Author Topic: Metallic Hydrogen is real!  (Read 37777 times)

Offline Stormbringer

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Metallic Hydrogen is real!
« on: 11/05/2016 08:21 pm »
http://www.nextbigfuture.com/2016/11/if-newly-created-metallic-hydrogen.html

http://www.nextbigfuture.com/2016/11/co-discover-of-metallic-hydrogen-wrote.html

ISP is slightly more than three times the shuttles for 1/3 the volume/mass.

Quote
Some Remarkable Properties of Metallic Hydrogen
•Recombination of hydrogen atoms releases 216 MJ/kg
•Hydrogen/Oxygen combustion in the Shuttle: 10 MJ/kg
•TNT 4.2 MJ/kg
•Theoretical Specific Impulse, Isp
•Metallic Hydrogen 1000-1700s
•Molecular hydrogen/oxygen ~460 s (space shuttle)
•Metallic density
about 12-13 [Personal Edit ( is actually) ] 15 fold of liquid molecular hydrogen [lab results of actual metallic hydrogen was 15 times denser]
•Sufficient thrust for single-stage to orbit; explore outer planets

http://www.nextbigfuture.com/2016/11/harvard-researchers-created-solid.html

they haz pictures of it : 

« Last Edit: 11/05/2016 08:32 pm by Stormbringer »
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Offline ulm_atms

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Re: Metallic Hydrogen is real!
« Reply #1 on: 11/05/2016 11:19 pm »
The real trick will be if it is metastable at normal pressures.  If that turns out true, this will be a breakthrough of huge proportions.  Like...space changing.

IF "big if" everything turned out fine, the 6K combustion temps (if you don't dilute it) would be the next issue for turning it into a rocket fuel.  Is there any material that can withstand that temp?  I can't think of any currently.

I wonder what state the combustion is in "gas or plasma" and if it is in a type of charged state.  If it's charged plasma, I would think some type of magnetic field containment could keep it from cooking the chamber (kinda like the plasma fusion experiments of millions of kelvins, etc...)

Anyways, it is cool to see that the theory for metallic hydrogen seems to be verified and is possible.  Now if we could get to that warp drive thing before I die....that would be nice.... ;D

Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #2 on: 11/05/2016 11:28 pm »
isn't it dimagnetic at cryogenic temps? wouldn't that mean it would be dimagnetic  in solid form even if it was no longer at cryogenic temps? and after it is burned isn't it a plasma?

I'm just asking. i don't know the answers except the dimagnetic at cryogenic temps part.
« Last Edit: 11/05/2016 11:29 pm by Stormbringer »
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Offline ulm_atms

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Re: Metallic Hydrogen is real!
« Reply #3 on: 11/05/2016 11:34 pm »
Me neither...that's why I asked.

You are correct at cryo temps.  But once 'ignited' and at apparently 6k degrees....I don't know.

Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #4 on: 11/05/2016 11:45 pm »
my guess is at that temp it would be a plasma. i think it would have to be. its the bit in between that worries me.
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Offline KelvinZero

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Re: Metallic Hydrogen is real!
« Reply #5 on: 11/06/2016 02:30 am »
IF "big if" everything turned out fine, the 6K combustion temps (if you don't dilute it) would be the next issue for turning it into a rocket fuel.  Is there any material that can withstand that temp?  I can't think of any currently.
Laymans guess: I bet this temperature is not such a big problem for a metastable metallic hydrogen rocket, even though it is a big problem for NTR. For NTR, the problem is safely containing your extremely hot radioactive elements and somehow transferring this temperature to your hydrogen propellent. For metallic hydrogen, the heat is generated directly in the propellant you are allowed to throw away as quickly as possible. You can have large nozzles to distribute the heat.


Offline Space Ghost 1962

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Re: Metallic Hydrogen is real!
« Reply #6 on: 11/06/2016 04:05 am »
my guess is at that temp it would be a plasma. i think it would have to be. its the bit in between that worries me.

A cross product term in the Hamiltonian due to diamagnetism would mean a non canonical solution as a plasma.

Would require applying Biot-Savart law for a solution. Interesting.

Offline allhumanbeings07

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Re: Metallic Hydrogen is real!
« Reply #7 on: 11/06/2016 11:06 am »
Looking through some of the previous attempts to produce metallic hydrogen, it seems like there was some talk that it might not even be a solid at all but some new fluid-like phase of matter. Is the mH Harvard claims to have produced a solid / solid-like? Can't find it. In one of Dr. Silvera's powerpoint presentations he makes reference both to a theorized liquid metallic and a solid metallic phase.

http://www.nasa.gov/pdf/637123main_Silvera_Presentation.pdf

^ (A few slides down)

Another thing, looking through Dr. Silvera's paper on the potential space flight applications of mH he did for NASA, he mentions that due to the extreme temperatures mH would produce on combustion it would be necessary to dilute it with a weaker combustible. He mentions both water and liquid hydrogen, and uses LH/mH mixes in his calculated paper rockets. Is there any theoretical problem though with mixing mH with another rocket fuel like RP-1 or Methane as opposed to LH? Skipping LH, if possible, might save problems with cryogenics, density or toxicity (would mH be toxic as well?) while keeping cost to a minimum.

https://dash.harvard.edu/bitstream/handle/1/9569212/Silvera_Metallic.pdf?sequence=2
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Offline eeergo

Re: Metallic Hydrogen is real!
« Reply #8 on: 11/06/2016 04:16 pm »
Looking through some of the previous attempts to produce metallic hydrogen, it seems like there was some talk that it might not even be a solid at all but some new fluid-like phase of matter. Is the mH Harvard claims to have produced a solid / solid-like? Can't find it. In one of Dr. Silvera's powerpoint presentations he makes reference both to a theorized liquid metallic and a solid metallic phase.

http://www.nasa.gov/pdf/637123main_Silvera_Presentation.pdf

The phase diagram is clearly seen in Figure 1 of the paper https://arxiv.org/pdf/1610.01634v1.pdf

There are two pathways followed, one toward fluid (liquid) mH and another for solid, which is the one reported in this paper. The isobaric process at ~150Gpa with increasing temperature is the one leading to LmH.

The paper is called "Observation of the Wigner-Huntington Transition to Solid Metallic Hydrogen", should be quite clear what their claim is ;)
« Last Edit: 11/06/2016 04:16 pm by eeergo »
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Offline allhumanbeings07

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Re: Metallic Hydrogen is real!
« Reply #9 on: 11/06/2016 05:01 pm »
Cheers, yeah I saw the phase diagram and was looking at it... only it's been a long time since 10th grade chem. It seemed that should be a lot less difficult to produce than solid, so if we were hearing about producing metallic hydrogen it'd've been the easier one first.

But after looking through the paper again and seeing those few references to lmH, it seems it's already been synthesized? Is it just an experimental curiosity then without applications?
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Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #10 on: 11/06/2016 05:18 pm »
that remains to be seen. my understanding of the recent articles cited is that they are following on with experiments to see if it remains a solid as they lower the pressure, as they raise the temperature or do both at the same time. they do not know yet if it will remain a solid.

also its not as simple as solid, liquid and condensed gas... the articles seem to say that the solid form has at least three probably different organizational forms.
« Last Edit: 11/06/2016 05:19 pm by Stormbringer »
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Offline Star One

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Metallic Hydrogen is real!
« Reply #11 on: 11/06/2016 06:12 pm »
From what the articles are saying it is supposedly metastable in normal conditions. After all diamonds are metastable so there's nothing to say it shouldn't be.

There was another article on there talking about making lightweight floating cities out of it. Not sure how you could do that as with the energy stored in it wouldn't that be like living in a city made out of TNT.

By the way why is it appearing on a site like this first rather than a more mainstream science site?
« Last Edit: 11/06/2016 06:15 pm by Star One »

Offline eeergo

Re: Metallic Hydrogen is real!
« Reply #12 on: 11/06/2016 06:13 pm »
Cheers, yeah I saw the phase diagram and was looking at it... only it's been a long time since 10th grade chem. It seemed that should be a lot less difficult to produce than solid, so if we were hearing about producing metallic hydrogen it'd've been the easier one first.

But after looking through the paper again and seeing those few references to lmH, it seems it's already been synthesized? Is it just an experimental curiosity then without applications?

The "new fluid state" you were mentioning in the previous post might be related to this: http://www.nature.com/nature/journal/v431/n7009/abs/nature02910.html and https://www.ncbi.nlm.nih.gov/pubmed/16196937. In particular: "[...] liquid metallic hydrogen, finding that it may represent a new type of ordered quantum fluid." ==> LmH would be driven from a superconducting to a superfluid state by applied magnetic fields.

It should be noted SmH was already claimed to have been observed in 2012 http://www.nature.com/news/metallic-hydrogen-hard-pressed-1.10817 with similar evidence, although they were lacking in IR measurements that would have provided more conclusive proof.
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Offline Elmar Moelzer

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Re: Metallic Hydrogen is real!
« Reply #13 on: 11/06/2016 06:39 pm »
My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #14 on: 11/06/2016 06:45 pm »
Maybe the first use could be on a 2nd stage. That would not enable a SSTO but could reduce rocket size considerably by increasing payload mass ratio.
Or, in the case of a future rocket similar to F9R, could enable S2 reuse.
« Last Edit: 11/06/2016 06:46 pm by IRobot »

Offline WBailey

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Re: Metallic Hydrogen is real!
« Reply #15 on: 11/06/2016 06:55 pm »
What about military applications? Solid hydrogen solid propellant? Miniature ICBMs?

Offline allhumanbeings07

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Re: Metallic Hydrogen is real!
« Reply #16 on: 11/06/2016 06:59 pm »
My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

 :)

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?
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Offline WBailey

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Re: Metallic Hydrogen is real!
« Reply #17 on: 11/06/2016 07:03 pm »
Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?

There are the free radical propellants, though you could say they have been synthesized. They just don't like to stay synthesized.

Offline savuporo

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Re: Metallic Hydrogen is real!
« Reply #18 on: 11/06/2016 07:45 pm »
By the way why is it appearing on a site like this first rather than a more mainstream science site?

It kind of was here back in August: https://www.sciencenews.org/article/pressure-make-metallic-hydrogen
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Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #19 on: 11/06/2016 07:58 pm »
My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

 :)

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?
yeah. go to project rho and look at their engine table. several of the fuels listed there are pretty much what you are asking about. E.G; metastable helium.

http://www.projectrho.com/public_html/rocket/enginelist.php#metaheliumhestar

if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds. so if you could find either monopoles or some other suitable nucleon and electron substitute you could vastly out-perform even antimatter engines.

we don't have monopoles but we have created synthetic atoms out of stuff that doesn't normally form atoms such as kaons and muons. they are very unstable and last a tiny amount of time before breaking up. but there is reason to hope that some combination or some amount of a material like this may be more persistent.

Neutrons die in 11 or so minutes when alone but are stable possibly forever in an atomic nucleus. Likewise kaonium (or was it muonium?) lasts longer than individual particles of their species.

« Last Edit: 11/06/2016 08:16 pm by Stormbringer »
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Offline KelvinZero

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Re: Metallic Hydrogen is real!
« Reply #20 on: 11/06/2016 08:47 pm »
How much of a case has been made that metallic hydrogen will be metastable and up to what pressure? I couldn't find any information on that but thought I had gathered from somewhere that metastability does not imply anything like ambient pressure or that it can be used to build structures, as I saw thrown around in a few article headings.

What is claimed here is just that we have created some metallic hydrogen, right? What sort of confidence is there in it's properties?

Offline hkultala

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Re: Metallic Hydrogen is real!
« Reply #21 on: 11/06/2016 08:51 pm »
What is the reason for the high isp of metallic hydrogen?

Offline Sam Ho

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Re: Metallic Hydrogen is real!
« Reply #22 on: 11/06/2016 09:30 pm »
By the way why is it appearing on a site like this first rather than a more mainstream science site?
It kind of was here back in August: https://www.sciencenews.org/article/pressure-make-metallic-hydrogen
The rocketry application was published in a 2009 conference paper, so it isn't all that new, but back then there were no samples of metallic hydrogen.

Silvera, Isaac F. and John W. Cole. 2010. Metallic hydrogen: The most powerful rocket fuel yet to exist. In International Conference on High Pressure Science and Technology, Joint AIRAPT-22 & HPCJ-50 : [proceedings] : 26-31 July 2009, Tokyo, Japan. Journal of Physics Conference Series 215(1): 012194.

http://nrs.harvard.edu/urn-3:HUL.InstRepos:9569212

What is the reason for the high isp of metallic hydrogen?

The quoted Isp of 1700s from the above conference paper is based on assuming that metastable metallic hydrogen exists at relatively low pressure, and using it as a monopropellant, from the heat of recombination to molecular hydrogen.

Offline allhumanbeings07

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Re: Metallic Hydrogen is real!
« Reply #23 on: 11/06/2016 10:07 pm »
How much of a case has been made that metallic hydrogen will be metastable and up to what pressure? I couldn't find any information on that but thought I had gathered from somewhere that metastability does not imply anything like ambient pressure or that it can be used to build structures, as I saw thrown around in a few article headings.

What is claimed here is just that we have created some metallic hydrogen, right? What sort of confidence is there in it's properties?

Seems that since synthesizing last month the folks at Harvard have been keeping the sample in liquid nitrogen so far. After poking it some more, Dr. Silvera has said that there looking at several potential methods of gradually heating it up. Since they're actively keeping it cold right now, I figure we'll have to know if it's metastable at normal temps within a relatively short period of time.
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Offline savuporo

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Re: Metallic Hydrogen is real!
« Reply #24 on: 11/06/2016 10:57 pm »
Metallic hydrogen: The most powerful rocket fuel yet to exist.
Bit of a hyperbole there, no ? Project Orion ? Also, NERVA certainly existed and could probably exceed this purely theoretical ISP of a purely theoretically metastable material.
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Offline allhumanbeings07

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Re: Metallic Hydrogen is real!
« Reply #25 on: 11/06/2016 11:04 pm »
Metallic hydrogen: The most powerful rocket fuel yet to exist.
Bit of a hyperbole there, no ? Project Orion ? Also, NERVA certainly existed and could probably exceed this purely theoretical ISP of a purely theoretically metastable material.

Well, it doesn't seem that the material itself is theoretical any longer, and given Dr. Silvera's stated intentions its metastability (or lack thereof) should be proven fact soon...
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Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #26 on: 11/07/2016 03:00 am »
also its not as simple as solid, liquid and condensed gas... the articles seem to say that the solid form has at least three probably different organizational forms.

That's the most critical part for consideration of a solid plasma.

In Frank Chen's unpublished continuation to his Plasma Physics book, (which I have a draft copy of), he discusses theoretical solid plasmas - the organization of the "material" will matter.

(Around this time had a discussion/notes of a fusion "combustion chamber" based on a solid plasma, however was told that no one would ever build a large enough vehicle for its use, since the Saturn V was considered "uneconomic" due to size. ;) )
yeah. uneconomic. as in the govt didn't want to pay for it once we won the space race. but there is lots of neat stuff coming up that i, as a laymen type science dilitante, barely understand. like the nucleus of heavy atoms can assume a hollow form. I read that just recently. all the protons and neutrons form a structure something like a blastula. which is really weird.
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Offline john smith 19

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Re: Metallic Hydrogen is real!
« Reply #27 on: 11/07/2016 03:57 am »
The rocketry application was published in a 2009 conference paper, so it isn't all that new, but back then there were no samples of metallic hydrogen.

Silvera, Isaac F. and John W. Cole. 2010. Metallic hydrogen: The most powerful rocket fuel yet to exist. In International Conference on High Pressure Science and Technology, Joint AIRAPT-22 & HPCJ-50 : [proceedings] : 26-31 July 2009, Tokyo, Japan. Journal of Physics Conference Series 215(1): 012194.

http://nrs.harvard.edu/urn-3:HUL.InstRepos:9569212
The idea has been been around since at least 1970 when RL Forward of Hughes labs did a project for IIRC the USAF on (IIRC) "Energetic materials" along with things like antimatter and N8 (yes that's a ring of 8 Nitrogen atoms). However I think they were still expecting metallic H2 to show up around the 25GPa, rather than the  actual level 18x higher.

Various groups seem to be getting close to making N8 but these groups specialize in making and handling stuff like this. I saw a chemistry blog it was mentioned on. The thing they'd made violently decomposed when exposed to the IR beam in a spectrometer  :o

This suggest they will be lowering the pressure on this sample very carefully.
Bit of a hyperbole there, no ? Project Orion ?
Strictly it's not. Orion (and the fission fragment rocket) are both systems with high (relative to chemical) fuels. NERVA was targeting 900-950secs at most and if liquid metallic hydrogen can be made to exist at reasonable pressures (IE 2-3 atm) then it's T/W will also be 10-20x better than NERVA as well.
Quote
Also, NERVA certainly existed and could probably exceed this purely theoretical ISP of a purely theoretically metastable material.
No. The Isp for a NTR is set by the molecular weight of the fuel, the temperature and pressure you raise it to and the size of the nozzle you expand the flow through.

A big nozzle can put a 10s of secs on an Isp, not 800secs.
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Offline ppnl

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Re: Metallic Hydrogen is real!
« Reply #28 on: 11/07/2016 05:20 am »
My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

 :)

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?
yeah. go to project rho and look at their engine table. several of the fuels listed there are pretty much what you are asking about. E.G; metastable helium.

http://www.projectrho.com/public_html/rocket/enginelist.php#metaheliumhestar

if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds. so if you could find either monopoles or some other suitable nucleon and electron substitute you could vastly out-perform even antimatter engines.

we don't have monopoles but we have created synthetic atoms out of stuff that doesn't normally form atoms such as kaons and muons. they are very unstable and last a tiny amount of time before breaking up. but there is reason to hope that some combination or some amount of a material like this may be more persistent.

Neutrons die in 11 or so minutes when alone but are stable possibly forever in an atomic nucleus. Likewise kaonium (or was it muonium?) lasts longer than individual particles of their species.

No, you cannot exceed e=mc^2. Any energy that you store in "chemical bonds" will simply show up as extra mass of the fuel. The energy per unit mass cannot surpass matter/antimatter.


Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #29 on: 11/07/2016 07:06 am »
I didn't say you could. E=MC^2 is germane though. only-- in the case of massive monopoles packed into a lot less space than say the nucleons involved in antimatter annihilation reactions there is a heck of a lot more M and consequently a heck of a lot more E. Also the nuclear and electronic bonding energy scales inversely with the bonding length and the bonding length of an atom made of monopoles would be orders of magnitude shorter and thus more energetic.

Now assuming we can't haz monopoles but can find something on the scale of axions or even up to a similar mass to  kaons or muons the energy available for other synthetic atoms might be a lot less because the scaling would be different and probably larger than hypothetical monopoles but still probably less than ordinary matter atoms. thus even if you are constrained by E=MC^2 all the terms except C in that equation are variables.

depending on the type of monopole posited atoms made with them could be as small as:

{Taken from a hard fiction and hard fiction based game site. But large parts of the science they use in their project are based on peer reviewed science papers. this physics stuff on their site used to be footnoted with links to first sources, cites and references but that is no longer the case since they reorganized the site.}

Quote
The smallest magatoms have diameters of 3E-19 m, 300 million times smaller than an atom of conventional matter. As a typical magatom is 10,000 times heavier than a typical conventional atom, magmatter�s typical density is 1E33 kg/m3. Since force is energy per unit distance, the force needed to break a magchemical bond is larger than that needed to break an electronic chemical bond by a factor of the energy scaling (300 GeV / 13.7 eV) divided by the length scaling, or 7 million trillion (7E18). The strength of a material is usually defined as the force per unit area required to make the material fail. Since each magchemical bond can withstand 7E18 times greater force, and there are (300 million)2 times more bonds per unit area, the strength of magmatter is about 8E35 times greater than that of its normal matter equivalent.

And that would be the energy in a monopole atom's chemical bond;  not a monopole atom's nuclear bond. Of course monopoles may not exist or may not be accessible even if they do exist, but the same principle would apply to other synthetic atoms made of particles other than protons and neutrons and electrons or their antimatter equivalents.

Synthetic atoms of Kaons, Muons and hybrids of AM and matter particles have been made by researchers. Muonium (?) has a half life longer than naked muons though they only persist longer by a tiny bit. Neutrons have a half life of 11 minutes naked or for all intents and purposes forever in a stable atom except in radioactive nuclei. It is therefore not unreasonable to consider it possible for some synthetic atomic arrangement to be permanently stable as well.

We are still discovering fundamental facts about particle physics, nuclear chemistry and condensed matter physics. Last week i read that sometimes the nucleons in the nucleus of heavy atoms assumes a hollow spherical configuration despite what is known in the state of the art about nucleonic shells and the structure of an atom.

EDIT:  The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.
« Last Edit: 11/07/2016 07:21 am by Stormbringer »
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Offline Spaniard

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Re: Metallic Hydrogen is real!
« Reply #30 on: 11/07/2016 07:50 am »
EDIT:  The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.
And, what's the point in a spaceship about it's size?
It has no effect on ISP.

I think that the only problem it solves is the unstable form of antimatter. Antimatter seems to unstable to allow 1 matter atom x 1 antimatter atom ratio in safety conditions in the same spaceship.
Other forms of matter could be more stable and have better practical ratios allowing very near ISP to a theorical perfect antimatter spacechip.
ISP levels enough powerfull to allow interstellar travel viable. "Slow" (from human perspective) but practical for near stars.

Offline john smith 19

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Re: Metallic Hydrogen is real!
« Reply #31 on: 11/07/2016 11:09 am »
No, you cannot exceed e=mc^2. Any energy that you store in "chemical bonds" will simply show up as extra mass of the fuel. The energy per unit mass cannot surpass matter/antimatter.
And they are not actually suggesting you can.  they are suggesting that by making atoms which are smaller (because they are made of unconventional particles to begin with) they would have stronger, shorter bonds. This creates (theoretically) matter with "impossible" densities.

Of course you're now making fuel atom by atom, which is likely to be pretty slow.   :(
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Offline as58

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Re: Metallic Hydrogen is real!
« Reply #32 on: 11/07/2016 11:24 am »
Speculating about the metastability of metallic hydrogen can maybe be called discussion about Advanced Concepts, but magnetic monopoles, (meta)stable kaonium etc. takes this IMO to New Physics with the rest of the 'out there' stuff.

Offline ppnl

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Re: Metallic Hydrogen is real!
« Reply #33 on: 11/07/2016 07:08 pm »


EDIT:  The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.

I don't think space taken by fuel is an important limit when dealing with things like antimatter.

If monopoles exist a better use for them may be to catalyze the decay of protons. You get matter energy conversion without the expensive and dangerous antimatter.

But this is getting off the subject of metalic hydrogen.

Offline RobLynn

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Re: Metallic Hydrogen is real!
« Reply #34 on: 11/08/2016 09:17 am »
It could substantially improve the Isp of an Orion pulsed nuclear rocket - if used as the implosive driver of fission bombs, and perhaps also adding a metastable pit of Deuterium or Tritium metal (with 30 or 45x liquid protium density) to the core of a fission bomb could greatly enhance their yields.
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Offline Proponent

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Re: Metallic Hydrogen is real!
« Reply #35 on: 11/08/2016 02:38 pm »
What is the reason for the high isp of metallic hydrogen?

I think a big part of what's going on with metallic hydrogen is that the hydrogen is essentially in atomic rather than molecular form.  To burn a mole of molecular hydrogen, first you need to break a mole's worth of H-H bonds: that takes 436 kJ.  With metallic hydrogen, the atoms need be broken out of the metallic matrix, but that probably takes a lot less energy.  So, the heat released by burning metallic hydrogen is probably something like the heat of combustion of molecular hydrogen, 286 kJ/mol, plus 436 kJ/mol = 722 kJ/mol.

Now, could we get some metallic oxygen, too?  Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol.  Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

Offline RotoSequence

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Re: Metallic Hydrogen is real!
« Reply #36 on: 11/08/2016 03:09 pm »
Now, could we get some metallic oxygen, too?  Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol.  Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not ;). Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.
« Last Edit: 11/08/2016 03:11 pm by RotoSequence »

Offline gargoyle99

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Re: Metallic Hydrogen is real!
« Reply #37 on: 11/08/2016 03:59 pm »
Now, could we get some metallic oxygen, too?  Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol.  Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not ;). Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.

Oxygen will convert to a metallic allotrope at about 132 GPa. Many non-metal atoms have a metallic allotrope at sufficient pressures.

https://en.wikipedia.org/wiki/Solid_oxygen#Metallic_oxygen

https://en.wikipedia.org/wiki/Nonmetal#Allotropes

It just means that when pressures are sufficient to pack the atoms so tightly together that the valence electrons begin to migrate freely through the substance then it will demonstrate metallic properties.

As far as I know, most of these metallic allotropes are not meta-stable and probably not all that useful for spaceflight unless you have a way to sustain those pressures without using massive containing structures.

Offline qraal

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Re: Metallic Hydrogen is real!
« Reply #38 on: 11/09/2016 10:29 am »
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.

Offline RotoSequence

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Re: Metallic Hydrogen is real!
« Reply #39 on: 11/09/2016 03:40 pm »
Now, could we get some metallic oxygen, too?  Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol.  Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not ;). Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.

Oxygen will convert to a metallic allotrope at about 132 GPa. Many non-metal atoms have a metallic allotrope at sufficient pressures.

https://en.wikipedia.org/wiki/Solid_oxygen#Metallic_oxygen

https://en.wikipedia.org/wiki/Nonmetal#Allotropes

It just means that when pressures are sufficient to pack the atoms so tightly together that the valence electrons begin to migrate freely through the substance then it will demonstrate metallic properties.

As far as I know, most of these metallic allotropes are not meta-stable and probably not all that useful for spaceflight unless you have a way to sustain those pressures without using massive containing structures.

I stand corrected! That's very interesting information.  :)

Offline DMeader

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Re: Metallic Hydrogen is real!
« Reply #40 on: 11/09/2016 04:00 pm »
With 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?

Offline Proponent

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Re: Metallic Hydrogen is real!
« Reply #41 on: 11/09/2016 05:23 pm »
With 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.
« Last Edit: 11/09/2016 06:32 pm by Proponent »

Offline IainMcClatchie

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Re: Metallic Hydrogen is real!
« Reply #42 on: 11/09/2016 05:59 pm »
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.

This post is the best piece of hard Sci-Fi I've read this year.

Offline qraal

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Re: Metallic Hydrogen is real!
« Reply #43 on: 11/09/2016 07:54 pm »
Thank you.

Hard SF wise, the chief take-away line is that metallic hydrogen is achieved. Everything else is just engineering.

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.

This post is the best piece of hard Sci-Fi I've read this year.

Offline Sam Ho

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Re: Metallic Hydrogen is real!
« Reply #44 on: 11/09/2016 08:40 pm »
With 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.
The paper said that a monopropellant would have an Isp of 1700s and a temperature of around 7000K.  Hydrogen diluent to take the temperature down to 3500K-3800K would result in an Isp of 1030-1120s, and water diluent would have an Isp of 460-540s.

http://nrs.harvard.edu/urn-3:HUL.InstRepos:9569212

Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #45 on: 11/10/2016 01:37 am »
Metallic 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.
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Offline qraal

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Re: Metallic Hydrogen is real!
« Reply #46 on: 11/11/2016 11:47 am »
Nuclear weapons generally make co-belligerents nervous. Conventional weapons less so.

Metallic 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.

Offline Star One

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Metallic Hydrogen is real!
« Reply #47 on: 01/26/2017 10:06 pm »
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-ever

And here's the paper published in Science.

Quote
Abstract

Producing 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 vise

Quote
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.

http://science.sciencemag.org/content/355/6323/332
« Last Edit: 01/26/2017 10:14 pm by Star One »

Offline as58

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Re: Metallic Hydrogen is real!
« Reply #48 on: 01/26/2017 10:54 pm »
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

Offline Star One

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Re: Metallic Hydrogen is real!
« Reply #49 on: 01/27/2017 06:21 am »
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

Well to be fair the Science in-depth article even in the abstract from it mentions doubts.

Offline john smith 19

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Re: Metallic Hydrogen is real!
« Reply #50 on: 01/27/2017 06:49 am »
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-ever

And here's the paper published in Science.

Quote
Abstract
Producing 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 vise

Quote
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.

http://science.sciencemag.org/content/355/6323/332

This is astonishing. If it is found to be metastable and can be made in large enough quantities it can change a number of things. Room temperature superconductor. VTOL SSTO etc.

To put 1700secs in perspective the target for NERVA NTR was 825secs with a T/W ratio of 5.35:1.
combining this with Argon (cheapest noble gas) would knock the Isp down a bit, reduce the amount of MH needed and still leave a substantial Isp to give a vehicle with a reasonable PMF.

But in terms of applications everything hinges on it remaining like that for a significant time after the pressure is removed.
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Star One

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Metallic Hydrogen is real!
« Reply #51 on: 01/27/2017 06:54 am »
It was also hardly easy to manufacture considering the amount of preparation they had to make with the synthetic diamond vice alone. That pressure is ridiculous as well and how much energy did that use to create. Going to be as much about how you manufacture it as to if it's metastable.
« Last Edit: 01/27/2017 06:56 am by Star One »

Offline Welsh Dragon

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Re: Metallic Hydrogen is real!
« Reply #52 on: 01/27/2017 07:32 am »
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
Don't be childish. Extraordinary claims require extraordinary evidence. If other scientists don't try to pick your research apart, it's not interesting. This is how science works. It's not "spoiling the party".

Offline Nilof

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Re: Metallic Hydrogen is real!
« Reply #53 on: 01/27/2017 08:44 am »
The paper that this is all based on is available here: https://arxiv.org/abs/1610.01634
For a variable Isp spacecraft running at constant power and constant acceleration, the mass ratio is linear in delta-v.   Δv = ve0(MR-1). Or equivalently: Δv = vef PMF. Also, this is energy-optimal for a fixed delta-v and mass ratio.

Offline Star One

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Metallic Hydrogen is real!
« Reply #54 on: 01/27/2017 12:38 pm »
The paper that this is all based on is available here: https://arxiv.org/abs/1610.01634

That is not the peer reviewed paper you can tell from the date.
« Last Edit: 01/27/2017 12:38 pm by Star One »

Offline Nilof

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Re: Metallic Hydrogen is real!
« Reply #55 on: 01/27/2017 06:04 pm »
The paper that this is all based on is available here: https://arxiv.org/abs/1610.01634

That is not the peer reviewed paper you can tell from the date.

It is however the preprint for the same paper. Preprints pop up on the arxiv a few months before the journal article and are typically used to claim priority for the discovery. The article that ends up in the journal will usually have the same content with some minor change in editing, and mainly serves the purpose of giving the author legitimacy/career points. Specificially it's there so that researchers that haven't followed the field closely can gauge the author.

I've been through that process myself in my own publications. In the most active fields, other researchers in the same field pretty much only read the arxiv preprints because they'll be several months behind everyone else if they wait for the journal version, which will often also be behind an annoying paywall that makes citation trails harder to follow.

The published article can be found here, but as expected it is behind a paywall: http://science.sciencemag.org/content/early/2017/01/25/science.aal1579.full
« Last Edit: 01/27/2017 06:15 pm by Nilof »
For a variable Isp spacecraft running at constant power and constant acceleration, the mass ratio is linear in delta-v.   Δv = ve0(MR-1). Or equivalently: Δv = vef PMF. Also, this is energy-optimal for a fixed delta-v and mass ratio.

Offline Welsh Dragon

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Re: Metallic Hydrogen is real!
« Reply #56 on: 01/28/2017 07:09 am »
Note that while I'm sure that's true in physics, it varies by field. It's certainly not true in my field of biology. But I agree, that preprint is the next best thing if you don't have access to the actual paper.

Offline Star One

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Re: Metallic Hydrogen is real!
« Reply #57 on: 01/28/2017 08:00 am »
It's shame so many Scientific papers end up behind paywalls and expensive journals.

Offline Welsh Dragon

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Re: Metallic Hydrogen is real!
« Reply #58 on: 01/28/2017 08:10 am »
Oh don't even get me started on that! The publishing model is so broken. Never mind the fact that I have to pay thousands of pounds to have my research published open access (as is correctly required by most funding bodies now). It won't last, something's got to give. But this is very off topic here now, I do apologise. Rant over!

Offline as58

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Re: Metallic Hydrogen is real!
« Reply #59 on: 01/28/2017 08:13 am »
There are some curious patterns about how arxiv usage varies by field. Close to 100% of new astronomy/astrophysics papers are on arxiv, but for some reason it's not widely used by planetary scientists (though it seems to be improving). In physics, mathematics, and computer science some subfields are also close to 100%, while in others it's less common. It seems to me that people in more applied subfields are less likely to put their papers on arxiv.

I read very few new articles in journals because in my field almost everything goes to arxiv, usually months before publication. The exceptions are the biggest news that have embargoes and get announced in press conferences

Offline Welsh Dragon

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Re: Metallic Hydrogen is real!
« Reply #60 on: 01/28/2017 08:33 am »
Yeah it is very different. To contrast, generally the only way I read any papers before publication in journals is if I'm an author on them. This is in neuroscience.
« Last Edit: 01/28/2017 08:33 am by Welsh Dragon »

Offline Star One

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Re: Metallic Hydrogen is real!
« Reply #61 on: 01/28/2017 08:40 am »
To make up for pushing the topic off thread, what are people's thoughts on if this is likely to be metastable, does the theory strongly suggest it should or is it more uncertain?

Offline Hobbes-22

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Re: Metallic Hydrogen is real!
« Reply #62 on: 01/28/2017 09:11 am »
It was also hardly easy to manufacture considering the amount of preparation they had to make with the synthetic diamond vice alone. That pressure is ridiculous as well and how much energy did that use to create. Going to be as much about how you manufacture it as to if it's metastable.

IiRC they used a hand crank to compress the sample. The high pressure comes from concentrating a moderate force into a very small area.

Offline Katana

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Re: Metallic Hydrogen is real!
« Reply #63 on: 01/30/2017 04:05 pm »
With 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.
The paper said that a monopropellant would have an Isp of 1700s and a temperature of around 7000K.  Hydrogen diluent to take the temperature down to 3500K-3800K would result in an Isp of 1030-1120s, and water diluent would have an Isp of 460-540s.

http://nrs.harvard.edu/urn-3:HUL.InstRepos:9569212

For diluted performance, compounds contain metastable polymers of Nitrogen instead of Hydrogen may work too.

Salts of N5+ stable to 50~60 degc and salts of cyclo N5- stable to 110~120degc.
https://en.m.wikipedia.org/wiki/Pentazenium
http://science.sciencemag.org/content/355/6323/374
The latter is reported on Science the same month of metal hydrogen.

Though these maybe still not stable enough for practical propellants, but less scifi.

Derivatives of tetrazole CH2N4 or azdide N3- are already suitable / used to improve propellant performance.

Offline allhumanbeings07

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Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #66 on: 02/23/2017 09:48 pm »
well it *was* real :)

Maybe.
« Last Edit: 02/23/2017 09:53 pm by Stormbringer »
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Offline KelvinZero

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Re: Metallic Hydrogen is real!
« Reply #67 on: 02/24/2017 08:23 am »
...and it's gone

http://www.independent.co.uk/news/science/metallic-hydrogen-disappears-technology-revolutions-superconductor-faster-computers-super-efficient-a7593481.html
Glad I looked at the article. I had assumed it said disproved. The sample itself was lost.

Still could be real. It just has to be replicated, and (I guess this is redundant) repeatedly :-)

I hope it doesn't go the way of cold fusion with one guy just never giving it up and no one else ever able to find anything worthwhile. (that isn't a rigorously researched summary of cold fusion status, just my rough impression)

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #68 on: 02/24/2017 09:54 am »
This is good news, now they are forced to reproduce it earlier than expected.

Offline aquanaut99

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Re: Metallic Hydrogen is real!
« Reply #69 on: 02/24/2017 10:33 am »
This is good news, now they are forced to reproduce it earlier than expected.

On the other hand, the fact that it immediately disappeared after the failure of the diamond, and the fact that the diamond was destroyed so completely, and in a fashion that had never been seen before (indicating massive force) makes me suspect that metallic hydrogen (assuming that sample really was metallic hydrogen) is probably not metastable. Which would mean no new wonder rocket fuel (or super-explosive, or superconductor or all the other fantastic stuff some people were already expecting...). Which is kind of a bummer...
« Last Edit: 02/24/2017 10:34 am by aquanaut99 »

Offline Star One

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Re: Metallic Hydrogen is real!
« Reply #70 on: 02/24/2017 12:15 pm »
This is good news, now they are forced to reproduce it earlier than expected.

On the other hand, the fact that it immediately disappeared after the failure of the diamond, and the fact that the diamond was destroyed so completely, and in a fashion that had never been seen before (indicating massive force) makes me suspect that metallic hydrogen (assuming that sample really was metallic hydrogen) is probably not metastable. Which would mean no new wonder rocket fuel (or super-explosive, or superconductor or all the other fantastic stuff some people were already expecting...). Which is kind of a bummer...

As the article I linked to points out this is an assumption that cannot be made at this time.

Offline aquanaut99

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Re: Metallic Hydrogen is real!
« Reply #71 on: 02/24/2017 12:59 pm »
As the article I linked to points out this is an assumption that cannot be made at this time.

Everything I have heard (and note that I am absolutely no expert in this field) is that current experience in high-pressure physics argues against metallic hydrogen being metastable. In other words, it would be a huge surprise if it did turn out to be metastable (again, assuming it was actually created in the first place).

Apparently, the hype about metastable metallic hydrogen is based on a single theoretical paper from the early 1970s that was never experimentally proven.

I'm not saying that it's impossible that metallic hydrogen is metastable, just that it appears highly unlikely. And that therefore the hype that some articles have generated about the discovery is totally premature. Yes, it is possible (tho far from proven) that metallic hydrogen may have been created in a laboratory. Yes, that is a huge achievement in and of itself, mainly because it is something we've been trying to do for 80 years. But if it isn't metastable, then metallic hydrogen will only ever exist on this planet in minute quantities in a high-pressure lab. It will be interesting for researchers, but have no practical application whatsoever, and will never revolutionize spaceflight or give us room-temperature superconductors.

In fact, the actions of the researchers themselves indicate that they doubt that metallic hydrogen is metastable. Why else did they keep the sample in the high-pressure, ultra-cool state? After all, metastability being the key question, why wasn't the first experiment: take away the pressure and see what happens next?
« Last Edit: 02/24/2017 01:11 pm by aquanaut99 »

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #72 on: 02/24/2017 01:14 pm »
This is good news, now they are forced to reproduce it earlier than expected.

On the other hand, the fact that it immediately disappeared after the failure of the diamond, and the fact that the diamond was destroyed so completely, and in a fashion that had never been seen before (indicating massive force) makes me suspect that metallic hydrogen (assuming that sample really was metallic hydrogen) is probably not metastable.
It could jus be among the debris... repeating the experiement over and over is the best way to proceed. If you can repeat it easily, you can do tests on the properties but also on the metastability.

Offline Welsh Dragon

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Re: Metallic Hydrogen is real!
« Reply #73 on: 02/24/2017 02:05 pm »
Am I reading this right? They only did this once? What the hell were they doing announcing it if they've only done it once? What happened to reproducibility?

Offline RonM

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Re: Metallic Hydrogen is real!
« Reply #74 on: 02/24/2017 08:07 pm »
Am I reading this right? They only did this once? What the hell were they doing announcing it if they've only done it once? What happened to reproducibility?

People have been trying to create metallic hydrogen for decades. Like other groups before them, they announced ASAP to get the credit if it really worked. Reproducibility comes later. Personally, I agree with you, but it's a struggle to get grant money, so there's some showboating going on in research land.

Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #75 on: 02/25/2017 07:29 am »
well according to the article they were already prepping to redo the experiment using the same protocols and similar equipment. For instance I think they state they already have another set of diamonds for their anvil...
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Offline ppnl

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Re: Metallic Hydrogen is real!
« Reply #76 on: 02/25/2017 08:27 am »
Even if the stuff is real and metastable it is mostly only of theoretical value. It would probably cost billions to produce a gram of the stuff. Rocket fuel? Not likely.

Offline kch

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Re: Metallic Hydrogen is real!
« Reply #77 on: 02/25/2017 08:42 am »
Even if the stuff is real and metastable it is mostly only of theoretical value. It would probably cost billions to produce a gram of the stuff. Rocket fuel? Not likely.

Might make a good (expensive) firecracker, though.  ;)

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #78 on: 02/25/2017 10:58 am »
Even if the stuff is real and metastable it is mostly only of theoretical value. It would probably cost billions to produce a gram of the stuff. Rocket fuel? Not likely.
You are confusing it with anti matter. I seriously doubt that it would cost billions to produce a gram. More likely thousands per gram and on an industrial scale maybe a few dollars per gram. Still maybe too expensive for rocket fuel.

Offline ppnl

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Re: Metallic Hydrogen is real!
« Reply #79 on: 02/27/2017 06:46 am »


No, I think antimatter would cost orders of magnitude more.

The sample was a micron thick and less than the width of a human hair wide. How many specially polished and prepared diamonds will you need to use to produce a gram? How many of those diamonds are going to explode under the pressure?

And even if you produced a gram of the stuff how would you combine it into a larger object? It's unlikely you could melt a metastable substance without destroying it. And how ductile is it likely to be? Maybe less so than the diamonds you destroyed making it?

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #80 on: 02/27/2017 09:33 am »
You don't need to combine it into a larger object, actually for it to be used as a fuel, you need to keep it to very tiny pellets.

And why do you assume that diamonds will explode every time?

Offline R7

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Re: Metallic Hydrogen is real!
« Reply #81 on: 02/27/2017 11:16 am »
How many specially polished and prepared diamonds will you need to use to produce a gram?

Good question, and depends on how fast you need that gram. I estimated the broken sample weight at about 80 picograms, assuming 0.7g/cm3 density for the metallic hydrogen.

IF the process could be as simple as 1. place droplet of LH2 at the anvil, 2. compress and 3. remove a spec of metallic hydrogen then it still remains that you need either very fast process rate or vast array of said anvils, most likely both, to produce at any meaningful rate.

Anyone know what's the 'efficiency' of the compressing ie. what's the ratio of energy content of produced metallic hydrogen vs energy required to produce it. Is there some exact known upper physical limit?
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Offline R7

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Re: Metallic Hydrogen is real!
« Reply #82 on: 02/27/2017 11:25 am »
You don't need to combine it into a larger object, actually for it to be used as a fuel, you need to keep it to very tiny pellets.

I agree. Nanoparticles suspended in liquid, maybe LH2.

I don't know the exact physics of the energy release here but gut feeling says it resembles a detonation, except at 'nuclear' speed. Therefore hard to see any hope of large solid pieces of metallic hydrogen acting like solid motor grain or anything in that fashion. Resident physicists, please confirm or correct.
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Offline Proponent

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Re: Metallic Hydrogen is real!
« Reply #83 on: 02/27/2017 12:51 pm »
That seems reasonable, but I don't think we're still talking about molecular energies, albeit on the high end, rather than nuclear.
« Last Edit: 02/27/2017 01:35 pm by Proponent »

Offline gospacex

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Re: Metallic Hydrogen is real!
« Reply #84 on: 02/27/2017 01:11 pm »
if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds.

There is a very common mistake in the above description. "Breaking of bonds" of any bound system never releases any energy: it absorbs it. By definition, a "bound" system is one which has less energy than its constituent parts separated. Unbinding bound system takes energy.

The reactions which release energy either create bound system from parts (e.g. H->He fusion) or rearrange initial bound system(s) into final, more tightly bound system(s). Examples: H2+O2 -> H2O burning; U235+n -> Kr89+Ba144+2n fission.

Offline ppnl

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Re: Metallic Hydrogen is real!
« Reply #85 on: 02/27/2017 06:22 pm »
You don't need to combine it into a larger object, actually for it to be used as a fuel, you need to keep it to very tiny pellets.

And why do you assume that diamonds will explode every time?

No but to use it as anything other than rocket fuel you will need to combine it.

And I'm not assuming that the diamond will explode every time. But you will be using so many of them that even a small failure rate will make De Beers very happy.

Offline IRobot

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Re: Metallic Hydrogen is real!
« Reply #86 on: 02/27/2017 07:03 pm »
They are artificial diamonds, not natural:

Quote
But rather than natural diamond, Silvera and Dias used two small pieces of carefully polished synthetic diamond and treated them to make them even tougher.

http://news.harvard.edu/gazette/story/2017/01/a-breakthrough-in-high-pressure-physics/

Offline Stormbringer

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Re: Metallic Hydrogen is real!
« Reply #87 on: 02/27/2017 09:38 pm »
if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds.

There is a very common mistake in the above description. "Breaking of bonds" of any bound system never releases any energy: it absorbs it. By definition, a "bound" system is one which has less energy than its constituent parts separated. Unbinding bound system takes energy.

The reactions which release energy either create bound system from parts (e.g. H->He fusion) or rearrange initial bound system(s) into final, more tightly bound system(s). Examples: H2+O2 -> H2O burning; U235+n -> Kr89+Ba144+2n fission.
and yet exothermal chemical reactions release energy. what i was getting at there is that chemical reactions for matter with smaller bond lengths whether chemical or nuclear would release more energy because the energy in a bond is inversely proportional to the bond length scaling.

you took it from the other end of the scenario that it does take energy to break a bond in the case monopole atoms the energy of first ionization is calculated to be roughly that of an extreme high energy gamma ray or perhaps more.


But i was talking about the electronic bond and assume that the monopole matter can form analogous to normal matter and have both nucleonss and electron substitute particles ammenable to forming atoms and forming diverse elements and compounds. ( neverminding  the question of whether monopoles exist at all :)    )


From Orion's arm; a shared scifi universe that has a lot of hard sci mixed with some more fantastic elements. The bit that is hard sci/fi usually is often built on peer reviewed science article cites. Before their last site rebuild the cites for Monopole science was pretty good with 6 cites of peer reviewed papers. after the rebuild i cannot find the cite footnotes butthey may still bethere somewhere.


Quote
he smallest magatoms have diameters of 3E-19 m, 300 million times smaller than an atom of conventional matter. As a typical magatom is 10,000 times heavier than a typical conventional atom, magmatter's typical density is 1E33 kg/m3. Since force is energy per unit distance, the force needed to break a magchemical bond is larger than that needed to break an electronic chemical bond by a factor of the energy scaling (300 GeV / 13.7 eV) divided by the length scaling, or 7 million trillion (7E18). The strength of a material is usually defined as the force per unit area required to make the material fail. Since each magchemical bond can withstand 7E18 times greater force, and there are (300 million)2 times more bonds per unit area, the strength of magmatter is about 8E35 times greater than that of its normal matter equivalent.
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Offline Billium

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Re: Metallic Hydrogen is real!
« Reply #88 on: 09/13/2020 05:54 pm »
There is new work out metallic hydrogen from a French group who may have created it. https://www.nature.com/articles/d41586-020-00149-7

I was tipped off from a video in the Subject Zero Science YouTube channel.


Online edzieba

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Re: Metallic Hydrogen is real!
« Reply #89 on: 09/14/2020 05:57 pm »
Source paper appears to be here: https://doi.org/10.1038/s41586-019-1927-3
I may be misunderstanding, but Fig 2c does indiacte against metastabiltiy, at least under their test conditions: the rapid change in absorption characteristics reverses as pressure is released in a near-identical manner to pressure being applied.

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.
If metastable metallic Deuterium is created, and it is not named 'Duodec', then somebody has dropped the ball!

Offline sanman

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Re: Metallic Hydrogen is real!
« Reply #90 on: 09/18/2020 06:24 am »
There would be huge entropy pressure against such a material, though. There are no examples of this kind of degenerate matter in nature.

Offline Vahe231991

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Re: Metallic Hydrogen is real!
« Reply #91 on: 07/28/2023 03:13 am »
I found a recent paper suggesting that metallic hydrogen has probably been made from plastics:
https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.L022023

If the conclusion of this paper is taken seriously by rocket scientists, it would add ammunition to the case for metastable metallic hydrogen being a highly efficient rocket propellant because metastable metallic hydrogen has a theoretical specific impulse of up to 1700 seconds. A best bet would be for hundreds of thousands of tons of disposed plastic material to be used for the production of metallic hydrogen rocket fuel.
« Last Edit: 07/28/2023 02:24 pm by Vahe231991 »

Offline redneck

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Re: Metallic Hydrogen is real!
« Reply #92 on: 07/28/2023 09:13 am »
Interesting paper. Read the PDF. Even diluted to keep chamber temps in line, it would change space transportation dynamics. Even a Mars return could be affected by using the metallic hydrogen to heat in situ obtained CO2 or whatever is easiest to obtain. 

Edit.  All depends on costs and difficulty in real use.   
« Last Edit: 07/28/2023 09:38 am by redneck »

Online edzieba

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Re: Metallic Hydrogen is real!
« Reply #93 on: 07/28/2023 10:10 am »
I found a recent paper suggesting that metallic hydrogen has probably been made from plastics:
https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.L022023

If the conclusion of this paper is taken seriously by rocket scientists, it would add ammunition to the case for metastable metallic hydrogen being a highly efficient rocket propellant because metastable metallic hydrogen has a theoretical specific impulse of up to 1700 seconds. A best bet would be for hundred of thousands of tons disposed plastic materials to be used for the production of metallic hydrogen rocket fuel.
Note that the paper is not positing the creation of metastable metallic Hydrogen, the metallic Hydrogen exists transiently in the region immediately behind the shockwave passing through the polymer sample.

 

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