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- WASHINGTON (Reuters) - Einstein has been proved right yet again, an international
team of researchers said Thursday. They said observations of U.S. satellites
orbiting Earth showed that a spinning body can curve space -- something
Albert Einstein predicted in his general theory of relativity. Einstein
said the spin of a body must change the geometry of the universe by generating
space-time curvature.
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- He called it ``frame dragging'' but it
is also known as the Lense-Thirring effect, after Austrian physicists Josef
Lense and Hans Thirring, who said celestial bodies that rotate, such as
the Sun, create a force that pulls space towards them. The effect is so
strong it should affect a clock rotating slowly around a spinning body.
Ignazio Ciufolini of the Universita di Roma ``La Sapienza'' and colleagues
tested and measured the effect by analyzing the orbits of two NASA satellites,
LAGEOS and LAGEOSII.
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- They used lasers to measure tiny changes
in the orbits of the satellites and concluded the Earth was affecting them
in a way that could not be accounted for by gravity or tidal forces. ``Based
on the analysis of the orbits of the ... satellites LAGEOS and LAGEOS II,
we conclude that the Lense-Thirring effect exists,'' they wrote in a report
in the journal Science.
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- ``This direct measurement of the Lense-Thirring
effect confirms one of the remaining fundamental predictions of general
relativity, that a current of mass-energy, such as a spinning mass, as
a result of its mass motion changes the geometry of the universe by generating
space-time curvature.''
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