The dark energy pushing our universe apart may not be what it seems, scientists say

Distant, ancient galaxies are giving scientists more hints that a mysterious force called dark energy may not be what they thought. Astronomers know the universe is expanding at an accelerating rate and they have long thought that a constant force called dark energy is what is pushing it apart. But findings published Tuesday by an international research collaboration are bolstering the suggestion first made earlier this year by the same group that there may be something else going on. By looking at the movement of galaxies over billions of years it appears as though the energy appears is changing or weakening over time. Distant, ancient galaxies are giving scientists more hints that a mysterious force called dark energy may not be what they thought. Astronomers know the universe is expanding at an accelerating rate and they have long thought that a constant force called dark energy is what is pushing it apart. But findings published Tuesday by an international research collaboration are bolstering the suggestion first made earlier this year by the same group that there may be something else going on. By looking at the movement of galaxies over billions of years it appears as though the energy appears is changing or weakening over time.  AP Technology and Science