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Hold on how does that work?
I have had a sort of sci-fi idea that sufficiently sensitive gravitational field measurements coukd detect the passing of submarines (I am not sure on the maths tbh) - which would render a lot of nuclear strategy moot.
Just need to get a grasp on the maths
Earlier quoted context omitted.
It means getting the nucleus to absorb a certain energy above its ground state. Since it is a quantum object, it can only absorb/emit energy in very specific amounts at once (“quanta”). The details of how the nucleus manifests that extra energy are complicated, but you can imagine it as like, picking up a certain vibrational frequency.
But then what happens? Does it expel an electron/release energy etc.?
>>> For example, the Earth's gravitational field could be analyzed so precisely that it could provide indications of mineral resources Hold on how does that work? I have had a sort of sci-fi idea that sufficiently sensitive gravitational field measurements coukd detect the passing of submarines (I am not sure on the maths tbh) - which would render a lot of nuclear strategy moot. Just need to get a grasp on the maths
Gravitational Detection of Submarines, PM Moser 1989
Earlier quoted context omitted.
Thorium-229 has two energy states. A ground state, and an excited isometric state. The laser is used to transition the nucleus from the ground state to the excited isometric state.
Isometric? Like, is the nucleus gaining a virtual proton or something?
>>> For example, the Earth's gravitational field could be analyzed so precisely that it could provide indications of mineral resources Hold on how does that work? I have had a sort of sci-fi idea that sufficiently sensitive gravitational field measurements coukd detect the passing of submarines (I am not sure on the maths tbh) - which would render a lot of nuclear strategy moot. Just need to get a grasp on the maths
https://apps.dtic.mil/sti/pdfs/AD1012150.pdf Gravitational Detection of Submarines, PM Moser 1989
Now how the heck do you generate ~148.38nm light with a narrow linewidth? Their approach using four-wave mixing inherently results in short pulses. .. and given that it decays through gamma emission, does this mean we could now build an optically pumped gamma ray laser?
The gamma emission would have to re-excite other atoms in a cascade to create a laser. Since the exciting energy is UV, not gamma => no cascade amplification. A "wavelength converter" might be possible. PS: Are you sure it's gamma emission? That takes more energy than the exciting UV photon.
Apparently it is neither:
Decay of the 229Th isomeric state of the neutral thorium atom occurs predominantly by internal conversion (IC) with emission of an electron
https://www.nature.com/articles/nature17669
https://en.wikipedia.org/wiki/Internal_conversion
This is pretty weird. You shine UV light (with exactly the right wavelength) on 229Th, and it spits out electrons. But not like the photoelectric effect, where the electrons stop as soon as you turn off the light. No no. The Thorium keeps spitting out an exponentially-decaying stream of electrons for hours after you stop illuminating it.
Almost like an exponentially-discharging solar-powered current source (for a very specific wavelength of "solar").
Earlier quoted context omitted.
It means getting the nucleus to absorb a certain energy above its ground state. Since it is a quantum object, it can only absorb/emit energy in very specific amounts at once (“quanta”). The details of how the nucleus manifests that extra energy are complicated, but you can imagine it as like, picking up a certain vibrational frequency.
With enough absorptions, can the nucleus tear itself apart (i.e. fission) ?
[0] https://en.wikipedia.org/wiki/Photofission [1] https://en.wikipedia.org/wiki/Isotopes_of_tantalum#Tantalum-...
For example, the Earth's gravitational field could be analyzed so precisely that it could provide indications of mineral resources Resources companies are salivating
> If the wavelength of the laser is chosen exactly right ... then maybe a special atomic nucleus could be manipulated with a laser, namely thorium-229. On November 21, 2023, the team was finally successful: the correct energy of the thorium transition was hit exactly, the thorium nuclei delivered a clear signal for the first time. So what's the wavelength? I felt like the article left me hanging. The answer is: 148.3…
Missing out on the magic number does seem like a bit of a problem, but really the expectations on the audience are already quite low. That number could easily turn out to be worth more than a trillion dollars to humanity at large, but I'd bet most readers just think of it as a party factoid.