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Ultra-Dense Deuterium Produced
Omomyid was among several readers writing in about the production of microscopic amounts of ultra-dense deuterium by scientists at the University of Gothenberg, in Sweden. A cubic centimeter of the stuff would weigh 287 lbs. (130 kg). UDD is 100,000 times more dense than water, and a million times more dense than deuterium ice, which is a common fuel in laser-ignited fusion projects. The researchers say that, if (big if) the material can be produced in large quantities, it would vastly improve the chances of starting a fusion reaction, as the atoms are much closer together. Such a D-D fusion reaction would be cleaner than one involving highly radioactive tritium. Many outlets have picked up the same press release that Science Daily printed pretty much verbatim (as is their wont); there doesn't seem to be much else about this on the Web. Here's the home page of one of the researchers. The press release gives no hint as to how the UDD was produced. Reader wisebabo asks: "I can easily imagine a material being compressed by some heavy duty diamond anvil to reach this density, the question is: what happens when you let the pressure off? Will it expand (explosively one would presume) back to its original volume?"
Woo-hoo, warp drive, here we come!
Oh, only "cold fusion here we come"? Fine, lets just solve our enrgy crisis then. *kicks rock, wishes for holodeck*
Your ad here. Ask me how!
Sounds like the university of gothenberg should just go walk nibbler.
"I can easily imagine a material being compressed by some heavy duty diamond anvil to reach this density, the question is: what happens when you let the pressure off? Will it expand (explosively one would presume) back to its original volume?"
Simple answer, known by all: Duct Tape.
RS
Shoes for Industry. Shoes for the Dead.
"Highly Radioactive Tritium" - I'm assuming they meant something concerning the very energetic neutrons produced in D-T fusion. Tritium by itself can't be considered highly radioactive by any stretch of the imagination. They put the stuff in my watch with thin glass for a shield, for Pete's sake!
Imaging putting a little bit of that in ones shoe...a great laugh!
FIRST - there is no claim for an observable amount of matter in the D(-1) state. It isn't "microscopic amounts" - for "microscopic" means "visible in a microscope". Do the math, fellow NBF visionaries: 2.3 picometers ... if it were a lattice compound ... would be about 440^3 units per cubic nanometer, or 440,000^3 (about 85E15 or 85 quadrillion atoms in a cubic micrometer box. Nothing doing. They're measuring the energy (~600eV) spectroscopically, from the FRAGMENTS of the supposed union. This is not a union-of-deuterons lasting nanoseconds, or microseconds, or milliseconds, or seconds. No, these are the fragments that lasted just long enough for the D(-1) state to hold together in a laser beam for ATTOSECONDS. (That's what those little "as" annotations are on their viewgraph).
SECOND, while it is nice to foster the conjecture that such matter IF microscopically attainable, IF stable enought to survives the time-of-flight from source to fusion reactor, IF the energy-cost-of-production is far less than the increased odds (and useful energy return) of the attendant fusion exists ... THEN it is a great and wonderful thing.
THIRD, single D(-1) pseudonucleons may well exist for nanoseconds per KURT9's thesis, but again ... nanoseconds is very much too short for deeply sub-relativistic ballistic particles to traverse a source (the laser-and-"compression" chamber) to the fusion reaction chamber. Even if they only exist as single diatomic particles, lifetimes have to be raised at least into the microseconds. For practical energy production in the reactor proper (let's say, 250 MW thermal), 4.88E20 diatomic Rydberg nucleons would have to be created (assuming 3.23MeV per fusion of D(-1) to get to 4He) ... and remembering that 4He is the least likely product produced.
FOURTH (per last part of Third), the 2D + 2D = 4He reaction is well known to be very improbable in a single step, since there are LOWER ENERGY intermediate products that bleed off the excited spin-state fusion reaction (one of the key 'first principles' of fusion physics). Per the excellent if brief article in WikiPedia,
50% ... D + D = T + p ... D + D = 3He + n
50%
Researching further, D + D = 4He occurs about one in a dozen million fusion reactions nominally.
FIFTH, summing goatse.cx guy's "facts" together and this looks like yet another fruitless (for fusion) avenues of research. There is only hope, and not a shred of evidence that the D(-1) Rydberg CAN be made in 1E20 nucleons/second quantities, no reference to the overall energy-of-formation, no evidence that the diatoms can exist for more than attoseconds, nothing but speculative wishes that such a material holds promise to D+D=4He reactions (which is just an uber-popular topic, anyway). Therefore, it gets a 3 star SnakeOil award, coupled with 2 stars for the actual science, the novelty of the discovery, and the fine department of Physics at Gothenberg for letting these two obviously talented, and quite frankly queer, researchers have their limelight.
So, in summary, I have to say: "Sorry, dude, I just don't think it'll work."
=smudge=
Is it just my observation, or is eldavojohn an idiot?
There has been a long search for metallic hydrogen, which is supposed to be (once made under high pressure) possibly both stable and superconducting at room temperature.
Given that metallic hydrogen is also supposed to be quite dense, I have to wonder if they haven't made metallic deuterium.
I don't think they could do much better than claim a major breakthrough in Hot Double-D Reactions.
If you didn't come to party don't bother knocking on my door. Prince '1999'
We're talking about density here. Besides a single atom of helium weighs more (than a single atom of D). It has two protons and two neutrons.
The sun is much hotter. Fusion is a product of temperature and density.
The world is made by those who show up for the job.
It's so dense that a single pound of it weighs over 10,000 pounds!
ASCII stupid question, get a stupid ANSI
The centre of the sun is less dense than you might think, owing to thermal and radiation pressure.
The energy from the aforementioned fusion counteracts the pressure from the outer layers pushing in. This state is one of equilibrium; reduce the rate of reaction and the core contracts, speeding fusion, increase the rate of reaction and the core expands, slowing the fusion back down again. The estimated density of the sun is much, much lower than the density would be for a non-fusing body of the same mass. If anything, this discrepancy will be more noticeable in the core, where the temperature is highest.
If no fusion reactions were occurring, which is what will happen when the fuel runs out, the core would contract until it became electron-degenerate matter, the material of a white dwarf star. With a more massive star, the contraction would continue past that point until neutron degeneracy took over (leading to a neutron star), or it passed the Swartzchild radius (leading to a black hole).
Erotic is when you use a feather. Exotic is when you use the whole chicken.
You're right -- just think of what a boon this will be to the mining and drilling industries.
Because you know, that's all it's going to be good for. It's dense enough to fall through granite and limestone like they were tissue paper. I'm getting a figure of mechanical pressure that's about twice what hardened steel can take.
Fill a soda can with this stuff and watch it shoot down into the center of the Earth, with nothing you can do to stop it. If it's any consolation, after that it will probably fuse and explode.
I, for one, welcome our new swedish doomsday weapon.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
The FA says a 10cm cube, i.e. 1000 cubic centimetres, would weigh 130 tonnes.
Metric isn't that hard.
If 10 cm * 10 cm * 10 cm = 1000 cm^3 weighs 130 000 kg, then 1 cm * 1 cm * 1 cm = 1 cm^3 weighs 130 kg.
Usage: km/h for speed (kilometers per hour); kph for very slow impulses (kilopond hours).
I'm having fun imagining him trying to lift and lightly toss 35 thousand pounds of anything.
Fine, lets just solve our enrgy crisis then. *kicks rock, wishes for holodeck*
If we really wanted to, we could solve it quite easily. There's many centuries of Uranium and Thorium to burn in fission reactors, and nuclear waste is solved technically. (Again, the problem is political.) We haven't taken more than the first step to tapping the potential of wave energy, there's a lot more wind to harness. Solar Thermal could benefit from economies of scale and improved distribution, and there's tremendous potential untapped in the world's deserts.
There's even a market for Orbital Solar Power Satellites -- namely for remote military outposts that would otherwise need to truck in fuel for generators. (An order of magnitude greater cost is acceptable in that case, but this would start the cycle of industrial innovation and reduction of costs from economies of scale, and would lead to widespread Solar Power for civilian use.)
We could stop using fossil fuels right now, from a technical standpoint. It's just that we don't want to, for a variety of economic, political, and superstitious reasons.