The scientists were able to observe the quasars using a technique called gravitational lensing.
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Another group of researchers wants to study galaxy clusters using a phenomenon called gravitational lensing.
Some experts in the field seriously question whether it is possible to develop materials capable of perfect lensing at optical frequencies.
The bending creates a lensing effect in the same way that light is bent through glass or plastic in a microscope or your eyeglasses.
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Her work uses cosmic gravitational lensing to measure dark energy in the universe in order to help understand how the Universe appears to be accelerating in its expansion.
They did so by employing a technique called gravitational lensing.
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"There have been 'gravitational lensing' detections before over small areas, but this is the first time we've been able to do this kind of thing over the whole sky, " he told BBC News.
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The camera should be able to gather enough data to allow all four possible avenues for exploring dark energy: galaxy clusters, supernovae, large-scale galaxy clumping and weak gravitational lensing, at the same time.
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On 17 March 2005, Andrzej Udalski, professor of astronomy at Warsaw University, Poland, and leader of the Optical Gravitational Lensing Experiment (Ogle), noticed that just such an event was about to occur near the centre of our galaxy.
The Nikon D600 has advanced video features that are ideal for those ready to embrace the world of HD-SLR video, as well as those already enjoying its benefits such as manual control, depth of field, low-light ability and lensing options.
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"Theoretically if you construct the elements we've made at terahertz frequencies, make them even smaller and then scale them up to optical frequencies, you could have perfect lensing at those frequencies, " said co-author Dr Willie Padilla of the University of California, San Diego.
Indeed, some at the meeting argued that if aliens were to use an astronomical phenomenon called gravitational lensing (in which the gravitational field of the sun bends and amplifies radio waves and light from Earth), human signals could be amplified to the point where even the light from cities would be visible.
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