Atomic nucleus excited with laser: A breakthrough after decades
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Re: Atomic nucleus excited with laser: A breakthrough after decades
#2> This makes it possible to combine two areas of physics that previously had little to do with each other: classical quantum physics and nuclear physics.
Is quantum physics now considered part of classical physics? If so then man, time flies!
Re: Atomic nucleus excited with laser: A breakthrough after decades
#3> This makes it possible to combine two areas of physics that previously had little to do with each other: classical quantum physics and nuclear physics. Is quantum physics now considered part of classical physics? If so then man, time flies!
There is a big difference between "classical" quantum mechanics (about 100 years old now!) and quantum field theory (~50 years old). Maybe that's what they mean?
Re: Atomic nucleus excited with laser: A breakthrough after decades
#4From the paper, the light is UV-C at around 140nm or 8.4 eV. But it has to be very precisely the right energy to cause the transition, since nuclear states don’t have any place to dump excess energy to.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#5The measurement was already confirmed by a different group: https://arxiv.org/abs/2404.12311
This is important since impurities in the crystals used lead to all kinds of fluorescence that could be mistaken for a signal from the Thorium ions. Now two groups have seen exactly the same signal in different Thorium-doped crystals which is very covincing that they have found the actual nuclear transition.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#6> This makes it possible to combine two areas of physics that previously had little to do with each other: classical quantum physics and nuclear physics. Is quantum physics now considered part of classical physics? If so then man, time flies!
I think they want to convey that nucleus is a really weird place so quantum physics of everything else is classical by comparison.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#7> This makes it possible to combine two areas of physics that previously had little to do with each other: classical quantum physics and nuclear physics. Is quantum physics now considered part of classical physics? If so then man, time flies!
Classical there is used in the sense of “non relativistic”.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#8> This makes it possible to combine two areas of physics that previously had little to do with each other: classical quantum physics and nuclear physics. Is quantum physics now considered part of classical physics? If so then man, time flies!
There is a big difference between "classical" quantum mechanics (about 100 years old now!) and quantum field theory (~50 years old). Maybe that's what they mean?
When I was at university about 25 years ago, QM was about electron transition energies, with QED being a refinement of that for things like fine structure. In experimental HEP you had QCD and quark gluon plasma which informs things like the LHC experiments at CERN.
IIRC nuclear physics was largely phenomenological with a lot of observations that had simple models fit to them without being able to reduce those to the particle physics models. This might be about establishing a link between the phenomenological nuclear models and the fundamental QM models.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#9> 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: 148.3821 nm
Yes, I admit that it's meaningless to me. It's sort of like a big news story announcing that Malaysia Airlines MH-370 has been located somewhere in the world's oceans, but not saying where because a number like 148.3821 km SSE of the Cocos Islands is going to be meaningless to most people.
Re: Atomic nucleus excited with laser: A breakthrough after decades
#10What does "exciting a nucleus" mean?