Is this the same theory?

David Wiltshire, a theoretical cosmologist from the University of Canterbury in New Zealand. In 2007 he worked out a solution to Einstein's general relativity, which far from being radical, he claims is "radically conservative".

This is because, unlike other cosmological theories, it does not require altered gravity or other exotic factors. And it doesn't need dark energy.

According to general relativity, the presence of mass slows the rate at which time passes. So, for example, clocks on satellites tick very slightly faster than those on Earth.

Wiltshire suggests that the distribution of matter in the universe leads to larger differences in the flow of time than previously considered. It is this oversight, he claims, that leads to the false conclusion that the universe is expanding at an accelerating rate: "Such acceleration is fundamentally not there; it is an illusion brought on by trying to fit an over-simplified model of the universe."

Wiltshire's theory also accounts for another quirk. According to the Standard Model, the universe has not always expanded at a uniform rate. After an initial period of rapid expansion called 'inflation', it slowed down. Then, approximately 6.3 billion years ago, the expansion started to speed up again.