What Is a Cyclic Model?

A cyclic model is one theory to explain the development and nature of the universe. It suggests that the universe is caught in a series of potentially infinite cycles; we may be living in the first universe that ever happened, or the 137th universe, and there is no way to be certain. Physicists have developed several different forms of the cyclic model, incorporating components of string theory and other advanced theoretical physics. The more scientists learn about the universe, the more they can test these theories and develop new ones in response to emerging evidence.

Under this model, the universe continually expands and crunches back in on itself in a series of cycles. Instead of the big bang, it experiences more of a “big bounce.” As matter shifts in the universe, it collapses in on itself to create a singularity, which starts expanding all over again to set off the next cycle. This could potentially occur infinitely, as the cycles sustain and regulate themselves.

The universe has no specified beginning or end points in a cyclic model. Instead, it is caught in a series of oscillations that repeat endlessly. Each oscillation may bring about a different distribution of matter, creating an endless assortment of universes. People or other life forms living in different cycles wouldn’t be able to access information about a previous or future cycle. Several scientists have posited a variety of mechanisms for the cyclic model, using the latest research results to inform their theories.

One advantage to this approach is that it accounts for some irregularities with the big bang model once favored by researchers. As people learned more about the universe, particularly about the presence of dark matter, the big bang theory no longer quite fit the existing evidence. This is common in science, where researchers develop hypotheses to explain the world around them, adapting as more information emerges. The cyclical model provides an explanation for what does not fit the big bang model; in the early 21st century, it was consistent with what was known about the universe.

Numerous other patterns in nature follow a similar cyclic model, illustrating that stable cycles are a common state for natural phenomena. Researchers study cycles ranging from the lifespan of parasites in waterways to the formation and collapse of galaxies. These natural patterns can interact with other cycles in complex ecosystems where multiple organisms and phenomena may be present.