Scientists have found new evidence that an idea Albert Einstein regretted ever having may be key to solving a big mystery: why the universe is expanding at an ever-faster clip.

That idea is the cosmological constant, sort of a repelling influence in empty space. Einstein inserted it in his theory of general relativity in 1917. He later called it the biggest blunder of his life. But today, many scientists believe it explains the ever-faster expansion of the universe.

In Thursday's issue of the journal Nature, French researchers report analyzing observations of pairs of distant galaxies. Their results fit with the idea that the cosmological constant is driving the expansion. But cosmologist Michael Turner of the University of Chicago said still more work is needed to confirm that idea.

Explore further Dark Energy Measurement Sheds New Light on Universe's Expansion

More information: Christian Marinoni & Adeline Buzzi (2010) A geometric measure of dark energy with pairs of galaxies, Nature 468, 539-541 (25 November 2010) Christian Marinoni & Adeline Buzzi (2010) A geometric measure of dark energy with pairs of galaxies,468, 539-541 (25 November 2010) doi:10.1038/nature09577

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