5 ms·

An implosion-type nuclear weapon can compress matter to some multiple of the density of osmium. This isn't useful for USPS box packaging; I just think it's nea

An implosion-type nuclear weapon can compress matter to some multiple of the density of osmium. This isn't useful for USPS box packaging; I just think it's neat. edit: Also, inertial confinement fusion plasmas go up to about 1,000 g/cm³, https://aip.scitation.org/doi/full/10.1063/5.0008231 https://aip.scitation.org/doi/full/10.1063/5.0008231 ("Unified first-principles equations of state of deuterium-tritium mixtures in the global inertial confinement fusion region")

andersco 5y ago
Thanks for that tip. I am about to ship an implosion-type nuclear device and my first thought was if I could use a USPS flat rate box.
- m463 5y ago
  Be careful, the shipping rules are tricky. For example, you need to compress the implosion-type nuclear device with another implosion-type nuclear device first to get it to fit in the box.
  - a4isms 5y ago
    "It's implosion-type devices all the way out."
ilyagr 5y ago
Can this overcompressed material continue to exist at room temperature and pressure? It would be remarkable, but I guess it's hard to imagine how that could work.
- bell-cot 5y ago
  Not really. But if you ship it sufficiently fast, the en-transit expansion won't be enough to matter.
  - ilyagr 5y ago
    I guess if I can get USPS to accept the parcel quickly enough, what happens afterwards is their problem. I'm sure they won't mind. In fact, if the parcel is - er - damaged while in their care, the USPS will owe me. They better rush.
    - b112 5y ago
      I worked on this a bit, as a joke. A sex doll, in a box, with a small helium tank. I wanted a friend to open the box, be scared by the air/hissing sound, back away, and before he could react? Sex doll floats to the 12 foot ceiling in his office. I had issues with the trigger, it deploying correctly, tried it a dozen times and gave up. My other concern was it mistakely deploying while in transit with the post office.
- perihelions 5y ago
  That's a great question. There's solid phases you can create at extreme pressure that remain stable or metastable at STP, like the diamond allotrope of carbon. I don't know of any examples that retain a high density at low pressure. Is it possible for something like that to exist? There was a suggestion that hydrogen metal could be metastable at low pressure -- it would be much denser than molecular hydrogen -- but it looks like that's controversial: https://en.wikipedia.org/wiki/Metallic_hydrogen https://en.wikipedia.org/wiki/Metallic_hydrogen edit: Turns out diamond is ~70% denser than other forms of carbon, so that's sort of an example. Though its density is pretty low in absolute terms (~3.5 g/cm³). https://en.wikipedia.org/wiki/Carbon https://en.wikipedia.org/wiki/Carbon
  - ilyagr 5y ago
    Diamonds are a great example!
    - Retric 5y ago
      Especially because they’re slightly unstable at STP and will eventually decay, it’s just slow enough to only be relevant on geologic timescales.
- colechristensen 5y ago
  If there was a material which could handle the internal stress, sure. That material probably doesn't exist. Like a balloon exists at STP despite being internally at higher pressure, but balloons also pop. Tempered glass also exists and significantly higher pressure and likewise explodes. Often metal structures will retain some stress (sometimes quite high) after manufacture. The amount of energy released at some of those other materials if they had the magical property of staying together... would be terrifying if popped.
s1artibartfast 5y ago
I'm guessing that is a value for a hyper localized volume of the plasma

andersco 5y ago

Thanks for that tip. I am about to ship an implosion-type nuclear device and my first thought was if I could use a USPS flat rate box.

m463 5y ago
Be careful, the shipping rules are tricky. For example, you need to compress the implosion-type nuclear device with another implosion-type nuclear device first to get it to fit in the box.
- a4isms 5y ago
  "It's implosion-type devices all the way out."

ilyagr 5y ago

Can this overcompressed material continue to exist at room temperature and pressure? It would be remarkable, but I guess it's hard to imagine how that could work.

bell-cot 5y ago
Not really. But if you ship it sufficiently fast, the en-transit expansion won't be enough to matter.
- ilyagr 5y ago
  I guess if I can get USPS to accept the parcel quickly enough, what happens afterwards is their problem. I'm sure they won't mind. In fact, if the parcel is - er - damaged while in their care, the USPS will owe me. They better rush.
  - b112 5y ago
    I worked on this a bit, as a joke. A sex doll, in a box, with a small helium tank. I wanted a friend to open the box, be scared by the air/hissing sound, back away, and before he could react? Sex doll floats to the 12 foot ceiling in his office. I had issues with the trigger, it deploying correctly, tried it a dozen times and gave up. My other concern was it mistakely deploying while in transit with the post office.
perihelions 5y ago
That's a great question. There's solid phases you can create at extreme pressure that remain stable or metastable at STP, like the diamond allotrope of carbon. I don't know of any examples that retain a high density at low pressure. Is it possible for something like that to exist? There was a suggestion that hydrogen metal could be metastable at low pressure -- it would be much denser than molecular hydrogen -- but it looks like that's controversial: https://en.wikipedia.org/wiki/Metallic_hydrogen https://en.wikipedia.org/wiki/Metallic_hydrogen edit: Turns out diamond is ~70% denser than other forms of carbon, so that's sort of an example. Though its density is pretty low in absolute terms (~3.5 g/cm³). https://en.wikipedia.org/wiki/Carbon https://en.wikipedia.org/wiki/Carbon
- ilyagr 5y ago
  Diamonds are a great example!
  - Retric 5y ago
    Especially because they’re slightly unstable at STP and will eventually decay, it’s just slow enough to only be relevant on geologic timescales.
colechristensen 5y ago
If there was a material which could handle the internal stress, sure. That material probably doesn't exist. Like a balloon exists at STP despite being internally at higher pressure, but balloons also pop. Tempered glass also exists and significantly higher pressure and likewise explodes. Often metal structures will retain some stress (sometimes quite high) after manufacture. The amount of energy released at some of those other materials if they had the magical property of staying together... would be terrifying if popped.

s1artibartfast 5y ago

I'm guessing that is a value for a hyper localized volume of the plasma