Showtime: curious stroboscopic effect

*Okay, I guess that stuff's pretty interesting but... wait a minute, what?

PRESS RELEASE

Source: Franco Nori, RIKEN, Japan.

For immediate release: 21 May 2012

Hall effect at the speed of light: How can you demonstrate relativistic effects with your mobile phone?

(Saitama, Japan, 21 May 2012). The relativistic Hall effect describing objects rotating at speeds comparable with the speed of light has now been reported.

The work by Konstantin Bliokh and Franco Nori at RIKEN in Japan, NAS in Ukraine, and the University of Michigan in the US sheds light on aspects of fundamental physics, and you can demonstrate some aspects of this with your mobile phone.

As any cameraman knows, recording a fast rotating object such as a fan using a “rolling shutter” camera, like those found on mobile phones, results in weird distortions. See for example, http://www.youtube.com/watch?v=17PSgsRlO9Q, http://www.youtube.com/watch?v=LVwmtwZLG88&feature=fvwrel.

Less widely understood — until now — is the link between these distortions and some of the landmark theories in physics, namely Einstein’s relativity and the Hall effect.

Hall effects describe the interplay of rotation and linear motion in objects. There are already a number of manifestations of the Hall effect, including classical, quantum, and ‘spin-based’.

Relativity describes effects that arise when an object approaches the speed of light. This study considered the Hall effect as arising naturally under special relativity conditions without any external fields. The researchers found that a relativistic treatment of rotating bodies and quantum wave systems with angular momentum results in deformations and a shift in the geometric centre. The distortions have parallels with those found when recording a rotating object with a rolling shutter camera.

“Our description makes relativistic and quantum aspects of angular momentum fully consistent with each other,” conclude Bliokh and Nori. (((That's great, guys. Where's the demo? I'd love to see something crawling over a surface at the speed of light.)))

This relativistic approach may find applications over a wide range of length scales including elementary spinning particles, classical light and, even rotating black holes. (((Truck out the rotating black hole. Have at it. Can't wait. Try not to break anything.)))

http://phys.org/news205407631.html

(((And no fair with some pesky "relativistic Hall effect" that's the size of an electron! After those videos, I want to see it at least the size of a housecat.)))

Reference

Konstantin Y. Bliokh and Franco Nori, Relativistic Hall Effect: Phys. Rev. Lett. 108, 120403 (2012).

DOI: 10.1103/PhysRevLett.108.120403