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Atomic nucleus excited with laser: A breakthrough after decades

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Re: Atomic nucleus excited with laser: A breakthrough after decades

#161

Post by blincoln »

JanisErdmanis wrote: post #151
btilly wrote: post #110

Earlier quoted context omitted.

Yes, but a better clock means more precise measurements, means we can locate smaller masses to higher precision.

The problem is that the planet could be hollow and produce the same gravitational measurements on the surface and outside. It needs to be coupled with a model that introduces constraints for the inverse problem to be defined.

Since mining is only concerned with material that's within maybe 0.1% of the distance from the surface to the core, seems like you'd just need to move the sensor around and make sure the signal changes about where you'd expect for a mass of X Kg at a depth of Y meters instead of a supermassive chunk of dense material much deeper. Or, to put it another way, build a grid map of the area and subtract any background signal. Would that not work for some reason?

Re: Atomic nucleus excited with laser: A breakthrough after decades

#162

Post by [deleted] »

fsh wrote: post #5

The 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.

[deleted]

Re: Atomic nucleus excited with laser: A breakthrough after decades

#163

Post by vonzepp »

airstrike wrote: post #121
tzs wrote: post #119

Earlier quoted context omitted.

Note: I will use the term "soccer" for the most common football of Europe, "Association football", and "football" for American football. And before anyone says that soccer fields should be called "pitches" not "fields" I will note that FIFA's "Laws of the Game" call it "field" 184 times. They only mention "pitch" in the glossary where the heading for "field" is "Field of play (pitch)". Generally you want to use Ameri…

> I will use the term "soccer" for the most common football of Europe, "Association football", and "football" for American football. I appreciate your valiant efforts but to my mind this is extra confusing because "soccer" is short for "association football" Time to rename American Football to "handegg" once and for all. Ok, ok, I'll settle for "American Rugby"

Or just American Handball

Re: Atomic nucleus excited with laser: A breakthrough after decades

#164

Post by javajosh »

MilStdJunkie wrote: post #149

When you stop and look at QCD in the big picture, it's sort of shocking how little we know - like, really, really know - about the internal structure of the proton, or even the nucleon! It's the curse of "probing" with massive energies. No one's a hundred percent certain of whether they're detecting something that's actually there - like there there - or whether they're looking at by-product of enormous collision ene…

Yeah and maybe we could do GR experiments on a table top. Gravity goes as 1/r^2 so a small r might make the mass terms irrelevant, and you could check GR in various ways [1] especially Shapiro delay[2]. This would, in turn, give a way to probe quantum gravity effects.

1 - https://en.wikipedia.org/wiki/Tests_of_general_relativity

2 - https://en.wikipedia.org/wiki/Shapiro_time_delay

Re: Atomic nucleus excited with laser: A breakthrough after decades

#165

Post by ethbr1 »

beretguy wrote: post #115
pmayrgundter wrote: post #76

Earlier quoted context omitted.

Nice to hear the octave relation used! "blue above visible blue" is a good name.. hmm, a little web tool to name these would be neat ;)

> "blue above visible blue" Good name for a rock band. Or some tv series.

Joni Mitchell - Blue (Blue)

https://m.youtube.com/watch?v=MvR7Dkg4NQU&t=820s

Re: Atomic nucleus excited with laser: A breakthrough after decades

#166

Post by ChuckMcM »

fsh wrote: post #5

The 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.

Thanks for that, I wondered if it had been confirmed.

I am always in awe of folks who come into the lab every day and work on figuring out the one thing. I envy that level of focus.

Re: Atomic nucleus excited with laser: A breakthrough after decades

#167

Post by omnicognate »

denton-scratch wrote: post #122
emblaegh wrote: post #7

Earlier quoted context omitted.

Classical there is used in the sense of “non relativistic”.

I thought relativistic quantum physics was not a thing (yet).

Special vs general. Quantum field theory is special relativistic and quantum mechanical. The grand unified theory stuff is about uniting general relativity and quantum mechanics.

Re: Atomic nucleus excited with laser: A breakthrough after decades

#168

Post by nebben64 »

limbicsystem wrote: post #69
yread wrote: post #25

Is there some direct application? Like using the excitation states of different atoms for storing information?

I >think< that this will enable more accurate magnetometers (see OPM-MEG and atomic clock magnetometers). Which can be used, among other things, for measuring neuronal activity.

Can you explain your reply a bit; how will MEG tech evolve from this breakthrough?

Re: Atomic nucleus excited with laser: A breakthrough after decades

#169

Post by [deleted] »

ngoldbaum wrote: post #145
whatshisface wrote: post #37

Earlier quoted context omitted.

148nm is on the lower end of UV-C. It's higher-energy than the furthest ultraviolet light that the sun produces (200nm). If it were produced artificially, it'd be heavily absorbed by the atmosphere to the point of near opacity. If the visible spectrum was an octave, where the "tone" of a color wrapped around from red back to blue the way G wraps to A, it'd be the blue one octave above visible blue.

Teeny nit, the sun produces light well into the x-rays (mostly from the corona though). You're probably talking about sunlight making it through the atmosphere.

[deleted]

Re: Atomic nucleus excited with laser: A breakthrough after decades

#170

Post by [deleted] »

ngoldbaum wrote: post #145
whatshisface wrote: post #37

Earlier quoted context omitted.

148nm is on the lower end of UV-C. It's higher-energy than the furthest ultraviolet light that the sun produces (200nm). If it were produced artificially, it'd be heavily absorbed by the atmosphere to the point of near opacity. If the visible spectrum was an octave, where the "tone" of a color wrapped around from red back to blue the way G wraps to A, it'd be the blue one octave above visible blue.

Teeny nit, the sun produces light well into the x-rays (mostly from the corona though). You're probably talking about sunlight making it through the atmosphere.

[deleted]
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