The First Nuclear Clock Will Test if Fundamental Constants Change | Quanta Magazine
www.quantamagazine.org
An ultra-precise measurement of a transition in the hearts of thorium atoms gives physicists a tool to probe the forces that bind the universe.

An ultra-precise measurement of a transition in the hearts of thorium atoms gives physicists a tool to probe the forces that bind the universe.

  • shortwavesurferEnglish
    25·
    3 months ago

    So, I’m not quite sure I understand. I know that they use CZM atoms for atomic clocks, and they are extremely accurate. So, will this be used for atomic clocks, too? Or is it more accurate? Or is this for something totally different entirely? It appears to me as though this is something different entirely. But I don’t see why it could not be used for an atomic clock if it’s even more accurate than Seism.

    • gasgiant@lemmy.mlEnglish
      26·
      3 months ago

      My understanding is that current atomic clocks work on changing the state of whole atoms.

      Whereas this new method changes the state of part of the nucleus of an atom.

      Basically smaller is more precise. However given that current atomic clocks are one second out over something like a billion years I’ve no idea what benefit this extra preciseness will give us.

      We’ll probably start noticing really weird shit when we look at time that precisely. That’s generally what’s happened when we get into the quantum scale of things.

      • monkeyslikebananas2@lemmy.worldEnglish
        142·
        3 months ago

        Yeah the simulation breaks down when you reach quantum scales. The engine will start trying to render things it doesn’t know how to render and things just kind of fall apart (particle-wave duality and all that).

        If you stay in the macro scale there are efficient functions that handle the world physics very well.

        I’m most impressed with the concurrency of the simulation than anything else. But tbqh it could all be running on a single thread and we probably wouldn’t be able to tell. Again, unless we get to the quantum scales.

        • randon31415@lemmy.worldEnglish
          31·
          3 months ago

          That fact that it could be a simulation hints at the fact that there is an underlying set of rules that could be used to generate that simulation. Those underlying set of rules could also be considered the most fundamental laws that govern the universe.

        • JackGreenEarth@lemm.eeEnglish
          41·
          3 months ago

          Now I know you’re from somewhere in the world where they don’t pronounce Z like zed!

          Aside though, the rest of that is great dictation, what app are you using?

            • JackGreenEarth@lemm.eeEnglish
              1·
              3 months ago

              Ah, thanks!

              I’m using Sayboard which integrates well with Heliboard, but has lower quality than yours it seems. Its properly FOSS though, unlike Futo apps.

              • shortwavesurferEnglish
                2·
                3 months ago

                Going to have a look at sayboard now. I’m not after a full keyboard or anything. I just need the dictation because I use the keyboard that comes with lineage or graphene, which I believe is just the AOSP keyboard.

                Edit: okay i am giving it a try so far it seems like it works well enough but i definitely wish it had a tone to let you know that the recording had started. It also appears to not work every time like it should. Also i don’t seem to be able to find a space bar in order to dictate a new sentence once i’m done with one which is somewhat irritating

          • astrsk@fedia.io
            1·
            3 months ago

            Actually, I just checked my voice assistant, it got CZM from “see-zed-em” just fine. American English settings on my phone with a PNW grey accent. In fact, saying “see-zee-em” failed more for me, thinking I said CCM or Cesium multiple times.

            • Confused_Emus@lemmy.dbzer0.comEnglish
              5·
              3 months ago

              That’s what they were saying. We know OP doesn’t say zed because you’d expect to get “CZM” saying it that way. We know OP says zee because the dictation mistakenly typed CZM instead of the desired Cesium - the atom used in atomic clocks.

    • Drunemeton@lemmy.worldEnglish
      13·
      3 months ago

      It’s that t-229 can have its nucleus excited using far less energy than regular atomic clock nuclei.

      That leads to ultra precise excitation using wavelengths that cancel out some of the fundamental forces within the atom.

      That leads to us being able to monitor at a trillion to one ratio those forces based, in part, on mathematical ‘constants.’ In the excited state we can measure if there’s even the smallest variance in force, which in turn may mean that some ‘constants,’ aren’t.

      However the real testing of that is in the future as they estimate that a 10 trillion to one ratio is needed.

      Theory described a door, research defined the door and possibly what’s behind it, and experimentation just opened the door.

    • mark3748@sh.itjust.worksEnglish
      11·
      3 months ago

      The Idaho researchers observed that reversing the intrinsic angular momentum, or “spin,” of thorium-229’s outermost neutron seemed to take 10,000 times less energy than a typical nuclear excitation. The neutron’s altered spin slightly changes both the electromagnetic and strong forces, but those changes happen to cancel each other out almost exactly. Consequently, the excited nuclear state barely differs from the ground state. Lots of nuclei have similar spin transitions, but only in thorium-229 is this cancellation so nearly perfect.

      Basically, thorium-229 can be excited by conventional lasers instead of gamma rays. Instead of millions of electron volts, it takes less than 10, which means it’s more reliable and more precise.