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comment What is the Copenhagen interpretation of quantum field theory?
@Conifold, last sentence: I'm not quite sure what you're saying. I'd say QFT introduces states and operators as a mathematical model for statistics and correlations between events. As something of a riff on what I think you might mean, I find Lakatos's idea of "bridge principles", pragmatic connections between absolutely raw experimental data and theoretical models, is good enough for my relatively modest philosophical purposes. In such terms, "significance" and/or meaning of mathematical elements of a theory are not absolutely clear, but we just describe the connection as well as we can.
Nov
19
comment What is the Copenhagen interpretation of quantum field theory?
A classical PoV is just a different PoV; if we think in classical stochastic field terms as well as in the usual QFT terms we may notice things that we otherwise would not, but of course it might be a waste of time. We each just choose whatever approaches we individually think look hopeful. No reason to "expect" a classical underlying dynamics, but anyway we can pursue alternatives. The idea that the dynamics is Lorentzian is an empirical principle, so it might not be correct at all scales, indeed GR has it as not correct at large scales.
Nov
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answered Proof for quantized angular momentum
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answered What is the Copenhagen interpretation of quantum field theory?
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comment What is the temperature of an LHC Bunch?
@DarioP thanks. So I find somewhere that the energy spread is about $\mbox{1e-4}*\mbox{7TeV}=\mbox{700MeV}=m_p\gamma (\Delta v)^2$, where $\gamma\approx \frac{\mbox{7TeV}}{\mbox{1GeV}}=7000$, so $m_p(\Delta v)^2\approx 0.1MeV$ and $T\approx \mbox{(1e5eV)}*\mbox{(1.6e-19joule/eV)}/\mbox{(1.38e-23joule/K)}$ $\approx \mbox{1e9K}$. Within a couple of orders of magnitude of the transverse temperature, slightly smaller than the transverse temperature at the IP where there's greater transverse pressure but slightly larger elsewhere.
Feb
16
comment What is the temperature of an LHC Bunch?
I have from the Moehl lecture, $k_BT\approx m_p(\beta\gamma c)^2\epsilon/\beta_x\approx m_pc^2\beta\gamma\epsilon_n/\beta_x$, where $m_pc^2\beta\gamma$ is very nearly the beam energy per proton, so $T\approx\mbox{(7e12eV)}*\mbox{(1.6e-19joule/eV)}*\mbox{(2.5e-6m)}/\mbox{(0.44m)‌​}/\mbox{(1.38e-23joule/K)}$ $=\mbox{4.6e11K}$, taking numbers from rdemaria.web.cern.ch/rdemaria/www/hllhc11. I wasn't expecting something quite that high!?
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asked What is the temperature of an LHC Bunch?
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comment Renormalization in non-relativistic quantum mechanics
Similarly useful: Regularization, renormalization, and dimensional analysis: Dimensional regularization meets freshman E&M Fredrick Olness and Randall Scalise Citation: American Journal of Physics 79, 306 (2011); doi: 10.1119/1.3535586 View online: dx.doi.org/10.1119/1.3535586
Nov
29
revised Does the lagrangian contain all the information about the representations of the fields in QFT?
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