Monday, July 30, 2012

Scientists only understand 4% of universe




Despite all the scientific breakthroughs and Nobel Prizes for discoveries, scientists seem to be no nearer to a possible answer to their main question - why did the universe appear?

­RT sat down to talk to Aleksey Filippenko, an American astrophysicist and professor of astronomy at the University of California, Berkeley, CA.

He was the member of the team that received 2011 Nobel Prize for discovering the dark energy that is speeding up the expansion of the entire universe.

And he believes that it could have sprung into existence without any divine help whatsoever.


RT: You maintain you do not need any divine help to explain how the universe came to be. So, what is your version?

Aleksey Filippenko: Let me start by saying that I am going to discuss the universe only from the perspective of a scientist, from an intellectual perspective. I am not going to be talking about whether there is spiritual God or a personal God or a purpose to the universe – these are questions that scientists can’t address. My own belief is that once you have the laws of physics the universe just keeps going on its own. And it could even be that the laws of physics are all that you need in order to get the universe to start from the very beginning – the “Big Bang”.

RT: What is then the origin of the laws of physics?

AF: That’s a great question – what is the origin of the laws of physics? I don’t know. That’s a question science can’t answer. What if the laws of physics have always existed and they give rise to a universe – our universe – and perhaps even multiple universes. That is a possibility, but it is a possibility that is sort of outside the realm of science because we don’t know of any way to experimentally or observationally test whether that is a correct hypothesis.

RT: Let’s start from the very beginning – what gave rise to the universe, why was there a “Big Bang”?

AF: So, what gave rise to the universe is an interesting question. We don’t exactly know the answer to that. But we have some ideas: for example, if there was a pre-existing universe then what is called quantum fluctuation – little bits of energy coming into existence for a very short time and then usually disappearing – well, those can occasionally give rise to a universe because if a quantum fluctuation lasts for a long time it can grow to a very large size. And that can essentially give rise to a universe. And that universe might then have quantum fluctuations that produce other universes. So that would be a never-ending sequence of universes arising as a result of just fluctuations in energy in existing universes. That is one idea.

Or another possibility is that there is some sort of a hyperspace, some sort of a mathematical space in which the laws of physics existed and then the universes just sort of pop off like little soap bubbles that a child might blow. So there might be all these soap bubbles which are like different universes in a much bigger hyperspace within which the laws of physics operate for unknown reasons. You see, it all starts with the laws of physics, but I can’t tell you where they came from. What is very beautiful to me is that a very small number of laws can explain the vast complexity around us. With the one exception where we just still do not know – and that is life and intelligence. We just don’t know. Biologists have not advanced far enough to understand exactly how life arose and how intelligence arises. But the mechanical universes – amazingly complex, yet explainable with a few simple laws.

RT: Scientists have just announced the discovery of the Higgs boson. What do you think? What does it tell us about the origin of the universe?

AF:  The Higgs boson helps to complete what is called the Standard Model of particle physics. There is a way we have to try to understand – electrons and quarks and neutrino and other kinds of particles. And Higgs boson was kind of a missing piece of the puzzle. Which, if it were not there, would mean that we would have to kind of start over. But the fact that it appears to have been found completes our picture of the Standard Model of particle physics. That is not to say that we understand everything. We don’t yet understand how gravity fits in with particle physics. Other than the fact that gravity pulls particles together. We also do not understand things like dark energy. The universe seems to be filled with a dark energy that is expanding the universe faster and faster – I helped to discover that. And the 2011 Nobel Prize in physics was given to the team leaders last year for that discovery.

So, we don’t understand the dark energy. There is also something called dark matter. It may or may not be some kind of fundamental particles that could be part of the Standard Model – we don’t yet understand. The Higgs boson is a very important discovery. But it does not solve all the questions that remain in physics. But it is a very important discovery. In a sense, it would have been more exciting as a scientist to me if it were not there because it would mean that we were not correct in our view of the universe. The surprises are more fun than the expected discoveries.

We expected to find that the universe is slowing down, just like I toss a water bottle up it slows down due to gravity of the earth pulling it down and eventually it stops and brings it back down. We expected all the galaxies to be pulling on each other and to be slowing down the expansion of universe. But instead we found out that the expansion is speeding up! That meant that there is something totally brand new that was unanticipated, that we don’t understand! And for a scientist that is more fun just confirming something that you already thought was there, something you already thought was true.

RT: Were there any unanticipated discoveries among scientists?

AF: I don’t think scientists will ever truly understand creation because I don’t think we will know where the laws of physics came from. But given a universe, given a universe can arise I think some day we may well understand dark energy and dark matter and the other constituents of the universe. We only discovered dark energy 14 years ago – the accelerating expansion of the universe. So it is no surprise that we don’t yet fully understand dark energy. Dark matter was only conceived a few decades ago. So again, we don’t yet fully know what dark matter is. But we have not been investigating it for very long. I mean, in hundreds of years who knows what we will know. We might have a full inventory of what is in the universe and how everything behaves. So we will know a lot. But we won’t quite know why it all happened and why there is something other than nothing.
Why are there any mathematical laws of physics rather than just nothing at all? I don’t know whether we will ever understand that. Scientists are only well-aware of 4 per cent of the universe – that is, we understand pretty well the nature of 4 per cent of the universe. The stuff that is made of atoms. Ninety-six per cent of the universe is made out of dark matter and dark energy. And although we know they are present we don’t know what their detailed properties are or why they are there. Or what exactly is going on.

In the past couple of decades there has been a true revolution in our understanding of the universe. What we used to think of as being everything is actually only four percent of the pie, if you think of a pie with slices. Four per cent consists of normal stuff of which we are made. And so you can see that our view of the universe as scientists changes. And that is a strength of science. Scientists are not afraid to say that they used to be wrong. Their view of nature was incomplete. We love finding new things!  We don’t take anything as an article of faith. Other than perhaps..

http://www.rt.com/news/universe-physics-laws-energy-329/