Shu's idea is that time and space are not independent entities but can be converted back and forth between each other. In his formulation of the geometry of spacetime, the speed of light is simply the conversion factor between the two. Similarly, mass and length are interchangeable in a relationship in which the conversion factor depends on both the gravitational constant G and the speed of light, neither of which need be constant. In other words, as the Universe expands, mass and time are converted to length and space and vice versa as it contracts.
The Shu universe has no beginning or end, just alternating periods of expansion and contraction. In fact, Shu shows that singularities such as the Big Bang cannot exist in this cosmos. During a period of expansion, an observer in Shu's universe would see an odd kind of change in the red-shift of bright objects such as Type-I supernovas, as they accelerate away. It turns out, says Shu, that his data exactly matches the observations that astronomers have made on Earth.
Since the accelerating expansion of the Universe was discovered, cosmologists have been performing some bizarre contortions with the laws of physics to make the Standard Model work. The most commonly discussed x-factor is that the universe is filled with a dark energy that is forcing the universe to expand at an increasing rate. For this model to work, dark energy must make up 75 per cent of the energy-mass of the Universe and be increasing at a fantastic rate, ignoring the law of conservation of energy in an attempt to square this circle.
With Shu's theory there's no need to abandon conservation of energy. However, he faces a major problem explaining the existence and structure of the cosmic microwave background, the echo of the Big Bang, something that many astrophysicists believe to be the the strongest evidence that the Big Bang occurred.
Shu's approach may well explain the Type-I supernova observations without abandoning conservation of energy but it asks us to give up the notion of the Big Bang, the constancy of the speed of light and to accept a vast new set of potential phenomenon related to the interchangeable relationships between mass, space and time.