Steinhardt, Ovrut, and their colleagues Justin Khoury of Princeton and Neil Turok of the DAMTP in Cambridge, England, call their model the ekpyrotic universe, from the Greek word for conflagration.
In the ekpyrotic scenario, the fifth dimension is finite in size and bounded on either side by a three-dimensional brane.
In a modified version of the ekpyrotic theory, posted Aug.
This is arguably a `new ekpyrotic universe' that appears to be more elegant than the old model.
According to Steinhardt, the ekpyrotic theory does everything that Big Bang plus inflation accomplishes.
What [the ekpyrotic theory] has going for it is a much closer relationship to string theory than any formulation we currently have of inflation," says Guth.
Another developer of the inflation model, Andrei Linde of Stanford University, takes a much dimmer view of the new work and has posted several papers on the Internet lambasting the ekpyrotic model.
Making a universe in ekpyrotic theory requires patience, notes Ovrut.
As a bonus, he notes, the collision described by ekpyrotic theory not only generates cosmic structure, it also creates the known families of quarks and other fundamental particles.
At least one empirical test of the ekpyrotic theory may soon be possible.
Big Bang plus inflation predicts that gravitational waves can have extremely long wavelengths, while the ekpyrotic theory does not.