With metallic hydrogen, the atoms need be broken out of the metallic matrix, but that probably takes a lot less energy.
Quote from: Proponent on 11/08/2016 02:38 pmWith metallic hydrogen, the atoms need be broken out of the metallic matrix, but that probably takes a lot less energy. Once that happens, aren't the individual atoms going to want to immediately revert to the H-H configuration (covalent bond) with commensurate release of energy?
Metallic deuterium would allow self-detonating fusion devices. Friedwardt Winterberg has a design for a non-fission triggered D-T device (it's in one of his papers on viXra, since the arXiv wouldn't allow it.) He used standard chemical explosives in a rather complicated process. Such explosives pack the equivalent of ~350 s Isp. An implosion device made of solid metallic deuterium wouldn't need high explosives, since it would pack ~x10 the energy or so. And it'd be fusion fuel. Just squirt some tritium into the very centre.Alternatively wrap lithium deuteride in a metallic deuterium magnetic compression target.Also, superconducting rings of metallic hydrogen could be launched via a linear accelerator to be mass-beam pellets to push spacecraft. Ramming into a magnetic field around the vehicle at high speed would probably cause the superconductivity to quench, blasting the ring into high speed hydrogen plasma.
Quote from: qraal on 11/09/2016 10:29 amMetallic deuterium would allow self-detonating fusion devices. Friedwardt Winterberg has a design for a non-fission triggered D-T device (it's in one of his papers on viXra, since the arXiv wouldn't allow it.) He used standard chemical explosives in a rather complicated process. Such explosives pack the equivalent of ~350 s Isp. An implosion device made of solid metallic deuterium wouldn't need high explosives, since it would pack ~x10 the energy or so. And it'd be fusion fuel. Just squirt some tritium into the very centre.Alternatively wrap lithium deuteride in a metallic deuterium magnetic compression target.Also, superconducting rings of metallic hydrogen could be launched via a linear accelerator to be mass-beam pellets to push spacecraft. Ramming into a magnetic field around the vehicle at high speed would probably cause the superconductivity to quench, blasting the ring into high speed hydrogen plasma.This post is the best piece of hard Sci-Fi I've read this year.
Quote from: DMeader on 11/09/2016 04:00 pmQuote from: Proponent on 11/08/2016 02:38 pmWith metallic hydrogen, the atoms need be broken out of the metallic matrix, but that probably takes a lot less energy. Once that happens, aren't the individual atoms going to want to immediately revert to the H-H configuration (covalent bond) with commensurate release of energy?No doubt, and, rereading the article and clicking through the links, the idea seems to be to rely on that energy alone, not bothering with the oxygen.An Isp of 1700 s corresponds to an effective exhaust velocity of about 17 km/s. For getting to LEO that's actually too high, if the objective is to minimize the amount of metallic hydrogen. It might be optimal to add a cheap working fluid, ideally a monatomic one. That would have the added advantage of keeping the temperature down.
Metallic deuterium would allow self-detonating fusion devices.
Quote from: qraal on 11/09/2016 10:29 amMetallic deuterium would allow self-detonating fusion devices. not sure that that is a good thing given human inhumanity to their fellow humans in large numbers, --despite the good non destructive (non-murdilating) uses such things would have.
AbstractProducing metallic hydrogen has been a great challenge to condensed matter physics. Metallic hydrogen may be a room temperature superconductor and metastable when the pressure is released and could have an important impact on energy and rocketry. We have studied solid molecular hydrogen under pressure at low temperatures. At a pressure of 495 GPa hydrogen becomes metallic with reflectivity as high as 0.91. We fit the reflectance using a Drude free electron model to determine the plasma frequency of 32.5 ± 2.1 eV at T = 5.5 K, with a corresponding electron carrier density of 7.7 ± 1.1 × 1023 particles/cm3, consistent with theoretical estimates of the atomic density. The properties are those of an atomic metal. We have produced the Wigner-Huntington dissociative transition to atomic metallic hydrogen in the laboratory.
In 1935 a pair of physicists predicted that if the pressure of hydrogen were raised to about 25 times that of atmospheric pressure, it would turn into a solid metal. Experimentalists ever since have tried and failed to spot this transition, even after raising the pressure of hydrogen to millions of times atmospheric pressure. Now, the transition to solid metallic hydrogen may have been reached. Physicists in the United States say that by crushing a tiny amount of hydrogen between the tips of two flat-tipped diamonds at cryogenic temperatures they've raised the pressure to nearly 5 million times atmospheric pressure, causing the hydrogen to reflect light like a metal. They still don't have evidence the pressurized hydrogen is a solid. But even the claim that it is metallic is highly controversial. Other high-pressure physicists question some of the procedures used in the new study, and say they need more proof before they'll concede that the 80-year quest is over.
And because the research was published in Science, Nature tries to spoil the party: http://www.nature.com/news/physicists-doubt-bold-report-of-metallic-hydrogen-1.21379
An update including a picture of the sample they have produced.http://www.sciencealert.com/hydrogen-has-been-turned-into-a-metal-for-the-first-time-everAnd here's the paper published in Science.QuoteAbstractProducing metallic hydrogen has been a great challenge to condensed matter physics. Metallic hydrogen may be a room temperature superconductor and metastable when the pressure is released and could have an important impact on energy and rocketry. We have studied solid molecular hydrogen under pressure at low temperatures. At a pressure of 495 GPa hydrogen becomes metallic with reflectivity as high as 0.91. We fit the reflectance using a Drude free electron model to determine the plasma frequency of 32.5 ± 2.1 eV at T = 5.5 K, with a corresponding electron carrier density of 7.7 ± 1.1 × 1023 particles/cm3, consistent with theoretical estimates of the atomic density. The properties are those of an atomic metal. We have produced the Wigner-Huntington dissociative transition to atomic metallic hydrogen in the laboratory.http://science.sciencemag.org/content/early/2017/01/25/science.aal1579?More in this article.Metallic hydrogen created in diamond viseQuoteIn 1935 a pair of physicists predicted that if the pressure of hydrogen were raised to about 25 times that of atmospheric pressure, it would turn into a solid metal. Experimentalists ever since have tried and failed to spot this transition, even after raising the pressure of hydrogen to millions of times atmospheric pressure. Now, the transition to solid metallic hydrogen may have been reached. Physicists in the United States say that by crushing a tiny amount of hydrogen between the tips of two flat-tipped diamonds at cryogenic temperatures they've raised the pressure to nearly 5 million times atmospheric pressure, causing the hydrogen to reflect light like a metal. They still don't have evidence the pressurized hydrogen is a solid. But even the claim that it is metallic is highly controversial. Other high-pressure physicists question some of the procedures used in the new study, and say they need more proof before they'll concede that the 80-year quest is over.http://science.sciencemag.org/content/355/6323/332
The paper that this is all based on is available here: https://arxiv.org/abs/1610.01634
Quote from: Nilof on 01/27/2017 08:44 amThe paper that this is all based on is available here: https://arxiv.org/abs/1610.01634That is not the peer reviewed paper you can tell from the date.