Ryan Dahn

3 weeks ago | physicstoday.scitation.org | Ryan Dahn |Lindsay McKenzie |Peter Turchi |Peter W. Milonni

For insect-scale flapping-wing robots, landing is perhaps the most dangerous portion of flight. Close to the ground, the wings generate unpredictable air vortices that often cause hard or crash landings. The rigid, single-segment legs that researchers typically use on the robots struggle to reliably cope with the collision forces generated during landings, which can easily damage fragile components such as the wings or the piezoelectric or electromagnetic actuators that power the devices.

Apr 12, 2024 | pubs.aip.org | Ryan Dahn |Toni Feder |Alex Lopatka

The total solar eclipse of 29 May 1919 propelled Albert Einstein to international celebrity. During the precious moments when the Moon blotted out the solar disk, a team of astronomers, including Arthur Eddington, measured the deflection of starlight by the Sun’s gravitational field and found it to be consistent with the amount predicted by Einstein’s theory of general relativity (see the article by Daniel Kennefick, Physics Today, March 2009, page 37).

Jul 21, 2023 | pubs.aip.org | Ryan Dahn |Andrew Grant |Bo Miao |Holly Gilbert

“When all is interwoven with the dramatic events that centered around him, we remember Oppenheimer as one of the most remarkable personalities of this century. In the years to come the physicist will speak of him. So will the historian and the psychologist, the playwright and the poet.”Abraham Pais, a theoretical physicist and historian of science, expressed this sentiment in his 1967 Physics Today tribute to J. Robert Oppenheimer.