Physicist Richard Lieu first theorized that gravity could exist without mass—now he’s got a new cosmological model that eschews the need for dark energy.

If the Steady-State theory is correct, both of these properties should be identical today to what they are at great distances: the Universe should be uniform in both space and time.

The steady-state flow is examined for a car-following model in which the acceleration at time t of a car attempting to follow a lead car is proportional to the relative velocity at a time t-Δ and in ...