Gerald
03-03-11, 09:06 AM
A laser can act as a "tractor beam", drawing small objects back toward the laser's source, scientists have said.
It is known that light can provide a "push", for example in solar sails that propel spacecraft on a "wind of light".
Now, in a paper on the Arxiv server, researchers from Hong Kong and China have calculated the conditions required to create a laser-based "pull".
Rather than a science fiction-style weapon, however, the approach would only work over small distances.
http://www.bbc.co.uk/news/science-environment-12620560
Note: 3 March 2011 Last updated at 00:27 GMT
It is known that light can provide a "push", for example in solar sails that propel spacecraft on a "wind of light".
Now, in a paper on the Arxiv server, researchers from Hong Kong and China have calculated the conditions required to create a laser-based "pull".
Rather than a science fiction-style weapon, however, the approach would only work over small distances.
http://www.bbc.co.uk/news/science-environment-12620560
Note: 3 March 2011 Last updated at 00:27 GMT