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Apr
27
comment Experiment proving that the Earth is rotating around the Sun
To be really thorough you'd combine this with precision measurements of stellar spectra to show the annual variation in the position of spectral features as the Earth's velocity toward and away changes by a total of $60\,\mathrm{km/s}$. This does require a precision of $10^{-4}$ in frequency measurements.
Apr
27
comment Reversing Entropy
Please do not attempt to use Physics as an advertising platform.
Apr
27
comment Einstein's equation of Entropy in Brownian Motion paper
Like most papers, it was written by a physicist for other physicists. The author assumed you would be familiar with the important developments of the day.
Apr
27
comment Arrangement of Nucleons due to Strong Force
This is an attractive idea if you're taking the "little balls" picture seriously, but that is a huge mistake. There is nothing in nuclear physics that even remotely resembles what is described here: the system is purely quantum mechanical.
Apr
27
comment Are units of angle really dimensionless?
Well, Joules are scalar Newton-meters, and Torque units are pseudo-vector Newton-meters, so you can differentiate them by their tensor character.
Apr
27
comment Arrangement of Nucleons due to Strong Force
You shouldn't take the pictures of colored balls as indicative of anything. These systems don't behave like bonding atoms and don't have a well defined inter-object geometry because the objects don't have well defined positions.
Apr
27
awarded  experimental-physics
Apr
26
comment Does contracted spring weigh more than stretched one?
I'll repeat a comment I made on 159688: most of the mass of 'ordinary' stuff around you is binding energy. It's not that you have to try hard to work this out, it's that you've never weighed anything without this effect dominating.
Apr
26
comment How does time get on our clocks?
You're going about this all wrong. There is no mystery here: human looked for things that happened regularly, then built machines to count how many times those things happened. They called them "clocks".
Apr
26
comment The mass-energy equivalence is a principle which can not be derived from anything?
Several of the answers to the proposed duplicate do exactly what is requested here. I have to agree with John, this is a duplicate.
Apr
26
comment The derivation of the Mass-Energy(including mechanical energy) equivalence principle
Please do not delete and re-post a question that was closed.
Apr
26
comment How can an electron fake a jet?
Experimenters are pragmatists. We do our level best to figure out the processing scheme that will get the most out of the data and then we use that scheme. Sometimes you can work that out on the back of an envelope; sometime is takes a twenty-page white-paper; and sometime you just have to Monte Carlo it to a fare-thee-well.
Apr
26
awarded  Nice Answer
Apr
26
comment How can an electron fake a jet?
At this point I run into the fact that I've never done collider physics. I don't know enough to be certain why they would chose a particular approach. You could get coincident signals in the calorimeters several ways. Incident electron + DIS. Incident hadron and a single hard electron scattering event (should be rare but is certainly possible). Coincidental arrival from two sources. Weak decay of a flavored hadron at the right time. Probably others. Whatever scheme you chose has to fail well across all the options.
Apr
26
answered How can an electron fake a jet?
Apr
25
revised A reference request for real world experimental data
added 372 characters in body
Apr
24
comment How does Compton scattering demonstrate particle over wave behavior?
"some people consider it to be a waste of time apparently" It's not so much a waste of time, but that the time simply isn't available if students are to be shepherded through the usual preparation in the usual number of terms at conventional loads. I consider it an advantage of ahistorical ordering in a modern physics course that you can pick and chose which transition arguments to present. Those that won't be covered in adequate detail simply aren't covered at all. Of course that replaces a superficial historical awareness with a deeper but patchy one, so you could reasonably disagree.
Apr
24
revised Measuring very long half lives accurately
deleted 48 characters in body
Apr
24
comment Conventions for propagators in Feynman diagrams
Chat discussion: chat.stackexchange.com/transcript/message/29225208#29225208
Apr
24
comment Conventions for propagators in Feynman diagrams
To duplicate my wording on a chat discussion of this questions: There is no Ruling Junta of Physics Notations and Conventions and this stuff varies. And that's a general rule. Conventions develop, settle, get shaken up, mutate, re-settle, exist in two armed camps for decades at a time, and exhibit all kinds of behavior and divergences. It's simply not safe to think that there is One True Way to do things. And even when there is One True Way right now there is no guarantee that it will be respected by the 2o year old paper you have to dig up to understand a phase in a paper.