Endless Universe Chapter Three

Two Tales of One Universe

It was the best of the times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredibility, it was the season of Light, it ws the season of Darkness, it was the spring of hope, it was the winter of despair.

-          Charles Dickens, A Tale of Two Cities

For cosmologists, this is the best of times. Since the beginning of the 1990s, progress in the field has been phenomenal. One successful experiment after another has been performed that has enhanced our knowledge of the universe, making it possible to test competing views of its history. As a result, many ideas have fallen by the wayside.

In 1996, at an international meeting held at Princeton to discuss the long-term future of cosmology, many different models were still in play. Three years later, only the inflationary model, with the addition of dark energy, remained viable.

When the WMAP image appeared four years later, in 2003, cosmologists worldwide breathed a collective sigh of relief that the new findings were consistent with the sole surviving model. Astrophysicist John Bahcall, giving the concluding remarks at the WMAP press conference, accurately expressed the prevailing attitude: “The most revolutionary result obtained [from the WMAP image] is that there are no revolutionary results. WMAP has confirmed with exquisite precision the crazy and unlikely scenario that astronomers and physicists cooked up based upon the incomplete evidence.”

Bahcall described the inflationary model as “Crazy and un-likely” because the current version is a patch work quilt sewn together from disparate ideas added over the previous two decades, plus the assumption of a particular, odd mixture of ordinary matter, dark matter, and dark energy. “Incredibly, everybody got it essentially right”, he said, expressing a widely held view that since the inflationary model was the last surviving model, it must be correct.

At the time of WMAP announcement, the cyclic model was still new and unfamiliar. Bahcall and other Astrophysicists were used to comparing models that incorporated small variations on the basic inflationary model, differing in only one or two details. But the cyclic model is entirely different. It turns cosmic history upside down and introduces numerous novel and surprising elements at once. Some new elements come from fundamental physics, some from general relativity, and some from cosmology.

 As the cyclic model has developed and its principles have become better known, astrophysicists and physicists have begun to pay close attention. But in 2003 neither Bahcall nor most other astrophysicists were aware that the WMAP’s exquisite confirmation of the inflationary predictions was simultaneously an equally exquisite confirmation of the cyclic picture.