XPost: sci.electronics.design   
   From: bill.sloman@ieee.org   
      
   On 21/02/2026 9:19 pm, J. J. Lodder wrote:   
   > Bill Sloman  wrote:   
   >   
   >> On 21/02/2026 7:47 am, J. J. Lodder wrote:   
   >>> Bill Sloman  wrote:   
   >>>   
   >>>> On 20/02/2026 9:35 pm, J. J. Lodder wrote:   
   >>>>> Bill Sloman  wrote:   
   >>>>>   
   >>>>>> On 20/02/2026 7:41 am, J. J. Lodder wrote:   
   >>>>>>> wBill Sloman  wrote:   
   >>>>>>>   
   >>>>>>>> On 20/02/2026 12:13 am, J. J. Lodder wrote:   
   >>>>>>>>> Bill Sloman  wrote:   
   >>>>>>>>>   
   >>>>>>>>>> On 19/02/2026 9:56 pm, J. J. Lodder wrote:   
   >>>>>>>>>>> Bill Sloman  wrote:   
   >>>>>>>>>>>   
   >>>>>>>>>>>> On 19/02/2026 7:49 am, Ross Finlayson wrote:   
   >>>>>>>>>>>>> On 02/18/2026 12:43 PM, Python wrote:   
   >>>>>>>>>>>>>> Le 18/02/2026 à 20:13, Ross Finlayson a écrit :   
   >>>>>>>>>>>>>> ..   
   >>>>>>>>>>>>>>> and, you know, magnetic monopoles, is widely employed   
   >>>>>>>>>>>>>>> in medical imaging and the like.   
   >>>>>>>>>>>>>>   
   >>>>>>>>>>>>>> No.   
   >>>>>>>>>>>>>   
   >>>>>>>>>>>>> Resonance imaging (NMR) is a thoroughly different mechanism   
   >>>>>>>>>>>>> than Roentgen rays.   
   >>>>>>>>>>>>   
   >>>>>>>>>>>> But as the name implies, it's nuclei of the atoms involved that   
   >>>>>>>>>>>> exhibit the resonance. It's a remarkably low energy effect, and   
   you   
   >>>>>>>>>>>> need remarkably high magnetic fields to get it to give you a   
   >>>>>>>>>>>> detectable signal.   
   >>>>>>>>>>>   
   >>>>>>>>>>> Nevertheless, it is easily demonstrated in the kitchen   
   >>>>>>>>>>> with some simple electronics.   
   >>>>>>>>>>   
   >>>>>>>>>> Sort of.   
   >>>>>>>>>>   
   >>>>>>>>>> https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance   
   >>>>>>>>>>   
   >>>>>>>>>> There are lots of different ways to exploit nuclear magnetic   
   >>>>>>>>>> resonance. The earth's magnetic field is high enough to let you   
   >>>>>>>>>> devise experiments that can demonstrate the effect on a kitchen   
   >>>>>>>>>> table.   
   >>>>>>>>>   
   >>>>>>>>> Nothing 'sort of'.   
   >>>>>>>>> You -can- easily demonstrate the effect on the kitchen table.   
   >>>>>>>>> (at audio frequencies)  Wikipedia is right here.   
   >>>>>>>>   
   >>>>>>>> Yes, but we were talking about medical imaging, not nuclear   
   >>>>>>>> magnetic resonance in general, and your assertion is the   
   >>>>>>>> irrelevance here, as the text you snipped pointed out.   
   >>>>>>>   
   >>>>>>> Which 'we' dear Bill?   
   >>>>>>   
   >>>>>> If you can't work that out, you aren't worth talking to.   
   >>>>>   
   >>>>> Understood, your majesty.   
   >>>>>   
   >>>>>>> I replied to your   
   >>>>>>> ===   
   >>>>>>>>>>> But as the name implies, it's nuclei of the atoms involved that   
   >>>>>>>>>>> exhibit the resonance. It's a remarkably low energy effect, and   
   >>>>>>>>>>> you need remarkably high magnetic fields to get it to give you a   
   >>>>>>>>>>> detectable signal.   
   >>>>>>> ===   
   >>>>>>> which is just plain wrong.   
   >>>>>>   
   >>>>>> In your ever-so-authoritative opinion.   
   >>>>>   
   >>>>> FYI,   
   >>>>> Behaving like a stubborn ass doesn't improve your credibity in general.   
   >>>>   
   >>>> Calling people stubborn asses doesn't help yours either.   
   >>>   
   >>> Then don't behave like one.   
   >>> You've been long enough in SPR by now for an idea of who is who.   
   >>>   
   >>>>>>> As a matter of fact, zero to ultra-low frequency NMR   
   >>>>>>> is a flourishing research field these days,   
   >>>>>>   
   >>>>>> It's cheap to do, so lots of graduate students get stuck with studying   
   >>>>>> it. The results of their research don't seem to get published in   
   >>>>>> high-impact journals.   
   >>>>>   
   >>>>> Why can't you just admit that your statement that 'remarkably high   
   >>>>> fields are needed to give you a detectable signal'   
   >>>>> is just plain wrong?   
   >>>>   
   >>>> It does depend on what your are trying to detect. It's certainly true in   
   >>>> a lot of situations of practical interest. Laboratory NMR machines did   
   >>>> go in for high magnetic fields.   
   >>>   
   >>> Felix Bloch discovered it in the MHz regime, iirc.   
   >>> (he measured relaxation times)   
   >>>   
   >>>>> As a matter of fact NMR can be done in zero or near-zero fields,   
   >>>>> at very low frequencies.   
   >>>>> FYI, there is a large Wikipedia article devoted to it.   
   >>>>>    
   >>>>   
   >>>> That does depend on " highly sensitive magnetic sensors - SQUIDs,   
   >>>> magnetoresistive sensors, and SERF atomic magnetometers".   
   >>>   
   >>> Yes. Progress often comes from having more advanced instrumentation.   
   >>   
   >> Developing more advanced instrumentation can let you tackle previously   
   >> intractable problems. People talk about a solution looking for a problem.   
   >   
   > More kindly inclined people may call it 'pure science'.   
   >   
   >>>> Super-conducting quantum interference devices used to need liquid   
   >>>> helium.   
   >>>   
   >>> Yes, so what. You have that available, if needed, in a research lab.   
   >>   
   >> If you've got enough money. If you need helium-3 as your refrigerant,   
   >> you apparently need political influence as well.   
   >   
   > Scientists will be opportunists. They will do what can be done.   
   >   
   >>>> Presumably high temperature super conductors could let you get   
   >>>> away with liquid nitrogen, which is lot cheaper.   
   >>>   
   >>> Yes. but for research the cost of liquid Helium is not really important.   
   >>   
   >> But only if you have enough money.   
   >   
   > See above.   
   >   
   >>>> I was a chemist for long enough to be aware of the difference between   
   >>>> faddish research technique that you only found in research labs and more   
   >>>>     practical approaches that you run into in industry.   
   >>>   
   >>> There is no need to go overly defensive,   
   >>> the problem was you being too aggressive.   
   >>   
   >> I don't see it as a problem.   
   >   
   > We seem to have acquired an adequate feel for each other,   
   > in the meantime. No need for further problems.   
   >   
   >>> As for new research technique:   
   >>> it has to be tried before you can know what can be done with it.   
   >>> Meanwhile the results are publishable.   
   >>   
   >> It helps if they are publishable in a high impact journal.   
   >> When I was a graduate student one of the lecturers kept his students   
   >> busy publishing papers on the properties of the simpler conpounds of   
   >> technicium - the lightest element that hasn't got a stable isotope. He   
   >> had contacts in the reactor business that let him get hold of enough of   
   >> it to do that kid of work. The results got published in mior league   
   >> journals.   
   >   
   > Minor league professors tend to have minor league students,   
   > who may become in their turn minor league professors.   
   > So it goes, in this, the best of all possible worlds.   
   >   
   > Conversely, great names tend to have connections with other great names.   
   > Books have been written about it,   
   > like on 'heritability' of Nobel prizes.   
      
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