38,816 reputation
354126
bio website inspirehep.net/…
location Duchy of Grand Fenwick
age 44
visits member for 4 years, 5 months
seen 7 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.


34m
comment Q: Any standard terminology for “gold standard” Monte Carlo solutions
I'm not sufficiently conversant with the rules on Computational Science to be sure, but this might find a better home over there. If you are interested in having the question migrated, let me know and I'll ask the mods...
18h
comment Can we predict the half-lives of radioactive isotopes from theory?
Weak universality has been mentioned around here from time to time. It is the claim that the weak coupling to leptons is always the same ($G_F$) and that there is a well defined relation ship between the lepton coupling and that to quarks.
18h
answered Can we predict the half-lives of radioactive isotopes from theory?
22h
comment How is the uniform gravitational field approximation $F_g\approx mg$ near Earth's surface derived from Newton's law $F_g=GMm/r^2$ of gravitation?
See also: physics.stackexchange.com/questions/35878/…
1d
comment What is potential energy truly?
It might be helpful to eludicate that potential energy comes from the relative position of several components of a system. The boulder gets its bear annihilation capacity from its position relative the planet; take the planet away (and leave the bear an boulder floating is space) and the bear is safe again.
1d
comment Simple question relating to physics prac reports
You have not been specific about what the measurements you are making are, but your reasoning would be appropriate for a lab I ask my students to do. I asked about the number of measurement because if you had a statistical set and their distribution was only 2% wide it would suggest that your error estimate was simply high for some reason, or at least that some parts of it were highly correlated. However, given the size of your data set it would not be safe to draw any such conclusion.
1d
comment Simple question relating to physics prac reports
When you say "I have values for the elasticities that are all within 2% of eachother" how many measurements are you talking about?
1d
revised Why can't a high intensity beam be injected into the LHC when the machine is empty
various fixes for problems identified by DarioP
2d
comment Balancing an equation
I'm voting to close this question as off-topic because it is a chemistry question not a physics one.
2d
comment Balancing an equation
BTW in Physics "Maxwell's equations" invariably refers to the relationships between electric and magnetic fields. For the nonce I'm simple going to close this as off-topic. If someone can point me (or another mod) at the chemistry homework policy we might be able to migrate it.
2d
comment Equation derivation for skipping rocks
I believe I have a paper on this very subject, but it is at the office. Perhaps I'll get around to digging it out tomorrow and provide a reference.
2d
comment CP violation and arrow of time
Note that T-violation has been explicitly observed in some B-meson decays at the LHC. Don't have a paper pointer right now, but this happened during the first run.
Apr
16
comment Is the $\nu_e$ massive?
@Kyle My impression is that most people assume that it is, but we can't show that from data until we know the absolute masses or can show that the sum is large enough.
Apr
16
comment Is the $\nu_e$ massive?
Also by convention the mass state 1 is the one with the largest electron flavor admixture.
Apr
16
comment Neutrinos born before inflation
Look up the "cosmic neutrino background". They decoupled early and are at very low energy. Models for how they might be detected float around from time to time and I suspect that the most recent round of direct dark matter experiment may bring the technology along far enough to make some progress on that.
Apr
16
comment is electromagnetic phenomena and particle behavior dependent on dark matter?
It is not at all clear that dark matter "permeates". High mass models end up with pretty low particle densities.
Apr
16
comment Why do particles of equal mass (with one at rest) undergoing elastic collisions scatter at only right angles?
Because they scatter back-to-back in the CoM system.
Apr
16
comment Do subatomic particles have dimensions?
Note that nucleons are "subatomic" particles and they certainly are not point particles. The word you want is "fundamental". And the classical electron radius has no meaning whatsoever that can be related to the "size" of the particle which is subject to strong experimental upper bounds on order of $10^{-18}\,\mathrm{m}$.
Apr
16
comment Do subatomic particles have dimensions?
"We know atoms are mostly "made" out of empty space" ::grumble:: That statement may be suitable for pop-sci contexts but it is more wrong than right.
Apr
16
comment Carbon-14 formation in atmosphere
If you insisted on writing this as a two step process, which may or may not be reasonable, the correct intermediate state would not be $^{15}\mathrm{N}$ (which would imply the system was settled), but $^{15}\mathrm{N}^*$ to make it explicit that the intermediate state is excited.