As far as I know, this uses superconducting technology, as it's the only way to get the huge currents needed for the huge magnetic fields needed to levitate an entire train.
Because of the way that superconductors work, you can also use them as shielding of magnetic fields, because they expel magnetic fields from themselves, so that could be how it's done.
But helium-3 *can* behave like a Bose-Einstein condensate, as the helium nuclei can loosely bind together, forming bosons from the two fermions. Which is why we get superfluid helium-3 as well. Of course, that doesn't happen til about 100mK (or similar), so you're unlikely to find some superfluid helium 3 in your kitchen.
A liquid is when the atoms are all free to move with respect to each other - they can slip and slide over each other. So in a liquid it's the atoms that are moving.
The notion of a vacancy only really holds for a crystalline solid, because in that case there's a regular lattice. The vacancy is when you'd expect an atom, but there isn't one.
What these people are saying is that somehow these holes are free to move, even though they're in a solid where, in general, the atoms and therefore the holes are fixed in position. I don't know the theory behind it, but I assume it's possible, otherwise Nature would have been fairly unlikely to have published it.
This possible evidence for water was presented fairly recently too. Some people think that, instead of being water, it could just be flows of rocks etc (basically landslides) causing these gullies, rather than water. This new data look far more convincing to me though. The prospect of it being nitrogen is further limited by the fact that it's a pretty light molecule which would have mostly escaped from Mars's weaker gravitational field.
We could in theory be seeing the same point twice now and not realised it, as it's actually very difficult to tell: remember that if the light has traversed the universe and then landed on the other side again it's taken quite a long time, in which the galaxy/quasar will have evolved. It's a possible way to definitively say that our universe is a hypertorus, but not the easiest!
Hmmm, and which propulsion system would this be? I know that there's one that has been proposed that can get from the Earth to Mars in six weeks using a kind of fusion drive (New Scientist vol 177 issue 2379 - 25 January 2003, page 23 - sorry, don't have a URL unless you can acess the NS archive, in which case it's here). Even this is still at the drawing board however. I would be very surprised if we could get a craft that could get to Pluto in a year in nine years time, given there are no ideas on how we'd do it at the moment...
I'm not questioning that they collect data. They specifically state that they collect data, but they also specifically state that it's only aggregate data. *shrugs* Not saying I think it's right, but they do actually say that (hmph, possibly should have quoted it above) "We do not transmit or collect your browsing activity and do not store any information that records your browsing behavior."
But as I said, I don't know how legally binding these things are, and there's enough in there to account for all the stuff that was mentioned in the article. I particularly liked the bit where it says 'You acknowledge and agree that you shall not...attempt to disable the Licensed Software by any means or in any manner'.
We do not transmit or collect your browsing activity and do not store any information that records your browsing behavior. We only collect aggregate statistics about the URLs and search terms you enter. We do not build profiles of our users or attempt to correlate demographic or personal information.
Not that I'd necessarily trust them. But aren't these things supposed to be somewhat legally enforceable?
The weak force doesn't actually hold anything together.
The strong force holds the quarks in the nucleons together, and this also holds the nucleus together - as the nucleons get close to each other, they're able to "see" the quarks inside each other, and are attracted. The strong force is actually infinite range, but appears to be a limited range because quarks are always bound into colourless states, and the strong force works on colour charge.
The weak force mediates between various particle decays etc, the most well known of which is beta decay, where a neutron turns into a proton, electron (and an electron neutrino).
This formula isn't particularly one you need to test the validity for. It's just like saying that we want stars that are as close to the sun as possible, but putting that in mathematical language so that we can quantitatively compare the stars we're looking at. We obviously pick stars which are as similar to the sun as possible, because as far as we're concerned, they're the most likely to harbour intelligent life.
Now, if you really want an equation that involves handwaving, check out the Drake equation. It's useful, in that it lays out what the factors are which contribute to the number of potentially communicating civilisations are, but as soon as you try to quantify it, you run into all kinds of problems. Different places give very different answers.
Re:"unknown"? Light article...
on
Einstein Unveiled
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· Score: 3, Informative
Fourth, Einstein introduced some constant in the relativity's equations so that the universe is static, which was his deep belief.
This is the cosmological constant, which he later abandoned (I think because it was realised that the Universe is expanding - previously they didn't think it was). It's now thought that this constant, which is associated with the energy density of vacuum, is associated with the dark matter (the existence of which has recently been verified) which is slowing the expansion of the Universe.
His abandoning of this idea is often called his greatest mistake.
I thought it was sad that they put pictures of Gandalf the White in the trailers (at least in the UK they did). It does mean that some of the impact will be lost on those who haven't read the books...
I know this may be a completely different issue, but I'm at University in the UK. As a general rule, I'm not notified of important changes or issues via email (the only exception being that the library has just started issuing overdue notices by email). I don't use email to tell my lecturers that something will be late (or if I do, I see them in person about it as soon as possible). And when my friends don't get an instant response either to an email or IM, then they assume I'm not at my computer or even *shock* *horror* I have it turned off.
I can't speak for people who get huge volumes of email at work, but college students who are getting overwhelmed really just need to sort themselves out by unsubbing from a few mailing lists (if all that mail is personal mail then they really need to get a life outside of their computer) and getting their IM to *say* when they're not in the vicinity. I don't think I know anyone who has this kind of problem.
Long story short, the privately funded scientists finished much farther ahead of the government's scientists, simply because they had the incentive to succeed. The government's money was useless, because the private sector yielded completely superior results; the government didn't care about the money spent because they were only spending the people's money.
Actually, the results from the private sector weren't superior at all. The government funded scientists' results were much more detailed and thorough.
I don't see why logistically, royalties should be charged twice, once for broadcast, once for stream. Arn't they both played from the same programming scheduale? What's the rationale behind justifying an additional fee?
Maybe because when it's being streamed, it's available to a much wider audience than when it's just being broadcast to a specific geographic area?
The theory of evolution (macroevolution, species evolving into other species over millions of years) is clearly inconsistent with the Bible, which says that the Earth and everything on it was divinely created within six days, and there is no indication anywhere in the Bible that this was not intended to be taken literally.
Yet another disclaimer: I, too, am a Christian, who believes in the bible, goes to church, all that sort of thing. However, I find the concept of the earth being created in six days flat bizarre. Given the sun was only created on the fourth 'day', how do you judge how long each of those days was? Surely the sun and the rotation of the earth is what governs a 'day'?
Slashdot Mirror
As far as I know, this uses superconducting technology, as it's the only way to get the huge currents needed for the huge magnetic fields needed to levitate an entire train.
Because of the way that superconductors work, you can also use them as shielding of magnetic fields, because they expel magnetic fields from themselves, so that could be how it's done.
No, helium does turn into a crystalline solid, and people have known this for a while. And you only need 25atm for it to do so :-)
See my comment here for the solid/liquid thing.
But helium-3 *can* behave like a Bose-Einstein condensate, as the helium nuclei can loosely bind together, forming bosons from the two fermions. Which is why we get superfluid helium-3 as well. Of course, that doesn't happen til about 100mK (or similar), so you're unlikely to find some superfluid helium 3 in your kitchen.
A liquid is when the atoms are all free to move with respect to each other - they can slip and slide over each other. So in a liquid it's the atoms that are moving.
The notion of a vacancy only really holds for a crystalline solid, because in that case there's a regular lattice. The vacancy is when you'd expect an atom, but there isn't one.
What these people are saying is that somehow these holes are free to move, even though they're in a solid where, in general, the atoms and therefore the holes are fixed in position. I don't know the theory behind it, but I assume it's possible, otherwise Nature would have been fairly unlikely to have published it.
This possible evidence for water was presented fairly recently too. Some people think that, instead of being water, it could just be flows of rocks etc (basically landslides) causing these gullies, rather than water. This new data look far more convincing to me though. The prospect of it being nitrogen is further limited by the fact that it's a pretty light molecule which would have mostly escaped from Mars's weaker gravitational field.
We could in theory be seeing the same point twice now and not realised it, as it's actually very difficult to tell: remember that if the light has traversed the universe and then landed on the other side again it's taken quite a long time, in which the galaxy/quasar will have evolved. It's a possible way to definitively say that our universe is a hypertorus, but not the easiest!
Hmmm, and which propulsion system would this be? I know that there's one that has been proposed that can get from the Earth to Mars in six weeks using a kind of fusion drive (New Scientist vol 177 issue 2379 - 25 January 2003, page 23 - sorry, don't have a URL unless you can acess the NS archive, in which case it's here). Even this is still at the drawing board however. I would be very surprised if we could get a craft that could get to Pluto in a year in nine years time, given there are no ideas on how we'd do it at the moment...
I'm not questioning that they collect data. They specifically state that they collect data, but they also specifically state that it's only aggregate data. *shrugs* Not saying I think it's right, but they do actually say that (hmph, possibly should have quoted it above) "We do not transmit or collect your browsing activity and do not store any information that records your browsing behavior."
...attempt to disable the Licensed Software by any means or in any manner'.
But as I said, I don't know how legally binding these things are, and there's enough in there to account for all the stuff that was mentioned in the article. I particularly liked the bit where it says 'You acknowledge and agree that you shall not
Weeeeelll... from their T&Cs...
We do not transmit or collect your browsing activity and do not store any information that records your browsing behavior. We only collect aggregate statistics about the URLs and search terms you enter. We do not build profiles of our users or attempt to correlate demographic or personal information.
Not that I'd necessarily trust them. But aren't these things supposed to be somewhat legally enforceable?
Of course, even for those of us who *do* use different browsers, there are still programs which use IE as a browser automatically.
Also there was a story about 2 weeks ago, mentioning solar energy breakthrough using full-spectrum layering. Does anyone know anymore about this.
Have a look here. It even comes with references to papers (not that I've read them, but y'know).
The weak force doesn't actually hold anything together.
The strong force holds the quarks in the nucleons together, and this also holds the nucleus together - as the nucleons get close to each other, they're able to "see" the quarks inside each other, and are attracted. The strong force is actually infinite range, but appears to be a limited range because quarks are always bound into colourless states, and the strong force works on colour charge.
The weak force mediates between various particle decays etc, the most well known of which is beta decay, where a neutron turns into a proton, electron (and an electron neutrino).
This formula isn't particularly one you need to test the validity for. It's just like saying that we want stars that are as close to the sun as possible, but putting that in mathematical language so that we can quantitatively compare the stars we're looking at. We obviously pick stars which are as similar to the sun as possible, because as far as we're concerned, they're the most likely to harbour intelligent life.
Now, if you really want an equation that involves handwaving, check out the Drake equation. It's useful, in that it lays out what the factors are which contribute to the number of potentially communicating civilisations are, but as soon as you try to quantify it, you run into all kinds of problems. Different places give very different answers.
Fourth, Einstein introduced some constant in the relativity's equations so that the universe is static, which was his deep belief.
This is the cosmological constant, which he later abandoned (I think because it was realised that the Universe is expanding - previously they didn't think it was). It's now thought that this constant, which is associated with the energy density of vacuum, is associated with the dark matter (the existence of which has recently been verified) which is slowing the expansion of the Universe.
His abandoning of this idea is often called his greatest mistake.
I thought it was sad that they put pictures of Gandalf the White in the trailers (at least in the UK they did). It does mean that some of the impact will be lost on those who haven't read the books...
Trailers are evil and spoilery.
I know this may be a completely different issue, but I'm at University in the UK. As a general rule, I'm not notified of important changes or issues via email (the only exception being that the library has just started issuing overdue notices by email). I don't use email to tell my lecturers that something will be late (or if I do, I see them in person about it as soon as possible). And when my friends don't get an instant response either to an email or IM, then they assume I'm not at my computer or even *shock* *horror* I have it turned off.
I can't speak for people who get huge volumes of email at work, but college students who are getting overwhelmed really just need to sort themselves out by unsubbing from a few mailing lists (if all that mail is personal mail then they really need to get a life outside of their computer) and getting their IM to *say* when they're not in the vicinity. I don't think I know anyone who has this kind of problem.
Actually, the results from the private sector weren't superior at all. The government funded scientists' results were much more detailed and thorough.
Maybe because when it's being streamed, it's available to a much wider audience than when it's just being broadcast to a specific geographic area?
Just a thought.
The theory of evolution (macroevolution, species evolving into other species over millions of years) is clearly inconsistent with the Bible, which says that the Earth and everything on it was divinely created within six days, and there is no indication anywhere in the Bible that this was not intended to be taken literally.
Yet another disclaimer: I, too, am a Christian, who believes in the bible, goes to church, all that sort of thing. However, I find the concept of the earth being created in six days flat bizarre. Given the sun was only created on the fourth 'day', how do you judge how long each of those days was? Surely the sun and the rotation of the earth is what governs a 'day'?
Just a thought.
Dua