Aparently they created metalic hydrogen

[kunok]

http://www.nextbigfuture.com/2016/11/if-newly-created-metallic-hydrogen.html

We still don't know if is metastable but how good it would be to have.

Example rocket figures (the figures itself are in english) http://danielmarin.naukas.com/2016/11/08/cohetes-de-hidrogeno-metalico/#comment-406615

[softweir]

That's very interesting indeed! This is one to keep an eye on.

[Streetwind]

...Room temperature superconductor?! Step the hell back! That's not even funny to joke or speculate about

Seriously. If that happens, then rockets are going to be the least important benefactor. By orders of magnitude. The Nobel prize wouldn't suffice to express the importance of making such a thing practicable.

Ergo, chalk me up under "I'll believe it when I see it"

[Gaarst]

Link to the paper for those interested (and who can access it also): https://arxiv.org/abs/1610.01634

[p1t1o]

I've heard several people say "It could be metastable, we're not sure yet."

Is there any reason to expect it to be? My gut says that its going to need not a subtle reason, but an extremely compelling one.

Who in their right mind would expect something compressed to 5million bar to be stable at 1 bar?

I know that metastability is a thing but 5 million bar is one hell of a jump, I feel like its only talked about because it sounds cool.

[Benji13]

1 hour ago, p1t1o said:

I feel like its only talked about because it sounds cool.

Pun intended?

[Tullius]

1 hour ago, p1t1o said:

I've heard several people say "It could be metastable, we're not sure yet."

Is there any reason to expect it to be? My gut says that its going to need not a subtle reason, but an extremely compelling one.

Who in their right mind would expect something compressed to 5million bar to be stable at 1 bar?

I know that metastability is a thing but 5 million bar is one hell of a jump, I feel like its only talked about because it sounds cool.

Until now (and that is what that paper is all about), they only found something that looks like metallic hydrogen and even that fits the theories not very nicely.

Wikipedia has an article giving a few theories and results about metallic hydrogen (https://en.wikipedia.org/wiki/Metallic_hydrogen): There is one theory from 1968 that states that metallic hydrogen is a superconductor at room temperature.

[p1t1o]

46 minutes ago, Tullius said:

Until now (and that is what that paper is all about), they only found something that looks like metallic hydrogen and even that fits the theories not very nicely.

Wikipedia has an article giving a few theories and results about metallic hydrogen (https://en.wikipedia.org/wiki/Metallic_hydrogen): There is one theory from 1968 that states that metallic hydrogen is a superconductor at room temperature.

Thats all fine, Im fine with superconductivity, but why would anyone assume "it could be metastable"?

 

53 minutes ago, Benji13 said:

Pun intended?

Actually, no  

Now I feel UNDER PRESSURE to come up with an intended one...

 

**edit**

Did some searching around, almost all mentions of metastability were in the form of "...if it turns out to be metastable..." but there is one reference, to a 1972 paper from a Soviet physics journal which apparently has some calculations which predict metastability:

http://jetp.ac.ru/cgi-bin/dn/e_035_04_0783.pdf

This is an old paper, have the physics been updated since? Can anyone judge its quality or validity in present-day physics? Its a little above my pay-grade this one.

ITs also not clear whether or not "metastability" would actually mean that it would remain at its metallic density and retain its physical properties all the way down to 1atm, or whether it simply means "a bit more stable but still requiring colossal pressures".

 

*edit*

Found more science, maths a bit too intense for me here, not my area:

http://www.jetp.ac.ru/cgi-bin/dn/e_034_06_1300.pdf

Edited November 8, 2016 by p1t1o
avoid double post

[KSK]

Assuming that solid hydrogen is metastable, wouldn't any practical applications depend on how metastable it is? That superconducting hydrogen cable isn't going to be much use if a hefty sneeze is enough to trigger sublimation back to hydrogen gas.

[kerbiloid]

8 minutes ago, KSK said:

Assuming that solid hydrogen is metastable, wouldn't any practical applications depend on how metastable it is? That superconducting hydrogen cable isn't going to be much use if a hefty sneeze is enough to trigger sublimation back to hydrogen gas.

Now they can avoid cooling the cables down to absolute zero.
Now they just need a cable insulation to withstand 5 million bar.

[p1t1o]

13 minutes ago, kerbiloid said:

Now they can avoid cooling the cables down to absolute zero.
Now they just need a cable insulation to withstand 5 million bar.

If the cable goes along the bottom of the ocean you can take 1000bar off that, much easier now!

[Scotius]

38 minutes ago, KSK said:

Assuming that solid hydrogen is metastable, wouldn't any practical applications depend on how metastable it is? That superconducting hydrogen cable isn't going to be much use if a hefty sneeze is enough to trigger sublimation back to hydrogen gas.

Very good question. And i wouldn't want to be anywhere close to such event. Enough dV to send single stage rocket plus useful payload to the Moon contained in a single tank? That's A LOT of energy in one place.

[magnemoe]

21 minutes ago, Scotius said:

Very good question. And i wouldn't want to be anywhere close to such event. Enough dV to send single stage rocket plus useful payload to the Moon contained in a single tank? That's A LOT of energy in one place.

Yes, one issue here is how stable is metastable? nitroglycerin is also metastable, some stuff mentioned in ignition makes nitroglycerin look child safe. 
 

[Hast5250]

On 11/8/2016 at 3:14 AM, Streetwind said:

...Room temperature superconductor?! Step the hell back! That's not even funny to joke or speculate about

Seriously. If that happens, then rockets are going to be the least important benefactor. By orders of magnitude. The Nobel prize wouldn't suffice to express the importance of making such a thing practicable.

Ergo, chalk me up under "I'll believe it when I see it"

Pyrolitic carbon is a superconductor at room temperature.

[Streetwind]

21 minutes ago, Hast5250 said:

Pyrolitic carbon is a superconductor at room temperature.

Hmmm. Is it? I looked it up, and there seems to be no mention of superconductivity anywhere, regardless of temperature. Do you have a better source, maybe?

[p1t1o]

28 minutes ago, Hast5250 said:

Pyrolitic carbon is a superconductor at room temperature.

 

5 minutes ago, Streetwind said:

Hmmm. Is it? I looked it up, and there seems to be no mention of superconductivity anywhere, regardless of temperature. Do you have a better source, maybe?

No, it most certainly isn't! Room temperature superconductors represent almost a "holy grail", "Pyrolytic" carbon is essentially identical to graphite, for most intents and purposes. 

It does have some magnetic properties which allow it to be used in magnetic levitation experiments though, which are often associated with superconductivity, perhaps this is where the confusion arose?

Edited November 25, 2016 by p1t1o

[Hast5250]

15 minutes ago, p1t1o said:

 

No, it most certainly isn't! Room temperature superconductors represent almost a "holy grail", "Pyrolytic" carbon is essentially identical to graphite, for most intents and purposes. 

It does have some magnetic properties which allow it to be used in magnetic levitation experiments though, which are often associated with superconductivity, perhaps this is where the confusion arose?

Hmmmm, I thought it was superconducting. oh well.

[p1t1o]

6 minutes ago, Hast5250 said:

Hmmmm, I thought it was superconducting. oh well.

At the current time, room temp superconductors are still hypothetical, and you can guarantee that you would hear about it if a viable example was discovered because it would be an extremely disruptive technology, in that it could revolutionise a great many fields of research, not to mention the advantages that could be brought to various types of engineering.

It would only be a slightly bigger deal if someone announced they had discovered artificial gravity or a warp drive! (Ok, that might be overstating it a little  )

 

Edited November 25, 2016 by p1t1o

[Hast5250]

okay...

[Gaarst]

1 hour ago, p1t1o said:

It would only be a slightly bigger deal if someone announced they had discovered artificial gravity or a warp drive! (Ok, that might be overstating it a little  )

You can make use of superconductors in your everyday life. I don't know if neutralising gravity in your living room would be very useful.

[kunok]

2 hours ago, p1t1o said:

a viable example was discovered because it would be an extremely disruptive technology

If its easy to manufacture, because if not it would be a niche product like the current cryogenics superconductors. People tend to forget that

[K^2]

On 11/8/2016 at 4:46 AM, KSK said:

Assuming that solid hydrogen is metastable, wouldn't any practical applications depend on how metastable it is? That superconducting hydrogen cable isn't going to be much use if a hefty sneeze is enough to trigger sublimation back to hydrogen gas.

Less sublimation, more a violent explosion. Even without oxidizer, metallic hydrogen stores a huge amount of energy which gets released when converted back to gaseous form. And since this first explosion is going to be sufficient to rupture pretty much any enclosure one might have for it, it's going to mix with oxygen in atmosphere and produce a nice fireball to round off the effect.

Nonetheless, even though this would certainly dramatically reduce the list of viable applications, regardless of how volatile it is, if there is some form of metastability, we are guaranteed to find uses for it. It's just that cool of a material.

Mtastability is the crux, though. We have known that it can be turned metallic for a long time. We know that it will have a lot of interesting properties, including high temperature superconductivity. But all of this is useless information, outside of explaining Jupiter's magnetic field, unless metastability is confirmed. And theoretical evidence for it is not particularly strong.

[p1t1o]

On 11/25/2016 at 6:08 PM, Gaarst said:

You can make use of superconductors in your everyday life. I don't know if neutralising gravity in your living room would be very useful.

You cant think of any uses? I can...

(moving heavy furniture you dirty animal!)

On 11/25/2016 at 7:00 PM, kunok said:

If its easy to manufacture, because if not it would be a niche product like the current cryogenics superconductors. People tend to forget that

True dat, though given time hard-to-manufacture almost inevitably becomes easy-to-manufacture, even if it takes a hundred years.