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Do you know when the energy content of electrons was actually measured as .511 MeV? was the first measurement true to current value? and, most of all, how was/is it measured with precision?
Wouldn't you say that knowing the Mass in kg would give a direct value to the eV equivalent value? (e=mc2)? If you read the history of the discovery of the electron, the measurement of its e/m and then the measurement of m you can decide for yourself where the point was that the "precision" was arrived at. (c was measured very accurately, way back - again, the history of that is interesting to read.)Do you know when the energy content of electrons was actually measured as .511 MeV? was the first measurement true to current value? and, most of all, how was/is it measured with precision?
Wouldn't you say that knowing the Mass )
Thanks, but that was a theoretical discovery and also,at the time you mention, the equivalence mass-energy had not been ascertained.I think it was measured by a combination of physicists 9
Thanks, but that was a theoretical discovery and also,at the time you mention, the equivalence mass-energy had not been ascertained.
What I clearly asked is when the theory was confirmed by a concrete experiment that revealed energy= .511 MeV, did it happen much later when pair annihilation was possible? and how is energy concretely measured?
I'm having a problem with the logic here. If "annihilation" was observed and appreciated for what it is, then wouldn't that imply an awareness of the mass/energy equivalence?What I clearly asked is when the theory was confirmed by a concrete experiment that revealed energy= .511 MeV, did it happen much later when pair annihilation was possible? and how is energy concretely measured?
Thanks, but that was a theoretical discovery and also,at the time you mention, the equivalence mass-energy had not been ascertained.
What I clearly asked is when the theory was confirmed by a concrete experiment that revealed energy= .511 MeV, did it happen much later when pair annihilation was possible? and how is energy concretely measured?
Thanks anyway
Is it really so hard to understand?I don't understand the issue here.
Then, using the knowledge of the electron charge, the value of the mass of an electron drops right onto your lap. The "energy equivalent" is simply a conversion from mass to energy via the infamous Einstein equation. There isn't any need to perform another experiment JUST to verify that the conversion is valid for an electron.Zz.
It is verified thousands of times a day in PET detectors across the world as a part of standard medical imaging. I just don’t know when it was first measured historically.if not, then you mean that the value and the infamous equation has not yet been verified.
I am quite uncomfortable with this comment. Please review the forum rules. Personal speculation is not tolerated. The energy mass equivalence is well established both theoretically and experimentally.an infamous equation that was soon disqualified by scientists that showed the circularity of the so-called derivation.
But, even conceding that the equation means something,
The fact that it was confirmed ,( it would be nice if you told us where to find more details), doesn't mean that Einstein proved it, it was a lucky guess based on experiments by Hasenhorl on heat and others on 'electromagnetic mass'. In itself it has no scientific value, even theoretically, and everybody knows that, which is not my personal speculation . If you think to the contrary, I challenge you to explain the logical/scientific structure of the derivation, if you canI
I am quite uncomfortable with this comment. Please review the forum rules. Personal speculation is not tolerated. The energy mass equivalence is well established both theoretically and experimentally.
I'm not sure what you are driving at here. You initially asked a question based on Scientific History but now you seem to be doubting the validity of a very well established concept. I think that it is really up to you to produce a good reason to justify your doubt; that's the way it works. If it happens that the 'right answer' came from a bit of a fudge at the start then that is not a rare thing to happen in the advance of Knowledge.The fact that it was confirmed ,( it would be nice if you told us where to find more details), doesn't mean that Einstein proved it, it was a lucky guess based on experiments by Hasenhorl on heat and others on 'electromagnetic mass'. In itself it has no scientific value, even theoretically, and everybody knows that, which is not my personal speculation . If you think to the contrary, I challenge you to explain the logical/scientific structure of the derivation, if you can
...measured through annihilation or other, and what was the method, equipment used.
The fact that it was confirmed ,( it would be nice if you told us where to find more details), doesn't mean that Einstein proved it, it was a lucky guess based on experiments by Hasenhorl on heat and others on 'electromagnetic mass'.
In itself it has no scientific value, even theoretically, and everybody knows that, which is not my personal speculation . If you think to the contrary, I challenge you to explain the logical/scientific structure of the derivation, if you can
Thanks for the support, Mister T.quite so. Nobody,except some members of this forum consider that paper as a proof, as anyone can check on the web. But I look forward to Dale's arguments!Einstein never claimed he had proven it. In fact, quite the opposite.
Thanks, that's is a rather appropriate and adequate answer to my queryMaybe, this presentation provides some hints:
Electron-positron Annihilation - SCIPP - UC Santa Cruz
Thanks for the support,
Certainly. Any textbook on PET imaging will do. Here is a brief online referenceit would be nice if you told us where to find more details
Looking at the OP’s past history of posting, that is an agenda that he/she was deliberately trying to promote.I do not seem to understand how this thread has derailed from a simple question as to how different properties of electrons were confirmed, to a full blown discussion of questioning the mass-energy principle.