In particular, in the case of logging and other destruction of the environment, many activists have long since given up on increasing public awareness in time to protect the forests from destruction, and have resorted to direct action to try to stop the activity from happening, and I think in many cases this is morally correct.
I don't agree with this. The activists have put their personal opinions about the harmfulness of the logging above everyone else's - it's arrogance, not "morally correct".
It's hypocritical to take the benefits of a democratic society - being able to have your voice heard - and not taking any of the responsibility - having to abide by the rule of the majority. A person who does so may be doing something for a morally correct "greater goal" in their eyes, but they are sacrificing another morally correct "greater goal" - which is equality of all people. In that case, it's tough to claim that their morals are "higher" or "more correct" than other people's (i.e. their belief that destroying the forests is wrong) because they're willing to sacrifice other morals when they become inconvenient.
(In truth, said activists actually can do more harm to their goal than good, because it will lower public perception.)
Hence its name - it was named after the Sun, where its absorption lines were found, unlike anything known on Earth at the time.
Helium's lifetime in the atmosphere is distinctly finite (thousands of years) and so the atmosphere has virtually no helium in it whatsoever.
Almost all the helium known to the world is located in gas pockets above oil fields, generated by alpha decay of radioactive elements. The US has some of the largest amounts of helium, though the rest of the world has quite a bit. One distinct point is that the amount of helium in the world is distinctly finite - much more so than oil or coal. At our present rate of consumption it's very unlikely that without conservation measures significant amounts of helium will be available as soon as the late 21st century. Yah, bizarre as it sounds, helium is what we should be trying to conserve much more so than oil, natural gas, or coal.
It's worse than that - I can't see how HF could possibly produce the huge variety of chemicals that water can. Water's a covalent dipole, but HF in its liquid state would just be a bunch of fluorine and hydrogen atoms in near proximity to each other. They wouldn't be able to form bonds *between* things because the atoms are free. Water, in contrast, can bond things together with hydrogen bonds.
Life needs complexity, so it needs something that can create combinations. For that, it needs a covalent dipole, and the two easiest ones are ammonia and water. Maybe ammonia would work, but I'm betting that the reason we're water-based life isn't due to some freak chance of the location of our planet. (Keep in mind that were it not for life-related factors, water would, in fact, *not be* liquid on this planet. The blackbody temperature of this planet is below freezing.)
I have been planning on voting for Kerry, preciesely because he is the "lesser of two evils". I suppose I shouldn't do that now. Either way, I'll regret it. ***Sigh***
Trust me, I know the feeling. The problem is that I know that the rest of the US still votes as "the lesser of two evils", so there's no real chance for a third-party candidate to succeed. It's terrible to talk as if you are throwing your vote away, but given the current environment, that's kindof what's going on.
Mmmm.... well, to be precise, you are allowed to protest against the current government in a legal manner without being arrested.
That's the point, plus the fact that the "legal manner" is very, very broad, which means that it is practical to protest in a legal manner. There are plenty of countries (and/or times) where this wasn't feasible.
In my view, protesting by illegal (but still moral) means is also fine, and people should be arrested for it as part of the proper use of the technique.
If there is a way to protest that is as or more effective than legal means, then a way should be found to make it legal. The entire point of this country is that there should be no need to protest illegally. That's the idea - we're supposed to have evolved past the Boston Tea Party.
However, we do need to have some authority to prevent abuses of that freedom, which is why certain forms of protesting are not allowed - but those forms should be illegal only if they can be effectively replaced by legal means.
Keep in mind that the desired outcome of protesting is increased public awareness, not cessation of the activity being protested. This is supposed to be a democracy, which means the will of the majority rules. Half the problem with protesters is they constantly forget that their goal is not to stop the activity. That's not their right, nor their choice to make - it's the legislature's choice to make. Their goal is to influence the people, who influence the legislature.
Murdering a public official, while it may gain you a lot of publicity, is not the only way to gain publicity for a cause, and therefore is not an appropriate method for protesting.
Getting arrested either means 1) the law in the country is too strict, and violates our founding ideals (which is true, for many laws!), and what you were doing *should have* been legal, or 2) you were overstepping your bounds, and protesting in a way that is inappropriate.
I can't imagine a situation where illegal protesting would be considered "okay" to me, unless the law is screwed up. Sit-ins or picketing which impedes a person's ability to perform a legal activity or illegally damages property is just wrong.
Honestly, it's about not being a dick. If I don't agree with someone else's actions, I want to be allowed to say "I don't agree." Loudly. Constantly. Over and over if I want to. But if what they're doing is legal, then I should not stop them, because I could be wrong, according to the will of the people. If the situation were reversed, I would be outraged if someone was preventing me from doing something legal, simply because they didn't agree with it. It is not an individual's right to make the law!
(In this current case, it's not the law that's screwed up - it clearly defends the guy who was doing it - but the law enforcement agency. They should be sued.)
and then you have a faster than light link to mars *after* it's been estabished by the standard travel of actually getting the entangled particle to the remote location)
Would that work?
Could you do what you said - move an entangled pair of 'pennies' from Earth to Mars?
Yes.
Would that be useful?
Not tremendously.
Just because two things are entanged doesn't mean you can communicate with them. In fact, you can't communicate with them at all.
Imagine it like this:
Suppose you have two cities, on either side of the Moon. Now suppose you have someone on Earth that shines a laser at City A, on one side of the Moon. Now the person on Earth moves the laser as fast as he can (let's say 1 nanosecond) to point from City A to City B.
The "point of light" on the surface of the Moon will move from City A to City B in 1 ns. The speed of that "point of light" is "((radius of the moon times pi) divided by (1 nanosecond)) divided by the speed of light = 18 206 605.7" via Google. That's 18 million times the speed of light (probably around warp 7 or so:) ). No funky entanglement, no nothing. But it's useless, because no information is going from City A to City B, only from Earth to City A, and then Earth to City B, and both of those trips take the speed of light. Neither City A, nor City B, can influence the spot of light at all, therefore there's no information transfer.
In the entangled penny example, Penny A could be at City A, Penny B could be at City B, entangled. But again, while City A and City B can affect the pennies, they can't affect the other penny in a detectable way. While they can 'collapse' Penny B's entangled state, you cannot detect uncollapsed states, so to them, nothing detectable happened. All that happens is that at the end of the day, City A and City B can look at their experimental results, and for every result City A gets, City B will get a result that corresponds to that result. But the individual results from City A and City B are random, just like the movement of that point of light.
It's exactly the same as a quantum shadow. City A and City B could communicate and be amazed that their two experiments agree perfectly, but neither of them can affect the outcome of the experiments. The only difference between the "point of light" and "entangled penny" bits is that in the point of light case, an observer on Earth was causing the changes, and in the entangled penny case, the Universe was causing the changes.
What's the point of civil disobedience if you don't get arrested for it? The whole idea is to get arrested to get publicity for your message and to put a stress on the system.
Because in this country, you are allowed to protest the current government without fear of being arrested. At least, you're supposed to be able to.
Yeah, I've notice that too. Any time you don't agree with some liberal person you'll ostracized as "stupid" or a "sheep".
First they came for the Democrats, and I did not complain because I was not a Democrat.
You should know the rest.
Give me a break. This is freedom of speech we're talking about here. And freedom of speech isn't about being able to write a nice, polite opinion piece that's "slightly" against the government stance. They could do that even in the worst times in the USSR. Freedom of speech is about protecting the worst kind of speech - the kind that is flagrantly opposed to the government order, Michael Moore type stuff. Freedom of speech should be restricted only very carefully - "clear and present danger" and all that. It's not "clear and present annoyance". Part of the cost of living in a free society is putting up with people who don't share your views.
If you can only protest "politely", it isn't America anymore. All activists have a right to have their case heard, because one of these years, people like them are going to be right.
You're really fixated on this Hitler stuff. When was the last time any liberal mentioned "Hitler" and "Bush" in the same sentence? And I'd like a link please, otherwise you're just trolling.
That wasn't the point. Read the two again.
The point was that the great-grandparent's argument for supporting Bush is crazy. You could've used it to support Hitler at the time (ignore what we know now - obviously few would've supported him had they known). His argument essentially is "yes, he's a jerk, he states things that are very dangerous to our fundamental way of life, and he lies to us... but I'm going to vote for him because I hate the fact that other people are making him out to be a demon, when he's not."
If you agree with someone's opinions, but not their tactics, you don't go out and do the exact opposite just to spite them. That's stupid. You should never, ever let your vote be influenced by anything other than the candidate and what they stand for. If you don't like the candidate, and don't want them in office, don't vote for them. Voting for someone because you don't like the opposition ("lesser of two evils") is crazy - especially if you don't actually like the candidate you're voting for.
But what do I know, that's just the whole "democracy" thing.
While the last really is a benefit java posesses the other two aren't that relevant.
True. The grandparent post, however, was saying that an interpreted language must be slower than native code. This was the point I was trying to show was wrong - Java isn't the "prime example" of interpreted code, in my opinion. I actually think the Transmeta processors are much better examples, and I think we would all realize this if Transmeta had the money to make a true performance processor.
If you realize that interpreted code, emulation, and whatever you want to call the "RISC-in-CISC" design of modern processors are all the same thing, then the statement I was making - that those can be faster than native code.
It all comes back to the halting problem, and Wikipedia has a great point here: imagine the following algorithm -
int main(void)
{
BigInt i, j, k;/* assume arbitrary-precision integers */
for(i=j=k=1;--j||k;k=j?i%j?k:k-j:(j=i+=2));
return 0;
}
which looks for an odd perfect number, none of which are known to exist, but math has no idea whether or not they fundamentally do exist.
So there's no way the compiler can figure out that the comparison to stop the for loop may never come, but an interpreted language can notice that the likelihood of this branch ever being taken is virtually zero. There's in fact probably a formula for when the JIT compiler should start saying 'this branch will never happen - and if it does, the performance gains that come from assuming that it never happens will outweight the penalty for when it does'. Ballparking it, I can't imagine that it would take more than a hundred loops or so.
This is a bit of a poor example for an interpreted language, because there's not really any optimization that can be done here except branch prediction always assuming that the branch is not taken - although the JIT compiler could add the 'hint' to the hardware branch predictor of 'just ignore this branch' after it becomes obvious that the branch is never taken.
But you can imagine situations where an interpreted language could excel, especially given the relative "plateaus" of performance that modern PC's have:
registers>>L1-cache>>L2-cache>>main-memory>>hard -d rive
If an interpreted language can shift a program from main-memory bound to L2-cache bound, it can improve the performance massively.
In particular Java is going to be slow because most JIT or interpreters I know of don't seem to remember things from one instance to the next
Which baffled me, especially considering that, for instance, the Sun JVM on Windows stays resident after loading for the first time. Completely bizarre. Apparently the Sun JVM is very good at optimizing for lots of branches and jumps, though - hence the reason that the simple "nested loops" example that I linked to performed so well in Java, even compared to the Intel compiler.
In essence, the interpreter should at the very *least* act like a gigantic BHT (branch history table) for the processor, and expect code segments to act exactly the same the next time they're run, or at least identify segments that run identically, and feed the processor "very-likely/very-not-likely" hints. Given the performance penalty for branch mispredicts, this could have a serious performance boost, especially on long-pipeline processors like the P4.
There is *no* way that a interpreted or JIT compiled language can be *faster* than native code.
Nope.
There are actually quite a few ways that an interpreted language can be faster than native code.
If you were right, then VLIW processors would've taken over long, long ago.
It's important to realize that the instruction set that any processor uses is not its native instruction set, for a long time now. Ever since the Pentium days, there's a "instruction decode" step in the pipeline, and even PPCs use it to pare down the (comparatively simpler) PPC instruction set to something more RISC-like.
So what does this have to do with programming languages, you might ask?
The point is that the analogy is exactly the same: VLIW processors rely on the instruction stream being very parallel, and well tuned to the architecture so that they can be very simple and very fast. There's only one problem - compilers can't be that smart. You don't have all the information until the program runs - this is very similar to the Halting problem. Until the program runs, you don't know how it will behave.
So what you're saying is "I don't see how an interpreted language can be faster than native code", likely because of the overhead. The answer to your "how" is that the interpreter - like any modern x86 computer - has more information available to it while its running than the compiler had when the program was compiled. Therefore the possibility exists that an interpreted language can outperform native code, because it can optimize for cases that the native code cannot. If that optimization is enough of an improvement over the overhead, you win.
It is for this reason that modern x86 computers perform so well compared to VLIW architectures - it's very difficult to extract parallelism from the code itself, before it's executed. It's actually more efficient to extract the parallelism while the code is actually running.
This is the exact same reason why Java can beat C++, in certain cases. And for benchmarks, http://cpp.student.utwente.nl/benchmark/. Note that this is in fact someone improving upon a C++ vs Java benchmark that showed Java won, so this is C++ striving as hard as it can.
Here you can see that for certain cases, Java can win. The most notable one is the nested-loop benchmark, where the Intel C++ compiler ran in 1.8 seconds, and the Java example ran at 1.05 seconds.
Your next statement might be that "yes, but in assembly..." and I will then say that yes, I highly doubt that you can find a Java program that will beat a hand-assembled piece of code. But it still is *possible*, because the interpreter may be able to perform some optimization during runtime that the person doing the coding can't because it's not strictly correct - this is akin to a branch predictor in hardware. It's allowed to cheat so long as it's later proved that it was right, but then pay a penalty when it's wrong.
Just like every other license, you have to have ownership before you can license it out. The GPL is no exception. You have to assign ownership to the FSF so that they can enforce the license.
Uh... what the hell are you talking about?
The only reason you would sign over copyright ownership to the FSF is if you wanted them to defend it in court because you aren't capable or willing to do it.
If you want to defend it in court, feel free. The FSF will be happy to help with any points relating to the GPL, of course.
Now that may be fine for someone else, but I'd never assign ownership of something I did to Stallman.
Neither did IBM. Hence the reason that they're suing for copyright infringement due to violation of the GPL for software they wrote, and which they hold the copyright on.
I think you're very, very misunderstood about what's needed to place a body of work under the GPL. You absolutely don't need to sign over copyright to the FSF. The FSF just recommends it for developers because most developers don't have the legal resources that the FSF has.
The GPL is designed to build up the body of free software to the level of pay software
No, it's not. The GPL is designed to ensure that when you place a body of work in the realm of free software, that it won't leave that realm of free software. That's all.
This is actually better for companies than the LGPL, because they are guaranteed that while they will get the support of the open source community, no competitor will be able to use that software, change it slightly, and release it again, without those changes being available to the company as well. So there's no risk associated with releasing the source code, other than opening the source code itself. With the BSD license there's a definite risk for businesses.
I think the BSD license is more appropriate for individual developers who are just coding for fun, actually.
Yes it is. That's what gender means. Gender has nothing to do with sex except that words describing females (the sex) are generally female (the gender) and similarly for males.
Well, no - if you go look up gender, you get
1. Grammar.
1. A grammatical category used in the classification of nouns, pronouns, adjectives, and, in some languages, verbs that may be arbitrary or based on characteristics such as sex or animacy and that determines agreement with or selection of modifiers, referents, or grammatical forms.
2. One category of such a set.
3. The classification of a word or grammatical form in such a category.
4. The distinguishing form or forms used.
2. Sexual identity, especially in relation to society or culture.
3.
1. The condition of being female or male; sex.
2. Females or males considered as a group: expressions used by one gender.
You'll note that definition 1 is what you're saying - that's the grammatical definition. But definition 2 and 3 are what I was talking about - a table, to French speakers, is not "female". It's just "la table".
So we're both right, though maybe I should've said "medical gender" rather than "grammatical gender". Again, half the problem is that people mix the definitions of gender, and assume that since the French/Spanish/etc. language have a concept akin to definition 1, that that same concept must be definition 2,3 as well, and that's just poor teaching of the language.
Not a bad post, but this example doesn't work. There actually is a rule in English for when to use "more" and "most", and when to use "-er" and "-est"
There are rules for which words take female modifiers, and which words take male modifiers in Spanish, too. And just like in English, there are a few exceptions, as well.
That doesn't change the point of the example. The point is that Spanish speakers/French speakers don't attribute a "gender" to things just because the language makes it look like they do. It's just a curiousity of the language.
Is a table male or female? It's an IT to me, and that's the way it will stay.
It's an "it" to the French, too. It's not that the table 'has' gender - it's that the word belongs to a certain class of words that behave like it - that is, they're preceded by "la", "une", etc. In French, it's not "table", it's "la table" - the article is linked to the word itself (much like in English the infinitive is two words, but one idea).
In truth, it has nothing to do with the object itself. The French don't know why it's "la table" and not "le table", other than to tell you that it doesn't sound right as "le table".
The problem really comes because teachers like to teach it as if it really is confusing, and massively different from English, so you have to start seeing the gender in things. That's crazy. It's not different. It's just something you have to memorize, just like they have to memorize which adjectives you use "more", "most" with, and not "-er", "-est".
In truth, you can see the obvious bias in the study, as well. If your society has no language for counting above "two", then it likely has no need for counting above two, and so when presented with a situation where they need to count above two, they will be confused, because it's something they haven't done before. After all, when you're taught numbers, you're taught to count! So is it linguistic? I doubt it. I think the reverse is more true - thought (and society) shapes language.
I'd have to find out more about the study, but it seems really weak. You'd need a very careful control - that is, someone who lived in the same society as the Piraha, but spoke a different language that contained numbers higher than 2, and even that would be touchy because, as I said before, learning numbers above 2 means you were taught to count. But anyway, obviously no one like that exists, and I find it ludicrous that the psychologist made the leap "language directs thought" rather than "society directs language".
--SCO then claims to own Linux, since they now consider it to be a work derived from AIX, which they claim to own.
SCO's not claiming that anywhere. If they did that, they'd be laughed out of the courtroom, and then probably promptly sued by quite a few people. They can't usurp Linux developer's copyrights just because IBM did something. Linus and the other kernel developers still retain possession of the code they wrote.
SCO is only claiming that they have the rights to the code that IBM inserted into AIX and then transplanted into Linux. Maybe SCO believes what you're saying - if so, thank God, because there's not an intelligent lawyer on their entire staff. But their entire legal defense so far has never once tried to claim ownership of Linux. They can't.
Why SCO continued to distribute the Linux kernel, I have no idea. Why they tried to charge licenses for Linux, I have no idea. It was clearly illegal by the terms of the GPL, and as IBM is pointing out, SCO can't distribute anything without the GPL.
IBM is actually doing what several people on Slashdot suggested to several kernel developers: since SCO is distributing the Linux kernel in violation of the GPL, they are violating copyright, and can therefore be sued by the copyright holders, namely IBM. So IBM is suing to dismiss a claim, and to injoin SCO from distributing Linux. I honestly can't see how the judge will disagree. It's very clear cut copyright law. If the GPL is valid, they can't tack a more restrictive license onto it (which they did). If it's not valid, they couldn't distribute the code at all (which they did).
If SCO tries to claim ownership of Linux as a derivative work of AIX to defend itself, I'm sure the conversation will essentially be
SCO: So you see, your Honor, our distribution of Linux is justified by the fact that as a derivative work of AIX, we are the copyright holder of Linux, and... Judge: Wait, you're claiming that you hold the copyright over all the Linux code? Including the code that was written by people who had never heard of IBM? SCO: Um... Judge: Do you have transfer of copyright paperwork from the people involved? Linus Torvalds, for example? SCO: Um... Judge: Get out of here.
Since SCO claims full ownership of all the code in Linux
Really, honestly, they're not doing that. They've never claimed that in a court of law, and they never will. If they were, you wouldn't see Boies handling the case, anyway. You can't "usurp" copyrights from people, especially people you've never signed a contract with. There are 431 listed authors in the CREDITS list, and I'm sure none of them have transferred copyright to SCO. Thus, either the Linux kernel is completely undistributable (if it has SCO's IP in it) or it's distributable under the GPL. Either way, SCO couldn't distribute it the way they did.
I have no idea how SCO is going to respond to that motion. I don't know how they can, other than to feign ignorance about the distribution. If they try to claim that the GPL is invalid, and the code is in the public domain, IBM (and the judge - you can't "accidentally" give up copyright - SCO has actually said this themselves!) will rip them a new one. If they try to claim that they didn't know they were doing it, it'll shred their credibility in court. They were doing it up until August of this year! If that's true, the judge won't believe a word their executives say, because clearly they don't even know what their own company is doing. If they try to claim they hold the copyright to the code in Linux, see above. I'm really curious what they're going to say. It's damn funny.
SCO's argument is that code IBM added to AIX belongs to SCO, and that any derived work also belongs to SCO.
You're missing the grandparent's point: IBM has contributed code that has nothing to do with AIX, and would never work on AIX in any case, like the MWAVE driver or countless Thinkpad patches and drivers.
Unless SCO manages to convince the court that every single piece of code that IBM has written ever, there is no way that this summary judgement can't be granted.
just including JFS code in Linux gives SCO all rights to all parts of the kernel
Even if SCO's claim that by including the JFS code in AIX it becomes subject to the restrictions of the AIX license were true, this still won't give them any rights over the Linux kernel, which is protected by its own license.
The GPL is actually quite clear about this point - if the code is covered by a license that's mutually incompatible with the GPL, then you can't distribute it at all. So SCO is breaching IBM's copyright on all of the other code in Linux that has nothing to do with AIX, even if their bullshit claims about owning JFS code were true.
Basically it's similar to IBM's previous motion for judgement (which was: "Your Honor, we didn't do it. Even if we did, we have affadavits saying that we could've, and we have interviews saying that we could've, and we have this legal document from the real copyright holder saying we could've. But we didn't.") - it's "Your Honor, they're violating our copyright. Even if they own our code from AIX, which they don't, they're violating our copyright on many other pieces of code. And even if they're right that the GPL is invalid - which they aren't - they'd *still* be violating our copyright by distributing our code without a license."
No, ion drives do not have enough thrust to achieve escape velocity (25'000 mph for Earth).
They don't have enough thrust to reach escape velocity for Earth, and that's because there's this nasty blanket of stuff around us called the atmosphere.
There are mechanisms which generate far less thrust than an ion drive (the Yarkovsky effect: the differential light pressure between radiated photons and incoming photons due to rotation) and still push something to escape velocity. It won't work on Earth because static friction and air resistance reduce the net thrust to zero.
I don't think that's correct. One could easily imagine a parabolic path on which some solar sailboat is on, and reducing that velocity to below escape.
Depends which direction you're heading when you're at escape velocity. You can't slow radial velocity no matter what: if your radial component (outward) exceeds escape velocity, no solar sail could ever stop you: you're heading out of the system.
Any other direction, it's possible, however, it is actually harder: you can't reduce your tangential speed without increasing your radial speed slightly (because if the sail is edge on, there's no surface area) so there's actually a range of directions, centered on radially outward, where if you exceed solar escape velocity along any of those directions, you're leaving the neighborhood.
How? The flight path is always away from the Sun when you're on your way to pluto.
No solar sail could ever fully oppose the Sun's gravity unless it was, I dunno, half the size of Jupiter's orbit or something. OK, maybe not that large. But it'd be huge.
All you're doing is adding to your orbital speed by tilting the sail to accelerate along that direction. So you slowly spiral outwards.
To return, you just do the opposite: slow your rotation, and you spiral inward. You'll have to be careful to alter orbit at several points to circularize it (so you're not going at an insane speed when you hit the inner solar system), but it can be done.
In space, there is no "water" for a rudder to work in
Actually, there kindof is : because all motion around the Sun is necessarily rotational (especially if you launch from Earth!), your tangential velocity is essentially your "water" - to fall inward, you angle the sail so that it slows you down, rotationally.
You could always cut the sail and let the Sun's gravity slow you...
Things going around the Sun are in orbit. There's no possible way that a solar sail could fully oppose gravity unless it were gigantic. Actually, that's not such a bad undergrad physics problem... anyway. The Sun's gravity wouldn't slow you down - it keeps you in orbit. You actually use the sail to slow you down, and then your slower orbital speed lets you fall in.
Which ones do you use? Now which ones does Joe Sixpack use? On a desktop, at home?
For a machine that browses the Web, what services do you need? Considering many people use the stock NATing routers as internet sharing devices, apparently most people don't need any network services. So long as they can get an outbound connection, the inbound ones don't seem to matter much.
For those that do, they should learn the dangers of the software that they're installing.
and use Lynx to browse the web...
Mozilla would be fine. Most of its recent security issues were Windows-only problems. And they were very minor, comparatively.
Solar sails can tack, because slowing your orbital velocity moves you closer to the Sun. If you put the sail at an angle such that majority of the light pressure opposes your direction of motion, you will move inward.
So to slow down, you just alter the angle of the sail. Easy enough.
No, the slowest part of PC's today is the user interface. The rate at which a user enters data (via keyboard/mouse) is a fraction of the rate at which a user thinks. (Your mileage may vary, of course.)
You're wrong.
$ mozilla &
7 characters * (1/500 cps) = 14 ms
That's 80 or so wpm, so maybe that's a bit fast. But still, 14 ms is on par with just the seek time of a hard drive, and that's not even considering the transfer. Plus I don't know *any* computer that can load Mozilla, uncached, in under 14 ms!
This is a computer, after all. One click could start a massive simulation, or switch between two programs that are each using 100M of memory, one of which is sitting in swap. Or it could open a 600M video file. Or it could type the letter "c" in a Word document, in which case you'd be correct. But that's not everything.
Applications today fall into one of four categories:
frequency limited: small programs that fit entirely within registers/L1/L2 cache, all of which scale with clock speed.
memory bandwidth limited: larger programs that run entirely in memory, and thrash the cache regularly
disk limited: programs that thrash the disk cache excessively, and are thus I/O limited. Network limited is about at the same speed
user limited: programs that primarily wait on user input.
It'd be nice to believe that everything's sitting in the last category, but that's simply not true. Complicated simulations will sit in category 1 (along with Quake 3 at low resolutions, apparently). Media encoding will sit in category 2. Application launches sit in category 3. And most Office programs sit in category 4. The differences in speed between these categories are orders of magnitude.
Category 1 increases regularly, by Moore's Whatever. Category 2 increases regularly due to industry improvements in memory design - still slower than category 1. Category 3 increases basically only due to rotational speed increases, and those are bounded by obvious laws of physics. I can't have a 500,000 rpm disk drive and expect to be able to read it easily. It's nice to see someone try to push Category 3 up to the same speed as Category 2.
I don't buy it, however, mainly because if you look at the transfer rates quoted, there's a huge variation: sustained R/W bandwidth: 14-110 MB/s? Who wants to bet that the "W" bandwidth is 14 MB/s, and the "R" bandwidth is 110 MB/s? Flash is notoriously slow at writing, and very fast at reading. Disks are quick at doing either.
Actually, I had a Red Hat 5.2 box installed in 1999 unfirewalled until just recently. It's never been rooted once, and I haven't installed an update on it for multiple years, other than to fix a bug in an app or two. It's not running any more, so don't bother with the "oh yah? well it will be now!" jokes. And yes, I do know that it wasn't rooted. I did check pretty carefully periodically, and the network admins were pretty careful about watching for suspicious traffic.
Why was it okay? That's simple enough - there were no vulnerable services running on it.
That particular machine was a very limited server - it didn't even respond to machines outside of the local subnet, but the argument applies even better to desktops. What server does a desktop *need* running? None.
This is the point - Linux can get rooted from servers, which you can avoid totally if you don't need the server. But Windows can be rooted from IE, or in the case of XP, through a service that's installed by default (that you pretty much *can't* disable before the installation's complete, so the machine would be rooted already). In other words, you can get rooted for just using Windows as a desktop. It's a bit harder with Linux.
Slashdot Mirror
In particular, in the case of logging and other destruction of the environment, many activists have long since given up on increasing public awareness in time to protect the forests from destruction, and have resorted to direct action to try to stop the activity from happening, and I think in many cases this is morally correct.
I don't agree with this. The activists have put their personal opinions about the harmfulness of the logging above everyone else's - it's arrogance, not "morally correct".
It's hypocritical to take the benefits of a democratic society - being able to have your voice heard - and not taking any of the responsibility - having to abide by the rule of the majority. A person who does so may be doing something for a morally correct "greater goal" in their eyes, but they are sacrificing another morally correct "greater goal" - which is equality of all people. In that case, it's tough to claim that their morals are "higher" or "more correct" than other people's (i.e. their belief that destroying the forests is wrong) because they're willing to sacrifice other morals when they become inconvenient.
(In truth, said activists actually can do more harm to their goal than good, because it will lower public perception.)
There is no helium in the atmosphere.
Hence its name - it was named after the Sun, where its absorption lines were found, unlike anything known on Earth at the time.
Helium's lifetime in the atmosphere is distinctly finite (thousands of years) and so the atmosphere has virtually no helium in it whatsoever.
Almost all the helium known to the world is located in gas pockets above oil fields, generated by alpha decay of radioactive elements. The US has some of the largest amounts of helium, though the rest of the world has quite a bit. One distinct point is that the amount of helium in the world is distinctly finite - much more so than oil or coal. At our present rate of consumption it's very unlikely that without conservation measures significant amounts of helium will be available as soon as the late 21st century. Yah, bizarre as it sounds, helium is what we should be trying to conserve much more so than oil, natural gas, or coal.
It's worse than that - I can't see how HF could possibly produce the huge variety of chemicals that water can. Water's a covalent dipole, but HF in its liquid state would just be a bunch of fluorine and hydrogen atoms in near proximity to each other. They wouldn't be able to form bonds *between* things because the atoms are free. Water, in contrast, can bond things together with hydrogen bonds.
Life needs complexity, so it needs something that can create combinations. For that, it needs a covalent dipole, and the two easiest ones are ammonia and water. Maybe ammonia would work, but I'm betting that the reason we're water-based life isn't due to some freak chance of the location of our planet. (Keep in mind that were it not for life-related factors, water would, in fact, *not be* liquid on this planet. The blackbody temperature of this planet is below freezing.)
I have been planning on voting for Kerry, preciesely because he is the "lesser of two evils". I suppose I shouldn't do that now. Either way, I'll regret it. ***Sigh***
Trust me, I know the feeling. The problem is that I know that the rest of the US still votes as "the lesser of two evils", so there's no real chance for a third-party candidate to succeed. It's terrible to talk as if you are throwing your vote away, but given the current environment, that's kindof what's going on.
Mmmm.... well, to be precise, you are allowed to protest against the current government in a legal manner without being arrested.
That's the point, plus the fact that the "legal manner" is very, very broad, which means that it is practical to protest in a legal manner. There are plenty of countries (and/or times) where this wasn't feasible.
In my view, protesting by illegal (but still moral) means is also fine, and people should be arrested for it as part of the proper use of the technique.
If there is a way to protest that is as or more effective than legal means, then a way should be found to make it legal. The entire point of this country is that there should be no need to protest illegally. That's the idea - we're supposed to have evolved past the Boston Tea Party.
However, we do need to have some authority to prevent abuses of that freedom, which is why certain forms of protesting are not allowed - but those forms should be illegal only if they can be effectively replaced by legal means.
Keep in mind that the desired outcome of protesting is increased public awareness, not cessation of the activity being protested. This is supposed to be a democracy, which means the will of the majority rules. Half the problem with protesters is they constantly forget that their goal is not to stop the activity. That's not their right, nor their choice to make - it's the legislature's choice to make. Their goal is to influence the people, who influence the legislature.
Murdering a public official, while it may gain you a lot of publicity, is not the only way to gain publicity for a cause, and therefore is not an appropriate method for protesting.
Getting arrested either means 1) the law in the country is too strict, and violates our founding ideals (which is true, for many laws!), and what you were doing *should have* been legal, or 2) you were overstepping your bounds, and protesting in a way that is inappropriate.
I can't imagine a situation where illegal protesting would be considered "okay" to me, unless the law is screwed up. Sit-ins or picketing which impedes a person's ability to perform a legal activity or illegally damages property is just wrong.
Honestly, it's about not being a dick. If I don't agree with someone else's actions, I want to be allowed to say "I don't agree." Loudly. Constantly. Over and over if I want to. But if what they're doing is legal, then I should not stop them, because I could be wrong, according to the will of the people. If the situation were reversed, I would be outraged if someone was preventing me from doing something legal, simply because they didn't agree with it. It is not an individual's right to make the law!
(In this current case, it's not the law that's screwed up - it clearly defends the guy who was doing it - but the law enforcement agency. They should be sued.)
and then you have a faster than light link to mars *after* it's been estabished by the standard travel of actually getting the entangled particle to the remote location)
:) ). No funky entanglement, no nothing. But it's useless, because no information is going from City A to City B, only from Earth to City A, and then Earth to City B, and both of those trips take the speed of light. Neither City A, nor City B, can influence the spot of light at all, therefore there's no information transfer.
Would that work?
Could you do what you said - move an entangled pair of 'pennies' from Earth to Mars?
Yes.
Would that be useful?
Not tremendously.
Just because two things are entanged doesn't mean you can communicate with them. In fact, you can't communicate with them at all.
Imagine it like this:
Suppose you have two cities, on either side of the Moon. Now suppose you have someone on Earth that shines a laser at City A, on one side of the Moon. Now the person on Earth moves the laser as fast as he can (let's say 1 nanosecond) to point from City A to City B.
The "point of light" on the surface of the Moon will move from City A to City B in 1 ns. The speed of that "point of light" is "((radius of the moon times pi) divided by (1 nanosecond)) divided by the speed of light = 18 206 605.7" via Google. That's 18 million times the speed of light (probably around warp 7 or so
In the entangled penny example, Penny A could be at City A, Penny B could be at City B, entangled. But again, while City A and City B can affect the pennies, they can't affect the other penny in a detectable way. While they can 'collapse' Penny B's entangled state, you cannot detect uncollapsed states, so to them, nothing detectable happened. All that happens is that at the end of the day, City A and City B can look at their experimental results, and for every result City A gets, City B will get a result that corresponds to that result. But the individual results from City A and City B are random, just like the movement of that point of light.
It's exactly the same as a quantum shadow. City A and City B could communicate and be amazed that their two experiments agree perfectly, but neither of them can affect the outcome of the experiments. The only difference between the "point of light" and "entangled penny" bits is that in the point of light case, an observer on Earth was causing the changes, and in the entangled penny case, the Universe was causing the changes.
What's the point of civil disobedience if you don't get arrested for it? The whole idea is to get arrested to get publicity for your message and to put a stress on the system.
Because in this country, you are allowed to protest the current government without fear of being arrested. At least, you're supposed to be able to.
Yeah, I've notice that too. Any time you don't agree with some liberal person you'll ostracized as "stupid" or a "sheep".
First they came for the Democrats, and I did not complain because I was not a Democrat.
You should know the rest.
Give me a break. This is freedom of speech we're talking about here. And freedom of speech isn't about being able to write a nice, polite opinion piece that's "slightly" against the government stance. They could do that even in the worst times in the USSR. Freedom of speech is about protecting the worst kind of speech - the kind that is flagrantly opposed to the government order, Michael Moore type stuff. Freedom of speech should be restricted only very carefully - "clear and present danger" and all that. It's not "clear and present annoyance". Part of the cost of living in a free society is putting up with people who don't share your views.
If you can only protest "politely", it isn't America anymore. All activists have a right to have their case heard, because one of these years, people like them are going to be right.
You're really fixated on this Hitler stuff. When was the last time any liberal mentioned "Hitler" and "Bush" in the same sentence? And I'd like a link please, otherwise you're just trolling.
That wasn't the point. Read the two again.
The point was that the great-grandparent's argument for supporting Bush is crazy. You could've used it to support Hitler at the time (ignore what we know now - obviously few would've supported him had they known). His argument essentially is "yes, he's a jerk, he states things that are very dangerous to our fundamental way of life, and he lies to us... but I'm going to vote for him because I hate the fact that other people are making him out to be a demon, when he's not."
If you agree with someone's opinions, but not their tactics, you don't go out and do the exact opposite just to spite them. That's stupid. You should never, ever let your vote be influenced by anything other than the candidate and what they stand for. If you don't like the candidate, and don't want them in office, don't vote for them. Voting for someone because you don't like the opposition ("lesser of two evils") is crazy - especially if you don't actually like the candidate you're voting for.
But what do I know, that's just the whole "democracy" thing.
While the last really is a benefit java posesses the other two aren't that relevant.
True. The grandparent post, however, was saying that an interpreted language must be slower than native code. This was the point I was trying to show was wrong - Java isn't the "prime example" of interpreted code, in my opinion. I actually think the Transmeta processors are much better examples, and I think we would all realize this if Transmeta had the money to make a true performance processor.
If you realize that interpreted code, emulation, and whatever you want to call the "RISC-in-CISC" design of modern processors are all the same thing, then the statement I was making - that those can be faster than native code.
It all comes back to the halting problem, and Wikipedia has a great point here: imagine the following algorithm -
int main(void)
{
BigInt i, j, k;
for(i=j=k=1;--j||k;k=j?i%j?k:k-j:(j=i+=2));
return 0;
}
which looks for an odd perfect number, none of which are known to exist, but math has no idea whether or not they fundamentally do exist.
So there's no way the compiler can figure out that the comparison to stop the for loop may never come, but an interpreted language can notice that the likelihood of this branch ever being taken is virtually zero. There's in fact probably a formula for when the JIT compiler should start saying 'this branch will never happen - and if it does, the performance gains that come from assuming that it never happens will outweight the penalty for when it does'. Ballparking it, I can't imagine that it would take more than a hundred loops or so.
This is a bit of a poor example for an interpreted language, because there's not really any optimization that can be done here except branch prediction always assuming that the branch is not taken - although the JIT compiler could add the 'hint' to the hardware branch predictor of 'just ignore this branch' after it becomes obvious that the branch is never taken.
But you can imagine situations where an interpreted language could excel, especially given the relative "plateaus" of performance that modern PC's have:
registers>>L1-cache>>L2-cache>>main-memory>>har
If an interpreted language can shift a program from main-memory bound to L2-cache bound, it can improve the performance massively.
In particular Java is going to be slow because most JIT or interpreters I know of don't seem to remember things from one instance to the next
Which baffled me, especially considering that, for instance, the Sun JVM on Windows stays resident after loading for the first time. Completely bizarre. Apparently the Sun JVM is very good at optimizing for lots of branches and jumps, though - hence the reason that the simple "nested loops" example that I linked to performed so well in Java, even compared to the Intel compiler.
In essence, the interpreter should at the very *least* act like a gigantic BHT (branch history table) for the processor, and expect code segments to act exactly the same the next time they're run, or at least identify segments that run identically, and feed the processor "very-likely/very-not-likely" hints. Given the performance penalty for branch mispredicts, this could have a serious performance boost, especially on long-pipeline processors like the P4.
There is *no* way that a interpreted or JIT compiled language can be *faster* than native code.
Nope.
There are actually quite a few ways that an interpreted language can be faster than native code.
If you were right, then VLIW processors would've taken over long, long ago.
It's important to realize that the instruction set that any processor uses is not its native instruction set, for a long time now. Ever since the Pentium days, there's a "instruction decode" step in the pipeline, and even PPCs use it to pare down the (comparatively simpler) PPC instruction set to something more RISC-like.
So what does this have to do with programming languages, you might ask?
The point is that the analogy is exactly the same: VLIW processors rely on the instruction stream being very parallel, and well tuned to the architecture so that they can be very simple and very fast. There's only one problem - compilers can't be that smart. You don't have all the information until the program runs - this is very similar to the Halting problem. Until the program runs, you don't know how it will behave.
So what you're saying is "I don't see how an interpreted language can be faster than native code", likely because of the overhead. The answer to your "how" is that the interpreter - like any modern x86 computer - has more information available to it while its running than the compiler had when the program was compiled. Therefore the possibility exists that an interpreted language can outperform native code, because it can optimize for cases that the native code cannot. If that optimization is enough of an improvement over the overhead, you win.
It is for this reason that modern x86 computers perform so well compared to VLIW architectures - it's very difficult to extract parallelism from the code itself, before it's executed. It's actually more efficient to extract the parallelism while the code is actually running.
This is the exact same reason why Java can beat C++, in certain cases. And for benchmarks, http://cpp.student.utwente.nl/benchmark/. Note that this is in fact someone improving upon a C++ vs Java benchmark that showed Java won, so this is C++ striving as hard as it can.
Here you can see that for certain cases, Java can win. The most notable one is the nested-loop benchmark, where the Intel C++ compiler ran in 1.8 seconds, and the Java example ran at 1.05 seconds.
Your next statement might be that "yes, but in assembly..." and I will then say that yes, I highly doubt that you can find a Java program that will beat a hand-assembled piece of code. But it still is *possible*, because the interpreter may be able to perform some optimization during runtime that the person doing the coding can't because it's not strictly correct - this is akin to a branch predictor in hardware. It's allowed to cheat so long as it's later proved that it was right, but then pay a penalty when it's wrong.
Just like every other license, you have to have ownership before you can license it out. The GPL is no exception. You have to assign ownership to the FSF so that they can enforce the license.
Uh... what the hell are you talking about?
The only reason you would sign over copyright ownership to the FSF is if you wanted them to defend it in court because you aren't capable or willing to do it.
If you want to defend it in court, feel free. The FSF will be happy to help with any points relating to the GPL, of course.
Now that may be fine for someone else, but I'd never assign ownership of something I did to Stallman.
Neither did IBM. Hence the reason that they're suing for copyright infringement due to violation of the GPL for software they wrote, and which they hold the copyright on.
I think you're very, very misunderstood about what's needed to place a body of work under the GPL. You absolutely don't need to sign over copyright to the FSF. The FSF just recommends it for developers because most developers don't have the legal resources that the FSF has.
The GPL is designed to build up the body of free software to the level of pay software
No, it's not. The GPL is designed to ensure that when you place a body of work in the realm of free software, that it won't leave that realm of free software. That's all.
This is actually better for companies than the LGPL, because they are guaranteed that while they will get the support of the open source community, no competitor will be able to use that software, change it slightly, and release it again, without those changes being available to the company as well. So there's no risk associated with releasing the source code, other than opening the source code itself. With the BSD license there's a definite risk for businesses.
I think the BSD license is more appropriate for individual developers who are just coding for fun, actually.
Well, no - if you go look up gender, you get
You'll note that definition 1 is what you're saying - that's the grammatical definition. But definition 2 and 3 are what I was talking about - a table, to French speakers, is not "female". It's just "la table".
So we're both right, though maybe I should've said "medical gender" rather than "grammatical gender". Again, half the problem is that people mix the definitions of gender, and assume that since the French/Spanish/etc. language have a concept akin to definition 1, that that same concept must be definition 2,3 as well, and that's just poor teaching of the language.
Not a bad post, but this example doesn't work. There actually is a rule in English for when to use "more" and "most", and when to use "-er" and "-est"
There are rules for which words take female modifiers, and which words take male modifiers in Spanish, too. And just like in English, there are a few exceptions, as well.
That doesn't change the point of the example. The point is that Spanish speakers/French speakers don't attribute a "gender" to things just because the language makes it look like they do. It's just a curiousity of the language.
Is a table male or female? It's an IT to me, and that's the way it will stay.
It's an "it" to the French, too. It's not that the table 'has' gender - it's that the word belongs to a certain class of words that behave like it - that is, they're preceded by "la", "une", etc. In French, it's not "table", it's "la table" - the article is linked to the word itself (much like in English the infinitive is two words, but one idea).
In truth, it has nothing to do with the object itself. The French don't know why it's "la table" and not "le table", other than to tell you that it doesn't sound right as "le table".
The problem really comes because teachers like to teach it as if it really is confusing, and massively different from English, so you have to start seeing the gender in things. That's crazy. It's not different. It's just something you have to memorize, just like they have to memorize which adjectives you use "more", "most" with, and not "-er", "-est".
In truth, you can see the obvious bias in the study, as well. If your society has no language for counting above "two", then it likely has no need for counting above two, and so when presented with a situation where they need to count above two, they will be confused, because it's something they haven't done before. After all, when you're taught numbers, you're taught to count! So is it linguistic? I doubt it. I think the reverse is more true - thought (and society) shapes language.
I'd have to find out more about the study, but it seems really weak. You'd need a very careful control - that is, someone who lived in the same society as the Piraha, but spoke a different language that contained numbers higher than 2, and even that would be touchy because, as I said before, learning numbers above 2 means you were taught to count. But anyway, obviously no one like that exists, and I find it ludicrous that the psychologist made the leap "language directs thought" rather than "society directs language".
SCO's not claiming that anywhere. If they did that, they'd be laughed out of the courtroom, and then probably promptly sued by quite a few people. They can't usurp Linux developer's copyrights just because IBM did something. Linus and the other kernel developers still retain possession of the code they wrote.
SCO is only claiming that they have the rights to the code that IBM inserted into AIX and then transplanted into Linux. Maybe SCO believes what you're saying - if so, thank God, because there's not an intelligent lawyer on their entire staff. But their entire legal defense so far has never once tried to claim ownership of Linux. They can't.
Why SCO continued to distribute the Linux kernel, I have no idea. Why they tried to charge licenses for Linux, I have no idea. It was clearly illegal by the terms of the GPL, and as IBM is pointing out, SCO can't distribute anything without the GPL.
IBM is actually doing what several people on Slashdot suggested to several kernel developers: since SCO is distributing the Linux kernel in violation of the GPL, they are violating copyright, and can therefore be sued by the copyright holders, namely IBM. So IBM is suing to dismiss a claim, and to injoin SCO from distributing Linux. I honestly can't see how the judge will disagree. It's very clear cut copyright law. If the GPL is valid, they can't tack a more restrictive license onto it (which they did). If it's not valid, they couldn't distribute the code at all (which they did).
If SCO tries to claim ownership of Linux as a derivative work of AIX to defend itself, I'm sure the conversation will essentially be Since SCO claims full ownership of all the code in Linux
Really, honestly, they're not doing that. They've never claimed that in a court of law, and they never will. If they were, you wouldn't see Boies handling the case, anyway. You can't "usurp" copyrights from people, especially people you've never signed a contract with. There are 431 listed authors in the CREDITS list, and I'm sure none of them have transferred copyright to SCO. Thus, either the Linux kernel is completely undistributable (if it has SCO's IP in it) or it's distributable under the GPL. Either way, SCO couldn't distribute it the way they did.
I have no idea how SCO is going to respond to that motion. I don't know how they can, other than to feign ignorance about the distribution. If they try to claim that the GPL is invalid, and the code is in the public domain, IBM (and the judge - you can't "accidentally" give up copyright - SCO has actually said this themselves!) will rip them a new one. If they try to claim that they didn't know they were doing it, it'll shred their credibility in court. They were doing it up until August of this year! If that's true, the judge won't believe a word their executives say, because clearly they don't even know what their own company is doing. If they try to claim they hold the copyright to the code in Linux, see above. I'm really curious what they're going to say. It's damn funny.
SCO's argument is that code IBM added to AIX belongs to SCO, and that any derived work also belongs to SCO.
You're missing the grandparent's point: IBM has contributed code that has nothing to do with AIX, and would never work on AIX in any case, like the MWAVE driver or countless Thinkpad patches and drivers.
Unless SCO manages to convince the court that every single piece of code that IBM has written ever, there is no way that this summary judgement can't be granted.
just including JFS code in Linux gives SCO all rights to all parts of the kernel
Even if SCO's claim that by including the JFS code in AIX it becomes subject to the restrictions of the AIX license were true, this still won't give them any rights over the Linux kernel, which is protected by its own license.
The GPL is actually quite clear about this point - if the code is covered by a license that's mutually incompatible with the GPL, then you can't distribute it at all. So SCO is breaching IBM's copyright on all of the other code in Linux that has nothing to do with AIX, even if their bullshit claims about owning JFS code were true.
Basically it's similar to IBM's previous motion for judgement (which was: "Your Honor, we didn't do it. Even if we did, we have affadavits saying that we could've, and we have interviews saying that we could've, and we have this legal document from the real copyright holder saying we could've. But we didn't.") - it's "Your Honor, they're violating our copyright. Even if they own our code from AIX, which they don't, they're violating our copyright on many other pieces of code. And even if they're right that the GPL is invalid - which they aren't - they'd *still* be violating our copyright by distributing our code without a license."
No, ion drives do not have enough thrust to achieve escape velocity (25'000 mph for Earth).
They don't have enough thrust to reach escape velocity for Earth, and that's because there's this nasty blanket of stuff around us called the atmosphere.
There are mechanisms which generate far less thrust than an ion drive (the Yarkovsky effect: the differential light pressure between radiated photons and incoming photons due to rotation) and still push something to escape velocity. It won't work on Earth because static friction and air resistance reduce the net thrust to zero.
I don't think that's correct. One could easily imagine a parabolic path on which some solar sailboat is on, and reducing that velocity to below escape.
Depends which direction you're heading when you're at escape velocity. You can't slow radial velocity no matter what: if your radial component (outward) exceeds escape velocity, no solar sail could ever stop you: you're heading out of the system.
Any other direction, it's possible, however, it is actually harder: you can't reduce your tangential speed without increasing your radial speed slightly (because if the sail is edge on, there's no surface area) so there's actually a range of directions, centered on radially outward, where if you exceed solar escape velocity along any of those directions, you're leaving the neighborhood.
How? The flight path is always away from the Sun when you're on your way to pluto.
No solar sail could ever fully oppose the Sun's gravity unless it was, I dunno, half the size of Jupiter's orbit or something. OK, maybe not that large. But it'd be huge.
All you're doing is adding to your orbital speed by tilting the sail to accelerate along that direction. So you slowly spiral outwards.
To return, you just do the opposite: slow your rotation, and you spiral inward. You'll have to be careful to alter orbit at several points to circularize it (so you're not going at an insane speed when you hit the inner solar system), but it can be done.
The answer to 2 is no.
i ntro/tacking.html
Actually, it's yes: http://www.ugcs.caltech.edu/~diedrich/solarsails/
In space, there is no "water" for a rudder to work in
Actually, there kindof is : because all motion around the Sun is necessarily rotational (especially if you launch from Earth!), your tangential velocity is essentially your "water" - to fall inward, you angle the sail so that it slows you down, rotationally.
You could always cut the sail and let the Sun's gravity slow you...
Things going around the Sun are in orbit. There's no possible way that a solar sail could fully oppose gravity unless it were gigantic. Actually, that's not such a bad undergrad physics problem... anyway. The Sun's gravity wouldn't slow you down - it keeps you in orbit. You actually use the sail to slow you down, and then your slower orbital speed lets you fall in.
Sure, I can disable every network service
Which ones do you use? Now which ones does Joe Sixpack use? On a desktop, at home?
For a machine that browses the Web, what services do you need? Considering many people use the stock NATing routers as internet sharing devices, apparently most people don't need any network services. So long as they can get an outbound connection, the inbound ones don't seem to matter much.
For those that do, they should learn the dangers of the software that they're installing.
and use Lynx to browse the web...
Mozilla would be fine. Most of its recent security issues were Windows-only problems. And they were very minor, comparatively.
There are no breaks, but you CAN use it to manuver in any direction that is not 'up wind'.
No.
http://www.ugcs.caltech.edu/~diedrich/solarsails/
Solar sails can tack, because slowing your orbital velocity moves you closer to the Sun. If you put the sail at an angle such that majority of the light pressure opposes your direction of motion, you will move inward.
So to slow down, you just alter the angle of the sail. Easy enough.
No, the slowest part of PC's today is the user interface. The rate at which a user enters data (via keyboard/mouse) is a fraction of the rate at which a user thinks. (Your mileage may vary, of course.)
You're wrong.
$ mozilla &
7 characters * (1/500 cps) = 14 ms
That's 80 or so wpm, so maybe that's a bit fast. But still, 14 ms is on par with just the seek time of a hard drive, and that's not even considering the transfer. Plus I don't know *any* computer that can load Mozilla, uncached, in under 14 ms!
This is a computer, after all. One click could start a massive simulation, or switch between two programs that are each using 100M of memory, one of which is sitting in swap. Or it could open a 600M video file. Or it could type the letter "c" in a Word document, in which case you'd be correct. But that's not everything.
Applications today fall into one of four categories:
It'd be nice to believe that everything's sitting in the last category, but that's simply not true. Complicated simulations will sit in category 1 (along with Quake 3 at low resolutions, apparently). Media encoding will sit in category 2. Application launches sit in category 3. And most Office programs sit in category 4. The differences in speed between these categories are orders of magnitude
Category 1 increases regularly, by Moore's Whatever. Category 2 increases regularly due to industry improvements in memory design - still slower than category 1. Category 3 increases basically only due to rotational speed increases, and those are bounded by obvious laws of physics. I can't have a 500,000 rpm disk drive and expect to be able to read it easily. It's nice to see someone try to push Category 3 up to the same speed as Category 2.
I don't buy it, however, mainly because if you look at the transfer rates quoted, there's a huge variation: sustained R/W bandwidth: 14-110 MB/s? Who wants to bet that the "W" bandwidth is 14 MB/s, and the "R" bandwidth is 110 MB/s? Flash is notoriously slow at writing, and very fast at reading. Disks are quick at doing either.
Actually, I had a Red Hat 5.2 box installed in 1999 unfirewalled until just recently. It's never been rooted once, and I haven't installed an update on it for multiple years, other than to fix a bug in an app or two. It's not running any more, so don't bother with the "oh yah? well it will be now!" jokes. And yes, I do know that it wasn't rooted. I did check pretty carefully periodically, and the network admins were pretty careful about watching for suspicious traffic.
Why was it okay? That's simple enough - there were no vulnerable services running on it.
That particular machine was a very limited server - it didn't even respond to machines outside of the local subnet, but the argument applies even better to desktops. What server does a desktop *need* running? None.
This is the point - Linux can get rooted from servers, which you can avoid totally if you don't need the server. But Windows can be rooted from IE, or in the case of XP, through a service that's installed by default (that you pretty much *can't* disable before the installation's complete, so the machine would be rooted already). In other words, you can get rooted for just using Windows as a desktop. It's a bit harder with Linux.