I read this a day or two ago, and wondered to myself, "Whoever said that it had to be symmetrical?"
If you look at many structures in the universe, there are quite a few that are not spherically symmetrical. So either, we're in an asymmetrical blob, or there's just a more complex symmetry present. This should come as no surprise to the astronomy community, IMHO.
It is interesting, I think. It may give insight into our local neighbourhood.
Sorry if this sounds ignorant... but I have a fairly good grasp of the kind of physics that would be required in a game... for example in Quake or something like that. That said, here's my question:
I am a computational physicist... I write code (usually parallel, using MPI, for speed) that is obviously very physics intense. What the code amounts to is calculating forces between fluid elements and integrating Newton's 2nd law for them. Do these new Physics co-processors offer anything such that I could improve performance in my simulations? I flat out don't know. Anybody?
At any rate, however up to date he is with physics, he clearly doesn't know a damn thing about what's cutting edge in biology and he doesn't even mention any other science.
If you read his book, he does talk about the other sciences -- for what it's worth. In the end though, it's all physics anyway.:)
What exactly do you think religion should cover? The attitude of seperation is exactly the attitude that allowed Intelligent Design in the door in the first place. The fundamental attitude of ID is that everything that Biology can't adequately explain, probably can't be explained and just is because that is the way God made it. It puts a big stop sign up at the edge of current scientific understanding and tells us to look no further because that is just the way God made it and it is beyond our human comprehension.
My opinion (and others' too) is that science deals with the how -- religion deals with the why. For example, science can address easily HOW humans evolved and to a first approximation, HOW life came to be on Earth. However, WHY humans evolved? Well... nobody knows why. And science will never be able to definitively answer that. Same with WHY the Universe was created. There's just no answer to that.
Yes -- I grant that there are a few (small, in my opinion) holes in that viewpoint. But I think it's a reasonable benchmark.
OK, can anyone point to a single line in that interview that suggests this guy knows anything that qualifies him to hold forth on "the future of science"? He seems to have a strong layman's familiarity with current work in physics, a high school student's background in any other science and a lot of pompous namedropping about the novels he's read.
Sure. He has a B.Sc. in Physics from Princeton, a Ph.D. in Physics from Caltech... his thesis advisor there was Kip Thorne... and is good friends with many of the big names in science (for example, Gell-Mann... the quark guy). I'm sure he has a much stronger familiarity with physics than a layman. You'd be surprised what being in those circles does for one's perspective on science and its direction.:)
Mike.
Nice guy. Living in Memphis and all, I had the chance to meet him a few months back. He gave a lecture mirroring his new book (The Discoveries -- good book, by the way. Has a physicists perspective on ground-breaking pubs, and then the original pubs themselves, mostly unabridged). Since I also live in Memphis, there is a lot of that bible-belt mentality here... Earth is only 6,000 years old, etc. Anyway... somebody asked a question at the end, obviously of a pro-Intelligent Design slant, trying to get him to comment on it. It's refreshing to hear his take on the absurdity... and I can only hope that since he has status outside of the science community as well as within that his comments will make people think. (Basically... his answer was science and religion address different questions. Don't try to mix them).
I skimmed over his paper briefly... looking at the images of the red cells and all of that. I noticed that in a few pictures, the cells resemble red blood cells. Perhaps the meteor smashed into a flock of birds? Hah.
As far as I know -- superfluidity among fermions isn't that new, either. Superfluidity among bosons made perfect sense, but at first superfluidity among fermions did not... but it was seen in He-3 (2 protons, 1 neutron -- fermion).
Superfluidity in He-4 (2 protons, 2 neutrons -- boson) can easily be explained using Bose-Einstein statistics and a bit of math. To non-physics geeks, it can be explained roughly as the entire system residing in the same ground state, since any number of bosons can occupy a state. He-3 is a fermion -- therefore, only 2 fermions per state are allowed -- but has been known to exhibit superfluidity at low temperatures (though much lower than the Lambda-point for He-4 which is I think 2.5 K). The question was why He-3 is a superfluid, and the answer came in the form of Cooper pairs (like in superconductivity).
I guess I will have to make sure I can wield power like that before doing so however, I don't know what the policy usually is for asking students to leave classes at the university. (Though I do know that at my school, my fiancee is asked to leave quite often for coughing because the professor is a germaphobe. Heh.)
Don't know about where you are... but I am a lowly grad student teaching physics labs, and my department has told me time and time again that I have every right to kick a student out of class if they are causing a disruption. In fact, if they refuse to leave I can even call the university police to have them escourted from the class.
Decommissioned 3 GHz P4's!
Christ, I work for a major telecom company where they make software developers use 900 MHz PIII laptops.
Yeah, crazy isn't it? I couldn't believe it when I heard it. They update the hardware at the beginning of each fall semester in the student labs. Nice new flat screens, etc. Whatever the fastest-latest-greatest is that Dell offers. Then they distribute the "old" machines to faculty members, GAs, etc. I was lucky to get an entire lab's worth. I just wonder what kind of money they could be saving if they used machines longer... a 3 GHz machine could last years.
I inherited a bunch of 3 GHz P4 Optiplex machines back in '03 after they were decommissioned from a student computer lab. The university buys cheaper machines as they only keep them around in the labs for a year or so normally.
Well, I roped them together into a really nice Beowulf cluster for running my simulations and for the past 2 years I've had nodes die left and right. I'm sure the machines are out of warranty now, but I really hope Dell fixes these machines. I seem to remember Gateway doing this back in 2002. Now that the official word is out, maybe the computer department will take my word for it. What does a silly physicist know about computers and motherboards anyway?
Probably, but since encrypted hard drives usually involve a passphrase being converted into a key of suitable length by one-way hash algorithms, why not crack the passphrase instead of the actual key? Even with 256-bit AES (or something like it), a weak passphrase-based key is probably one of the easier ways to go after the data. Of course, if the suspect carries their completely random key around on a USB drive of some sort, that's a different matter.
I wish I could mod you up. Very true. This is something I've thought about. Let's say I'm using GPG or something like that. If the Feds come after my files and I've got my secret key lying around on my computer, or even somewhere easy to find, I think it'd be much easier just to crack the passphrase -- because really, there are common things a lot of people do for passwords. Replacing letters by numbers, adding #, !, @, alternating upper-lower case, etc. In the end, for most people, the password is something that is easy to remember, because if it's not, you're either going to have to have a great memory, or write it down somewhere. With this in mind, wouldn't cracking the passphrase be feasible in a smaller amount of time than if it were just brute forced? I honestly don't know -- I'm largely ignorant in that area, but it intrigues me nonetheless.
(I am aware, for the record, that brute forcing a password of any real length... e.g. even 6 or 7 chars long... requires an extraordinary amount of combinations of letters, numbers, and symbols... but if we can group those combinations into smaller units, don't we reduce the number?)
My understanding of it, and perhaps I am wrong, but I don't think so this time, is that the m in E=mc^2 is precisely what we all think of it as -- rest mass. The mass of a bowling ball, for example.
The contribution from motion, that you are referring to, is contained in the second term of the [full] relation:
E^2 = (mc^2)^2 + (pc)^2, where p is simply the momentum of the object.
As my Quantum Chemistry professor once said: "Trigonometry is just two formulas: cos^2(x)+sin^2(x)=1 and exp(ix)=cos(x)+i*sin(x). I don't know how they can blow it up into an entire 16 week course"
What you say is very true. I am working towards my Ph.D. right now in Physics, and I encounter this every day.
I think both you and the poster hit on something very important here. First is that we (as people who are reading the research papers) are not looking for proof, etc. of something. When I grab the latest paper on a topic I work on, I am not going to read it and say, "Oh. They found x which contradicts with what I am seeing. They must be right." Instead, I am looking at their models, results, and the like to see what HAS been done, what the outcome was, and if they have any problems. That way, I can address these issues in papers I write and talks I give. It also gives me something to compare my results to.
Your cousin is facing what I am facing, as well. I think people in the community understand perfectly well where she is -- that she has found interesting results thus far and needs to work more on it to get deeper understanding/whatever. To the outside world though... "it's just a theory" or "it's just preliminary" (phrases people love to throw around) drowns out the important stuff she's doing.
The second thing, that you specifically hit on, is that we need to eliminate options when we're working in an area. The pressure to produce sexy, nightly-news-ready results keeps us from doing that. Of course, I'm biased. Hah.
This doesn't mean all of this work has been pointless. People do studies, report their results (which are sometimes wrong)... but we know what we're doing, and we know what to take with a grain of salt and what not do.
Flash memory is going to do wonders for both battery life and size. Maybe I'll buy one of the new iPod minis if the rumors are true
Absolutely -- but I just have to wonder why they'd want to move the mini to flash. Battery life -- sure. But size? Wouldn't they just end up with an iPod shuffle with a screen? Maybe they're just going to discontinue the 4 gb mini and introduce a 4 gb shuffle (since the largest mini is currently 6 gb). Who knows...;)
This way your 13 year old neighbor will have to deal with encyption, MAC address cloning, and IP spoofing to get into your network. No doubt he will leave you alone and just use his other neighbor's open network.
My thoughts exactly. While these measures CAN be compromised with a lot of effort, most people will move on to the unprotected network unless they're in it for the challenge of getting on. I know before I paid for my broadband, I had MANY networks to choose from in my apt. building. If it had WEP, I would just leave it alone and use the unprotected. I know I could have gotten in, but it just wasn't worth the effort for just checking my e-mail.
Obviously, all operating systems have their pros and cons -- this includes Linux, Windows, MacOS, and others. We've heard a lot over the last few years from press releases and interviews about what cons Microsoft sees in Linux and Open Source in general. What pros does Microsoft see in Linux?
But can a country deny entry to one of its own citizens? I can see US customs detaining US citizens for drug/weapon/not declaring duty offences, but actually denying an American citizen the right to enter their own country?
I think you'll find that a country can do whatever it pleases. Maybe not legally... but they can pretty much do whatever they want. If you're American, then PROVE it will be their response. I am a Canadian... and I wouldn't have been admitted to Canada when I drove back a few years ago if I hadn't have had my birth certificate on me (this was before I had a passport). They were very skeptical that I was Canadian. Probably stemmed from my US license plates and US address, but that's not the point.
I am still Canadian and was almost refused. But... I can't really see this as a bad thing, necessarily. Passports are handy.
IBMs Java Database and now this . . . if I didnt know better, Id say that theres something of an open source release conspiracy going on. ..
Damn. Wellll.....seeming how open source supports terrorists, and there seems to be an open source release conspiracy.... perhaps we should raise the terror alert level!
I don't know what NASA would do with this, but I know what our group would do with it.
We always need machines. You could give me 1024 machines and I'd still need more.
For example, I study fluids currently. I may simulate 4,000,000 particles and it may take 3 weeks for my simulation to finish. If I had 10240 nodes, it may only take a day. Or perhaps I could simulate MORE particles for longer. There are all sorts of advantages to having this many machines hooked up.
One thing I can tell you for sure is that there most likely will not be *1* job that uses all of these at once. There are probably several researchers that are using it simultaneously and have a slice of the machines. Press releases like this are often time misleading because usually the CPUs are split between several jobs and researchers and research groups and what not.
Not to steal NASA's thunder -- a cluster this big is impressive.
Slashdot Mirror
If you look at many structures in the universe, there are quite a few that are not spherically symmetrical. So either, we're in an asymmetrical blob, or there's just a more complex symmetry present. This should come as no surprise to the astronomy community, IMHO.
It is interesting, I think. It may give insight into our local neighbourhood.
Mike.
Wouldn't this cover any web-hosting service?
Or e-mail? Ha ha.
Mike.
Sorry if this sounds ignorant... but I have a fairly good grasp of the kind of physics that would be required in a game... for example in Quake or something like that. That said, here's my question:
... I write code (usually parallel, using MPI, for speed) that is obviously very physics intense. What the code amounts to is calculating forces between fluid elements and integrating Newton's 2nd law for them. Do these new Physics co-processors offer anything such that I could improve performance in my simulations? I flat out don't know. Anybody?
I am a computational physicist
Mike.
I've had my stuff replaced by Apple in the past (1st gen 15" Al PowerBook. Doh!). Basically it goes:
1) Get box from DHL
2) They receive laptop by the next day, fix it, and drop it off at DHL.
3) You get nice new laptop back.
Takes about 3 days total.
Mike.
If you read his book, he does talk about the other sciences -- for what it's worth. In the end though, it's all physics anyway. :)
Mike.
My opinion (and others' too) is that science deals with the how -- religion deals with the why. For example, science can address easily HOW humans evolved and to a first approximation, HOW life came to be on Earth. However, WHY humans evolved? Well... nobody knows why. And science will never be able to definitively answer that. Same with WHY the Universe was created. There's just no answer to that.
Yes -- I grant that there are a few (small, in my opinion) holes in that viewpoint. But I think it's a reasonable benchmark.
Mike.
Sure. He has a B.Sc. in Physics from Princeton, a Ph.D. in Physics from Caltech... his thesis advisor there was Kip Thorne... and is good friends with many of the big names in science (for example, Gell-Mann... the quark guy). I'm sure he has a much stronger familiarity with physics than a layman. You'd be surprised what being in those circles does for one's perspective on science and its direction. :)
Mike.
Nice guy. Living in Memphis and all, I had the chance to meet him a few months back. He gave a lecture mirroring his new book (The Discoveries -- good book, by the way. Has a physicists perspective on ground-breaking pubs, and then the original pubs themselves, mostly unabridged). Since I also live in Memphis, there is a lot of that bible-belt mentality here... Earth is only 6,000 years old, etc. Anyway... somebody asked a question at the end, obviously of a pro-Intelligent Design slant, trying to get him to comment on it. It's refreshing to hear his take on the absurdity... and I can only hope that since he has status outside of the science community as well as within that his comments will make people think. (Basically... his answer was science and religion address different questions. Don't try to mix them).
Mike.
These are not men!
Mike.
I skimmed over his paper briefly... looking at the images of the red cells and all of that. I noticed that in a few pictures, the cells resemble red blood cells. Perhaps the meteor smashed into a flock of birds? Hah.
Mike.
As far as I know -- superfluidity among fermions isn't that new, either. Superfluidity among bosons made perfect sense, but at first superfluidity among fermions did not... but it was seen in He-3 (2 protons, 1 neutron -- fermion).
Superfluidity in He-4 (2 protons, 2 neutrons -- boson) can easily be explained using Bose-Einstein statistics and a bit of math. To non-physics geeks, it can be explained roughly as the entire system residing in the same ground state, since any number of bosons can occupy a state. He-3 is a fermion -- therefore, only 2 fermions per state are allowed -- but has been known to exhibit superfluidity at low temperatures (though much lower than the Lambda-point for He-4 which is I think 2.5 K). The question was why He-3 is a superfluid, and the answer came in the form of Cooper pairs (like in superconductivity).
Mike.
Don't know about where you are ... but I am a lowly grad student teaching physics labs, and my department has told me time and time again that I have every right to kick a student out of class if they are causing a disruption. In fact, if they refuse to leave I can even call the university police to have them escourted from the class.
Mike.
Yeah, crazy isn't it? I couldn't believe it when I heard it. They update the hardware at the beginning of each fall semester in the student labs. Nice new flat screens, etc. Whatever the fastest-latest-greatest is that Dell offers. Then they distribute the "old" machines to faculty members, GAs, etc. I was lucky to get an entire lab's worth. I just wonder what kind of money they could be saving if they used machines longer... a 3 GHz machine could last years.
Mike.
I inherited a bunch of 3 GHz P4 Optiplex machines back in '03 after they were decommissioned from a student computer lab. The university buys cheaper machines as they only keep them around in the labs for a year or so normally.
Well, I roped them together into a really nice Beowulf cluster for running my simulations and for the past 2 years I've had nodes die left and right. I'm sure the machines are out of warranty now, but I really hope Dell fixes these machines. I seem to remember Gateway doing this back in 2002. Now that the official word is out, maybe the computer department will take my word for it. What does a silly physicist know about computers and motherboards anyway?
Mike.
I wish I could mod you up. Very true. This is something I've thought about. Let's say I'm using GPG or something like that. If the Feds come after my files and I've got my secret key lying around on my computer, or even somewhere easy to find, I think it'd be much easier just to crack the passphrase -- because really, there are common things a lot of people do for passwords. Replacing letters by numbers, adding #, !, @, alternating upper-lower case, etc. In the end, for most people, the password is something that is easy to remember, because if it's not, you're either going to have to have a great memory, or write it down somewhere. With this in mind, wouldn't cracking the passphrase be feasible in a smaller amount of time than if it were just brute forced? I honestly don't know -- I'm largely ignorant in that area, but it intrigues me nonetheless.
(I am aware, for the record, that brute forcing a password of any real length... e.g. even 6 or 7 chars long... requires an extraordinary amount of combinations of letters, numbers, and symbols... but if we can group those combinations into smaller units, don't we reduce the number?)
Mike.
My understanding of it, and perhaps I am wrong, but I don't think so this time, is that the m in E=mc^2 is precisely what we all think of it as -- rest mass. The mass of a bowling ball, for example.
The contribution from motion, that you are referring to, is contained in the second term of the [full] relation:
E^2 = (mc^2)^2 + (pc)^2, where p is simply the momentum of the object.
Mike.
I couldn't agree more.
What you say is very true. I am working towards my Ph.D. right now in Physics, and I encounter this every day.
I think both you and the poster hit on something very important here. First is that we (as people who are reading the research papers) are not looking for proof, etc. of something. When I grab the latest paper on a topic I work on, I am not going to read it and say, "Oh. They found x which contradicts with what I am seeing. They must be right." Instead, I am looking at their models, results, and the like to see what HAS been done, what the outcome was, and if they have any problems. That way, I can address these issues in papers I write and talks I give. It also gives me something to compare my results to.
Your cousin is facing what I am facing, as well. I think people in the community understand perfectly well where she is -- that she has found interesting results thus far and needs to work more on it to get deeper understanding/whatever. To the outside world though... "it's just a theory" or "it's just preliminary" (phrases people love to throw around) drowns out the important stuff she's doing.
The second thing, that you specifically hit on, is that we need to eliminate options when we're working in an area. The pressure to produce sexy, nightly-news-ready results keeps us from doing that. Of course, I'm biased. Hah.
This doesn't mean all of this work has been pointless. People do studies, report their results (which are sometimes wrong)... but we know what we're doing, and we know what to take with a grain of salt and what not do.
Mike.
Absolutely -- but I just have to wonder why they'd want to move the mini to flash. Battery life -- sure. But size? Wouldn't they just end up with an iPod shuffle with a screen? Maybe they're just going to discontinue the 4 gb mini and introduce a 4 gb shuffle (since the largest mini is currently 6 gb). Who knows... ;)
Mike.
My thoughts exactly. While these measures CAN be compromised with a lot of effort, most people will move on to the unprotected network unless they're in it for the challenge of getting on. I know before I paid for my broadband, I had MANY networks to choose from in my apt. building. If it had WEP, I would just leave it alone and use the unprotected. I know I could have gotten in, but it just wasn't worth the effort for just checking my e-mail.
Mike.
I think you'll find that a country can do whatever it pleases. Maybe not legally... but they can pretty much do whatever they want. If you're American, then PROVE it will be their response. I am a Canadian... and I wouldn't have been admitted to Canada when I drove back a few years ago if I hadn't have had my birth certificate on me (this was before I had a passport). They were very skeptical that I was Canadian. Probably stemmed from my US license plates and US address, but that's not the point.
I am still Canadian and was almost refused. But... I can't really see this as a bad thing, necessarily. Passports are handy.
Mike.
This is really off topic, but...having also taken an astrophysics class with that textbook -- let me offer my condolences. It was a TERRIBLE text!
Damn. Wellll.....seeming how open source supports terrorists, and there seems to be an open source release conspiracy.... perhaps we should raise the terror alert level!
Mike.
I don't know what NASA would do with this, but I know what our group would do with it.
We always need machines. You could give me 1024 machines and I'd still need more.
For example, I study fluids currently. I may simulate 4,000,000 particles and it may take 3 weeks for my simulation to finish. If I had 10240 nodes, it may only take a day. Or perhaps I could simulate MORE particles for longer. There are all sorts of advantages to having this many machines hooked up.
One thing I can tell you for sure is that there most likely will not be *1* job that uses all of these at once. There are probably several researchers that are using it simultaneously and have a slice of the machines. Press releases like this are often time misleading because usually the CPUs are split between several jobs and researchers and research groups and what not.
Not to steal NASA's thunder -- a cluster this big is impressive.
Mike.