Recent content by Will Learn

Thanks. Sorry it's taken me a while to reply. I'm not going to be following this thread as much and may not reply to people quickly from now onwards.

Hi. Thanks. I have now read that Wiki article. I had just recently found some information about the classical Compton radius for an electron and some of the older work done by Thomson on the subject. Ultimately, most sources of information I've seen so far seem to end their...

Hi and thanks for everyone's time. The least I can do is try to reply to all of the above comments. That's a nice clear answer. I would very much like it to be this way - but the consequences are significant and I hope you'll understand that I have to slow down and consider it...

Hi. Thanks for your time and advice @anorlunda . I've only scanned through those pages at the moment. It seems very general but this section seems most relevant: Einsteins 1905 derivation: ... This was tackled by Einstein in his paper "Does the inertia of a body depend upon its...

Hi. Yes. I'm sure that's true, if a shame. I'd still be interested in the theory, even if the experiment isn't available yet. Best Wishes.

Hi again, Would it help if we restrict attention to a solenoid or capacitor? A capacitor is the obvious choice since that uses an E Field. For an ideal capacitor, the E filed is confined to the region of space between the plates. At least here, the E field doesn't extend all over the...

Hi. I'm not sure where to put this question, it concerns particles, mass-energy equivalence and various things. Classical electromagnetism seems to be as sensible a place as any. There is energy stored in an E field. Energy density (at position r, time t) = \frac{1}{2}...

Hi again. I don't consider myself an expert on Inflation. My advice is limited. I also don't check the forum often, so don't wait for me to reply. It could be weeks. I've spent a bit more time and read the pages in the book again. Actually, there is a risk that the conditions...

Hi. You're not getting a lot of responses, so I hope this will be of some help. Have you got access to a library? My main source of information is "The History of the Universe", David H Lyth, publisher: Springer, 2016 It's a short book which (in my opinion) is suitable for...

Hi. You're doing well and taking an interest in Physics, we're all going to like that. You've stumbled on some Pop Sci articles and you are, quite correctly, identifying problems with what they've implied in their simplification. That's the bit I would suggest you focus on if you want...

Thank you to everyone. I'll leave you all in peace now.

Yes I have looked at both wikipedia articles suggested by Peter Donis and Dale. I'm not trying to waste your time and just ignoring the links you provide. This formula (screenshot 1) taken from Wikipedia (https://en.wikipedia.org/wiki/Electromagnetic_stress%E2%80%93energy_tensor) - - - - -...

I don't - but those formulae don't describe the stress-energy tensor for a permanent bar magnet. They describe the tensor for a source-free electromagnetic field. I want to include the bar of Iron itself, this has mass.

Thanks Peter Donis. I'm seeing a problem here: I need the stress-energy tensor to derive the inertial mass BUT I can't derive the stress-energy tensor without knowing what the mass is. Nevermind, perhaps there isn't a clear answer. Thanks for your time.

Thanks everyone. I think the replies have overlapped a bit here. I did say the above but I was referring to something Scott said not something Peter Donis said. It's my fault for not making that clear. At the time I started my post Scott was the ONLY reply and it never occurred to me...