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Science Matters with Lawrence Krauss

Airdate: March 31, 2016
Arizona State University Physicist Lawrence Krauss explains the latest science news in his monthly appearance.

Guests:
  • Lawrence Krauss - Arizona State University Physicist
Category: Science

Keywords: Lawrence Krauss, Arizona State University Physicist, science news,

View Transcript
Ted Simons: Coming up next on "Arizona Horizon" -- world renowned physicist Lawrence Krauss explains the latest science moves including the development of an artificial cell. And we'll hear about the challenge of veterans hoping to further education. All next on "Arizona Horizon."

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Ted Simons: Good evening. Welcome to "Arizona Horizon." I'm Ted Simons. Governor Ducey today signed a number of bills including a controversial measure that overhauls the state's campaign finance laws and leaves enforcement of so-called dark money expenditures to the IRS. The measure also allowed funds donated to one campaign to be used for another candidate. Critics say it rendered contribution limits meaningless but the governor says it simplified free speech laws and regulations. He also signed a bill prohibiting abortion inducing medication after seven weeks of pregnancy. The governor says the legislature acted in good faith and some changes may need to be made in a later bill. We'll have much more on the governor's actions on tomorrow's "Journalists' Roundtable" Time for one of our most popular segments, science matters with Lawrence Krauss. We learn about artificial cells, exploding stars and disappearing ice sheets. Here he is, our favorite physicist, Lawrence Krauss.

Lawrence Krauss: That's right. Only one. [laughter]

Ted Simons: Well -- you're still a favorite.

Lawrence Krauss: Exactly. I'll take what I can get. I'm pleased to be here.

Ted Simons: We have so much to talk about. We'll start with this idea of an artificial cell. Are we talking synthetic life?

Lawrence Krauss: Yes. We're talking in some sense the first kind of synthetic life. Actually you won't remember we talked a little bit about a few years ago the fact that Craig Ventor, his group had developed what they called the first form of synthetic life. They basically molecule by molecule recreate the genome of a small bit of bacteria and put it into the nucleus of another cell and got that cell to act like the first.

Ted Simons: Point of reference, this is not the cell you're talking about.

Lawrence Krauss: No. People said it wasn't really artificial life. All they did was put one form into another cell preexisting. These organisms have the fewest genes that are known, human beings have thousands and thousands. The one they were looking at had about 525 genes. They were trying to find what are the minimum number of genes that can allow something to live, which is a really interesting question if you want to understand the origin of life. They are working on one of these organisms but it reproduced relatively slowly, so they worked on another one called micro plasma. It reproduces every three hours basically. They took that organism and they started removing gene by gene using what they knew about life to try to produce something some new organism that might still be alive with fewer genes. They tried and it didn't work. They tried using what we knew about biology and it didn't work. What they were able to do, which is amazing, they cut the genes down into eight groups. They got rid of one at a time and put them back together to see if it would function. They kept removing them, sometimes there are two genes that do the same thing and if you remove both of them of course it doesn't function but if you remove one it will function. What they just did was get a synthetic cell down which has 473 genes. The smallest number of any organism. It doesn't correspond to any organism that has been on Earth before. What's even more interesting, if you're trying to create this, they don't know why it works. They just kept removing things by trial and error and finding out which things would stop it from being alive. Of the 473 genes, there are 139 they don't have the slightest idea what they do. So a third of them are necessary for that thing to live but we don't understand what they do which is really important because again, we're trying to understand the origin of life. If we don't understand what even the simplest possible organism what these things do it means we have a long way to go.

Ted Simons: Are we talking genome editing here?

Lawrence Krauss: No, this is something different. That's a different procedure which has become quite useful recently. I think it's called CRISPR, a new mechanism that allows you to edit genes, taking out one at a time or part of a gene at a time. That's useful for genetic manipulation. These people built this from scratch. They didn't edit a gene that was already there. They took molecule by moleculing like a Lego set, 485,000 molecules to make this 473-gene system. They literally -- like you type on your computer and a sheet comes out with letters and they turn the letters into molecules and they have the first cell that actually is alive. 473 genes, smaller than any known organism. It doesn't do anything but live but we don't understand what a third of those are for. But it's incredibly exciting because we can begin to look step by step now that we have this minimal organism and find out what it is that makes -- what does it mean to be alive?

Ted Simons: Are we closer to creating life from scratch?

Lawrence Krauss: Yes. This in a sense created life from scratch with a lot of guidance. But once we know what all those genes are for we will be able in principle to create life forms from scratch. Being alive will mean a totally different thing. I think we have to be prepared for that eventuality in the future. I think it's fascinating because we're really coming to grips with what it means to be alive, what it means for life to originate on Earth, elsewhere in the universe, perhaps, and eventually we're going to make new life forms and that's scary but we better be used to it because it's going to happen.

Ted Simons: Interesting stuff. Apparently there is an early flash of an exploding star is caught for the first time?

Lawrence Krauss: Yes. We have seen supernova explosions all the time. There's one exploding star. As we talked about before every atom in your body and mine, by the way this isn't what we see. This is an artist's rendering. You may say what makes it so special. One exploding star for every -- per 100,000 years per galaxy. That's not very often, but what has happened if you look out in the universe you see lots of them. If we look far enough away we can see exploding stars every day if we look at thousands of galaxies, but just seeing the exploding star is not seeing what really happens. It's the aftermath. When the star gets bright a day later we're seeing stuff way after the star has exploded. When a star explodes in this supernova, what happens is the core of that star collapses. It's about the size of the Earth. It collapses from the size of the Earth to the size of Phoenix in one second. A shock wave is sent out. When it collapses, by the way, the first signal is emitted through particles called nutrinos but the shock wave goes out at thousands of kilometers per second it's still inside the star. The star hasn't exploded yet. The inside has collapsed. The shock wave goes out and about 20 minutes later it reaches outside of the star. These stars are so huge, by the way, the Earth would be located inside them.

Ted Simons: Let's look at the artist's rendition.

Lawrence Krauss: What we're seeing is the rendering of what we actually see in these images, the moment when this shock wave first hits the outside of the star. The star goes from something like 20,000 times the brightness of the sun to several hundred million times. Shock wave, the star begins to boom and explode. It's really the moment the star begins to explode. All the action happens when the inner part collapses but when the shock wave reaches the surface that's what we're seeing for the first time. What they used was the Kepler telescope. They took pictures every 20 minutes of a whole slew of galaxies far away and saw two stars, one about 300 times the mass of the sun, one 100 times the mass of the sun, explode and one of the galaxies is 700 million light-years away, the other 1.3 billion light-years away. If you want to learn about these things, if you can take a picture of a car crash you learn about the collision. We're not seeing things happen days later, we're seeing the moment this thing penetrates the outer part of the star and how stars fall apart.

Ted Simons: Any surprises?

Lawrence Krauss: One of the two stars, you couldn't see that sudden flash from the shock wave. It was predicted to be there. The question is does it depend on the size of the star or maybe there's dust around the star but it was a big surprise that we only saw the initial flash in one of those two exploding stars. Really interesting because it tells us the moment when the materials that make you and I up left the star. The reason this inner part of the star collapses, the reason we're here is the outer part blows off and all the nuclear elements, iron, carbon, gets kicked out into space eventually merging into another star in the solar system.

Ted Simons: We got a few minutes left here. I know that you're big on climate change and global warming and this kind of business. West Antarctic ice sheet is melting faster than anticipated.

Lawrence Krauss: It is melting much faster -- well, no. In fact it's melting what we can now do is having models that show how fast it's melting. Earlier models showed it melting slower but in fact what these models have been able to do is mimic known periods over the last few million years when the Earth was warmer -- the Earth is warmer than it is now. It ocean levels increased six to nine meters, 18 to 27 feet. The question is how can we model those things. I just was in Antarctica in December. The sheet is disintegrating. The idea is it make take 100 years. The new models show that it could happen much quicker. The reason is quite simple. You have this ice sheet and it has this long, floating part that's sort of floating on the water. That buttresses it, because the sheath is sliding down the hill and there's water underneath it. This buttress stopped the ice sheet from going away but as global warming cause us that buttress to break off and when I was there I saw icebergs like 22 miles long which were parts of the floating ice sheet, then the rest can slide in and disintegrate. What this new model shows is that sea levels could increase by a meter this century. In fact even potentially earlier, it could get worse, and up to 15 meters, 45 feet, by year 2500, which means not just Miami but New York and all those cities are under water.

Ted Simons: So quickly, I keep hearing hundreds, maybe thousands of years, does this mean decades?

Lawrence Krauss: We're talking within the next bunch of decades the sea level could rise if the west Antarctic ice sheet deteriorates like it is by a meter. We're okay in Phoenix but I wouldn't buy property in Miami.

Ted Simons: They’re having problems now.

Lawrence Krauss: I know exactly. The thought that people are saying well, we don't have to do anything about this, that's what's ridiculous. The implications are amazing. It's worse of course not just for Miami but for the billions of people who live in low-lying countries in the hot areas of the world who are in impoverished countries who will not have a place to live.

Ted Simons: Is it reversible?

Lawrence Krauss: Well, everything could be addressed. What this study show is if we actually take action now we can limit the deterioration of the ice sheets to a smaller level, but the action is not -- when there's no action being taken now that are remotely comparable to what we need to do. Even the recent accord doesn't do the job.

Ted Simons: On that optimistic note, a real scream to have you here.

Lawrence Krauss: Glad I could make your day. You hear what the governor is doing, this is small potatoes.

Ted Simons: Thank you.