What I don't quite get - and maybe someone can enlighten me - is how they keep 80K compute nodes going. Even with very reliable hardware, several of these nodes will fail each day. The massively parallel codes I work with (MD) can't deal with a compute node going out. Do other massively parallel codes have a way to deal with this sort of thing? This seems to be a big challenge for parallel computing. When you have a code and problem that can use several thousand nodes, hardware failure will be a daily occurrence. Incidentally, I've had the opportunity to use several thousand cpus in one go. Before New Mexico's Encanto was released for general use I was one of several people that had access to the machine. There really wasn't a problem running million or billion atom systems over several thousand cpus. But this was just brief benchmarking runs. Not data production.
I've killed, butchered, and cooked several animals. By far, the most difficult part is killing the animal. Especially when it doesn't go well. It can be pretty disturbing. All the rest is just gore. I wish more people had this attitude. I think fewer animals would live miserable lives and people would waste less.
"Yes, but position and momentum have quantum operators. Time has no operator. "
I don't "do" quantum mechanics regularly enough to be very familiar with the literature. But, this isn't what I was told in my graduate work. I haven't ever used it as such, but there is a formulation for a time operator conjugate to energy. A brief search turned up a current review.
"Time as a Quantum Observable, Canonically Conjugated to Energy, and Foundations of Self-Consistent Time Analysis of Quantum Processes" Advances in Mathematical Physics Volume 2009 (2009), Article ID 859710, 83 pages doi:10.1155/2009/859710
If you hit a pay wall I'd be happy to forward a pdf. Anyway, I don't think any of that is germane to my point. Which I'm sure you get, pedantry aside.
You are right. I meant "fundamental nature" as a sort of metaphysical description. We are talking about some "feature" of nature that has some consequences - Hawking radiation and the Casimir force, tunneling and reaction kinetics, and limits on measurement.
I suppose empiricism is a lot of science. But a lot of good has come from interpretations that presume to know about things and how they behave. Even if they are just placeholders. I'm a scientist. Every day I talk to other scientists about things - not measurements. As far as I know, it's how everybody goes about it. I don't have any reason to think otherwise.
The OP stated the uncertainty is a result of our inability to measure. But the inability to measure is a result of the uncertainty. The UP is a statement about the fundamental nature of quantum events, which has consequences for measurement. A subtle but significant difference.
To the second part - the UP has *nothing* to do with available states or ensembles.
I gave the example of the time/energy non-commuting operators specifically because it isn't as misleading as the position/momentum. You can experimentally alter the decay time, which changes the line width. But if you don't like that, consider vacuum energy. Matter isn't created because of your measurement. It is the result of the fundamental nature of space, which has consequences for your measurement. The OP stated the uncertainty is a result of our inability to measure. But the inability to measure is a result of the uncertainty. A subtle but significant difference.
"Like the uncertainty principle, all common thinking tells is is that the atom must have a definite position and velocity - but it doesn't because we can't measure it"
Wrong. You can't measure it because it doesn't. The UP isn't about your ability to measure something. Consider time/energy uncertainty. The faster an excited state decays, the broader the distribution in energies of emitted photons.
Maybe this is how you and your wife need to do things, but it's hardly a "cornerstone" of marriage. My wife and I have been together close to 14 years now, and don't do things that way. I regularly access her email – when balancing the checkbook I need to reconcile the statement against her emailed receipts. I don't look at other things, but I have no reason to. She would tell me anything of consequence. She has access to my email as well. Facebook account too. All our financial accounts are joint. We have power of attorney for each other. I can't imagine what I would hide from her that wouldn't be some marital transgression. I get that she needs personal space, but keeping secrets isn't part of that.
The CBO scoring that showed it wouldn't was contingent on cuts in Medicare that everyone knows wont be made – congress *just* put them off for another year. The CBO was so concerned about this obvious legislative trickery that they also included scoring for the law without the putative cuts. And it increases the debt. The president and congressional Democrats knew they had a problem with Medicare reimbursement for doctors in the original healthcare legislation. The solution was to split that portion of the legislation out (the so-called "doc fix"), and pass it separately. So a well informed person would likely be correct in answering that question affirmatively. In any event, we wont know the real cost until all the law is fully implemented. Congress can't even answer how many new agencies will be needed to oversee all the moving parts of this law. The cost is just as uncertain.
appearing on Different Strokes. Painfully lame. Politicians can't make science cool because kids don't think much of politicians. If they do, then I'm afraid you are likely preaching to the choir.
"And pointing out that the validity of a study is suspect because the publisher has a demonstrated history of self-interested bias in that area is not an ad hominem attack."
No, that's exactly the ad hominem logical fallacy. You question the credibility of the publisher in place of addressing the merits of the arguments made in the publication. I think you are making a common mistake. That is, that ad hominem is just about insulting someone. It's simply a specific way of reasoning – incorrectly - when making an argument.
As to the rest, it's really bizarre and off-putting. I don't know if it's intentional, or you are just odd, or pretending to be odd. But I'm done.
"The premise that over the long term preventive medicine is as costly as intervention after disease or injury has happened is not demonstrated, and is highly unlikely on the fac of it."
If by "not demonstrated" you mean "refuted with an ad hominem fallacy regarding JAMA's credibility", then yes. Point made. Brilliantly.
Preventative care does not cost less, overall. And consequently, there isn't less profit (remember, fee for service). Preventative care does improve outcome (and should be advocated for on that merit), but it does not reduce cost. Just before the national healthcare reform debate, a long tail study was published by JAMA that showed that people receiving preventative care lived longer, and ultimately cost as much as people who received only heroic care in their final days.
.. about Jon Stewart just being a comedian, too? Satire and humor are some of the oldest, well worn ways of political speech. Carlin was funny - and right.
Most publications are group work. Maybe the first author wrote the entire work without input, using only the results of others. And maybe every other author made significant changes or critiques. Those words can't be reused – unless they include every previous author in the new list. Reuse an introduction a few times and the author list is going to get pretty long. Anyway, it is copyright violation to use previously published phrases and images in a publication for a different publisher. That is clear.
I do molecular dynamics. These are MD simulations. They are talking 2 orders of magnitude speedup. That's good, but not good enough to compete with bench work. Incidentally, people are claiming this sort of speedup by offloading some parts of the calculation to a GPU. NCSA has a cluster of GPUs for just this use - Lincoln if I recall correctly. MD is currently useful for a lot of stuff. Not drug design yet.
I suppose that depends on what you are doing. The kinds of potential energy surfaces these simulations use are extremely crude - ball and spring (sometimes one ball for many atoms), electrostatics, short range repulsion, and no chemical reactions. Only good for rough trends in docking and stuff. If you need reactivity, and you will for it to really compete with bench work, there are some severely limited classical force fields that work - but they are at least an order of magnitude more expensive. More accurate methods (quantum mechanics) are multiple orders of magnitude more expensive.
This has been the promise of computer simulation - "in silico" drug design - for decades. It hasn't panned out. And I say this as someone who makes a living doing exactly what these folks have done. High throughput bench work is far more efficient, time and money wise, than computer simulation. Hard to say when or if that will change.
"As Libertarians, we seek a world of liberty; a world in which all individuals are sovereign over their own lives and no one is forced to sacrifice his or her values for the benefit of others."
They are established scientists with their own self interest. If a small number of referees can have a large effect, imagine what a small number of poor editors could do.
Slashdot Mirror
What I don't quite get - and maybe someone can enlighten me - is how they keep 80K compute nodes going. Even with very reliable hardware, several of these nodes will fail each day. The massively parallel codes I work with (MD) can't deal with a compute node going out. Do other massively parallel codes have a way to deal with this sort of thing? This seems to be a big challenge for parallel computing. When you have a code and problem that can use several thousand nodes, hardware failure will be a daily occurrence. Incidentally, I've had the opportunity to use several thousand cpus in one go. Before New Mexico's Encanto was released for general use I was one of several people that had access to the machine. There really wasn't a problem running million or billion atom systems over several thousand cpus. But this was just brief benchmarking runs. Not data production.
Most people have it. And I'm guessing you do to. Despite all the lame - and transparent - machismo bluster.
I've killed, butchered, and cooked several animals. By far, the most difficult part is killing the animal. Especially when it doesn't go well. It can be pretty disturbing. All the rest is just gore. I wish more people had this attitude. I think fewer animals would live miserable lives and people would waste less.
"Yes, but position and momentum have quantum operators. Time has no operator. "
I don't "do" quantum mechanics regularly enough to be very familiar with the literature. But, this isn't what I was told in my graduate work. I haven't ever used it as such, but there is a formulation for a time operator conjugate to energy. A brief search turned up a current review.
"Time as a Quantum Observable, Canonically Conjugated to Energy, and Foundations of Self-Consistent Time Analysis of Quantum Processes"
Advances in Mathematical Physics
Volume 2009 (2009), Article ID 859710, 83 pages
doi:10.1155/2009/859710
If you hit a pay wall I'd be happy to forward a pdf. Anyway, I don't think any of that is germane to my point. Which I'm sure you get, pedantry aside.
You are right. I meant "fundamental nature" as a sort of metaphysical description. We are talking about some "feature" of nature that has some consequences - Hawking radiation and the Casimir force, tunneling and reaction kinetics, and limits on measurement.
I suppose empiricism is a lot of science. But a lot of good has come from interpretations that presume to know about things and how they behave. Even if they are just placeholders. I'm a scientist. Every day I talk to other scientists about things - not measurements. As far as I know, it's how everybody goes about it. I don't have any reason to think otherwise.
The OP stated the uncertainty is a result of our inability to measure. But the inability to measure is a result of the uncertainty. The UP is a statement about the fundamental nature of quantum events, which has consequences for measurement. A subtle but significant difference.
To the second part - the UP has *nothing* to do with available states or ensembles.
I gave the example of the time/energy non-commuting operators specifically because it isn't as misleading as the position/momentum. You can experimentally alter the decay time, which changes the line width. But if you don't like that, consider vacuum energy. Matter isn't created because of your measurement. It is the result of the fundamental nature of space, which has consequences for your measurement. The OP stated the uncertainty is a result of our inability to measure. But the inability to measure is a result of the uncertainty. A subtle but significant difference.
"Like the uncertainty principle, all common thinking tells is is that the atom must have a definite position and velocity - but it doesn't because we can't measure it"
Wrong. You can't measure it because it doesn't. The UP isn't about your ability to measure something. Consider time/energy uncertainty. The faster an excited state decays, the broader the distribution in energies of emitted photons.
Maybe this is how you and your wife need to do things, but it's hardly a "cornerstone" of marriage. My wife and I have been together close to 14 years now, and don't do things that way. I regularly access her email – when balancing the checkbook I need to reconcile the statement against her emailed receipts. I don't look at other things, but I have no reason to. She would tell me anything of consequence. She has access to my email as well. Facebook account too. All our financial accounts are joint. We have power of attorney for each other. I can't imagine what I would hide from her that wouldn't be some marital transgression. I get that she needs personal space, but keeping secrets isn't part of that.
just checked. BS Chemistry, BS Mathematics.
Start here.
http://reason.com/archives/2010/12/21/how-to-record-the-cops
The CBO scoring that showed it wouldn't was contingent on cuts in Medicare that everyone knows wont be made – congress *just* put them off for another year. The CBO was so concerned about this obvious legislative trickery that they also included scoring for the law without the putative cuts. And it increases the debt. The president and congressional Democrats knew they had a problem with Medicare reimbursement for doctors in the original healthcare legislation. The solution was to split that portion of the legislation out (the so-called "doc fix"), and pass it separately. So a well informed person would likely be correct in answering that question affirmatively. In any event, we wont know the real cost until all the law is fully implemented. Congress can't even answer how many new agencies will be needed to oversee all the moving parts of this law. The cost is just as uncertain.
appearing on Different Strokes. Painfully lame. Politicians can't make science cool because kids don't think much of politicians. If they do, then I'm afraid you are likely preaching to the choir.
"And pointing out that the validity of a study is suspect because the publisher has a demonstrated history of self-interested bias in that area is not an ad hominem attack."
No, that's exactly the ad hominem logical fallacy. You question the credibility of the publisher in place of addressing the merits of the arguments made in the publication. I think you are making a common mistake. That is, that ad hominem is just about insulting someone. It's simply a specific way of reasoning – incorrectly - when making an argument.
As to the rest, it's really bizarre and off-putting. I don't know if it's intentional, or you are just odd, or pretending to be odd. But I'm done.
"The premise that over the long term preventive medicine is as costly as intervention after disease or injury has happened is not demonstrated, and is highly unlikely on the fac of it."
If by "not demonstrated" you mean "refuted with an ad hominem fallacy regarding JAMA's credibility", then yes. Point made. Brilliantly.
Preventative care does not cost less, overall. And consequently, there isn't less profit (remember, fee for service). Preventative care does improve outcome (and should be advocated for on that merit), but it does not reduce cost. Just before the national healthcare reform debate, a long tail study was published by JAMA that showed that people receiving preventative care lived longer, and ultimately cost as much as people who received only heroic care in their final days.
Most publications are group work. Maybe the first author wrote the entire work without input, using only the results of others. And maybe every other author made significant changes or critiques. Those words can't be reused – unless they include every previous author in the new list. Reuse an introduction a few times and the author list is going to get pretty long. Anyway, it is copyright violation to use previously published phrases and images in a publication for a different publisher. That is clear.
like i said
an 33 order of magnitude increase in a single typical MD timestep is of the order of the lifetime of the universe.
I do molecular dynamics. These are MD simulations. They are talking 2 orders of magnitude speedup. That's good, but not good enough to compete with bench work. Incidentally, people are claiming this sort of speedup by offloading some parts of the calculation to a GPU. NCSA has a cluster of GPUs for just this use - Lincoln if I recall correctly. MD is currently useful for a lot of stuff. Not drug design yet.
I suppose that depends on what you are doing. The kinds of potential energy surfaces these simulations use are extremely crude - ball and spring (sometimes one ball for many atoms), electrostatics, short range repulsion, and no chemical reactions. Only good for rough trends in docking and stuff. If you need reactivity, and you will for it to really compete with bench work, there are some severely limited classical force fields that work - but they are at least an order of magnitude more expensive. More accurate methods (quantum mechanics) are multiple orders of magnitude more expensive.
This has been the promise of computer simulation - "in silico" drug design - for decades. It hasn't panned out. And I say this as someone who makes a living doing exactly what these folks have done. High throughput bench work is far more efficient, time and money wise, than computer simulation. Hard to say when or if that will change.
The start of the LP platform -
"As Libertarians, we seek a world of liberty; a world in which all individuals are sovereign over their own lives and no one is forced to sacrifice his or her values for the benefit of others."
And how do kings and nobels fit in?
Dumbass.
They are established scientists with their own self interest. If a small number of referees can have a large effect, imagine what a small number of poor editors could do.