Category Archives: physics

Collaborative tools of the trade

I think you would agree that with recent introduction of cloud services collaboration has become easier.  Ftp/sftp/scp have become nearly obsolete. Here is a couple of tools that we find useful:

  1. Dropbox. This is a cloud file service. The first 2 Gb (which is a lot) are free. An essential tool for sharing projects between group members. Indispensible for  synchronizing files across various platforms, PCs, Macs, smartphones, ipads, etc. Five out of five stars.
  2. Mendeley. Bibliography manager. Free. Multiplatform. We share citations and papers (pdf's) between group members; anyone can add and modify references. Mendeley has a convenient option for exporting bibliography into latex .bib file (library.bib). At the moment flaky but still useful. Three out of five stars.

Setting working directory in mathematica

One of mathematica annoyances when working with external files (various import/export functions), is that it defaults to the user's Documents directory. I usually keep the data/graphics files  in the same directory as the mmka notebook and its painful to specify the full path every time.

Here is a command that sets the working directory to the notebook directory.

SetDirectory[
DirectoryName[
ToFileName["FileName" /. NotebookInformation[SelectedNotebook[]]]]]

UPDATE: Easier (thanks Pedro!):
SetDirectory@NotebookDirectory[]

 

Tweaking Mathematica output for order-of-magnitude estimates

Here is a trick I find useful when quickly estimating order-of magnitude values of various quantities  in Mathematica. The statements below force the format of all numerical output to be in the scientific notation (x 10^y).

oldPost = $Post;
format[x_Real] :=
NumberForm[x, ExponentFunction -> (If[-1 < # < 1, Null, #] &)];
format[x_] := x;
$Post = format;

When you execute these statements, the output formatting will persist for the rest of the mmka session. If you want to go back to the default output format in the session, execute

$Post = oldPost;

"I attribute essentially all my success to the very large amount of chocolate that I consume.  Personally I feel that milk chocolate makes you stupid.Now dark chocolate is the way to go. It's one thing if you want like a medicine or chemistry Nobel Prize, OK, but if you want a physics Nobel Prize it pretty much has got to be dark chocolate."

--- Erik Cornell

History of atomic physics at the University of Nevada, Reno

With the on-going search for an experimental atomic physics faculty at the University of Nevada, Reno (UNR), I would like to provide a historical perspective on strong traditions of atomic physics at UNR.

The early history of atomic physics at UNR is succinctly captured by Hulse, Goodall and Allen in their book  "Reinventing The System: Higher Education In Nevada, 1968-2000".

"The physics faculty began building a solid record in atomic and molecular physics in the 1960s and improved on this foundation into the 1990s; Philip Altick, trained at Stanford and Berkeley, was an academic leader in this field for three decades and is recognized for initiating the department's high research standards. Colleagues Peter Winkler and Reinhard Bruch were attracted to UNR from Germany partly because of the important theoretical work under way here. Ron Phaneuf, department chair through most of the 1990s, was credited with advances in the program during that decade."

While Ron served as Department Chair, he established a program to study photoionization of ions at the Advanced Light Source in Berkeley. During that same period the UNR AMO program also grew. Faculty hires included Rami Ali, a recognized expert in experimental atomic collisions. After spending several years at UNR, Rami  accepted an academic post in his native Jordan. Paul Neill collaborated on electron beam ion trap physics at Lawrence Livermore National Labotratory. Jeff Thompson has made important progress in measuring properties of negative ions and maintains that research program while serving as the Dean of College of Science at UNR.

Following Philip Altick’s retirement, a theorist, Andrei Derevianko, was hired. Andrei's interests are broad but primarily are in atomic clocks and in connecting atomic physics with particle and nuclear physics. Meanwhile, the entire field of AMO physics was being reshaped by advances in ultracold atom physics. Jonathan Weinstein was hired to expand in this important frontier. Jonathan uses cryogenically-cooled atoms and molecules to study cold collisions, cold chemistry, and quantum information. The most recent addition to the AMO program is Andrew Geraci. Andrew's experiments are in the rapidly growing fields of optomechanics, quantum precision sensors, and hybrid quantum systems.