40,826 reputation
356130
bio website inspirehep.net/…
location Duchy of Grand Fenwick
age 44
visits member for 4 years, 7 months
seen 2 hours 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.


Jun
26
comment Detectable interactions in Cherenkov detectors
It is not entirely clear to me that the OP will recognize that you are treating $\nu_\mu + n \to \mu^- + p$ as being "the same" as the electron flavored charged current interaction. Being more specific might help.
Jun
26
comment If you double the mass of a moving object - is its kinetic energy quadrupled?
"If you double the speed of an object, you quadruple its energy" Is correct, but "(which is why transport agencies do campaigns to reduce drivers speeding)." is mostly not. The thing that drives the desire for lower speed (aside from safety) is that the drag forces rise as $v^2$ or worse. The kinetic energy issue pushes the wonks to rail against "jack-rabbit starts", but for cross-country driving it resistive losses that dominate by a huge factor.
Jun
25
comment Ice bath is always 3C, why?
I wouldn't discount the digital too much. The one we bought with up-to-date calibration was within that range of zero. And there are more than a few classical analog devices which need to have their calibration checked regularly. It's just that sealed mercury-in-glass device doesn't drift as long as you can keep the column continuous (and have fun trying to fix it if the ^%@# column ever separates). The real lesson is devices that can exhibit drifts need to be up-to-date or they are not trustworthy to the claimed precision.
Jun
25
comment The relation between commutation and quanta
It might be worth noting that free particles still have non-computing conjugate operator pairs (say $\hat{x}$ and $\hat{p}$), but don't experience the quantization of energy levels that appears for bound particles. This is because the quantization fundamentally caused by the boundary condition to which the particle state is subject. Until you are clear on that I'm not sure there is any point in even asking the question.
Jun
25
revised How is mass conserved when a muon decays?
added 281 characters in body
Jun
25
answered How is mass conserved when a muon decays?
Jun
25
comment What experimental proof has been found of Einstein's theory?
You are trying to apply intuition that evolved with relative velocities of a few 10s of meters per second and these days is almost able to contend with a few hundred m/s difference to reason about things that happen up to six orders of magnitude faster than that. You shouldn't expect your intuition to work and the plain experimental fact is that it does not.
Jun
25
comment How to measure the diameter of a thin wire?
I'm just suggesting that the OP is exhibiting an inconsistent set of expectations in his responses to various suggestions. Getting 1% with stuff found in your desk is way cool.
Jun
25
comment How to measure the diameter of a thin wire?
Not that there is anything wrong with this technique, of course, but a 1% measurement isn't a patch on what could be accomplished with 50-100 wraps and a caliper.
Jun
25
comment Proof of vertical and horizontal velocity component in projectile motion
Note that those particular trig function arise from one choice of convention for measuring the angle. You are safer understanding that than memorizing the two formulas that you exhibit. Lest some stinker of a professor gives you a problem in which the angles are specified from the vertical or some such. Not that I would do that. Not me. No really.
Jun
24
answered Ice bath is always 3C, why?
Jun
24
comment Is crystal diffraction actually diffraction?
You are running into the usual trouble with finding a definition for "diffraction". It is a arguable position that there is no such definition. But the people who use that technique refer to it as diffraction, and you will also here people discuss "diffraction scattering" at time.
Jun
24
revised The stunning footage of neutral currents, first observation of a neutrino: Knowledge needed
added 22 characters in body
Jun
24
comment The stunning footage of neutral currents, first observation of a neutrino: Knowledge needed
Related: physics.stackexchange.com/q/60894
Jun
24
comment Can we have physical quantities which have magnitude and direction but are not vectors?
It's worth noting in this context that pseudovectors like angular momentum exhibit the right behavior under proper rotations but a different behavior from vectors under reflection and improper rotations.
Jun
24
comment How to measure the diameter of a thin wire?
At this point there is a serious disconnect between "I just want a number as the diameter of my wire", and your complaining measuring many turns won't give a good answers below. The wrapping approach is the classic method (and can give you an answer in "gauge" directly if you care for that sort of thing) and can be very accurate if combined with either a vernier caliper or a micrometer.
Jun
24
comment Weather Meridians
The stack exchange Earth Science site that HDE mentions is in beta and we have a general rule to be careful about migrating to beta site. If you would like to have your question migrated there just comment to that effect and a mod will get to it by and by.
Jun
23
comment X-ray characteristic radiation
Or somethimes they have to moonlight ... taking part-time jobs in several atoms that form a vertical trust^W^W benzene ring.
Jun
23
comment How are Dual-energy X-ray absorptiometry (DXA/DEXA) scans affected by surface stability?
As far as I'm concerned this is framed in a way consistent with an experimental error analysis question and is fine for the site, but ... I don't know that we have any regular users who are sufficiently familiar with that kind of kit to give you a good answer.
Jun
23
comment suitable hardware for Physics Simulations
Joe, migrations require the vote of serveral high-rep users (for a few sites) or a moderator action (for most). I don't think that Computational Science would like this question in this form, so I am reluctant to migrate it. Sorry.