Before the Big Bang, the Big Crunch?6 min read . Updated: 22 Dec 2010, 11:05 PM IST
Before the Big Bang, the Big Crunch?
New Delhi: Sir Roger Penrose is one of the most influential and eclectic scientists in the field of cosmology—the study of the universe.
Though an emeritus professor of mathematics at the University of Oxford, he is primarily a cosmologist and has done pioneering work in explaining the origins of the universe. He laid the mathematical foundations for several of Stephen Hawking’s ideas on black holes. Before that, he merged art and mathematics by explaining geometric patterns called Penrose tilings that inspired several works of artist M.C. Escher, known for creating three-dimensional illusions on canvas.
Penrose, who was in New Delhi for lectures, spoke in an interview about his Conformal Cyclic Cosmology theory—the main idea in his latest book, Cycles of Time: An Extraordinary New View of the Universe. The Big Bang theory on the origin of the universe, he said, offers only a limited explanation of what really happened. Edited excerpts:
Could you explain the currently accepted view of the origin of the universe and how your ideas differ?
The dominant view in cosmology is that the universe started with a Big Bang and it was followed by a kind of inflation, where the universe is supposed to have expanded by a certain amount, and this will explain certain features of the world we know. Now the scheme I am proposing is that the Big Bang was not the beginning. There was something which took place prior to the Big Bang. Other proposals suggest that this period (before the Big Bang) saw a collapse, or what is popularly called a Big Crunch.
(From this state) somehow, there was a Big Bang. I think that there was a previous eon (what we consider to be the entire history of our universe from the Big Bang to the accelerated expansion it seems to be indulging in), and this was among an infinite succession of such aeons where the remote future is simply the Big Bang of the next aeon. As the universe expands over time, all its particles cool down and lose their mass.
Therefore, the very broadly expanded future is indistinguishable from a Big Bang of the next aeon. So the universe somehow forgets how big it is. This is a strange concept. When there is no mass left it is not possible to distinguish time from space. The speed of light remains the same but big and small, long time and short time, all become equivalent.
So it’s a cyclic process, in that there is an expansion then a destruction and an expansion again?
Yes, the difference between my model and other cyclic models (that argue on similar lines) is that there is no contraction. The universe never collapses again and this process continues indefinitely.
So doesn’t one universe lead into the other?
Yes. In fact, the explanation I have given is a very verbal one. You do need equations. So I have those equations, which will carry you through what I call the crossover—from the infinitely expanded universe to the Big Bang of the next aeon. You see, people tend to think that the physics we need to understand the Big Bang is quantum gravity (an elusive set of mathematical equations that connects gravity, which operates on a macro scale, with the fundamental forces that govern atomic particles).
What I’m saying is that the classical equations are enough. We don’t need quantum mechanics, and it’s also observationally testable.
How will you make these observations?
There are different ways of attacking this problem. But the most immediate would be...to look for encounters between black holes in galactic clusters. I’m assuming that the aeon prior to ours would be similar in general terms to ours.
In other words, we have galaxies, clusters of galaxies, and at the centres of galaxies are black holes. And every now and then, galaxies will collide. It’s quite likely that our galaxy will collide with Andromeda (a galaxy neighbouring the Milky Way), not in our lifetimes thankfully, and it’s quite possible that black holes in one will collide with the black holes in another.
This would have happened several times in the aeons prior to ours. And when this happens, black holes will send out an enormous burst of energy, which is from our perspective virtually instantaneous. This will make its impression in the crossover between aeons and this can be observed in the cosmic microwave background radiation, which people refer to as the flash of the Big Bang cooled down by the expansion.
And there’s an awful amount of information in the cosmic microwave background radiation (CMB, a pattern of energy waves that telescopes picked up in the 1960s, and which offered conclusive proof that the universe was expanding as a result of an explosion).
Most of the analysis that has been done has been crude, and they don’t look at details of the kind that you might see here, such as the presence of concentric circular patterns in the CMB. The circle is the burst of energy and makes its mark on the microwave background, but since this same black hole is likely to encounter others, we are likely to see several such rings which are concentric.
A month or so ago, me and (a) colleague of mine, Vahe Gurzadyan of the Yerevan Physics Institute in Armenia, did some analysis of this and claimed to have seen evidence of this. He showed me his preliminary analysis and was describing how he was doing this. He told me that he was actually able to see many such concentric circles, all of which was very exciting for us. He published this but many people complained that the statistics was done inappropriately, etc., etc. We think that what we’ve done is probably correct, the main indication being the concentric nature of the circles.
Do you think experiments such as at the Large Hadron Collider (LHC) could throw light on such issues?
It may well do, because the LHC is aimed at looking for the Higgs (boson) particle (a hypothetical elementary particle believed to be responsible for bodies having mass, and the cornerstone of physicists’ understanding of how matter is structured). If not that, there has to be something else that’s responsible (for mass).
What do you think? Do you think this Higgs particle exists?
I have no idea. I don’t have much of an insight into the particle physics side of things. I would imagine it’s not as simple as that. I, in fact, spoke to Peter Higgs not so long ago, and I mentioned some of these cosmological ideas and he seemed interested and he suggested that there is an alternative involving a family of such particles.
I don’t know what the rationale behind this is. I’m sure the LHC will throw up matters of insight. You see, it has relevance to what I’m saying. This is looking at the time when mass comes into the universe. I’m looking at the time before this period.
You’ve written several books on the nature of consciousness. Can new techniques such as FMRI (functional magnetic resonance imaging) and PET (positron emission tomography) (imaging techniques that monitor electrical and blood flow patterns in the brain) give an insight into how the brain acquires consciousness and how we become the sentient beings that we are?
These are valuable tools but can only tell you where in the brain do particular activities (motives, instincts) happen but throw no insight into why and what is happening. There’s some other observations that I’ve been reading about that seem very exciting. And these are the studies of microtubules. The neurons are very complicated structures and not like mere transistors. Inside the neurons are cytoskeletons, which contain microtubules—small little tubes —and my colleagues in the US suggested that these tubules play a key role in consciousness. At this level, quantum effects might play a crucial role. However, the jury on most of this is still out.