The past and future universe
October 2010 – the TV science programme ‘Horizon’, examined the theories of what came before the Big Bang by several prominent physicists. The notion that anything could come before the Big Bang has been dismissed by many who cannot fathom such a concept or who still abide by a God-made universe. But thinking of a time before the Big Bang is no longer a fringe idea.
According to some theories, the Big Bang may not even have happened at all and our universe may have been preceded by another one. One factor in theorising the non-Big Bang was that of cause and effect. We humans can see the effect of the Big Bang; an expanding universe through which cosmologists can peer back 10 to the minus 34 (superscripted) seconds to after the Big Bang. But what caused its formation 13.7 billion years ago? What came before it? And what would it look like? Horizon queried the theorists.
Nothingness into Something:
Professor Michio Kaku thinks that the nothingness from which the Big Bang arose, needs to be redefined. While there’s a state of absolutely nothing (no time, space, energy, etc) there is also the nothingness of the vacuum, which in reality is only the absence of matter. In Kaku’s version of the pre-Big Bang universe, a high-energy vacuum existed where the energy temporarily transformed into matter. One of these transformations became self-sustaining causing a chain-reaction, which led to the Big Bang. So rather than absolutely nothing producing the universe; there was just nothing, which became something.
Eternal Inflation:
At Stanford University, Professor Andre Linde thinks the Big Bang idea is flawed. The universe is relatively smooth and ordered materially, not something that could have emerged from the chaos of a Big Bang. He now thinks that not only did Inflation greatly expand the size of the universe just after the Big Bang, hence the universe’s smoothness, but that Inflation was the creation event. Further, Linde posits Inflation as an eternal process with countless other universes, which sit in a ‘heavy vacuum’ superstructure, inflating from each other, like bubbles in Swiss cheese. Above all, Inflation has seen many of its predictions about the universe emerge, which some of the other theories have not.
The Big Bounce:
It is well known that Classical Newtonian theory and Quantum Mechanics do not mix, but Dr. Param Singh has discovered a possible paradigm-shifting mathematical equation that could explain the Big Bang. Classical theory breaks down when approaching Quantum levels, bringing with it problems with Infinity. But Singh’s ingenious mathematical formula using both Classical and Quantum theory equations revealed that the attractive force of the contracting universe became repulsive before a singularity was achieved. In other words, as the universe collapsed, before it could reach zero, the force became repulsive, rebounding to create a new universe. This Big Bounce could be an eternal and cyclical event making new universes each time. [But if Singh’s formula is so revolutionary, how come the world at large has not heard of it, á la the great formulae of Newton and Einstein?]
Black Hole babies:
What do you get when you mix Darwin and Einstein? Cosmological Natural Selection. Professor Lee Smolin is convinced that Black Holes are the progenitors of other universes. As with evolution, Smolin sees ancestor universes with black holes living and dying, sucking in matter and energy, and spewing them out into a new universe. Do universes evolve? Perhaps like Stephen J. Gould’s Punctuated Equilibrium, nothing happens for a long time and then –Bang! A new species of universe evolves?
Brane game:
Neil Turok, the Director of the Perimeter Institute for Theoretical Physics, believes that the universe sits on a 3D brane (short for membrane), which floats in a higher dimension with at least one other brane. At some point, the branes collide, releasing energy, and a new universe is the result. This is a sharp paradigm shift and an idea still in progress.
The Future Past:
What happens at the end of the universe? Professor Sir Roger Penrose sees the end of our cooled and expanded universe possessing no time or mass, just photons. The photons convert into energy, which at some point explode resembling a Big Bang event. However, this is no point of nothingness, the old remotely-stretched universe becomes the focal point of the new Big Bang, negating the need for an infinitely small singularity point. From our point of view, the explosion would look like a small origin point but in fact, a whole photonic universe would be the source. An elegant theory.
Waves and Strings:
Perhaps the most complex idea belongs to Dr. Laura Mersini-Houghton. Mersini-Houghton realised that the universe could be represented as a wave function and used with String Theory equations. Such an equation explained the whys of the universe’s birth and survival in relation to a Big Bang. But even more important is that her theory predicted three (now observable) separate and unexplained cosmological phenomena not seen by the other theories; namely, the existence of Dark Flow, voids in the Cosmic Microwave Background, and discrepancies with the temperature of space. These seemingly point to the effects of neighbouring universes.
How to prove them:
While these theories compete, there are at least two instruments which while seeking confirmation of the Standard Model could prove or disprove some of the theories. The Low Frequency Array (LOFAR) radio telescope, when built, will be able to see backward one billion years after the Big Bang and check for the randomness of material in the universe, verifying or disproving Inflation. Meanwhile, the Laser Interferometer Gravity-wave Observatory (LIGO) in Louisiana searches for gravity waves caused by the Big Bang. But any results could take decades.
The elephant in the room:
However, a main point not addressed among all the counter proposals was that the theories seemed very compatible on complicated levels, as if feeling around the proverbial elephant. The maths and philosophy may be different, but there were more commonalities, which did not seem to be appreciated and discussed. Each wanted their own theory to win out. Surely they all remember how String Theory started out as several strands only to be recognised as many pieces of one stringy puzzle.
For instance: Michio Kaku’s high-energy vacuum of nothingness resembles Penrose’s future photonic state of the universe. The resultant energy burst could manifest as Inflation or the repulsive Big Bounce of Linde and Singh, respectively. The effect is a Mersini-Houghton-type universe, with accurate predictive qualities for the existence of other universes. Whether the beginning and end of the universe is played out on branes is another matter, plus black holes may have a role in restricting or ameliorating such cosmic processes. Perhaps there are shared emergent properties which could be discovered.
While the origins, mathematics, resultant outcomes, and predictions of each theory are different, the over-arching themes seem to point to a complex relationship between all the theories. However, it seems that the stellar personalities involved are the real unknowns. Horizon will no doubt follow up on the theories depicted and hopefully by then the main contenders will resolve any commonalities and come together with one grand and unified theory.