Chien-Shiung Wu was a Chinese-American physicist who specialized in experimental physics and radioactivity, at a time when few women were in the field. She worked on the Manhattan Project, where she helped to develop the process for separating uranium metal into the U-235 and U-238 isotopes by gaseous diffusion. She later performed experiments that helped further our understanding of physics.
She was also the first:
- Chinese-American to be elected into the U.S. National Academy of Sciences
- Female instructor in the Physics Department of Princeton University
- Woman with an honorary doctorate from Princeton University
- Female President of the American Physical Society, elected in 1975
- Person selected to receive the Wolf Prize in Physics in its inaugural year of 1978.
Her honorary nicknames include the “First Lady of Physics,” the “Chinese Marie Curie,” and “Madame Wu.”
Abdus Salam was a Pakistani theoretical physicist and Nobel laureate in Physics known for his work on the electroweak unification of the electromagnetic and weak forces, for which he (along with Sheldon Glashow and Steven Weinberg) won the Nobel Prize in 1979, becoming the first Pakistani and the first Muslim scientist to receive a Nobel prize in Physics (as well as the first Ahmadiyya). His work was instrumental to laying the groundwork for the discovery of the Higgs-Boson. It’s a shame that his contributions are barely acknowledged today.
If Earth is a blue marble, it’s certainly not one you’d want to depend on in the chalk circle. Instead of being a sphere, it’s actually far more irregular (and not just the mountains, duh). Charles Q. Choi lays out lots of oddities about our lumpy planet at SciAm.
Here’s some tidbits:
- Earth is actually an oblate spheroid, bigger at the equator than at the poles.
- Gravity is unevenly distributed around Earth, which looks something like this when you draw it.
- Areas of the crust and mantle are still rising up to a centimeter a year after being crushed beneath the weight of glaciers during the ice age.
I hope that the Earth doesn’t feel self-conscious, though. Because we all have our imperfections. And this lumpy ball of dirt and magma is the only home we have.
Cops beware: scientists will make your jobs a lot harder.
In his paper "The Proof of Innocence" Dmitri Krioukov, a physicist at the University of California in San Diego, outlined for a judge the mathematical reasons why he was not guilty of running a stop sign. It may seem like a lot of effort for one ticket, but Krioukov is no longer on the hook for the $400 he owed.
In making his case, Krioukov wrote that a police officer can perceive a car as not having stopped — even though it really did stop — if three different criteria are met:
"(1) the observer measures not the linear but angular speed of the car; (2) the car decelerates and subsequently accelerates relatively fast; and (3) there is a short-time obstruction of the observer’s view of the car by an external object, e.g., another car, at the moment when both cars are near the stop sign."
For those who’d like a simpler explanation, the blog Physics Central broke down Krioukov’s argument in layman’s terms with an illuminating analogy about trains:
“When Krioukov drove toward the stop sign the police officer was approximating Krioukov’s angular velocity instead of his linear velocity. This happens when we try to estimate the speed of a passing object, and the effect is more pronounced for faster objects.
Trains, for instance, appear to be moving very slowly when they are far away, but they speed past when closer. Despite these two different observations at different distances, the train maintains a roughly constant velocity throughout its trip.”
In addition to including colorful diagrams, Krioukov was thorough with his details of the events that transpired: he wrote of having a cold on the day of the supposed violation and expounded on the impact a single sneeze had.
This is definitely the most creative and sophisticated way I’ve ever heard anyone beat a ticket. I wonder how many others will try to emulate his argument.