42,635 reputation
458136
bio website inspirehep.net/…
location Duchy of Grand Fenwick
age 44
visits member for 4 years, 9 months
seen 1 hour 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.


Aug
21
comment A follow up on “Double Slit Experiment in a Bubble Chamber”
Notice that I discuss liquid noble gas TPC's in my answer to the original. That's the up to data technological equivalent. Also, bubble chambers have made a partial comeback for use in direct dark-matter detection in the last few years.
Aug
20
comment What the lifetime of a massless black hole of photons?
While photons are individually massless, a collection of photons taken as a system generally have a mass (the only exception comes when they all have parallel momentum), and if they form a black hole they certainly have a mass.
Aug
19
comment Help with relativity simultaneity paradox
This is usually described in terms of a barn and a pole. Also the rivet-and-hole variant: physics.stackexchange.com/questions/180998/…
Aug
19
comment Am I attracting Pluto?
@SchighSchagh "Since the center of mass of the Earth-Antonio system is preserved, so too is the pull of the Earth-Antonio system on Pluto" Is only strictly true with spherical symmetry. In reality, there is a tiny dipole created which has a non-zero effect (albeit vanishing even compared to a very modest effect that Earth has on Pluto in the first place).
Aug
19
comment How does one integrate an equation with a tensor?
Your problem statement tell you that: $\mathrm{d}S$ is the normal to the surface at the point of consideration. If the geometry is simple this really is almost as easy as the kinematics problem. For more complicated geometries you probably want one of the theorems from vector calculus to help simplify the problem.
Aug
19
comment How does one integrate an equation with a tensor?
You probably do know what to do with it and just don't recognize the fact. Here's a problem that you know involving integrals and vectors: given a particle with initial position $\vec{x}_0$, initial velocity $\vec{v}_0$ and constant acceleration $\vec{a}$, find the position as a function of time. The extension to higher rank tensors is similar.
Aug
19
comment Is there any difference in mixing and oscillation of neutral mesons?
I don't recall hearing the term applied to meson systems (as opposed to neutrino systems), and I would guess this is related to the short lifetimes of the strongly interacting states that exhibit mixing.
Aug
19
comment Am I attracting Pluto?
@SarveshMishra See physics.stackexchange.com/search?q=speed+of+gravity+is%3Aq and particularly physics.stackexchange.com/questions/201191/…?
Aug
19
awarded  Great Answer
Aug
19
comment Why isn't spent nuclear fuel used as a heat source?
@ChrisWhite Well, the night shift at Chernobyl managed to produce an explosive steam escape event. And the story of how they managed it would be a comedy of errors if not for the outcome.
Aug
18
comment Am I attracting Pluto?
Nice. A Fermi answer to a pop-sci sort of question.
Aug
18
comment Electron Flow Notion
The direction of force on the charge carriers is the same, making the sign of the Hall voltage diagnostic.
Aug
18
comment Two sets of coordinates each in frames $O$ and $ O' $ (Lorentz transformation)
Yes. In general matrix multiplications don't commute. You need to construct similarity transformations.
Aug
17
comment Does running water out of a faucet prevent the pipes from bursting? If so, why?
physics.stackexchange.com/questions/2431/…
Aug
17
answered 4 momentum in particle physics, collision of positron and electron
Aug
17
comment Two sets of coordinates each in frames $O$ and $ O' $ (Lorentz transformation)
Does matrix multiplication commute? Does that give you a hint?
Aug
17
comment Am I attracting Pluto?
@MarcvanLeeuwen People have played around with retarded Newtoninan theories, and they have some interesting properties (like still generating elliptical orbits). In the full relativistic theory, of course, the field at play is space-time. And certainly the language is strained by attempting to express these relationships. J-S' comment about the locus of attraction, is bang on, of course.
Aug
17
comment What would happen in this “close to the speed of light” scenario?
Not "just probably isn't possible": absolutely isn't possible as it requires that the atoms at the far end learn about what happened at the near end faster than light speed allows. When you start considering things that would ideally violate relativity ductility becomes compulsory.
Aug
17
comment What would happen in this “close to the speed of light” scenario?
Choosing the wrong tag may have contributed to that not coming up in the similar questions you get when you start a new question.
Aug
17
revised What would happen in this “close to the speed of light” scenario?
edited tags