In my experience, there are two types of physicists: those that do long analysis calculations (a few GR people) and those that have a copy of Numerical Recipes on the non-dusty end of their bookshelf. As for Fortran, it's still in heavy use, and F90/95 have made it a powerful tool on clusters.
It's a bit silly, but the point is that the star is traveling at a (local) supersonic velocity, while bullets typically travel a bit below the (local) supersonic velocity. People are too hard on scientific journalism; it's bad, but not uniformly so.
From the image, it looks like a truckbed fell over during the course of unloading something (presumably a tank of nox). A forklift is still upright, so the explosion couldn't have been huge, deathly though it was. Hopefully this is just a relatively minor accident at a relatively popular company.
Hawking has certainly benefitted -- in terms of his popular appearance -- from ALS. It is quite reasonable to wonder whether his work is truly valuable. In the long term, I think that we'll see that he hasn't made any monumental contributions to astrophysics or theoretical mathematics that are comparable with Guth's idea of inflation or with the Atiyah-Singer index theorem. However, he has contributed numerous less profound ideas: black hole radiation, some singularity theorems (with Penrose), and some ideas about black hole entropy and cosmology. In Kuhn's picture of scientific progress, Hawking's work is more "puzzle solving" than it is a paradigm shift.
At the same time, Hawking's ideas have been interesting and novel during the entire length of his career. He's a brilliant man on the forefront of a fascinating subject. Even if his ideas are epoch-defining or accurate, they are always worth thinking about.
1) DWave circumvents the normal scientific way of presenting the thing to the peers first.
This is probably owing to their business model of angel investment rather than publicly-funded research. It looks like the shows on Tuesday and Thursday are designed to attract people who might be interested in solving specific problems rather than to demonstrate the technical side of things. This is probably the right direction for the company, but it's quite unfortunate for the community.
I think it's worth a mention that this particular approach will only work on a small subset of the problems to which QCs might eventually be applied. Other, more popular, research paths like ion traps should lead to more general QCs. In particular, D-wave's design cannot implement Shor's algorithm for factorization (a fact which seems lost on many of the other posters, parent excluded).
There seem to be a number of "go for it!" posts, so I'll suggest something different. I know a few people (in astrophysics) who signed on to a certain research institution in a sysadmin type role, but since these sorts of places are pretty free, they were able to pick up the science on the side and join in with active research groups on projects. Since the field is so computer-driven, there's a fair bit of crossover (both ways, incidentally). It is probably the fastest way to doing research, it won't commit you to a 5-year degree program, and it will play to your strengths. Good luck with it.
I think that there is a huge market for a low-end, pretty laptop. If Intel designs and markets it correctly, it will be the next "must-have" for college students. If the specs and price are right, I'd happily sit one on my parents' desk when replacement time comes around. I do my work on a desktop with a nice big monitor and I have a beat-up desktop at home: my laptop needs to give presentations, keep me in touch while travelling, and not break when airport security plays with it.
It's a solid idea, and as the above poster pointed out, a small apparatus is being deployed on the ISS. However, there are a few reasons why it would be hard to make it work on a large scale: 1. Hard to determine the identity of the "beam" particles 2. Very low event rate 3. The expense of these detectors is (largely) in the detectors, which are huge and heavy besides, so the prospect of jetting (say, ATLAS) into orbit is quite unappealing. 4. Bandwidth. The DAQ stuff I'm working on for ATLAS calls for some ridiculously speedy equipment. It would probably be hard to transmit the data earthside. I guess that what I am saying is that it's too much of a challenge, just yet. Maybe next generation.:)
Oh, and I should note too that people are doing some really sweet stuff with cosmic rays from terra firma. The Pierre Auger Observatory, for example. In fact, the field has a fascinating unresolved mystery: there is a quite-reasonable argument for an upper limit to the energy of cosmic rays, but there's been a number of detections of cosmic rays with energies much in excess of this value. It reminds me a bit of the solar neutrino problem, where a mix of astronomy, reasonable arguments, and particle physics led to a paradigm shift in the latter (the neutrino having a mass). Exciting times!
The link is to a story about a guy who reprogrammed an ATM to think it was dispensing 5s while it was actually dispensing 20s. I was able to find the default passwords and re-programming instructions (all in the owner's manual) on the net without much trouble. At least one owner didn't bother to change the default passwords. I wonder how many others failed to do so.
A friend in the local power industry told me about a cool way in which the location of a break in a high-voltage line can be determined fairly cheaply. They use the GPS system to synchronize an incredibly-accurate clock at each end of the line. When the line breaks, the drop in voltage travels along the line from the break to the terminals at the speed of light. The clocks are precise enough that, by looking at the relative times when the voltage drop reaches the terminals, they can determine where the break happed to an accuracy of less than a kilomete; namely, to within a tower or two.
Gravity and Electromagnetism are definitely quite different. One of the big differences is that there are negatively-charged particles but there does not seem to be any matter with negative mass. If you play with pith balls (postively-charged objects) in a vacuum, say, you can do all the stuff that gravity does by using the Colulomb force rather than Newtonian gravity.
In the example of the sun-screen, it is the presence of negative and positive charges together that allow the screen to effectively block photons. If you just had a tank of free protons in front of a lamp, the light would excite the protons, causing them to emit radiation in all directions, just like what happens in the gravity-screen picture.
The last thing is that, although gravitons carry the gravitational force, they are exchanged in most circumstances. So the earth sends the sun a graviton for every graviton the sun sends the earth. The same thing happens with photons in a hydrogen atom: the electron and nucleus exchange photons. Now, there is an analogy to free photons (light, etc) in the gravity picture: gravity waves. Gravity waves are similar to electromagnetic waves except that they have MUCH smaller amplitudes. These guys haven't been detected directly yet, but there's a lot of evidence for them and the experiments (LIGO, Hulse-Taylor, etc) have made all the right noises so far...
I would love to see Hawking's reply to String Theory.
I think that he's actually working *in* string theory, as far as it goes.
I have seen much discussion involving the "graviton", relating it to the photon. Apparently I can stop a photonic flux with a photonic shield ( aka "sunshade" )... anyone been able to shade matter from the "graviton flux" yet? I haven't seen it.
Can your subshade stop radio waves? X-rays? It's hard to say how gravitons work since no-one has ever seen one, but it's probably something similar to photons. Photons are associated with electric charge, gravitons with mass. Thus, gravitons would be blocked by an appropriately-large block of matter.
The parent is absolutely correct. Other examples of the "clean/slim" approach paying dividends: Facebook, Craigslist, Google's ads, I remember Ebay being slick and quick in its early days. I guess that some people are willing to wait 10 seconds for the Yahoo! portal to load, but I don't have that patience.
Hawking has been working in string theory lately. He gave a public lecture at the Strings 06 conference in China this past summer, and his recent-ish work on the entropy of black holes (reported here maybe last year) was done in the framework of string theory.
I should be careful, though: it's a pretty large field. By some reckonings strings are everything in theoretical high-energy physics *except* the theories that are explicitly not string theory (loop gravity, the field of recent Slashdot-ee Lee Smolin, Roger Penrose's twistors, various discretized spacetime theories, and so forth).
Check the last link in the summary. The author is a highly-respected mathematician in the field and this follows previous work that has been peer-reviewed. That doesn't mean it is *right*, but that does make it newsworthy.
Spot on, parent. It is impossible to appreciate the allure of the mathematical foundations without many years of dedicated study. It says a lot that two researchers have spoken out as they have, but I think that most of the community feels that the conceptual motivation for string theory is sufficient to warrant more investigation... and even their fellow physicists don't have the understanding to vouch for one side of this debate or the other.
It's also worth mentioning that this research -- at its worst -- is pushing the limits of several fields of mathematics. Ed Witten's Fields Medal gives evidence of that. (iaap)
Bradbury's future was marked by huge video screens in the living room, little speakers in the ears, people pursuing dangerous hobbies because their lives had become empty (street racing, in the novel), and a disinclination towards knowledge (books) in favour of a false sense of reality being fed to citizens through the media.
I don't want to sound like a braggart, but I averaged 21 credits per semester for the final three years of my BSc (majors in Physics, Maths, and Astronomy). In addition, I paid almost all of my tuition by working as a TA: two or three classes per semester for those same three years. I spent the summers doing research (no credit value).
And no, I didn't get laid. I got an awesome education, but I didn't get laid.
Slashdot Mirror
In my experience, there are two types of physicists: those that do long analysis calculations (a few GR people) and those that have a copy of Numerical Recipes on the non-dusty end of their bookshelf. As for Fortran, it's still in heavy use, and F90/95 have made it a powerful tool on clusters.
It's a bit silly, but the point is that the star is traveling at a (local) supersonic velocity, while bullets typically travel a bit below the (local) supersonic velocity. People are too hard on scientific journalism; it's bad, but not uniformly so.
From the image, it looks like a truckbed fell over during the course of unloading something (presumably a tank of nox). A forklift is still upright, so the explosion couldn't have been huge, deathly though it was. Hopefully this is just a relatively minor accident at a relatively popular company.
Homer Hickam, aerospace engineer at NASA from '81 to '98. You might remember him as the protagonist in the film "October Sky".
They should do what USA did in '06: threaten the populace with two more years of unbridled Bush.
Hawking has certainly benefitted -- in terms of his popular appearance -- from ALS. It is quite reasonable to wonder whether his work is truly valuable. In the long term, I think that we'll see that he hasn't made any monumental contributions to astrophysics or theoretical mathematics that are comparable with Guth's idea of inflation or with the Atiyah-Singer index theorem. However, he has contributed numerous less profound ideas: black hole radiation, some singularity theorems (with Penrose), and some ideas about black hole entropy and cosmology. In Kuhn's picture of scientific progress, Hawking's work is more "puzzle solving" than it is a paradigm shift.
At the same time, Hawking's ideas have been interesting and novel during the entire length of his career. He's a brilliant man on the forefront of a fascinating subject. Even if his ideas are epoch-defining or accurate, they are always worth thinking about.
A decrease in mass and an increase in luminosity will move a star in a direction perpendicular to the main sequence on the HR diagram.
Repeat after me: Stars DO NOT evolve along the main sequence. They do not. Please don't repeat this lie to anyone else.
This is probably owing to their business model of angel investment rather than publicly-funded research. It looks like the shows on Tuesday and Thursday are designed to attract people who might be interested in solving specific problems rather than to demonstrate the technical side of things. This is probably the right direction for the company, but it's quite unfortunate for the community.
I think it's worth a mention that this particular approach will only work on a small subset of the problems to which QCs might eventually be applied. Other, more popular, research paths like ion traps should lead to more general QCs. In particular, D-wave's design cannot implement Shor's algorithm for factorization (a fact which seems lost on many of the other posters, parent excluded).
There seem to be a number of "go for it!" posts, so I'll suggest something different. I know a few people (in astrophysics) who signed on to a certain research institution in a sysadmin type role, but since these sorts of places are pretty free, they were able to pick up the science on the side and join in with active research groups on projects. Since the field is so computer-driven, there's a fair bit of crossover (both ways, incidentally). It is probably the fastest way to doing research, it won't commit you to a 5-year degree program, and it will play to your strengths. Good luck with it.
http://arxiv.org/abs/hep-ph/0604255
I think that there is a huge market for a low-end, pretty laptop. If Intel designs and markets it correctly, it will be the next "must-have" for college students. If the specs and price are right, I'd happily sit one on my parents' desk when replacement time comes around. I do my work on a desktop with a nice big monitor and I have a beat-up desktop at home: my laptop needs to give presentations, keep me in touch while travelling, and not break when airport security plays with it.
But what I really want is a PADD.
It's a solid idea, and as the above poster pointed out, a small apparatus is being deployed on the ISS. However, there are a few reasons why it would be hard to make it work on a large scale: :)
1. Hard to determine the identity of the "beam" particles
2. Very low event rate
3. The expense of these detectors is (largely) in the detectors, which are huge and heavy besides, so the prospect of jetting (say, ATLAS) into orbit is quite unappealing.
4. Bandwidth. The DAQ stuff I'm working on for ATLAS calls for some ridiculously speedy equipment. It would probably be hard to transmit the data earthside.
I guess that what I am saying is that it's too much of a challenge, just yet. Maybe next generation.
Oh, and I should note too that people are doing some really sweet stuff with cosmic rays from terra firma. The Pierre Auger Observatory, for example. In fact, the field has a fascinating unresolved mystery: there is a quite-reasonable argument for an upper limit to the energy of cosmic rays, but there's been a number of detections of cosmic rays with energies much in excess of this value. It reminds me a bit of the solar neutrino problem, where a mix of astronomy, reasonable arguments, and particle physics led to a paradigm shift in the latter (the neutrino having a mass). Exciting times!
The link is to a story about a guy who reprogrammed an ATM to think it was dispensing 5s while it was actually dispensing 20s. I was able to find the default passwords and re-programming instructions (all in the owner's manual) on the net without much trouble. At least one owner didn't bother to change the default passwords. I wonder how many others failed to do so.
A friend in the local power industry told me about a cool way in which the location of a break in a high-voltage line can be determined fairly cheaply. They use the GPS system to synchronize an incredibly-accurate clock at each end of the line. When the line breaks, the drop in voltage travels along the line from the break to the terminals at the speed of light. The clocks are precise enough that, by looking at the relative times when the voltage drop reaches the terminals, they can determine where the break happed to an accuracy of less than a kilomete; namely, to within a tower or two.
Gravity and Electromagnetism are definitely quite different. One of the big differences is that there are negatively-charged particles but there does not seem to be any matter with negative mass. If you play with pith balls (postively-charged objects) in a vacuum, say, you can do all the stuff that gravity does by using the Colulomb force rather than Newtonian gravity.
In the example of the sun-screen, it is the presence of negative and positive charges together that allow the screen to effectively block photons. If you just had a tank of free protons in front of a lamp, the light would excite the protons, causing them to emit radiation in all directions, just like what happens in the gravity-screen picture.
The last thing is that, although gravitons carry the gravitational force, they are exchanged in most circumstances. So the earth sends the sun a graviton for every graviton the sun sends the earth. The same thing happens with photons in a hydrogen atom: the electron and nucleus exchange photons. Now, there is an analogy to free photons (light, etc) in the gravity picture: gravity waves. Gravity waves are similar to electromagnetic waves except that they have MUCH smaller amplitudes. These guys haven't been detected directly yet, but there's a lot of evidence for them and the experiments (LIGO, Hulse-Taylor, etc) have made all the right noises so far...
IF gravitons exist.
I think that he's actually working *in* string theory, as far as it goes.
Can your subshade stop radio waves? X-rays? It's hard to say how gravitons work since no-one has ever seen one, but it's probably something similar to photons. Photons are associated with electric charge, gravitons with mass. Thus, gravitons would be blocked by an appropriately-large block of matter.
The parent is absolutely correct. Other examples of the "clean/slim" approach paying dividends: Facebook, Craigslist, Google's ads, I remember Ebay being slick and quick in its early days. I guess that some people are willing to wait 10 seconds for the Yahoo! portal to load, but I don't have that patience.
Hawking has been working in string theory lately. He gave a public lecture at the Strings 06 conference in China this past summer, and his recent-ish work on the entropy of black holes (reported here maybe last year) was done in the framework of string theory.
I should be careful, though: it's a pretty large field. By some reckonings strings are everything in theoretical high-energy physics *except* the theories that are explicitly not string theory (loop gravity, the field of recent Slashdot-ee Lee Smolin, Roger Penrose's twistors, various discretized spacetime theories, and so forth).
Check the last link in the summary. The author is a highly-respected mathematician in the field and this follows previous work that has been peer-reviewed. That doesn't mean it is *right*, but that does make it newsworthy.
Spot on, parent. It is impossible to appreciate the allure of the mathematical foundations without many years of dedicated study. It says a lot that two researchers have spoken out as they have, but I think that most of the community feels that the conceptual motivation for string theory is sufficient to warrant more investigation... and even their fellow physicists don't have the understanding to vouch for one side of this debate or the other.
It's also worth mentioning that this research -- at its worst -- is pushing the limits of several fields of mathematics. Ed Witten's Fields Medal gives evidence of that. (iaap)
Bradbury's future was marked by huge video screens in the living room, little speakers in the ears, people pursuing dangerous hobbies because their lives had become empty (street racing, in the novel), and a disinclination towards knowledge (books) in favour of a false sense of reality being fed to citizens through the media.
Golly gee, I hope that's not our future.
I don't want to sound like a braggart, but I averaged 21 credits per semester for the final three years of my BSc (majors in Physics, Maths, and Astronomy). In addition, I paid almost all of my tuition by working as a TA: two or three classes per semester for those same three years. I spent the summers doing research (no credit value).
And no, I didn't get laid. I got an awesome education, but I didn't get laid.