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pujjad

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The British mini nuclear fusion reactor that works

thetimes.com
8 ポイント·投稿者 pujjad·昨年·3 コメント

Could this startup's compact nuclear reactors revolutionize cancer detection?

techcrunch.com
3 ポイント·投稿者 pujjad·昨年·5 コメント

With historic explosion, a long sought fusion breakthrough

science.org
2 ポイント·投稿者 pujjad·4 年前·0 コメント

What If You Tried to Swallow a Whole Cloud?

wired.com
2 ポイント·投稿者 pujjad·4 年前·0 コメント

Bash Pitfalls

mywiki.wooledge.org
106 ポイント·投稿者 pujjad·4 年前·32 コメント

Juno reveals deep 3D structure of Jupiter’s storms

theconversation.com
1 ポイント·投稿者 pujjad·5 年前·0 コメント

コメント

pujjad
·昨年·議論
[flagged]
pujjad
·昨年·議論
And yes you're right, it's a neutron generator. They don't claim to ever achieving break even, or even power surplus. No fusion startup will ever do in my view. Combining that neutron generator with active material, now we're talking. That's a sub critical ultra compact hybrid reactor, which becomes super critical by pressing a button. And sub critical again with another press. That's the future and the reason why some folks at NASA want to get hold of one for their future space mission
pujjad
·昨年·議論
Huge difference. Fusors are just Inertial electrostatic confinement fusion devices. This one here adds lattice confinement fusion to it (see NASA Glenn Research two Phys Rev C papers in 2023), ie you reach fuel densities 6 to 8 orders of magnitudes higher than in a plasma as you exploit electron screening in your metal lattice, plus binary packing in specific metal alloys. Anyone can build a fusor in a kitchen, but these guys combine two entirely different fusion mechanisms (IEC+LFC) which hasn't been done before. That way you get minimum 1E11 DT neutrons/s at source, and even higher fluxes once you start optimising the materials involved. A hard 14 MeV DT neutron generator with that high flux? A golden opportunity for testing future materialsand electronics in a harsh fusion environment.

A fusor does 1E6 n/s at best, and that'd be 2.45 MeV DD neutrons only, because obtaining a Tritium license is not trivial.
pujjad
·3 年前·議論
LAMMPS: https://lammps.org/ - MD Simulator (Sandia Labs)

GEANT4: https://geant4.web.cern.ch/ Monte Carlo code for particles through matter (CERN)

Moose & MFEM are great projects and important in itself, but not relevant in the nuclear physics domain. Software which is remains export-restricted for good reasons. Here a list for the curious mind:

FISPACT-II: https://fispact.ukaea.uk/ Inventory & Source term (UKAEA)

MCNP: https://mcnp.lanl.gov/ - Monte Carlo code (LANL)

SERPENT: https://serpent.vtt.fi/serpent/ - Neutronics (VTT)

VASP: https://www.vasp.at/ - Ab Initio DFT (U Vienna)

TRANSURANUS: https://data.jrc.ec.europa.eu/collection/transuranus - Nuclear Fuel Performance Code (EU/JRC)

BISON: https://bison.inl.gov - Next-Gen Nuclear Fuel Performance Code (INL)

(edit: formatting)
pujjad
·3 年前·議論
The article mmentions Moose, MFEM, OpenMC, but the really good stuff relevant for us nuclear physicist I would expect being talked about aren't mentioned: Bison, Transuranus, Marmot, Serpent, Vasp, Rattlesnake, Fispact.

On the open source open access side I'm missing Lammps or Geant4.
pujjad
·4 年前·議論
It's an argument pro two-time scales and against two dimensional time just by looking at what math says about partially ordered sets. R^2 is clearly not partially ordered as opposed to R^1.
pujjad
·4 年前·議論
In a world with two time dimensions there would be no such thing as causality: with a, b \in R^2 (the field of real numbers), a<b doesn't make sense, because two events can have the same distance from (0,0) but different angle \phi (modulo orientation of chosen frame of reference), and therefore I wouldn't be able to distinguish between past and future events in general. Causality breaks down.

Propagating along a 1D trajectory (ie flow of time) would then be along a 2D "trajectory" through which I would experience indefinitively many events at once, unclear which one impacts on which others. But clearly I perceive me writing this post "right now", and am about to push the send button..