.comment-link {margin-left:.6em;}

2Physics Quote:
"Perfect transparency has never been realized in natural transparent solid materials such as glass because of the impedance mismatch with free space or air. As a consequence, there generally exist unwanted reflected waves at the surface of a glass slab. It is well known that non-reflection only occurs at a particular incident angle for a specific polarization, which is known as the Brewster angle effect. Our question is: is it possible to extend the Brewster angle from a particular angle to a wide range of or all angles, so that there is no reflection for any incident angle."
-- Jie Luo, Yuting Yang, Zhongqi Yao, Weixin Lu, Bo Hou, Zhi Hong Hang, Che Ting Chan, Yun Lai

(Read Full Article: "Ultratransparent Media: Towards the Ultimate Transparency"

Monday, March 12, 2007

Interferometric Detection of Gravitational Waves:
5 Needed Breakthroughs -- Seiji Kawamura

Seiji[ In our ongoing feature '5-Breakthroughs', so far most of our guests were from the exciting field of research on detection of gravitational waves. It started with David Shoemaker of LIGO and we also had Jean-Yves Vinet from French-Italian Virgo project and David Blair of the Australian effort, AIGO. Our today's guest is Prof. Seiji Kawamura of the Japanese endeavor, TAMA.

Seiji Kawamura is an associate professor at National Astronomical Observatory(NAO) at Mitaka, Tokyo, Japan. He was involved in joint Caltech-MIT LIGO project from its early days and worked on the 40m prototype interferometer (at Caltech), suspension system, and advanced R&D for the LIGO project between 1989 and 1997.

In 1997 he joined the TAMA project, the Japanese 300 meter interferometer for the detection of gravitational waves. As the leader of the detector group, he could lead TAMA to attain the world-best sensitivity at that time.

In addition he initiated and has been in charge of the resonant sideband extraction experiment, quantum non-demolition experiment, super-high frequency gravitational wave detection, and displacement-noise-free interferometer. He also leads the Japanese space gravitational wave antenna DECIGO.

Here is Seiji's list of 5 breakthroughs he would like to see in the ongoing worldwide effort to detect gravitational waves using interferometric antennas.
-- 2Physics.com Team]

"- homodyne detection with ponderomotive squeezing to suppress radiation pressure noise

- high-power laser to suppress shot noise

- cryogenic mirror/suspension to suppress thermal noise

- interferometer in space to remove seismic noise and to enhance gravitational wave signals

- displacement-noise-free interferometer to cancel all kinds of displacement noise"

Labels: , ,


Post a Comment

Links to this post:

Create a Link