4 ms·

My first reaction to the headline was "I wonder how many teslas the magnets they're using to keep it together are?"

by xxpor 5y ago

colechristensen 5y ago
It’s essentially impossible to make an electron-only substance. The highest density normal-matter stars (white dwarfs) are kept from collapsing with the force of electric repulsion in atoms and they do collapse by proton-electron collision and conversion into neutrons. From Feynman: If you were standing at arm’s length from someone and each of you had one percent more electrons than protons, the repelling force would be incredible. How great? Enough to lift the Empire State Building? No! To lift Mount Everest? No! The repulsion would be enough to lift a “weight” equal to that of the entire earth!
- eloff 5y ago
  Wow! That is a great visualization of how strong the forces are. It's incredibly strong, I had no idea
- MaxikCZ 5y ago
  So we only need to push a lot of electrons into some matter and get maglev trains without superconductors?
  - colechristensen 5y ago
    Not really. “only”, no. Trying to levitate trains with static charge would introduce all kinds of hard problems, some easy to imagine, some probably would take a lot of engineering to discover. The electric field would be hard to contain just under the train, the charge would really really try hard to find somewhere else to be, there would be some crazy ionization of the air going on… flying a kite in a thunderstorm would probably be quite safe by comparison to being close to such an apparatus.
- a1369209993 5y ago
  > If you were standing at arm's length from someone and each of you had one percent more electrons than protons[[0]] The latent energy of electromagnetic repulsion between the two of you (never mind between the parts of each of your bodies) would be a bit more than ((1%*80kg/2amu*electroncharge)^2 coulombconst / meter), or on the order of a megaton. Not megaton tnt, a megaton of just energy (comparable to a million tons of antimatter). 0: https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-were-1-charged/ https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-...
- redis_mlc 5y ago
  Gee, I wonder when and why he made that calculation ...

My first reaction to the headline was "I wonder how many teslas the magnets they're using to keep it together are?"

by xxpor 5y ago

My first reaction to the headline was "I wonder how many teslas the magnets they're using to keep it together are?"

It’s essentially impossible to make an electron-only substance. The highest density normal-matter stars (white dwarfs) are kept from collapsing with the force of electric repulsion in atoms and they do collapse by proton-electron collision and conversion into neutrons. From Feynman: If you were standing at arm’s length from someone and each of you had one percent more electrons than protons, the repelling force would be incredible. How great? Enough to lift the Empire State Building? No! To lift Mount Everest? No! The repulsion would be enough to lift a “weight” equal to that of the entire earth!

eloff 5y ago
Wow! That is a great visualization of how strong the forces are. It's incredibly strong, I had no idea
MaxikCZ 5y ago
So we only need to push a lot of electrons into some matter and get maglev trains without superconductors?
- colechristensen 5y ago
  Not really. “only”, no. Trying to levitate trains with static charge would introduce all kinds of hard problems, some easy to imagine, some probably would take a lot of engineering to discover. The electric field would be hard to contain just under the train, the charge would really really try hard to find somewhere else to be, there would be some crazy ionization of the air going on… flying a kite in a thunderstorm would probably be quite safe by comparison to being close to such an apparatus.
a1369209993 5y ago
> If you were standing at arm's length from someone and each of you had one percent more electrons than protons[[0]] The latent energy of electromagnetic repulsion between the two of you (never mind between the parts of each of your bodies) would be a bit more than ((1%*80kg/2amu*electroncharge)^2 coulombconst / meter), or on the order of a megaton. Not megaton tnt, a megaton of just energy (comparable to a million tons of antimatter). 0: https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-were-1-charged/ https://gravityandlevity.wordpress.com/2013/05/22/what-if-i-...
redis_mlc 5y ago
Gee, I wonder when and why he made that calculation ...