Actually, I tend agree with Robin that measuring cannot increase the energy of the particle. My question reflects my own attempt to understand why it is so. Now that I have thought about it, it is because one doesn't measure energy per se. Most measurements are really the result of calculations based on measurements of length and time plugged into a formula. BTW, the same is true of measurements of momentum. The modern physicists habit of refering to energy and momentum as "observables" is a perscription for phenomenological confusion. The resulting measures of length and time are only consistent with the supposed law-like properties of energy and momemtum on a statiscal level.
Harry On Fri, Aug 17, 2012 at 11:31 PM, <[email protected]> wrote: > Hello Harry, > > You asked -- > "So, the measuring instrument itself will produce energy, if it is used > to precisely measure the energy of a particle?" > > Probably not. > But maybe there are subtleties that obey the 2nd Law of Thermodynamics, > but allow for some counterintuitive effects. For example, refer to -- > > "Concentrating Energy by Measurement" > http://arxiv.org/abs/1012.5868 > > -- LP > > Harry Veeder wrote: >> On Fri, Aug 17, 2012 at 8:57 PM, <[email protected]> wrote: >>> In reply to [email protected]'s message of Fri, 17 Aug 2012 >>> 13:11:31 >>> -0400 (EDT): >>> Hi, >>> [snip] >>>>Pardon for this very late postscript, time is hard to find. >>>> >>>>I believe you assume a wave function totally confined in all >>>> 3-dimensions. >>>> This is probably not what was intended. It is easy to find papers >>>>describing crystal/lattice channel conduction of much higher energy >>>>particles (electrons, protons, ...). These are extended states - only >>>>confined in one or two dimensions. High energy particles do not >>>>necessarily break the lattice structure. >>>> >>>>-- LP >>> >>> What I meant to do was calculate the momentum (assuming a kinetic energy >>> of >>> 0.782 MeV for the proton), and divide it into h-bar/2. However it >>> appears I got >>> something slightly wrong the first time around. The value I get now is >>> 2.57 fm >>> for a proton, and 0.93 fm for the deuteron. >>> >>> However I don't really stand behind the entire concept. I don't think >>> the energy >>> of particles magically increases when they are confined. I do think the >>> measurement uncertainty increases, but that's not the same thing as >>> their actual >>> energy. Instead, I see it as a limitation on our ability to measure, not >>> a >>> change in the actual properties of the particle itself. >>> IOW the restriction applies to us, not to the particles. >>> Regards, >>> >>> Robin van Spaandonk >>> >>> http://rvanspaa.freehostia.com/project.html >>> >> >> So, the measuring instrument itself will produce energy, if it is used >> to precisely measure the energy of a particle? >> >> >> Harry >> >> >> > >
