Transcript

Professor Brian Schmidt - Interview with Brian Schmidt

Audio

You can also listen to the interview [MP3 12.6MB].

iTunes

Visit this channel at La Trobe on iTunesU.

Transcript

Matt Smith

Welcome to a La Trobe University podcast. I would be your host Matt Smith and my guest today is Professor Brian Schmidt, an astronomer from the Australian National University and joint winner of the 2011 Nobel Prize in Physics.  Thanks for joining me, Brian.

 

Brian Schmidt

My pleasure.

 

Matt Smith

Can you tell me a bit about the discovery that you made back in 1998?  How is the universe expanding?

 

Brian Schmidt

Well, 1929, Edwin Hubble went out and he looked at nearby galaxies.  And he noticed that these objects were moving away from us – the further away the objects were, the faster they were moving away from us.  And he told everyone that that meant that the universe was expanding.  To get that in your mind, think of a balloon that you blow up and you put a lot of little dots on it and as you blow up the balloon, you will notice that every dot on the balloon moves away from every other point.  The further away the dots are on the balloon, the faster they move apart, just like Hubble saw in the universe.  So when I moved to Australia in 1994, I wanted to do something big.  And what I decided to do was to take Hubble's experiment, and look back in time by looking at very distant objects.  So that meant I could go through and measure how fast the universe was expanding in the past, and compare it to what it was doing now.  And what we found, much to our surprise, was that the universe had sped up over the last five billion years.  That was a surprise, because we knew gravity should slow the universe down and for some reason, the universe was being pushed and what we think is, pushed by gravity – gravity acting on something we did not know was in the universe, which we now call dark energy.

 

Matt Smith

Was that looking at data that's been collected since the Hubble telescope?

 

Brian Schmidt

No, we had to go and gather the data ourself.  The reason is that the universe is like a giant time machine.  Light travels at 300,000 kilometres per second, which is fast, but if I look at an object far enough away, it will literally take billions of years for that light to reach me.  So what we were able to do was to look at exploding stars called supernovae for which we think we can measure their distance by how bright they appear very accurately.  And so, by looking at really, really distant ones with the biggest telescopes we had, we were able to look back five, eight, even ten billion years into the universe's past, and see what was going on.  So, that's sort of our time machine, to look into the back of the universe.

 

Matt Smith

And you mentioned dark energy – so does your findings confirm that dark energy exists?

 

Brian Schmidt

Well, before our discovery, dark energy wasn't really known about.  The expansion of the universe speeding up meaning that there was some way that stuff was being pushed, is best explained by the universe being full of energy.  That space itself has energy associated with it.  And it turns out Einstein's theory of general relativity says that that energy will cause gravity to push rather than pull, so our measurement of an accelerating universe indicates that 72 or 73% of the universe is this stuff that we did not know existed.

Matt Smith

There's a quote from the comedian Stephen Wright.  He said, black holes are where God divided by zero.  Do you think that there is stuff out there that can't really be explained?

 

Brian Schmidt

Well, certainly.  One of the big questions that I'm always asked, is, What came before the big bang?  And my honest answer is, I don't even quite know what the big bang was.  I know it's when things as we know it now started.  But I don't know what came before the big bang.  People are trying to figure out what came before the big bang, but at this point there's no real way to tell whether or not their thought make any sense.  But let's say they actually come up to the idea of, we think we know what started the big bang.  Then I can always ask the question, well, what started that?  I can always go through and abstract a concept out to the point where I can't know it any more.  And so, yeah, I have to live with not knowing everything about the universe.

 

Matt Smith

Well, closer to what your discovery here was, what's the end point of the universe expanding?  Do you have a theory?

 

Brian Schmidt

We can guess.  Right now, this dark energy pushes on the universe.  And it is tied to space itself.  So the universe is expanding, and as it expands, space gets a little bigger, meaning I make a little more of this dark energy, which means it can push the universe a little harder.  Which makes it expand a little quicker, which then makes more of this dark energy, which can push even harder.  And so it's sort of a runaway expansion.  And unless this stuff for some reason suddenly disappears, the universe is going to expand more and more quickly over time, so much  so that in the future, galaxies that we see right now will be moving so quickly away from us, or space will be expanding so quickly between us, that the light from those objects will no longer be able to reach us.  Space will be expanding so quickly that light will literally get stranded on its way between objects we can see now, and us.  So, that sort of tells us that in the future, we'll look onto a very dark universe.  Our own galaxy, gravity has already won that part of the universe, that tract of gravity is not causing our galaxy to expand right now, so we don't have to worry about this dark energy.  But the distant part of the universe, that will literally disappear over the next hundred billion years or so, so future cosmologists like me, who try to study the universe, will have literally nothing to look at.

 

Matt Smith

I'd like to talk to you about your Nobel Prize a bit.  What were you doing when you found out that you won, and what was your reaction?

 

Brian Schmidt

I have two children, 14 and 17, and my 14-year-old had a late night tai kwon do session and so they had just come in and we were cooking dinner at about 8.30 at night, and I got a phone call from a woman with a Swedish accent, who said, "Is this Brian Schmidt?"  Now I have some graduate students who are very good at playing practical jokes.  One of them had sort of foreshadowed something earlier in the day so I literally thought it was a practical joke, although when she said to me the second time, "Are you sure that this is Brian Schmidt?" and I said, "Yes, this is Brian Schmidt", and she said, "Well, let me put you on to someone here who wants to tell you something", and so then another Swedish accent came on and I said "Wow, my graduate student's pretty good getting all these people with Swedish accents to talk to me on the phone, and then it became very clear that this was really happening.  You sort of feel weak in the knees, I kind of felt a little sick, obviously very excited, and they didn't give me very much time to think about it, because they said, OK, we're making this announcement in six minutes now, can you stay on the line, we'd like to have you say some things when we make the announcement.  Yeah, it was pretty wild, and once the announcement was done, my phone just started ringing off the hook.

 

Matt Smith

Have you had time to do research or teach really since then?

 

Brian Schmidt

Well, I was teaching a class in the middle of this, so the next day my ANU Cosmology class, I arrived with about twenty five reporters, and a whole bunch of other people and did my best to do that class and I continued to teach that class through October and I will be teaching it as best I can this year as well.  It's a very hectic schedule I have.  So the interest both in Australia and around the world is amazing, kind of startling how much interest the Nobel Prize generates, and they're great in that respect, for science, but it is a little overwhelming.  It is hard to find time to do my normal things and one of the previous Nobel Prize winners, Peter Daudiu, who lives here in Melbourne, told me, just enjoy the first year, don't expect to get much done, and then you can take a hold of your life the year after.  And so I'm following his advice as best I can.

 

Matt Smith

Do you think that winning this award will influence the funding of science research in Australia at all?

 

Brian Schmidt

Well, it's certainly not going to do it any harm.  We've just gone through a very tough budget and you will notice that science is just about the only area in the budget that remained unscathed.  It didn't have massive increases but it was on a nice even keel, and one of the things I've really been trying to emphasise to politicians is, we need to make sure when we spend money in science, we spend it wisely, and try to do it in a sensible way, rather than what the politics of the day says.  So, I've been really working on them to really think hard about how to spend the money they do, more intelligently.  That being said, I think there are some places where we could invest more and the government has been listening and I'm hoping next year when we actually maybe have a little bit more money on offer, we can convince politicians to spend it wisely in science, because ultimately science and technology pay dividends about the future productivity of our economy, and that's why they're going to do it.  And so, we need to make sure as scientists we really work to ensure that we do help the long-term prospects of the country, so I think I've been pretty happy how things turned out, actually.  You know, I'm 45 years old, they're going to have to listen to me for many, many more years to come, so, you know, I'm patient and I will outlast any of the politicians in parliament, I promise you.

 

Matt Smith

Tell me about the Nobel Prize ceremony.  You had to go to Sweden.  What sort of experience was that?  And I understand you gave the King of Sweden a bottle of your wine from the vineyard that you have.  Is that right?

 

Brian Schmidt

Yeah.  So the Nobel Prize ceremony is an entire week in Sweden.  They call it Nobel Prize Week.  And it is the Grand Finals week of Sweden.  And I think it's wonderful that Sweden as a country has embraced the idea of having science and literature and the Peace Prize more of Norway, but actually partially part of Sweden as well, those are the things they choose to celebrate.  It's wonderful to be part of that.  And they gave you a real treatment.  They whisk you off the plane.  You have a chauffeur.  My chauffeur's name was Stieg, like the racecar driver, you know, you get to meet the King, and so what I thought would be fun would be to present the King with a bottle of my wine that I make up in Canberra, a Pinot Noir and so when he gave me my prize, right in front of everyone, he said "congratulations Professor Schmidt on the Nobel Prize on behalf of the Swedish Academy and thank you very much for the bottle of wine.  I'll have it in the next week or two."  So I haven't heard back whether or not he liked it or not.  It was really fun.

 

Matt Smith

Do you get a lot of time to make the wine any more still?

 

Brian Schmidt

I make sure.  I planted the vineyard in 2000, I was 33, on the idea that astronomy has a tendency to take over people's lives and I said, I want to have some therapy from astronomy.  I love astronomy but I need to have a more balanced life.   It's still there to provide some balance, and yes, I've managed to make quite a good wine again this year.  It's been a little harder but I've still managed to sneak it in.

 

Matt Smith

That's good.  What direction is your research taking these days?  I imagine it's moved on quite a lot.

 

Brian Schmidt

We still don't know what dark energy is, and so I'm trying to figure it out, doing little tests as best I can.  To do that, I have a program here in Australia with a new telescope called the Skymapper Telescope.  This is a telescope we started building after Mount Stromlo Observatory burnt to the ground in 2003, destroying all five telescopes.  And I was planning to do this project back in 2003, I was 18 days into the project when the telescope was destroyed.  To replace that telescope I started a project with this new telescope, much more powerful, and it's very challenging to get a telescope working, especially one that is so cutting edge as this one.  So it is more or less working.  It still has a few little niggles we're trying to work out.  But this telescope will be taking a digital map of the entire southern sky and allowing us to do many, many things, one of which is to find these exploding stars are used to map the universe, to find many, many hundreds of those, and to map out the nearby universe with precision much greater than we've ever been able to do before.  And that will allow us to test some of the ideas of this dark energy and see if it is like the dark energy that Einstein postulated in 1917, or if it's a little different.  The survey will also allow astronomers across Australia to go through and essentially get a treasure map of what's interesting in the sky and to use the great big telescopes that are typically located overseas, at least at optical wave lengths and in space, to go through and point at these objects and learn things about the universe – what the first stars were like, other planets like Pluto out there, dwarf planets as we now call them, and everything else in between.

 

Matt Smith

Is Pluto still a planet?

 

Brian Schmidt

Well, whatever you want to call it.  I figured, once a planet, always a planet.  So I was rather sad to see it demoted.  Not based on any science, just ultimately what we call a planet and what we don't call a planet.  It's a rather arbitrary distinction.  I personally didn't see any real need to change our thinking on that.

 

Matt Smith

That's all the time we have for the La Trobe University podcast today.  I'd like to thank my guest, Professor Brian Schmidt, and you can follow him on twitter on @cosmicpinot.  If you have any questions, comments or feedback from this podcast, or any other, then send us an email at  podcast@latrobe.edu.au.