers.
Any ideas what happens to reports on cops committing crimes?
I'd say they disappear down the memory hole, but users will be able to capture the video they are using locally, and repost on YouTube for fun and profit.
Ergo, this program will be shut down within weeks as it reveals cops committing crimes. Either that, or the feeds will be scrubbed of all police presence "for the protection of our hardworking constables on the street" prior to distributing them.
and then proposing to build and accelerate something really really heavy out of the solar system at a meaningful speed
I'm not suggesting that, and neither is the guy who's proposing this experiment, at least the way I'm reading it. I'm proposing instrument packages that have a mass of maybe a gram. Who knows what such a thing might be able to do in a few decades if we keep on making things smaller and lighter.
A gram is not actually that much to get up to relativistic speeds if you don't have to haul your fuel with you. Remember, a smallish nuclear power plant (1 GW, say) is converting 1 g to energy every twelve hours or so, and to first order the amount of energy required to get a mass up to a respectable fraction of c is that object's mass converted to energy.
So the power requirements for a relativistic interstellar micro-probe aren't out of this world, although the power plant itself would probably be built on lunar farside. What's required is a way to deliver the power to the probe. This guy thinks he has a more efficient way of doing that. Fair enough: certainly worth testing, and certainly worth wondering how it might be applied to practical interstellar exploration.
It might not happen for centuries. But never? That's a long time.
The ONLY exception to this is the "solar sail" concept, which relies on an external source of propulsion.
I believe the idea here is to have a particle accelerator in orbit that will be fired past the spacecraft it is accelerating, so it is analogous to a laser-pumped solar sail. It's also best to think of this as a potential tool for accelerating really low-mass instrument packages intended to do fly-bys of nearby stars, which could be scientifically useful.
The rest of your post sounds remarkably like statements by people back in the '70's that we'd never be able to image the disk of even nearby stars, much less discover or image planets around them.
It may be that what the author is proposing is impossible. There are a number of things in the paper that look highly sketchy to me, but GR ain't my field. Even so, while this method of acceleration for interstellar exploration may not work, the one method that is certain not to work is never bothering to try.
When you annihilate it you should get about three to the minus ten joules
Fixed that for you. Protons have a mass of 1.7E-27 kg, c = 3E8 m/s, so 2*mc**2 ~ 3E-10 (the factor of two from the anti-proton).
The article itself is clearly written for an audience of ignorant yobs, and that's fair enough: ignorant yobs need a gateway into the scientific world as much as anyone. But it ain't "news for nerds", because nerds know that matter-anti-matter colliders have been around for decades.
it would be kind of hard for the Odyssey to be written a century or two before the invention of the modern Greek alphabet.
Fixed that for you. The Greeks wrote in Linear B prior the the Greek Dark Age. Admittedly, in 900 BC they weren't writing anything that we know of, although it's possible that oral versions of stories that resulted in the Homeric poems have their origins in that time, much as the stories of King Arthur have their origins centuries before Mallory et al.
Now all that's required is for some even more pedantic person to reply to this pointing out that the classical Greek alphabet differs from the modern one.
So, if I had a sympathetic view toward ID, at any time, I am not entitled, somehow, to ask a purely scientific question?
You're perfectly entitled to do so, and when you come up with one please ask it.
Is it significant, from a purely scientific standpoint, if in 10 years Common Descent will no longer be true? YES.
Nope. What currently active research questions depend on the truth or falsity of common descent? For example, most scientists currently believe that there are other life systems in the universe, so on that basis we're pretty sure common descent is false today: there are living organisms on a planet in the life zone of some other star that do not have common ancestry with us.
So what? The falsity of common descent due to life on other planets has exactly zero impact on scientific questions of interest regarding life on Earth. Likewise, the possible falsity of common descent at some hypothetical time in the future has exactly zero impact on scientific questions about life in the past.
If we were to find that common descent was false in the past it would be of scientific interest, because it would allow us to study a situation where evolution by variation and natural selection occurred involving two independent life systems. This seems to me quite probable: that abiogensis occurred multiple times and we are the descendents of the particular system that got the monopoly. Particular means of genetic encoding do form "natural monopolies" that will tend toward the total domination of one at the expense of all others. Unfortunately, if it happened, it did so too early to leave any meaningful evidence.
Your question as stated has no scientific interest, and yet for some reason you keep asserting that it does. As only someone who has no understanding of the actual role common descent plays in the scientific investigation of the orgins of the diversity of life would think that, it is no suprise that the people here responding to you have infered that you have no understanding of the role common descent plays in the scientific investigation of the origins of the diversity of life. That is, you are behaving exactly like a typical creationist/IDtroll, and are being treated accordingly.
If everybody followed the "I'll just statically link everything" the average Windows computer would need 32G of memory just to function (exaggerated to make a point).
Wanna provide some data for that claim? And any guesses as to the number of people who ship private versions of the DLLs they need to ensure their app behaves properly because it depends on bugs in that specific DLL version? In my experience that's a pretty common move for anything above a "Hello World" application.
Also, a number of people the GP was responding to were making points about how long it would take to download stuff, so I hope you replied to them as well, pointing out what dummies they are.
When I used dynamic linking, to simplify installation for the user, I had to also distribute the full DLLs along (they would not be installed if they already exist on the target machine), even when I used only a small portion of their functionality. Consequently, my installers were always SMALLER when using static linking.
Thank you. One of the basic laws of programming is "no optimization without quantification", and the posters above who are claiming "but if you statically linked things would be big!" are not offering any actual data. The reality you describe is all too familiar: dynamically linked applications that ship with thier own private copy of the DLLs to ensure they don't step on the existing ones, and that depend on the bugs/features in those specific versions.
To take an extreme example, I'm shipping an app right now that installs its own private JRE version because a third-party driver I'm stuck with requires that one specific (now ancient and unsupported) runtime or it leaks memory and dies on a regular basis (installing the private JRE on a specific relative path where the driver will find it is recommended by the manufacturer, who are hardware people and whose software support group is clearly staffed by drunken monkeys.)
So the baseless claim that "dynamic linking makes it smaller" needs quantification: real world empirical data to back it up. Otherwise it is just hot air. And in a world where bandwidth is cheap and hard drives are huge, even if statically linked exe's are a bit bigger, I'm willing to pay that price to ensure that my users always get to run the code I ship, rather than some other code that happens to be on their machines.
If used consistently the SxS stuff could have created a world where users could have multiple copies of common DLLs and we wouldn't have to worry about shipping private copies, but in the real world dynamic linking means that users wind up with dozens of copies of common DLLs sitting in different directories, just in case someone else steps on the copies in the standard path with new versions that they haven't tested against.
Dynamic linking is an example of pre-mature optimization, and as such should be avoided unless there is a compelling quantitative reason for using it, and only then for non-critical systems, where the undefined behaviour that may result when new versions of libs are installed in the standard path doesn't matter.
Remember: if you are installing private copies of common DLLs or using SxS to allow multiple public copies of common DLLs to cohabit nicely, you should be statically linking your code. Otherwise you installer is bigger than it needs to be because it contains whole DLLs are part of the redist package, rather than just the bits you need compiled into your app.
hose centrifuges are not easy to make (they spin up to 90,000 RPM) and something as a fingerprint on one of them will make it shatter when it's spinning that fast.
Gas centrifuge technology, which has been available since the '80's, gets around most of this problem. It was predicted at the time that it would be hugely proliferating because it would make uranium enrichment relatively cheap and easy. Iran's programme is just proof of this.
As other posters here have pointed out, making a uranium bomb is incredibly easy. Little Boy was detonated operationally without the design ever being tested. Fat Man was a plutonium implosion design, and it the Trinity test was run to ensure it would actually work.
Also, remember that plutonium implosion was tricky because of the exact timing requirements... in 1945. The trigger switches used involved TUBES of one kind or another. In these days of high-speed solid state electronics, where off-the-shelf chips with 1 ns switching times can be bought for a few dollars and drive a few cm of transmission line with ease, the problem of plutonium implosion is vastly easier to solve.
Making a big deal out of some people in Iran knowing how to build a nuclear bomb is silly, and plays in ignorant stereotypes of how difficult it is to actually do the job. Canada has the knowledge to build a nuclear bomb too, and has for decades. We'll only build one if we decide the nation of idiots to the south of us has gone completely off the rails, and starts trying to overthrow our democratically elected government, as it did in Iran back in the '50's. On that basis, if I were an Iranian, I'd bloody well want my country to have the Bomb.
On the other hand, Canada also has a large peaceful nuclear programme, despite sitting on a whole lot of oil. So anyone who suggests that Iran doesn't want a peaceful nuclear programme just because they have oil is clearly an anti-empirical idiot.
I'm not aware of any version control system that does this. Is anyone else?
Huh? You're not aware of any version control systems at all? Strictly speaking it is the particular diff tool rather than the VCS that matters in this case, but every diff tool I've ever worked with has options specific to suppressing exactly the kind of trivial differences you've inexplicably cited as a "big problem."
Translating these results into some meaningful treatment for normal adults is highly likely to face a lot of roadblocks and complexities.
I generally agree with this, but there are two things that raise this above the usual "cures cancer in mice" hype.
The first is that these are xenografts, which means they're dealing with authentic human cancers, which are in general far tougher to kill than cancers in other species (we are tuned up for great longevity for obvious evolutionary reasons, and therefore incredibly cancer resistant compared to most species, meaning the few human cancers that do become malignant are incredibly hard to kill.) A quick look at the paper shows they've used multiple cell lines for the xenographs, which is also good.
The second is that there is already evidence of reduced cancer rates in humans taking this stuff (pancreatic cancer only, and diabetics only, so limited but suggestive data.)
The full paper is available at:
http://cancerres.aacrjournals.org/cgi/reprint/69/19/7507
and it really is one of the few on the topic that I'd honestly say has results that can fairly be characterized as "dramatic".
You're right: they may lead to another dead end. We've seen a lot of those before. But this looks like solid research and very promising results. Clinical trials on humans are in the works, with patient enrollment starting perhaps as soon as next year.
3. Your last sentence makes no sense whatsoever.
And his first sentence is a a lie. Anyone intelligent enough to form a sentence is capable of reasoning out the answers to the "questions" he is asking. That he deliberately injects those questions (whatever they are--I didn't actually open his comment, only the replies to it) into this forum is evidence that he has an aggressive ideological malignancy.
We need congressional elections similar to the EU parliament elections where parties get membership based on the % of votes or a smaller federal government.
Why do you want to give private organizations a given fraction of parliament? Parliament should represent people, not parties, and anyone who tells you that their MP is too incompetent to represent their constituents is telling you their MP needs to be replaced. Representational democracy has worked for centuries without anything like the level of partisan capture that exists today, so claims that there are unsolvable problems with it just reflect the ignorance or malicious intent of the person making the argument.
The world needs less partisan representation, and electoral reform won't get off the ground until the people pushing it realize that the only effective reform will be one that reduces partisan power, not increases it by embedding the existence of parties in the electoral process. I realize that the parties are already deeply embedded in the electoral process in the US, which is one of the main reasons why the American electoral system is so much more broken than virtually anywhere else in the world.
Electoral reforms have been raised in several Canadian provinces in recent years, and while none of them have passed the proposals in British Columbia, which were less partisan, came a lot closer than the insanely partisan system Ontario voters were presented with.
n fact, would this imply that there is a large scale migration of rock from the sunward side of the planet to that opposed to the sun (and would this in turn alter the fundamental planet shape? I envisage dinnerplate planets...)
I briefly entertained the same fantasy--I even wondered if this could destablize the tidal locking by transporting mass from the point closest to the sun to more distant points, which on reflection seems highly unlikely.
It is possible that the processes described in the article result in a bit of a flat spot close to the star and a mountainous bulge of scree along the terminator, but with lava to transport molten rock across the surface, and rock being pretty plastic at such high temperatures anyway, it is unlikely that anything so extreme as a dinner-plate shape could take form, which is a damned shame.
Why should the station be charging the batteries?
Because people desperately need to look clever by insisting that their own idiotic ideas about the right way to use a technology is the only conceivable way.
Many of the apps we used (hello, Oracle Colaboration suite, looking at you) require really messing with system files to make work decent. This makes other programs very unhappy, so apps like these really need to run on their own box.
This makes sense now: incompetent server developers are the driver behind this aspect of VMs. Other aspects are independent of this, but a lot of people responding here have simply taken for granted that most servers are written by monkeys, and are therefore unable to play nicely with others.
I kind of figured this was the case, having written server code (back in the '90's) and seen the gyrations my team went through to make sure we were able to run without requiring a stepped-on environment, but I found it hard to believe that badly-written server code had become so common as to make virtualization the only viable solution.