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If a thing's worth doing, it is worth doing badly. -- G.K. Chesterton
If a thing's worth doing, it is worth doing badly. -- G.K. Chesterton
At Last... Certainty! (Score:3, Funny)
Re:At Last... Certainty! (Score:1)
Re:Heisen-Haiku (Score:2)
Somebody comes up with an equation
Werner looks like fool.
EBADHAIKU
Re:Heisen-Haiku [NvwsCoach / CKW #2] (Score:1)
I'm sorry for not being able to coach you lately, but I'll try to make it up for you.
Your haiku was written incorrectly, and you should fix that. Please go to http://www.toyomasu.com/haiku/ [toyomasu.com] for more information.
I find this very familiar... (Score:2, Funny)
This describes the management at my last job, quite well. They had know idea of where they where going, but it went really fast.
Most employees jumped ship, before it was too late.
Joined the millitary... (Score:1)
5-7-5 (Score:4, Funny)
That God really does play dice
With the universe
Re:5-7-5 (Score:3, Funny)
We measure momentum? (Score:1)
That's quite a trick (Score:1)
Did Breck Shampoo provide the funding for this?
Help me... (Score:2)
Re:Help me... (Score:2)
I thought the heisenberg equation gave uncertainty as err(momentum * position) > CONSTANT, where the constant was some defined number (which I don't know offhand). So does this define the CONSTANT more accurately, or did Heisenberg just say the constant exists, and now we have a figure?
Heisenberg said err(momentum * position) >= CONSTANT. This says err(momentum * position)=(some equation).
Re:Help me... (Score:1)
Re:Help me... (Score:1)
Our mathematical abilities are far... far from those necessary to fully understand the universe.
Re:Help me... (Score:3, Informative)
Re:Help me... (Score:3, Informative)
No, he said err(momentum)*err(position)>=constant.
Re:Help me... (Score:1)
No, he said err(momentum)*err(position)>=constant.
Yes, yes, you're right. (Does "momentum * position" even make sense?)
Re:Help me... (Score:2)
Re:Help me... (Score:1)
The principal states:
err(momentum) * err(position) <= Plank's Constant / 4 * PI.
Plank's Constant, called h is often found divided by 2 * PI and the result is called h bar written as an h with a line through the top so the principal is usually written as:
err(momentum) * err(position) <= h-bar / 2
Bah! (Score:1)
Physics fascinates me (Score:2)
I'd rather not school for it, since I don't trust the quality of even the best Uni education.
I'd rather read. Anyone got a good 'get up to speed' reading list?
Re:Physics fascinates me (Score:1)
As far as speed reading goes, I would recommend you take a look at http://www.the-reading-edge.com/ [the-reading-edge.com]. I went through their program and can know scan /. at amazing speed. For example, I read this whole page in 2 seconds, with perfect comprehension.
Re:Physics fascinates me (Score:4, Insightful)
And if math isn't easy for you (and I mean math, not namby-pamby arithematic, I mean real math, like topology and geometry and all forms of calculus), and you aren't truly seriously motivated to spend years on this, even the Uni won't be enough; most people drop out of the serious Physics courses!
I can't give you a reading list; all I can say is if anyone else gives you one, and you can understand the books past the third chapter (assuming you know little/nothing about the subject, which I'm inferring from not trusting Uni educations right where they are the absolute strongest (hard sciences)), you're getting a "Slashdot" understanding, i.e., absolute crap. This isn't really a reading list problem; more of a reading bookshelf thing.
Quantum mechanics drives PhDs nuts; you probably aren't going to just "pick it up". And I say this as a guy who "picks things up" pretty routinely (not just computer stuff). You have to know your limits, and if you're asking, this is extremely highly likely this is beyond yours. (And if you have trouble understanding that sentence literally, don't even bother starting... statistically, there's a chance I'm wrong but I wouldn't bet, well, anything on that remote chance.)
Now, if you don't mind being a poser, as I am, then there are lots of great choices; the best thing to do is hike on down to a good physical bookstore, peruse the science shelves, and look for something that looks to be at your level, or better, slightly above. But don't think for a second you're getting anything more then the cliff notes of the cliff notes of a summary of quantum physics. (And highly opinionated ones, too; when physicist run out of math to talk about in popular-interest books, they tend to start shooting their mouths off and irresponsibly speculating wildly about cosmology. It makes good copy, but frankly, they're only slightly better equipped to speculate about the nature of the universe then you are; if anything, they get to be even more wildly wrong. You gotta seperate the physicist's wanking from the real facts.)
Re:Physics fascinates me (Score:1)
And highly opinionated ones, too; when physicist run out of math to talk about in popular-interest books, they tend to start shooting their mouths off and irresponsibly speculating wildly about cosmology. It makes good copy, but frankly, they're only slightly better equipped to speculate about the nature of the universe then you are; if anything, they get to be even more wildly wrong. You gotta seperate the physicist's wanking from the real facts.
In which category are the "A brief history of time", and Stephen Hawking's latest book (i dont remember the name - universe in a nutshell or something)?
Re:Physics fascinates me (Score:1)
Re:Physics fascinates me (Score:1)
Solving the Quantum Mysteries (Score:1)
A reading list [Re:Physics fascinates me] (Score:5, Informative)
Okay, you want a reading list. I have one for you.
First brush up on your classical mechanics, you will need to study Lagragians and the Hamitonian formulation as they are both very important for the formation of Quantum Mechanics. Lets see, you could try:
For a good mathematical methods reference read:
You want to rigorously learn all of Electricity and Magentism; there is only one source:
Now you have to start on Quantum Mechanics. There are many different books you could try; here are some of them:
Now that you have learned Quantum Machanics you can move onto some field theory:
At this point you may want to deviate slightly and read some books on relativity and cosmology
When I started college, I chose physics because I liked it. I soon realized that the physics you learn at a univeristy is not the physics a physicists does. Instead, everything you learn as an undergraduate classes are tools. These tools are to be used in graduate school as a foundation for more complex concepts.
It's been four years and I am about to go off to grad school to study elementry particle physics (experimental). I don't claim to have read any of the books above, but I hope it might show you that if you want to "*fully* comprehend stuff like particle physics, quantum phenomena, etc." it is not easy. Most popular science books you will find on a bookshelf do not contain much substance. Many are good reads. Brian Green's Elegant Universe and Stephen Hawking's A Brief History are good examples that are constantly recommended here on slashdot. But if you really (and I mean really) want to learn physics, you can do one of two things:
My purpose of this post is not to be harsh, but realistic. I am glad you are fasinated with physics. My fasination led me to the point where I want to spend years in school studying it. But I think many people don't realize that the subject is really difficult, and that it takes years of university education to even begin to understand it.
Re:A reading list [Re:Physics fascinates me] (Score:2)
Re:A reading list [Re:Physics fascinates me] (Score:1)
However, I would add Griffiths Introduction to Electrodynamics before Jackson as a much more approachable and physical textbook. Jackson is kind almost more of a course in solving PDEs under insane boundary conditions.
And, for physical insight, I would add the Feynman Lectures. The examples are well thought out, and they're kind of fun to read in their own right. But, these are for reading after you understand the math; before hand, they're practically useless.
I would also tend to add a few books in the Landau and Lifshitz series, most noteably their Mechanics and their Quantum Mechanics books.
And I agree, that a realistic foray into physics is not to be undertaken lightly. It takes years to get to the point where you can even begin to read journal articles and begin to understand them.
Re:Physics fascinates me (Score:3, Interesting)
Re:Physics fascinates me (Score:1)
Does God really play dice? (Score:1)
intellectual fraud (Score:3, Insightful)
[To the author of the post to which I am replying: please, don't take this as an attack on you.]
The "Heisenburg [sic] uncertainty prinicple [sic]" is not a misconception arising from inexact experimental tools; it has nothing to do with the quality of experimental means. The inequality that some (most?) physicists like to call the Heisenberg Uncertainty Principle is not a principle at all but a sort of litmus test for the applicability of classical models to systems exhibiting so-called quantum behavior; that is, the Heisenberg inequality can be used as a way to determine whether a given so-called classical model {still | no-longer} constitutes an accurate description of the behavior of the system in question. I suppose I could agree with someone saying that the Heisenberg inequality was a "feature" of quantum-mechanical models much more readily than I could agree with someone claiming that it was a principle. (You might look up "principle" in the dictionary to see what I mean.)
There's no "growing school of thought" to speak of because Physics is not a belief system, and I don't even think that a significant change in the thinking of the average physicist is currently taking place. There are many practicing physicists who haven't the integrity to admit (to others or to themselves) that they are a fraud and who propagate their misunderstanding to their students and to the public through their lectures and their publications -- and it may well be that attrition and budget cuts are weeding these posers out. Evidently, however, we've still a long way to go: the closing paragraph of the scholarly paper referenced in the story demonstrates how Ye Olde Rhetorick can survive even the strongest refutation. I can think of two reasons why people will continue to "believe in" the Heisenberg Uncertainty Principle and other such historically justified nonsense:
Fear not for the fate of science, though: it is quite possible to use the knowledge framework developed by Real Scientists (amongst whom I would include Real Mathematicians) to make Real Discoveries and devise Real Technology -- even in the absence of Real Understanding. (I am confident that the reader can provide his own examples. :-> ) And, in a very real way, we depend on these contributions to build the venerable edifice of science.
conclusion/ posers in the scientific establishment (Score:3, Informative)
That depends on whether you can infer that which I may have been too chicken to say more intelligibly. I realize you might be trolling me, but that's OK. The previous post dealt with two issues: (1) the trouble with referring to the Heisenberg inequality as the Heisenberg Uncertainty Principle and (2) the larger problem of which the foregoing is only a symptom. Since I believe the first point was adequately explained in my previous post, I will only elaborate on the second point.
A great many people who would call themselves scientists are posers, and some of them are outright frauds. A great many professors do not really understand much of what they teach; they cover up their incompetence by assigning buttloads of homework, giving clever problems on tests that are designed to prey on students' lack of experience, and avoiding truly open discussion with their students lest their own ignorance be revealed in the process. A great many researchers do not understand much of the theoretical framework they employ; they cover up their incompetence by doing lots of (often unnecessary) laboratory work (they say "experiments") or writing computer programs (they say "simulations"), writing karmawhorific articles for so-called scholarly journals, and avoiding truly open discussion with their peers lest their own ignorance be revealed and their peers aggravated in the process.
Yep, the scientific establishment is currently overrun by conniving intellectual midgets who pose as Real Scientists and uncritically certify each other. That may be disappointing, but it doesn't have to be a Bad Thing. If the goal is simply to catalog natural phenomena, discover new materials, and characterize known materials in order to exploit all this knowledge in "new technologies", then it may be acceptable for science professionals to be intellectual frauds because their incompetence will not prevent them from making a useful contribution. In fact, as long as there are a few Real Scientists around to straighten things out, the work of so-so scientists can be quite useful even when it does not consist of observation and classification. Consider, for example, the journal article to which the story refers: the article's closing paragraph gives me ample reason to believe that the authors have either (1) not properly understood their own result or (2) chosen to lean on the traditional aesthetic (and perhaps the dogma -- I'd have to talk to them to find out) in order to gain the favor of their peers -- but this does not in itself detract from the value of the result they present, which must be judged independently. [FYI, my previous post [slashdot.org] addresses conventional discourse on the Uncertainty Principle and gives context to the previous statement.]
So, that was my conclusion: many scientists (including, apparently, the authors of the article in question) are posers of one kind or another -- and that's probably OK. Mediocrity, when effective, is often also efficient, especially when combined with connivance. That may be hard for individuals of unassailable integrity (Real Physicists and Real Programmers included) to accept, but we have every indication that it is true.
[Disclaimer: I am a scientist (what you might call a mathematical physicist) and I hope, someday, before I am too old, to discover whether I, too, am a fraud. The last thing I want is to waste my life publishing bullshit articles in order to legitimize my last bullshit grant and support my next bullshit grant application.]
Re:conclusion/ posers in the scientific establishm (Score:1)
As far as there being a large number of fakers among scientists, I think it's pretty much true of any field - it's just more easily measured in science. Science is the big leagues, and only the elite of the elite can make a serious, meaningful long-term contribution. Of course the fakers can pose and pontificate as is done in other fields, and for a time it can succeed, but in the end the data tell the tale, and no amount of rhetoric can change that.
As for finding out if you're not one of the elite, well, almost nobody is. So what do you do if you realize you're Salieri instead of Mozart, and you are this close to being great but instead have only the still rare ability to fully appreciate the game, but are not allowed to play? You face the fact and you realize that that's the hand you were dealt, and you're stuck with it, and you won't get a second chance, so all you can do is make the best of it and make your life as comfortable as you can while you coast along towards obscurity, like almost everyone else. You're just one of the ones with the power to see your fate, instead of one of the oblivious teeming millions.
Re:intellectual fraud (Score:2)
Re:intellectual fraud (Score:1)
However, I am still wondering (1) whether you read the interview [gilder.com] with Mead about his book [amazon.com], or are just taking the first part of Elby's [slashdot.org] quote (about imprecise equipment) at face value; and (2) whether you are accusing Mead of being an intellectual fraud.
I did read the article, and looked at the sample pages from the book, and read another interesting speech [gilder.com] of Mead's, and think that it might be possible that there is a lot of merit in wanting to consider some particles - particularly electrons - as manifolds with boundary in stead of as singular points.
To deal with the first question, I think that Mead's main intent was to say that the Copenhagen Interpretation went wrong in insisting upon dogmatic adherence to the point particle model. He says that they understandably did not have access to the kind of data we do now, such as being able to see a single electron, but even more importantly, they had no experimental experience with coherent systems. Since their only experience was of incoherent systems, then of necessity, statistical models were all they could talk about. Mead is saying that with mounting evidence of coherent systems such as Lasers, Masers, Bose-Einstein condensates, etc. (he lists 10 in his book), that it appears to him that this is an even more important litmus test for understanding properties of "pure particles" (my paltry words here) than something like the Heisenberg Uncertainty Criterion.
The other thing I think Mead is addressing are logical paradoxes, which like you also mention, we all know must be created by lesser minds misapplying theoretical concepts. But like you, I feel unqualified to talk about these in physics at present. My gut feeling, however, is that dogmatism has been poisoning academic physics for decades.
Finally, our thread root poster, Elby, mentioned a "growing school" of thought. The article quotes Mead as follows:
Does anybody here know what the numbers of scientists, Real or not, are, who are publishing articles similar to Cramer's [washington.edu] in peer-reviewed journals?Well, that's my quick summary. I'd be curious to know what a "Real" scientist thought about Mead's perspective; I found it very interesting. [Disclaimer: I am not a scientist although I have a fair background in graduate mathematics and a bit as well in undergrad physics. But,] In fact, I have enough experience [wolfram.com] with math to have a certain skepticism about the wisdom of unthinkingly applying things as basic as the real number field, with its Archimedean property, or the idea of a mathematical point, with unqualified enthusiasm to great unknowns such as the elementary particles of nature. And for criticizing such an unthinking approach to matter, I would like to know if I am truly justified in applauding Mead (i.e. in the name of Real science).
In any case, I would be grateful to be educated out of any of my own misconceptions. Best of luck to you in producing Real science - I hope I get to read about the results some day!
Wanted... (Score:3, Funny)
Wanted:
DEAD and ALIVE
To clarify (Score:3, Informative)
Hall and Reginatto's paper does not supersede Heisenberg's uncertainty principle, nor does their paper change or challenge any of the fundamental results of quantum mechanics.
To explain:
Heisenberg's relation can be seen as an example of a (classical) result in Fourier theory about pairs of variables which are Fourier transforms of each other (for example time <> frequency), sometimes known as the bandwidth theorem. This is relevant because quantum wave mechanics asserts that wavefunction for a particle's momentum is essentially [a Constant times] the Fourier transform of the wavefunction of the particle's position.
Why should there be this Fourier relationship between x and p ? (After all, in classical physics both position and momentum are point quantites, assumed to exist independently to infinite precision.) Well typically, the position taken is either that you've drawn a picture of some waves wiggling along according to the Schrodinger equation, and you say you believe in your picture; or it's because you're stating the relation as an axiomatic principle, [\hat{x},\hat{p}] = ih/2pi, which with some other axioms you then use to derive Schrodinger's equation.
What Hall and Reginatto are really interested in is this: what other questions could you have set up, that would have led to the Schrodinger equation as a solution. (In statistics this approach is sometimes known as 'characterisation' of a distribution or evolution equation -- what "principles" might have caused it to come about).
Here they show that the Schrodinger equation and the x <> p Fourier transform relationship are in some senses the most 'natural' outcome, if you start with the classical Lagrangian of the Hamilton-Jacobi equation for the evolution of a probability distribution of a particle, and add a new term which adds an extra uncertainty to the momentum at each possible point, proportional to the local Fisher information of the probability distribution for position (ie its local sharpness, more or less).
This equation for an evolving probability distribution does not (necessarily) involve wavefunctions as physical entities; which may or may not make it a more useful and focussed way to think about what makes quantum mechanics "different".
The authors caution that their approach does not attempt to provide a 'realistic' [ie mechanistic] model for where the extra momentum uncertainty comes from; any such attempt, they write, 'would require a whole new (and nonlocal) theory that goes beyond quantum mechanics'.
Uncertainty? (Score:2, Funny)