New type of dark energy could solve Universe expansion mystery

A previously unknown, primordial form of dark energy could explain why the cosmos now seems to be expanding faster than theory predicts. This second type of dark energy — the ubiquitous but enigmatic substance that is pushing the current expansion of the Universe to accelerate — might have existed in the first 300,000 years after the Big Bang. If the findings are confirmed, they could help to solve a long-standing conundrum surrounding data about the early Universe, which seem to be incompatible with today’s measured rate of cosmic expansion.