First Plasma on the Levitated Dipole Experiment 447
deglr6328 writes "In light of recent, somewhat disappointing news in the world of nuclear fusion research, it is worth noting that there are still reasons to keep up hope that some breakthroughs are yet to be made. At 12:53 pm on the 13th. of this month the Levitated Dipole Experiment achieved its first plasma. The Levitated Dipole Experiment(LDX), built at MIT's Plasma Science and Fusion Center as a joint project of Columbia University and MIT, is a magnetic confinement fusion research device, that unlike all previous stellarator, reverse-field pinch and tokamak like experiments, uses a superconducting levitated torus to confine its plasma. The LDX's achievement of first plasma is, in a way, about 17 years in the making even though it has only been in construction since 1999. The concept for LDX was first considered by Akira Hasegawa as he was studying the data coming in from the Voyager missions which flew through the (dipole) magnetospheres of the outer planets. He noticed that unlike laboratory confined fusion plasmas which tended to be unstable, difficult to control, and which lost energy quickly, the plasma of a magnetosphere is intrinsically more quiescent, stable and actually reacts favorably (increases its density/temperature) to outside perturbations such as ie. bombardment by a solar storm. A highly informative and interesting video of operations on the day of first shot can be found here. Congratulations to the scientists and engineers who have worked very hard on getting the project to this point and here's looking forward to the possibility that LDX will reveal fundamentally new physics in the arduous quest for clean fusion energy."
If the cold-fusion people got even 1% of the money (Score:2, Interesting)
If even 1% of that money were spent on cold fusion research, we would probably be having much more interesting results by now. The great physicist Richard Feynman once said that he didn't see any theoretical reason why cold fusion would not work.
Re:If the cold-fusion people got even 1% of the mo (Score:2, Interesting)
Re:If the cold-fusion people got even 1% of the mo (Score:3, Interesting)
WOOO I'M THE INVISIBLE MAN (on certain time scales)
Still not doing Fusion the right way... (Score:3, Interesting)
The only clear way to do this is via Focus Fusion, which means one is working with the natural instabilities of Plasma rather than attempting to straightjacket them with massive Magnetic Fields. Nothing more really needs to be said about Focus Fusion from me so I'll just paste what they're saying here [focusfusion.org]:
Focus fusion is the only known method that can achieve hydrogen-boron fusion. It also has other advantages over tokamak based deuterium-tritium fusion reactors. Focus fusion reactors will be much less expensive for the same amount of power. Tokamak reactors generate electricity by boiling water for a steam powered generator (high energy neutrons provide the heat.) This is the same method that coal power plants use. The only difference is the heat source. In a coal power plant the steam generator is the most expensive part of the plant so replacing the heat source will not result in a lot of savings. Also, this method of generating electricity is limited by the fundamental efficiency limits of heat engines. Focus fusion reactors do not require a heat engine. They generate electricity directly. After all, electricity is just moving charged particles. The particle decelerators in a focus fusion reactor merely transfer the electricity of charged particle beams into a wire. This process does not face the efficiency limits of heat engines.
A focus fusion reactor should be able to economically generate power in quantities as small as 20MW from a power plant the size of a two car garage. This means they will be useful for powering individual villages in the third world where regional electricity grids are not as well developed. And in developed nations focus fusion power can be generated near where it will be used to reduce transmission losses and can be owned by the communities it serves to reduce dependence on speculative energy markets.
If there are any financiers out there who have the backbone to do what is right in this world and do what is right for mankind, I urge you to fund this research to banish forever the specter of Fossil Fuel shortages and associated ecological damage and begin a new era in Human History.
Re:If the cold-fusion people got even 1% of the mo (Score:4, Interesting)
No we wouldn't. Nobody is going to throw money at trying to do in practice something which doesn't work in theory. There is no theoretical model considered valid in which cold fusion works.
Paper and pencils don't cost much. Show the world a reasonable calculation proving from physics as we know it, that this is possible, and you can bet they'll get money.
The great physicist Richard Feynman once said that he didn't see any theoretical reason why cold fusion would not work.
Do you have a source for that? Besides which, that isn't relevant. There is a huge difference between showing something is possible and showing that it is not impossible.
Feynman himself also made a lot of good statements about pseudoscience. Perhaps you should read them? Unlike you, I provide a reference [brocku.ca].
My grad school room mate worked on this (Score:2, Interesting)
Makes one wonder if his thesis will be invoked at some point in this new endeavor.
Meanwhile I was working on chronological developments in Biblical Hebrews and their applicability to dating disputed texts in the Pentateuch. Reeeeeeeal useful stuff.
Re:No matter.. (Score:2, Interesting)
OMG, don't they believe in Darwinism? The birds that learn to fly around the windmills will breed and the others won't, problems solved. Better than all the birds of one species dying of climate change you would think. Maybe they secretly believe in creationism.
Maybe I don't have all my facts straight and I'm overreacting, but I would think GreenPeace to be in favor of dotting the landscape of every windy spot in the world with windmill generators. Every roof of the world cladded with (net energy gain) solar panels.
I can't see how Greenpeace can be against fusion but, like GreenPeace I'm unsure about nuclear fission, you gain energy by taking a huge deadly risk. That and the possibility of a country, let's say America, shooting the nuclear waste into the desert of countries they invade (hey, 2 problems solved at the same time, what's a few deformed babies for millennia gonna matter?)
Back on topic, Let's hope nuclear fusion works within a reasonable timeframe, it could save the world. I know of 3 approaches, the one in the story, the "traditional" tokamak containment field and the one where they shoot pellets of Deuterium with multiple lasers simultaneously. Which is the most promising?
Re:If the cold-fusion people got even 1% of the mo (Score:4, Interesting)
Well then you're going to have to explain to me why you don't think the laws of physics "as we know it" is a sufficient model for fusion. It certainly has provided us with relatively good models of the Sun, as well as predicted the Hydrogen bomb, and it also has shown to work with tokomak fusion.
Newtonian physics did not correctly predict the orbit of Mercury. There was no real reason to assume it should.
However, Newtonian physics did correctly predict,for instance, the motion of billard balls.
Now say someone walks along and says billard balls don't work at all in the way Newtonian physics says they do. Yet noone is able to make the billard balls act that way. Would that grounds for abandoning Newtonian physics as a model of billard balls? Abandon for what?
There is no alternative theory which allows cold fusion. If there was, people would be testing it.
In the same way that physics "as we know it" 150 years ago provided an accurate model for billiard balls, we have every reason to believe physics "as we know it" today provides an accurate model for fusion.
It is not the final model and it is probably not an accurate model for say, the inside of black holes and for sub-subatomic particles and the large-scale forces in the universe.
Re:how depressing (Score:2, Interesting)
What people need to realizing is that you learn a lot more by being wrong than you do by being right, but I suppose if somebody put the science propaganda back on TV (Kennedy, Sputnik, Cold War, et cetera) people would be much more (sheepishly) excited. It really doesn't help that instead of being at "war" with a scientific rival, we're fighting cavemen with US-made automatic weapons. Instead of being excited about a scientific arms race, we're excited about an eminent police state, and all I have to say is "God help the US, I'm moving to Japan."
Re:energy (Score:3, Interesting)
E.g. Global warming not caused by so-called greenhouse gases, but by waste heat generated by inefficient energy (esp. electricity) utilization..
Every day or two, the earth receives as much thermal energy from the sun as humans have harnessed in all of history. Any conceivable waste heat generated by humans would be an insignificant drop in the bucket.
Where we do have a measurable affect on the earth's temperature is changing the reflectivity of the ground so that the earth absorbs more of the massive solar influx, adding pollution to the atmosphere to change its transparency and cloud cover, and adding greenhouse gasses which slow the radiation of solar energy back to outer space. All of these effects work by throttling the balance between the unimaginably large amounts of solar energy that arrive and depart from the planet each day. Our puny addition of waste heat is lost in the noise.
Re:how depressing (Score:3, Interesting)
Don't feel too bad. Most Slashdotters are out on the town on a Saturday night; it's just the losers who are still posting. As for the moderators - no-one understands how it ends up being what it is, but the leading theory is that most moderators are under the influence of some pretty serious drugs while moderating.
Seriously though, congratulations on first plasma. I visited LDX about 8 months ago and you've certainly made much progress since then. However, you might want to make it clear that this doesn't mean that fusion is just around the corner. As far as I understand, the LDX concept is a bit of a dark horse; keeping the superconducting magnet cold in the presence of the plasma is challenging, no? I know they talk about a refrigerator, but that has never been demonstrated...
Anyway, I look forward to hearing about the plasma properties and confinement...
Re:If the cold-fusion people got even 1% of the mo (Score:2, Interesting)
As for tachyons, I believe thats more of a relativistic 'missing object', and one where you basically say 'hey, what does it imply if I pick a mass/energy as having this strange value...' as opposed to something demanded by the theory which simply hasn't been observed. The 'search for the Higgs boson' thing might be a better case, but then, if we don't find it even though we're looking where it should be found, we have to conclude that the theory that implies it is wrong, not that it exists but we're just unable to measure it.
Abundant clean energy as a bad thing? (Score:3, Interesting)
His problem was not with the energy source itself, but with what he thought it would be put to use doing. His preference was to limit what mankind could do with it by going for only relatively limited sources of power.
I strongly disagree with him, as you could make the same point about advanced medicine leading to biowar agents. Giving up what we've learned about antibiotics and containing epidemics because that information can be (and has been) misused seems misguided to me.
But, there certainly are people who feel that way.
There are larger numbers who are willing to accept the existing level of technology, but are very nervous about further discoveries.
Again, I personally feel this is misguided. We've largely made our Faustian bargain with technology, and going back or stagnating now would lead to truly massive suffering when the current pyramid game of our fuel sources run out.
I see more advanced power sources as a possible way for the masses of the third world to raise their standard of living greatly without the massive environmental impact that more primitive power sources would bring. We can argue about what sources to use (any of several might work), but trying to bring China and India to even a fraction of the per capita energy availability of the west with coal, for example, will have a huge impact.
Re:*sigh* (Score:2, Interesting)
You can read up on the Farnsworth Fusor [farnovision.com] to find out about a real Fusion device that operates at normal temperatures (of course there is a plasma generated that is very hot, but very small).
The theory behind cold fusion (Not that I am convinced) is that the Platinum can store up to 97%(?) of its weight in hydrogen, and that the hydrogen atoms in this matrix, under enough density have local energies high enough for fusion.
Plasmak (tm) (Score:2, Interesting)
The trademarking really makes it look like questionable science.
Re:*sigh* (Score:2, Interesting)
The Fusor article is actually very interesting. What I am wondering about is why exactly had the project been killed - apparently, it has been a success? Can anyone more physics-savvy than me comment on how reasonable such a device is as a fusion reactor? Of course, it is real hot fusion of a macroscopic scale in this case...
As for platinum, this "high density" idea is exactly the shortcoming of the infamous cold fusion paper. The problem with it is that you can't "heat" things up nearly enough through ordinary chemical interactions. Even absorbed in platinum, the internuclear distance of a D2 molecule won't change much (though the bond might break and some hairy scary Pt hydride may form). The kind of density you need to start fusion is the one you may achieve by, say, exploding the conventional fission device around your piece of Pt hydride - and that has been tried before by various governments :-)
By the way, similar ways to store hydrogen (as transition metal hydrides/adducts) are being successfully explored for fuel cell cars, and I don't think they are concerned about fusion.