Tulsi Gabbard says Iran could produce nuclear weapons "within weeks", months after she testified before Congress that the country was not building them. The US Director of National Intelligence said her March testimony - in which she said Iran had a stock of materials but was not building these weapons - had been taken out of context by "dishonest media".
  • ddh@lemmy.sdf.orgEnglish
    43·
    18 hours ago

    Depends what you mean by fusion energy, but fairly recently ignition has been achieved and breakeven surpassed.

    In December 2022, the National Ignition Facility, or NIF, an inertial confinement facility, reached Q = 1.54 with a 3.15 MJ output from a 2.05 MJ laser heating. NIF achieved ignition seven times. The highest gain as of 2025 of Q = 4.13 yielded 8.6 MJ from 2.08 MJ of laser energy.

    https://en.wikipedia.org/wiki/Fusion_energy_gain_factor

    • sp3ctr4l@lemmy.dbzer0.comEnglish
      3·
      14 hours ago

      While that quote alone, and the NIF’s results are very impressive and promising…

      The beginning of that wiki page says you actually have to hit more like a Q of 5 before you get something that can power its own heat managment and other operating systems as well, to stand a chance at being sustainable.

      The other big, missing piece of context is:

      The NIF facility’s impressive results come from shooting about 200 lasers at a tiny capsule, which heats it so fast it becomes a plasma and undergoes fusion, and then the energy released is captured.

      But… this is not like a toroidal reactor, that, if it got high enough Q, could just keep running and producing energy in net.

      This is more like firing an artillery canon that needs to be carefully and manually reloaded.

      It is not a continuous, on going process… the position of the capsule must be perfectly aligned to where all the lasers convergently aim at, and its a burst, with a reload time.

      That and the capsule (technically a ‘hohlraum’) itself is… making one is a massively intensive and complex process.

      The actual fusion fuel part of the pellet has to be encased in a diamond, and then gold, and it has to be like nano scale perfect.

          • GreyEyedGhost@lemmy.ca
            1·
            10 hours ago

            But your statement implies it’s some impossible feat, and not simply a lack of funding, and maybe it is impossible, but how would we know if we never properly fund it? Moreover, you associated it with a propaganda reference, and I’m not even sure what you’re getting at there.

            • Anomalocaris@lemm.eeOP
              11·
              10 hours ago

              just saying it was an example of one of those things that are always a free years in the future. like flying cars, which as a society, gave up on