The team studied over 200,000 galaxies has measured the energy generated within a large portion of space more precisely than ever before. This represents the most comprehensive assessment of the energy output of the nearby Universe.
All the energy in the Universe was created in the Big Bang, with some portion locked up as mass. Stars shine by converting mass back into energy, as described by Einstein’s famous equation E=mc2 . This study confirms that the energy produced in a section of the Universe today is only about half what it was two billion years ago, and they find that this fading is occurring across all wavelengths from the ultraviolet to the far infrared.
The fact that the Universe is slowly fading has been known since the late 1990s, but this work shows that it is happening across all wavelengths from the ultraviolet to the infrared. “The Universe will decline from here on in, sliding gently into old age. The Universe has basically sat down on the sofa, pulled up a blanket and is about to nod off for an eternal doze,” concludes team lead Simon Driver.