21 February 2011 Twisted Light to Reveal Spinning Black Holes

Artistic view of twisted radiation close to a rotating black hole (credit: F. Tamburini).

A team including researchers at ICFO proposes in Nature Physics a technique to reveal exotic objects in space. Researchers at the University of Padua, the Swedish Institute of Space Physics, Macquarie University and ICFO propose in a paper recently published in Nature Physics a technique that could enable the detection of spinning black holes. The paper is titled ‘Twisting of light around rotating black holes’

The technique is based on a relativistic effect mostly unnoticed by astronomers and space physicists until now: electromagnetic radiation emitted by sources very near the black-hole event horizon is imprinted with orbital angular momentum. As a result, the phase of the radiation has a distinctive spatial distribution, a unique observable \"fingerprint\". This result opens the way to new observational tests of General Relativity.

The team includes researchers with different background and expertise (from astrophysics to photonics): Dr. Fabrizio Tamburini, University of Padua, Italy; Prof. Bo Thidé Swedish Institute of Space Physics; former ICFOnian Dr. Gabriel Molina-Terriza, Macquarie University, Australia; and ICFO postdoctoral researcher Dr. Gabriele Anzolin.