Current cosmological theories include dark energy (without any matter involved):-http://phys.org/news/2016-03-dark.html-"Dark matter and dark energy •27% of the universe is believed to consist of dark matter. Dark matter is thought to be the gravitational "glue" that binds the galaxies together. No one knows what dark matter actually is. •5% the universe consists of known material such as atoms and subatomic particles. •The rest of the universe is believed to consist of dark energy. Dark energy is believed to be responsible for the current rate of the expansion of the universe."- Comment: Matt Strassler didn't mention this idea. A part of eternal energy? God?