A citation is clearly not needed for what is clearly an opinion....
That's certainly is fair enough, but if you are going to go that route then I am going to conclude that your opinion that "too many doctors, including psychiatrists, are too eager to prescribe a pill rather than taking the time to get to the root of the problem and fix what's really wrong" has absolutely no basis in fact and thus should not be given any credence.
Your post reminds me of a phenomenon that we call "intellectual phase locking" in physics. There have been times when a number of experiments would each other very precisely about what a measured constant should be, but then a later experiment with much greater precision would obtain a significantly different value. (Not a completely different value, mind you, just one that was outside of the expected range based on the average of the previous experiments.) This happened because the experimenters would tend to assume that if they got a different value than the previous experimenter, then the problem must be with their own experiment rather than with the previous result, so they would keep making adjustments to account for systematic errors. They did not think that they were biasing their results; they honestly believed that they were fixing problems in their experiments. However, the emergent effect was that experiments would tend to "lock" on a particular value for a while, even if that value was further from the true value than should have been the case from their error bars.
"I'd rather take my chances with God than with half of the drugs I see advertised"
Or better yet, do both. Use drugs to help you with problems that have physical origins, and prayer, etc. to help with the spiritual matters.
I had a couple of long discussions with a Catholic priest friend of mine, and one of the things that he talked about was how --- at least, in his community --- they really tried to identify the root cause of a person's mental problems, whether they be physiological, psychological, or spiritual, in order to make sure that the person was getting the correct type of help.
I am very sorry that SSRIs caused you a lot of suffering, however that does not mean that they do not work in general.
I take a SSRI (citalopram), and it has been a great help to me. Before I went on this drug, I would get into random funks that would last several days in which I felt like I would never be happy again. It wasn't that anything in particular was bugging me, it was that *everything* felt wrong, even though nothing in my life had actually changed.
The cool thing about the SSRI is that I don't go into funks for random reasons anymore. Now when I am feeling down about something, there is actually a real cause behind it, so if I can fix the cause then I feel better --- or at the very least, when I stop thinking about the problem then I don't feel as depressed anymore.
I am mentioning this because I think that there are a lot of misconceptions about what anti-depressants do that cause a lot of people to suffer unnecessarily, when there are treatments that can really help a lot. After all, there is already plenty that one has to deal with in life, so there's no point have having addition troubles loaded on your brain that aren't even being caused by something real.
"Unfortunately, too many doctors, including psychiatrists, are too eager to prescribe a pill rather than taking the time to get to the root of the problem and fix what's really wrong."
[citation needed], but regardless, some points in response:
First, one of the nice things about anti-depressants is that they give the patient a break from their strong emotions so that it becomes easier for them to do exactly as you say and fix the root of their problem.
Second, of course doctors and psychiatrists are more inclined to proscribe pills since that is their specialty, as they are the ones with M.D.s. If you're problems would better be fixed by talking to someone, then you are better off seeing a psychologist since talking through problems is their specialty, and they are generally cheaper per unit time since they don't have an M.D.
Finally, something else to keep in mind is that anti-depressants are in general cheaper than getting counseling, since there are plenty of good anti-depressants that are now generic. That doesn't mean that they are better, but I could see situations in which a patient might be put on anti-depressants rather than being referred to counseling since it is easier for them to afford.
When I have children, I am going to employ the internet in a simple but powerful strategy for homeschooling: I will have my children spend every minute of their day reading the comments on internet blogs, and then I will tell them, "From now on, be just like that, only the complete opposite."
I hope to produce intellectual and literary geniuses this way!
There is this thing, though, called snake oil. Politicians love it, these days even more so when it's 'Green Snake Oil'.
There is a fascinating disconnect between your posting and the lack of actual politicians claiming that this particular technology is going to solve all of our problems, as well as a lack of companies selling this product in large quantities to a deceived public.
Granted, it would seem that some people are really enthusiastic about how awesome this technology could be if it pans out. I fail to see how this is a bad thing. Haven't you ever gotten really enthusiastic about a project before? Didn't this enthusiasm motivate you to get started and see how far you could push your idea, even while a little part of you knew that realistically it probably wouldn't live up to all of your expectations?
Many of you here seem to be missing the point. The assumption here is that you WANT to have your project be publicized positively via some media outlet, in which case it is important to understand the conditions under which reporters are operating. If you really don't care whether the press writes about your project or what they say about it, then the advice in this story is not for you and you should feel free to ignore it.
In short, if you don't feel like doing the press any favors, then fine, you are certainly under no obligation to do so, and I doubt that they will think personally less of you for it; just don't expect them to bother about you in return.
While your point is well taken that one needs to take the Language Shootout with a grain of salt, on the other hand you have presented a benchmark that is over a year old, and the compilers have been evolving a *lot* since then, so it is probably *less* likely than the current language shootout to give a sense of relative speeds. Having said that, as another post has already mentioned, it is rather damning to the grandparent's case that Haskell currently doesn't actually have a compiling regex-dna solution posted on the Shootout.:-)
Also, I am not sure that Darcs is a good example because, as I understand it, the problem is not that it was written in Haskell, but that it uses its own unique algorithms based on an "algebra of patches" that tends to run slowly in practice, and in particular it has worst-cases scenarios where it runs in exponential time.
Fair questions. To answer your first question... I actually said something less clearly then I should have. When I said "the cutoff seems to be somewhere around a molecule", it sounded like I was saying that the cutoff was for objects that were molecules, but what I should have said was "the cutoff seems to be for phenomena that occur on a scale that is somewhere around the size of a molecule." That is, even though an electron is being involved, and an electron has the size of an infinitesimal point (as far as we know), since it is moving a distance that is on the scale of the size of a molecule, this movement would normally be a phenomena that could be described classically.
Put another way, the quantum "fuzziness" of the electron is normally just big enough that you can't really say where it is inside of an atom, but not so big that you can't say at which atom it is currently at. However, what this experiment showed is that the size of the fuzziness of the excited electron was (in a very rough manner of speaking) actually much larger than the size of an atom and encompassed about seven atoms of the molecule (if I recall the number correctly).
As for how you measure that the electron was really at two spots at once... I am a theorist rather than an experimentalist so unfortunately I don't have the exact tricks that they use stored in working memory (and they really do some impressive and clever things to tease out what's going on from deep within a system!), but the general idea can be illustrated by a simpler "thought experiment".
Imagine that you are sending water waves (not big ones; think ripples) through a wall that has two slits, and then a little further along you have a second wall with a bunch of detectors. In this system, two sources of waves are being generated between the two slits in the first wall. Now pick a particular point along the wall with your detectors. If you are clever, you can pick a spot so that whenever an "up" ripple has arrived from the first slit, a "down" ripple arrives from the second slit that cancels it out so that at that point in space the water is perfectly still and flat *at all times*. This is how you can tell that there were two sources of waves, since if there were only one there would be nothing to cancel the wave out and you would see it constantly rippling everywhere along the detector.
So suppose now that we are trying to distinguish between two different scenarios. In one case, I keep both slits open all of the time, and in the other case I repeatedly pick one slit at random and then open it just long enough for one ripple to pass through -- so in the first case each ripple ultimately passes through both slits (and is the source of "two" ripples on the other side), but in the second case it only passes through one, even though we don't know which. How could you tell these scenarios apart? By looking to see if there are points on the detector which are always perfectly flat, and other points which fluctuate, since this kind of pattern -- an "interference pattern" can *only* have come from two interfering waves.
In the case of "particles" -- which are all fundamentally waves that just happen to come in bunches and appear at points which creates the illusion that they are a particle (long story here;-) ) -- it really is the same idea, only with the subtlety that we can get the same effect as randomly closing one of the two slits by measuring which of the two slits the particle-wave had passed through, since this will force it to pick only one of the two slits (again, long story here). Put another way, the act of measurement forces the electron to act like a classical object and to only exist in one place instead of both at once, and so we can measure whether the electron acted like a classical object or a quantum object based on whether it created an interference pattern.
Now, you don't actually see a ripple at your detector but instead just get a number of "counts" of how many times an electron hit your det
As a quantum physicist, perhaps I can enlighten those of you whose ignorant "of course it's quantum physics! clearly this research is the st00p1d" comments have gained unseemly amounts of modpoints.
Yes, of course quantum mechanics is what is ultimately responsible for everything that happens in the world (at least, as far as we know, though general relativistic phenomena are so far an exception to this). However, despite this fact, it is remarkably the case that the world we perceive on our own macroscopic level does not behave in a quantum way at all, but instead seems to obey classical mechanics. Essentially what it comes down to is that at some point, things start interacting with their environment so much that they start being constantly measured, and so the quantum behaviour disappears. What is not so clear is at exactly what level the world stops being quantum and starts being classical.
In general, the cutoff seems to be somewhere around a molecule. That is although atoms and bonds between atoms are quantum effects, molecules tend be very well modeled using classical forces that were obtained from the quantum models of the bonds.
Because of this, before this research was done, a very reasonable educated guess for one to have made was that the first step of photosynthesis, where an electron essentially is knocked into walking from one part of the molecule to another, would be a classical process, since it happens on the scale of a molecule. Put another way, one might have guessed that when the electron walked from one part of the molecule to another, it did so in a classical (but non-deterministic) fashion by choosing one of the paths available to it and walking down that.
However, what this research has shown is that this is not the case. The electron in fact takes several paths at once. This was detected by performing experiments which showed that there were interference effects; this is the standard approach to take to determine whether something is quantum or classical by the following rough chain of reasoning: you can only see interference patterns when you have cancellations, and you can only see cancellations when something has taken two paths simultaneously but with the opposite phase, so ergo if you see an interference pattern then something quantum must be going on.
This is actually very remarkable because it means that nature specifically engineered a molecule that manifests quantum behaviour on a larger scale then it usually appears. This is a non-trivial thing to have done because, again, the fact that we don't usually see quantum behaviour on this scale implies that it is typically precluded by interactions with the environment, so the fact that this molecule accomplishes this means that it somehow evolved to isolate the electrons involved in photosynthesis from their environment in order to allow them to act in a quantum fashion.
It turns out that the gain from doing this is small, but notable; I didn't read the article, but I did talk to some of the people involved in this research at a couple of meetings and if recall correctly they said that according to their simulations, by doing this nature gained an efficiency of about 10% over what it would be able to get if it were only using classical phenomena. Thus, this effect is actually important for us to understand because it may give us insights into how we can engineer our own devices to use large-scale quantum phenomena to more efficiently harness energy from the sun.
Having glanced through the paper, I can tell you that it seems indeed to have been done over seven years, tracking individuals over time.
Ugh... your point that I should have included a link is well taken and I really would love to do so, but the only reason I was able to download the article for free was because I am a student at a University which subscribes to the journal.:-/
...except that the study didn't just show that people over 27 did less well on the score, but also that their scores on certain tests *declined over time*. Furthermore, on other tests the same groups did *increase* their scores over time.
So basically the problem with your theory that these results are being biased by declining interest is that it does not explain why, say, the ~ 45 age group had an increase in reasoning scores over a seven year period but a decrease in spatial orientation scores. (I downloaded the paper myself so this comes straight from a graph in the paper.)
...except that the study didn't just show that people over 27 did less well on the score, but also that their scores on certain tests *declined over time*.
So assuming your theory, which basically boils down to supposing that the older people who are taking this test are stupider then those who chose not to take the test and thus bias the outcome, you would also have to explain why this group also just happens to get less good at the test over time than the younger people.
Of course, I suppose it would be too much to assume that the people doing a study such as this probably know what they are doing and probably accounted for such an effect, since they are merely professional scientists and all.:-)
You missed his point. He wasn't criticizing your project, he was criticizing the way that your video presented it. Your video may have been good for the audience for which it was intended -- i.e., people who were already familiar with your project -- but for people who have never heard of your project before it was a bit incoherent and rambling which made it confusing to figure out what it does. (Nothing wrong with that, of course, since you are doing this in your free time fun, but I just figured you should be aware of how you were coming across in case you decided to care about it.)
Also, if I may humbly make a suggestion: as a general rule, when making a presentation it almost never helps you to throw in apologies, since you are more likely to remind people that they should be annoyed at you about something than you are to assuage people who already are annoyed at you. For example, there have been a couple of occasions I can think of off the top of my head where somebody said, "I know, I am sorry that I am horrible at drawing things!" as they were making drawings on a board, and it was only at the moment that I realized that, yes, indeed, his drawings were terrible -- and the irony is that if he hadn't said anything, then I probably would not have noticed since I was too busy paying attention to what he had to say.:-)
Anyway, best of luck with your project, and maybe to help the GP and the general Slashdot audience you could post a little bit if you want on what your project is actually about so that we could know why what you are doing is awesome.:-)
Actually, the best way that I've seen this done is in Haskell. There are braces and statement separators, but they are put in implicitly if you use whitespace to indent things properly. If you ever don't want to use indentation, however (say if you have just a couple of small things you'd rather have on a single line), then you can always bust out the braces.
First, here's a different spin on what E=mc^2 actually means. What it says is that if you want to measure the total internal energy of some object (i.e., the part that is independent of its kinetic energy), then all you have to do is measure its mass. This is actually a very remarkable fact because it says that you don't have to know anything about it's internal structure; instead, you only have to know one of two things: A) its weight in a gravitational field of known strength, or B) its acceleration in response to a known force. (The "equivalence principle" asserts that these two very different experiments actually measure the same quantity.) So in other words, you can take this "black box" and do an experiment on it that tells you its full internal energy.
Because of this, since we have done experiments of type (B) to measure the mass of the B_c meson (the particle of the article), we in principle already know its internal energy. However, in addition to knowing its mass, we also have a theory -- Quantum Chromodynamics -- that claims to tell us exactly what its internal structure is. One way to test this theory is be seeing whether the total energy it gives us of the particle is equal to what we measured via. its mass.
To see this in a different light, suppose that we were trying to figure out how much energy is in an oscillating spring, and the only measurement tool we had was the ability to weigh the spring very, very precisely. Then if we thought we had a theory for how much energy the oscillation contributes to the spring, one way could verify it would be by measuring the weight of the spring before and after we start it oscillating and checking whether the difference matches our independent calculation of what the energy should be based on our theory of how the oscillations work.
This is the spirit of what this calculation does. We know that the meson consists of two quarks, but like a spring there are all sorts of crazy oscillations going on that we are also trying to understand precisely. So given that we know the mass of the quarks, we can check to see if our theory of how much energy the "oscillations" contributed by the gluon field agrees with the mass of the meson (which is very roughly speaking, quarks + oscillations); of course, this alone doesn't tell us that Quantum Chromodynamics is the correct theory of nature, but if we didn't see agreement between the two calculations then we would have to re-think our theory.
The thing is, actually sitting down and calculating exactly what these oscillations contribute to the energy is very hard, which is why it has taken people so long to actually succeed in doing it. Now they have an answer: our theory does indeed predict the same quantity we see in nature, so in this respect it is not obviously wrong.:-)
2. Heisenberg principle: You inadvertently stumbled onto the problem yourself, kinda. When trying to measure the position of the electron, you use a high energy photon and this photon. When this high energy photon interacts with the electron it alters the velocity of the electron, so you know less about the velocity of the electron. When trying to measure the velocity of the electron, you use a low energy photon. This low energy photon measures the velocity well, but it moves the electron a little bit, so you don't know its position. This issue is the essence of the Heisenberg uncertainty principle.
Actually, the problem is more fundamental. What is really going on is that momentum = wavelength -- that is, what we perceive as momentum on a large scale is actually an average approximation of the existence of wavelength on a small scale. This is not intuitive at all; the only reason we believe it is because of countless experiments. But once you are willing to believe this, you see that it is logically impossible to know the position and momentum of a particle at the same time, even if you had the godlike power to measure the electron's properties without touching it. This is because for it to have both an exact momentum and an exact position, it would have to simultaneously be a perfectly non-localized wave and a perfectly localized point, which is nonsense.
Actually, as someone who's field is simulating quantum systems, I can tell you that the opposite is the case. "Spooky action at a distance", known in the field as "entanglement", means that in order to simulate a quantum system you need an amount of information that grows exponentially with the size of the system.
To see what I mean, contrast classical coins with "quantum" coins. If you want to see whether a set of classical coins is fair, you can test each one separately, since the probability of any particular outcome is the product of the probabilities associated with each coin. By contrast, "quantum" coins could have the property that they will all agree on "heads" or "tails". If you just looked at each coin separately you'd conclude that the set is fair, but it's not fair since the coins will always all get the same result. Other weird states are also possible, like having one and only one outcome be *impossible*, or having all the coins agree that only one of them will be "heads". So for quantum coins, your only recourse is to always flip all of them at once, and then keep track of the number of times you see each of the 2^N possible outcomes.
Actually, the grandparent was implicitly making the very reasonable point that we often see in this forum stories about how the United States government is screwing us over in some way, which upon further inspection turn out to be much ado about nothing.
Like when the government forcibly sterilized Native American Indian women? Or when the military conducted medical experiments on black airmen, giving them syphilis?
I think you missed the part where I said "in this forum". But don't let me interrupt your rant, though, since you seem to be enjoying it.:-)
Actually, the grandparent was implicitly making the very reasonable point that we often see in this forum stories about how the United States government is screwing us over in some way, which upon further inspection turn out to be much ado about nothing. Sometimes in fact the US government makes a decision which is good, but which is slanted on this forum to make it seem as if it were trying to hide something or screw us over.
Take the story about NASA not releasing all the details in its study of near-accidents in flying. So many people here were ready to say, "See? Yet another example of how the government will hide anything it can!" but in fact part of the point of the study was to promise that everyone submitting a report would remain anonymous, in order to encourage accurate and honest reporting. This was a good idea, but one that was nonetheless criticized by many simply because they didn't bother to learn the full story and just assumed it was a government cover-up.
So even though the US government has done and continues to do bad things, that does not mean that every time you read a Slashdot story you should assume that you have just learned about yet another bad thing it has done.
Quantum teleportation is nothing more than the equivalent of the MOV instruction on a quantum computer, with the oddity that this instruction actually does *move* the data, rather than copying it. As you can imagine, this is one of those basic instructions that you have to be able to implement properly in order to be able to have a quantum computer, which is why people are trying to get it right.
The reason it's called "teleportation" is just to emphasize that the data was once in one place and now is in another, in contrast to classical data which you can copy and so have in two places at once.
As for why you have to teleport the data, the answer is (very, very roughly) that if you were to copy the data then you would be overwriting a register somewhere, which destroys the data at that register; this is not allowed since you cannot destroy information in quantum mechanics. Put another way, you should always be able to construct any arbitrary past state of the universe given the present state; if you were allowed to overwrite a register with a new value, then you would lose the ability to figure out what value it had in the past, ergo copying is not allowed. (The more precise statement of this fact is the so-called "No-cloning Theorem".)
For those of you who know some quantum mechanics, here's what's going on:
The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.
This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state, there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)
So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP-complete problem.
There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states can decrease *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. In general systems do not behave this badly, but it is expected (and possibly has been shown, I don't remember) that systems which can solve NP-complete problems *do* behave this badly. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Mind you, you aren't *forced* to move so slowly, but if you don't then you have a good chance of effectively kicking the system into an excited state and thus ending up with something that is not a solution to your problem. Nonetheless, it's likely that you can get somehow a quadratic speed-up (equivalent to Grover's search algorithm) over classical computation by building such a computer.
This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case.:-)
The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.
This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)
So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP complete problem.
There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states decreases *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Nonetheless, it's likely that you can get a quadratic speed-up equivalent to Grover's search algorithm by building such a computer.
This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case.:-)
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A citation is clearly not needed for what is clearly an opinion....
That's certainly is fair enough, but if you are going to go that route then I am going to conclude that your opinion that "too many doctors, including psychiatrists, are too eager to prescribe a pill rather than taking the time to get to the root of the problem and fix what's really wrong" has absolutely no basis in fact and thus should not be given any credence.
Your post reminds me of a phenomenon that we call "intellectual phase locking" in physics. There have been times when a number of experiments would each other very precisely about what a measured constant should be, but then a later experiment with much greater precision would obtain a significantly different value. (Not a completely different value, mind you, just one that was outside of the expected range based on the average of the previous experiments.) This happened because the experimenters would tend to assume that if they got a different value than the previous experimenter, then the problem must be with their own experiment rather than with the previous result, so they would keep making adjustments to account for systematic errors. They did not think that they were biasing their results; they honestly believed that they were fixing problems in their experiments. However, the emergent effect was that experiments would tend to "lock" on a particular value for a while, even if that value was further from the true value than should have been the case from their error bars.
"I'd rather take my chances with God than with half of the drugs I see advertised"
Or better yet, do both. Use drugs to help you with problems that have physical origins, and prayer, etc. to help with the spiritual matters.
I had a couple of long discussions with a Catholic priest friend of mine, and one of the things that he talked about was how --- at least, in his community --- they really tried to identify the root cause of a person's mental problems, whether they be physiological, psychological, or spiritual, in order to make sure that the person was getting the correct type of help.
I am very sorry that SSRIs caused you a lot of suffering, however that does not mean that they do not work in general.
I take a SSRI (citalopram), and it has been a great help to me. Before I went on this drug, I would get into random funks that would last several days in which I felt like I would never be happy again. It wasn't that anything in particular was bugging me, it was that *everything* felt wrong, even though nothing in my life had actually changed.
The cool thing about the SSRI is that I don't go into funks for random reasons anymore. Now when I am feeling down about something, there is actually a real cause behind it, so if I can fix the cause then I feel better --- or at the very least, when I stop thinking about the problem then I don't feel as depressed anymore.
I am mentioning this because I think that there are a lot of misconceptions about what anti-depressants do that cause a lot of people to suffer unnecessarily, when there are treatments that can really help a lot. After all, there is already plenty that one has to deal with in life, so there's no point have having addition troubles loaded on your brain that aren't even being caused by something real.
"Unfortunately, too many doctors, including psychiatrists, are too eager to prescribe a pill rather than taking the time to get to the root of the problem and fix what's really wrong."
[citation needed], but regardless, some points in response:
First, one of the nice things about anti-depressants is that they give the patient a break from their strong emotions so that it becomes easier for them to do exactly as you say and fix the root of their problem.
Second, of course doctors and psychiatrists are more inclined to proscribe pills since that is their specialty, as they are the ones with M.D.s. If you're problems would better be fixed by talking to someone, then you are better off seeing a psychologist since talking through problems is their specialty, and they are generally cheaper per unit time since they don't have an M.D.
Finally, something else to keep in mind is that anti-depressants are in general cheaper than getting counseling, since there are plenty of good anti-depressants that are now generic. That doesn't mean that they are better, but I could see situations in which a patient might be put on anti-depressants rather than being referred to counseling since it is easier for them to afford.
When I have children, I am going to employ the internet in a simple but powerful strategy for homeschooling: I will have my children spend every minute of their day reading the comments on internet blogs, and then I will tell them, "From now on, be just like that, only the complete opposite."
I hope to produce intellectual and literary geniuses this way!
There is this thing, though, called snake oil. Politicians love it, these days even more so when it's 'Green Snake Oil'.
There is a fascinating disconnect between your posting and the lack of actual politicians claiming that this particular technology is going to solve all of our problems, as well as a lack of companies selling this product in large quantities to a deceived public.
Granted, it would seem that some people are really enthusiastic about how awesome this technology could be if it pans out. I fail to see how this is a bad thing. Haven't you ever gotten really enthusiastic about a project before? Didn't this enthusiasm motivate you to get started and see how far you could push your idea, even while a little part of you knew that realistically it probably wouldn't live up to all of your expectations?
Many of you here seem to be missing the point. The assumption here is that you WANT to have your project be publicized positively via some media outlet, in which case it is important to understand the conditions under which reporters are operating. If you really don't care whether the press writes about your project or what they say about it, then the advice in this story is not for you and you should feel free to ignore it.
In short, if you don't feel like doing the press any favors, then fine, you are certainly under no obligation to do so, and I doubt that they will think personally less of you for it; just don't expect them to bother about you in return.
While your point is well taken that one needs to take the Language Shootout with a grain of salt, on the other hand you have presented a benchmark that is over a year old, and the compilers have been evolving a *lot* since then, so it is probably *less* likely than the current language shootout to give a sense of relative speeds. Having said that, as another post has already mentioned, it is rather damning to the grandparent's case that Haskell currently doesn't actually have a compiling regex-dna solution posted on the Shootout. :-)
Also, I am not sure that Darcs is a good example because, as I understand it, the problem is not that it was written in Haskell, but that it uses its own unique algorithms based on an "algebra of patches" that tends to run slowly in practice, and in particular it has worst-cases scenarios where it runs in exponential time.
Fair questions. To answer your first question... I actually said something less clearly then I should have. When I said "the cutoff seems to be somewhere around a molecule", it sounded like I was saying that the cutoff was for objects that were molecules, but what I should have said was "the cutoff seems to be for phenomena that occur on a scale that is somewhere around the size of a molecule." That is, even though an electron is being involved, and an electron has the size of an infinitesimal point (as far as we know), since it is moving a distance that is on the scale of the size of a molecule, this movement would normally be a phenomena that could be described classically.
Put another way, the quantum "fuzziness" of the electron is normally just big enough that you can't really say where it is inside of an atom, but not so big that you can't say at which atom it is currently at. However, what this experiment showed is that the size of the fuzziness of the excited electron was (in a very rough manner of speaking) actually much larger than the size of an atom and encompassed about seven atoms of the molecule (if I recall the number correctly).
As for how you measure that the electron was really at two spots at once... I am a theorist rather than an experimentalist so unfortunately I don't have the exact tricks that they use stored in working memory (and they really do some impressive and clever things to tease out what's going on from deep within a system!), but the general idea can be illustrated by a simpler "thought experiment".
Imagine that you are sending water waves (not big ones; think ripples) through a wall that has two slits, and then a little further along you have a second wall with a bunch of detectors. In this system, two sources of waves are being generated between the two slits in the first wall. Now pick a particular point along the wall with your detectors. If you are clever, you can pick a spot so that whenever an "up" ripple has arrived from the first slit, a "down" ripple arrives from the second slit that cancels it out so that at that point in space the water is perfectly still and flat *at all times*. This is how you can tell that there were two sources of waves, since if there were only one there would be nothing to cancel the wave out and you would see it constantly rippling everywhere along the detector.
So suppose now that we are trying to distinguish between two different scenarios. In one case, I keep both slits open all of the time, and in the other case I repeatedly pick one slit at random and then open it just long enough for one ripple to pass through -- so in the first case each ripple ultimately passes through both slits (and is the source of "two" ripples on the other side), but in the second case it only passes through one, even though we don't know which. How could you tell these scenarios apart? By looking to see if there are points on the detector which are always perfectly flat, and other points which fluctuate, since this kind of pattern -- an "interference pattern" can *only* have come from two interfering waves.
In the case of "particles" -- which are all fundamentally waves that just happen to come in bunches and appear at points which creates the illusion that they are a particle (long story here ;-) ) -- it really is the same idea, only with the subtlety that we can get the same effect as randomly closing one of the two slits by measuring which of the two slits the particle-wave had passed through, since this will force it to pick only one of the two slits (again, long story here). Put another way, the act of measurement forces the electron to act like a classical object and to only exist in one place instead of both at once, and so we can measure whether the electron acted like a classical object or a quantum object based on whether it created an interference pattern.
Now, you don't actually see a ripple at your detector but instead just get a number of "counts" of how many times an electron hit your det
As a quantum physicist, perhaps I can enlighten those of you whose ignorant "of course it's quantum physics! clearly this research is the st00p1d" comments have gained unseemly amounts of modpoints.
Yes, of course quantum mechanics is what is ultimately responsible for everything that happens in the world (at least, as far as we know, though general relativistic phenomena are so far an exception to this). However, despite this fact, it is remarkably the case that the world we perceive on our own macroscopic level does not behave in a quantum way at all, but instead seems to obey classical mechanics. Essentially what it comes down to is that at some point, things start interacting with their environment so much that they start being constantly measured, and so the quantum behaviour disappears. What is not so clear is at exactly what level the world stops being quantum and starts being classical.
In general, the cutoff seems to be somewhere around a molecule. That is although atoms and bonds between atoms are quantum effects, molecules tend be very well modeled using classical forces that were obtained from the quantum models of the bonds.
Because of this, before this research was done, a very reasonable educated guess for one to have made was that the first step of photosynthesis, where an electron essentially is knocked into walking from one part of the molecule to another, would be a classical process, since it happens on the scale of a molecule. Put another way, one might have guessed that when the electron walked from one part of the molecule to another, it did so in a classical (but non-deterministic) fashion by choosing one of the paths available to it and walking down that.
However, what this research has shown is that this is not the case. The electron in fact takes several paths at once. This was detected by performing experiments which showed that there were interference effects; this is the standard approach to take to determine whether something is quantum or classical by the following rough chain of reasoning: you can only see interference patterns when you have cancellations, and you can only see cancellations when something has taken two paths simultaneously but with the opposite phase, so ergo if you see an interference pattern then something quantum must be going on.
This is actually very remarkable because it means that nature specifically engineered a molecule that manifests quantum behaviour on a larger scale then it usually appears. This is a non-trivial thing to have done because, again, the fact that we don't usually see quantum behaviour on this scale implies that it is typically precluded by interactions with the environment, so the fact that this molecule accomplishes this means that it somehow evolved to isolate the electrons involved in photosynthesis from their environment in order to allow them to act in a quantum fashion.
It turns out that the gain from doing this is small, but notable; I didn't read the article, but I did talk to some of the people involved in this research at a couple of meetings and if recall correctly they said that according to their simulations, by doing this nature gained an efficiency of about 10% over what it would be able to get if it were only using classical phenomena. Thus, this effect is actually important for us to understand because it may give us insights into how we can engineer our own devices to use large-scale quantum phenomena to more efficiently harness energy from the sun.
Having glanced through the paper, I can tell you that it seems indeed to have been done over seven years, tracking individuals over time.
Ugh... your point that I should have included a link is well taken and I really would love to do so, but the only reason I was able to download the article for free was because I am a student at a University which subscribes to the journal. :-/
...except that the study didn't just show that people over 27 did less well on the score, but also that their scores on certain tests *declined over time*. Furthermore, on other tests the same groups did *increase* their scores over time.
So basically the problem with your theory that these results are being biased by declining interest is that it does not explain why, say, the ~ 45 age group had an increase in reasoning scores over a seven year period but a decrease in spatial orientation scores. (I downloaded the paper myself so this comes straight from a graph in the paper.)
...except that the study didn't just show that people over 27 did less well on the score, but also that their scores on certain tests *declined over time*.
So assuming your theory, which basically boils down to supposing that the older people who are taking this test are stupider then those who chose not to take the test and thus bias the outcome, you would also have to explain why this group also just happens to get less good at the test over time than the younger people.
Of course, I suppose it would be too much to assume that the people doing a study such as this probably know what they are doing and probably accounted for such an effect, since they are merely professional scientists and all. :-)
You missed his point. He wasn't criticizing your project, he was criticizing the way that your video presented it. Your video may have been good for the audience for which it was intended -- i.e., people who were already familiar with your project -- but for people who have never heard of your project before it was a bit incoherent and rambling which made it confusing to figure out what it does. (Nothing wrong with that, of course, since you are doing this in your free time fun, but I just figured you should be aware of how you were coming across in case you decided to care about it.)
Also, if I may humbly make a suggestion: as a general rule, when making a presentation it almost never helps you to throw in apologies, since you are more likely to remind people that they should be annoyed at you about something than you are to assuage people who already are annoyed at you. For example, there have been a couple of occasions I can think of off the top of my head where somebody said, "I know, I am sorry that I am horrible at drawing things!" as they were making drawings on a board, and it was only at the moment that I realized that, yes, indeed, his drawings were terrible -- and the irony is that if he hadn't said anything, then I probably would not have noticed since I was too busy paying attention to what he had to say. :-)
Anyway, best of luck with your project, and maybe to help the GP and the general Slashdot audience you could post a little bit if you want on what your project is actually about so that we could know why what you are doing is awesome. :-)
Actually, the best way that I've seen this done is in Haskell. There are braces and statement separators, but they are put in implicitly if you use whitespace to indent things properly. If you ever don't want to use indentation, however (say if you have just a couple of small things you'd rather have on a single line), then you can always bust out the braces.
We can always offer a refund if you're in the spot that got hit.
Better yet, we'll say that if we screw up and you get hit, then the next asteroid defense is free!
Okay, so here's my take on all of this.
First, here's a different spin on what E=mc^2 actually means. What it says is that if you want to measure the total internal energy of some object (i.e., the part that is independent of its kinetic energy), then all you have to do is measure its mass. This is actually a very remarkable fact because it says that you don't have to know anything about it's internal structure; instead, you only have to know one of two things: A) its weight in a gravitational field of known strength, or B) its acceleration in response to a known force. (The "equivalence principle" asserts that these two very different experiments actually measure the same quantity.) So in other words, you can take this "black box" and do an experiment on it that tells you its full internal energy.
Because of this, since we have done experiments of type (B) to measure the mass of the B_c meson (the particle of the article), we in principle already know its internal energy. However, in addition to knowing its mass, we also have a theory -- Quantum Chromodynamics -- that claims to tell us exactly what its internal structure is. One way to test this theory is be seeing whether the total energy it gives us of the particle is equal to what we measured via. its mass.
To see this in a different light, suppose that we were trying to figure out how much energy is in an oscillating spring, and the only measurement tool we had was the ability to weigh the spring very, very precisely. Then if we thought we had a theory for how much energy the oscillation contributes to the spring, one way could verify it would be by measuring the weight of the spring before and after we start it oscillating and checking whether the difference matches our independent calculation of what the energy should be based on our theory of how the oscillations work.
This is the spirit of what this calculation does. We know that the meson consists of two quarks, but like a spring there are all sorts of crazy oscillations going on that we are also trying to understand precisely. So given that we know the mass of the quarks, we can check to see if our theory of how much energy the "oscillations" contributed by the gluon field agrees with the mass of the meson (which is very roughly speaking, quarks + oscillations); of course, this alone doesn't tell us that Quantum Chromodynamics is the correct theory of nature, but if we didn't see agreement between the two calculations then we would have to re-think our theory.
The thing is, actually sitting down and calculating exactly what these oscillations contribute to the energy is very hard, which is why it has taken people so long to actually succeed in doing it. Now they have an answer: our theory does indeed predict the same quantity we see in nature, so in this respect it is not obviously wrong. :-)
Actually, the problem is more fundamental. What is really going on is that momentum = wavelength -- that is, what we perceive as momentum on a large scale is actually an average approximation of the existence of wavelength on a small scale. This is not intuitive at all; the only reason we believe it is because of countless experiments. But once you are willing to believe this, you see that it is logically impossible to know the position and momentum of a particle at the same time, even if you had the godlike power to measure the electron's properties without touching it. This is because for it to have both an exact momentum and an exact position, it would have to simultaneously be a perfectly non-localized wave and a perfectly localized point, which is nonsense.
Actually, as someone who's field is simulating quantum systems, I can tell you that the opposite is the case. "Spooky action at a distance", known in the field as "entanglement", means that in order to simulate a quantum system you need an amount of information that grows exponentially with the size of the system.
To see what I mean, contrast classical coins with "quantum" coins. If you want to see whether a set of classical coins is fair, you can test each one separately, since the probability of any particular outcome is the product of the probabilities associated with each coin. By contrast, "quantum" coins could have the property that they will all agree on "heads" or "tails". If you just looked at each coin separately you'd conclude that the set is fair, but it's not fair since the coins will always all get the same result. Other weird states are also possible, like having one and only one outcome be *impossible*, or having all the coins agree that only one of them will be "heads". So for quantum coins, your only recourse is to always flip all of them at once, and then keep track of the number of times you see each of the 2^N possible outcomes.
I think you missed the part where I said "in this forum". But don't let me interrupt your rant, though, since you seem to be enjoying it. :-)
Actually, the grandparent was implicitly making the very reasonable point that we often see in this forum stories about how the United States government is screwing us over in some way, which upon further inspection turn out to be much ado about nothing. Sometimes in fact the US government makes a decision which is good, but which is slanted on this forum to make it seem as if it were trying to hide something or screw us over.
Take the story about NASA not releasing all the details in its study of near-accidents in flying. So many people here were ready to say, "See? Yet another example of how the government will hide anything it can!" but in fact part of the point of the study was to promise that everyone submitting a report would remain anonymous, in order to encourage accurate and honest reporting. This was a good idea, but one that was nonetheless criticized by many simply because they didn't bother to learn the full story and just assumed it was a government cover-up.
So even though the US government has done and continues to do bad things, that does not mean that every time you read a Slashdot story you should assume that you have just learned about yet another bad thing it has done.
Quantum teleportation is nothing more than the equivalent of the MOV instruction on a quantum computer, with the oddity that this instruction actually does *move* the data, rather than copying it. As you can imagine, this is one of those basic instructions that you have to be able to implement properly in order to be able to have a quantum computer, which is why people are trying to get it right.
The reason it's called "teleportation" is just to emphasize that the data was once in one place and now is in another, in contrast to classical data which you can copy and so have in two places at once.
As for why you have to teleport the data, the answer is (very, very roughly) that if you were to copy the data then you would be overwriting a register somewhere, which destroys the data at that register; this is not allowed since you cannot destroy information in quantum mechanics. Put another way, you should always be able to construct any arbitrary past state of the universe given the present state; if you were allowed to overwrite a register with a new value, then you would lose the ability to figure out what value it had in the past, ergo copying is not allowed. (The more precise statement of this fact is the so-called "No-cloning Theorem".)
For those of you who know some quantum mechanics, here's what's going on:
:-)
The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.
This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state, there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)
So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP-complete problem.
There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states can decrease *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. In general systems do not behave this badly, but it is expected (and possibly has been shown, I don't remember) that systems which can solve NP-complete problems *do* behave this badly. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Mind you, you aren't *forced* to move so slowly, but if you don't then you have a good chance of effectively kicking the system into an excited state and thus ending up with something that is not a solution to your problem. Nonetheless, it's likely that you can get somehow a quadratic speed-up (equivalent to Grover's search algorithm) over classical computation by building such a computer.
This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case.
The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.
:-)
This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)
So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP complete problem.
There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states decreases *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Nonetheless, it's likely that you can get a quadratic speed-up equivalent to Grover's search algorithm by building such a computer.
This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case.