Is the Universe stuck in a Groundhog Day?

April 19, 2005

The idea of a cyclical universe is controversial but a leading researcher believes we really could be stuck in a never-ending loop. Speaking at the Institute of Physics conference Physics 2005, Professor Paul Steinhardt presented new work which could reinvigorate research into future universes.

Scientists recently discovered that the Universe’s expansion is speeding up, and that the majority of energy in the universe must therefore be gravitationally repulsive “dark energy”. Professor Paul Steinhardt of Princeton University will explain how this could mean that the Universe is destined to repeat its own history.

Physicists propose several options for the future of the Universe, but most dramatic is the possibility that the current acceleration is the prelude to a period of contraction. The “big crunch” which followed would create new matter and radiation, triggering another big bang, and a rejuvenated Universe would emerge from the fireball like a phoenix from the flames.

Professor Steinhardt explained that what happens in the future could also have happened in our past. The big bang may not have been the beginning of space and time. Instead, the evolution of the universe could be cyclic, with regularly repeating periods of expansion and contraction.

If this theory is correct, it could help to explain one of the puzzles of cosmology – how the galaxies, stars and planets came into being. The big bang should leave a boring, featureless universe, but not if it was preceded by a big crunch. The random quantum fluctuations in the collapsing universe might be the very ripples which seed the galaxies in the subsequent expansion.

The cyclic picture can be tested using experiments which are already underway. Physicists are looking for propagating ripples in space known as gravitational waves. Professor Steinhardt says that the spectrum of the waves detected should reveal whether or not the Universe existed before the big bang.

Source: Institute of Physics

Explore further: Spitzer's SPLASH project dives deep for galaxies

Related Stories

Spitzer's SPLASH project dives deep for galaxies

September 10, 2014

(Phys.org) —A new survey of galaxies by NASA's Spitzer Space Telescope is taking a plunge into the deep and uncharted waters of our cosmos. In one of the longest surveys the telescope will have ever performed, astronomers ...

Experts cast doubt on Big Bang bolstering discovery

June 14, 2014

Astrophysicists are casting doubt on what just recently was deemed a breakthrough in confirming how the universe was born: the observation of gravitational waves that apparently rippled through space right after the Big Bang.

Recommended for you

How bees naturally vaccinate their babies

July 31, 2015

When it comes to vaccinating their babies, bees don't have a choice—they naturally immunize their offspring against specific diseases found in their environments. And now for the first time, scientists have discovered how ...

Image: Hubble sees a dying star's final moments

July 31, 2015

A dying star's final moments are captured in this image from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star's demise is still quite ...

Earth flyby of 'space peanut' captured in new video

July 31, 2015

NASA scientists have used two giant, Earth-based radio telescopes to bounce radar signals off a passing asteroid and produce images of the peanut-shaped body as it approached close to Earth this past weekend.

Exoplanets 20/20: Looking back to the future

July 31, 2015

Geoff Marcy remembers the hair standing up on the back of his neck. Paul Butler remembers being dead tired. The two men had just made history: the first confirmation of a planet orbiting another star.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.