38,314 reputation
353126
bio website inspirehep.net/…
location Duchy of Grand Fenwick
age 44
visits member for 4 years, 4 months
seen 16 mins ago

Experimental nuclear and particle physicist. These days I'm teaching, but I've spent a lot of time on nucleon structure in fixed target electron scattering and neutrino oscillations using reactors and beam sources.

Been reading Zemansky & Dittman's book on thermodynamics recently. Quote: ``The concept of temperature is rich in interpretations and levels of abstraction.'' Nice.


Mar
19
revised Is it correct to use $P=\large\frac{V^2}{R}$ for AC circuits?
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Mar
19
answered Is it correct to use $P=\large\frac{V^2}{R}$ for AC circuits?
Mar
19
comment How do I find the average kinetic energy and average potential energy of a hydrogen electron in the ground state?
You are on the right track. Why not just launch into the calculation building your operators from their classical analogues? Sometime flailing and failing a few times in the process of learning is helpful.
Mar
19
comment Ballast and water displacment principles
This is a calculation entirely analogous to finding the terminal velocity of a falling object.
Mar
19
comment How can one motivate the relativistic momentum?
Well, that's how I motivate Lagrangian mechanics: first the mirror rule and then refraction from the minimum time principle (using a lifeguard on a beach as a model for refraction), but I don't see launching into a long discussion to motivate the motivation.
Mar
19
comment How can one motivate the relativistic momentum?
This is neat. Alas, the student for whom I have to motivate this stuff have not seen Lagrangian or Hamiltonian mechanics yet.
Mar
19
comment Insight into Torricelli's Equation ($v^2=u^2+2as$)
The letters 's', 'u', 'v', 'a', 't' are the ones that appear in the usual constant-acceleration kinematics equation in certain formulation. Not a formulation that I like because they rely on assigning a rigidly selected set of symbols to certain physical quantities (one of my pet peeve is students thinking that there is a magical connection between certain letters and certain physical quantities); both it is a moderately popular formulation.
Mar
18
comment How can one motivate the relativistic momentum?
It occurs to me that your question might be simpler than that. Something along the lines of "How do I convince the students that we might need a new momentum rule?". In that case I go with "Change in velocity is the thing that controls change in momentum, but we already have a new velocity composition rules, so we may need a new rule for the evolution of momentum."
Mar
18
comment How can one motivate the relativistic momentum?
I've used arxiv.org/abs/physics/0402024 instead of the limiting glancing collision argument. I don't think it worked terribly well for the students I presented it to, but I like it. Mind you the authors claim to not used the work-energy theorem, but it's differential limit is used.
Mar
18
comment Contact between two rigid bodies. How does contact force is distributed in the contact surface?
It is worth noting that when you start to examine problems in this kind of detail the notion of rigidity ends up becoming a little, well, squishy.
Mar
18
comment Is Maxwell's field the wave function of the photon?
There is, of course, a relationship between the classical electromagnetic field and photons, but it is much more subtle than the field being the wave function of a photon which is nonsensical for several reasons starting with Ján's post below. I generally assume that people who write things like that are either lying to children (if I think they actually know better) or parroting something they heard (if I have no reason to believe they no better). I presume that Weinberg means exactly what he says.
Mar
18
comment Is Maxwell's field the wave function of the photon?
Or a 4-vecotr field of three spatial and one time coordinate, but that doesn't effect the argument at all.
Mar
18
comment Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
Related: physics.stackexchange.com/questions/138941/…
Mar
18
revised Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
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Mar
18
comment Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
To echo @SirElderberry The form-factors of bound nucleons differ from those of their free counterparts. There exist a host of different parameterizations of this for use in Monte Carlos. An early one that still see a lot of use is that by de Forrest.
Mar
18
revised Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
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Mar
18
revised Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
edited tags
Mar
18
answered Evidence that nuclei contain neutrons and protons (other than nucleons appearing if a nucleus is smashed)?
Mar
18
revised Do molecular bounded systems shield or reduce neutron cross-sections?
speling
Mar
18
comment Can the Sun capture dark matter gravitationally?
@DOS4004 You can pretty much assume that it does. The captured DM will have a variety of energies relative the sun meaning that their aphelion will vary. In fact, people have considered the terrestrial heat budget as a place to look for evidence of weakly interacting dark matter, but I believe that the total potassium-40 heating is still too poorly quantified to make the limit very interesting.