Lawrence Krauss on Science

April 23, 2013

Transcript:

Ted Simons: The poll reveals that two of three surveyed think it's time to elect a new senator with just 21% in favor of returning McCain to the Senate.

Ted Simons: It's time now for our regular visit with ASU's physicist and best selling author Lawrence Krauss, who enlightens us every month with the latest science news.

Lawrence Krauss: Great to be back.

Ted Simons: Couple of big things to talk about including baby pictures from the big bang. These are kind of baby pictures.

Lawrence Krauss: they are. Unlike normal baby pictures where only the parents like to look at them, in this case there are pictures that everyone should be interested in, pictures that go back show us what the universe looked like when it was only about 380,000, years after the big bang. . 13.8 billion years ago. I say that now because in fact from these new baby pictures we have been able to learn new things that have changed some of the numbers slightly.

Ted Simons: what we're looking at now, this is a radiation view of what, the universe?

Lawrence Krauss: What you're looking at is first of all projection of the sky in all directions. You see projections of the earth. Take the surface of the earth and project it on a flat plain. Imagine taking a projection of the sky in all directions and projecting it on a plat plain. There would be a horizontal line where our galaxy sits. It would be right in that horizontal zone, in the equator of that image. Then the upper part of the image is the northern hemisphere of the sky and the bottom part is the owner hemisphere. Of course they are not real images but false -- they are real images but false color images of hot and cold spots in the radiation called the cosmic microwave, the after glow of the big bang.

Ted Simons: you know this is radiation because the radiation started when everything cooled down?

Lawrence Krauss: The universe was very hot in early times and so hot in fact that matter didn't exist in a neutral form. Hydrogen, which is protons and electrons, every time a proton tried to capture an electron the radiation was so hot it break it apart. Matter existed in a plasma, a plasma is opaque to radiation but then when the universe become 380,000 years, the radiation cooled below 3,000 degrees, a little warmer than Phoenix in July, then the matter became neutral and transparent to radiation, so that radiation is streaming at us from all directions from that time when the universe first became the matter in the universe first became neutral. Streaming at us in all directions and the radiation has cooled down. It was 3,00 , degrees. It's now three degrees because the universe has expanded by a factor of 1,00 since then an it's in the background wave. If you're as old as you or I, you've actually even it. Remember the days before cable TV?

Ted Simons: Yes.

Lawrence Krauss: back when TV programs went off the air and you saw static?

Ted Simons: First the national anthem, then --

Lawrence Krauss: The test pattern, then static. If you're desperate to watch TV as I was I waited until the static came.

Ted Simons: I hear you.

Lawrence Krauss: 1% of that static is actually radiation from the big bang.

Ted Simons: So you're literally being bombarded from something that's 13 billion years old?

Lawrence Krauss: Exactly. What's amazing is this radiation has been coming at us forever but wasn't discovered until 1965 in New Jersey of all places by two people who really didn't know what they were looking for. They were at bell labs building a radio telescope and that just meant they had a radio receiver and they put it up to the sky and kept getting noise. They got rid of what they called a white material inside, which is pigeon droppings, they still got the noise. They went down the road to some astronomers at Princeton who were very said because they were building an antenna to look for the noise. The two who discovered the noise won the noble prize for physics. The big bang really happened. It's not controversial. There's no need to worry about teaching it in schools. It really happened, and when we look at this radiation which gives us a picture of the universe we can tell all sorts of new things about the universe. This new picture from what's called the plank satellite, the satellite that was launched by the European space agency, it's been going around the last few years above the earth, measuring the entire sky and giving a picture probably ten times more accurate than any baby picture we have of the universe up to now. It's allowed us to know, for example, when I came on the show a year ago I would have said the age of the universe was 13.7 billion years approximately. Now we know it's closer to 13.8 billion years. We know that the amount of dark matter, dark energy is slightly different. On the whole it confirms everything we knew but there's some mystery still. That's what's interesting.

Ted Simons: I was reading about hot and cold spots, first of all can you see them in the image, tell where they are?

Lawrence Krauss: All the spots in that picture are hot and cold spots. The blue are colored to be colder regions. The others are hotter region. Those are small temperature variations. What's wonderful is those were the Primordial lumps we think were created at the big bang itself when could later collapse to form all the galaxies, stars, planets, aliens and TV broadcasters.

Ted Simons: So you go get to see what happened prior to that 300,000.

Lawrence Krauss: We think those were imprinted at the beginning of time. That allows us to test our theories about what the universe was like not when it was 380,000 years old but a millionth of a billionth of a billionth of a second old.

Ted Simons: So what you're looking at became stars, planets.

Lawrence Krauss: The question is how did it get there? What was the physics at the beginning of time? So that is what people like me get paid to think about.

Ted Simons: Not all questions are answered.

Lawrence Krauss: No, in fact more questions than answers. In fact there's weird things which could be statistics. The problem is we only have one universe. Most of us do anyway. As far as we know. Most of us experience. Some people may claim to experience more and I make a political joke but I won't. The point is because we only have one universe if these things are statistical it turns out there's a few more large hot spots in the northern hemisphere than the southern hemisphere. We wouldn't expect that. Is an an accident of statistics or is that significant? With a sample of one it's hard to say. If we had another universe -- we may have to learn more. There's open questions. That's what makes science exciting.

Ted Simons: something else exciting, it just looks like this big old thing but when you realize what it is it's remarkable. Now,.

Lawrence Krauss: We're very proud.

Ted Simons: yes.

Lawrence Krauss: Any baby picture. We're very proud.

Ted Simons: couple of earth-like planets found like what --

Lawrence Krauss: 12 hundred light-years away. Probably one of the most exciting discoveries of the keppler satellite, which is a satellite that's been up for a while, here on the screen you can see that for the first time not only has it been able to discover planets comparable in size to the earth they are actually located around the star slightly smaller than our sun, slightly dimmer, but at a distance in comparison not that different from the earth. One of them is days 150 days its year is days, the other is 260 days. They are in the region, in the right size and in the region we think liquid water could exist. In my mind they are the first sort of candidates for actual habitable planets elsewhere.

Ted Simons: You're saying 12 hundred lights years a way there's a sun not quite as strong as ours. 5,6?

Lawrence Krauss: six planets. Solar system not that different than ours.

Ted Simons: two of them, 62 E and 62 F--

Lawrence Krauss: Very good.

Ted Simons: Well, thank you. Very similar to earth.

Lawrence Krauss: they are a little bit bigger but that shouldn't get in the way. If you had to pick a place outside our solar system where you may be reasonably certain life could form, those would be the places, but that's just the tip of the iceberg there are 100 billion stars in our galaxy. Pretty well every star has planets around it. I would suspect at least billion habitable planets in our galaxy.

Ted Simons: I hear about the habitual zone and the Goldilocks zone.

Lawrence Krauss: If you look at our own solar system everything is just right. Mars is too small and too far away. Venus used to not be so hot but had a runaway greenhouse effect. It's too hot now. We're right in the region right now liquid water can exist on a rocky planet. That's just right. It's not going to be just right for long. This program can't go on forever. In 2 billion years the earth will heat up and be much like Venus right now. I know you'll talk about sustainability next. No matter what we do the sun will be 15% brighter in 2 billion years and we will no longer be in the Goldilocks zone. If life wants to continue we have a few choices, one, move to Mars or maybe to move the earth. We could do that maybe.

Ted Simons: Or maybe take a ride up to keppler 62E.

Lawrence Krauss: 12 hundred light years away After or three million year voyage you could do that.

Ted Simons: 12 hundred light years inconceivable. Is it possible, is it possible to ever travel at the speed of light or beyond?

Lawrence Krauss: We can't say it's impossible to warp drive. We can have a discussion next time about that. It doesn't violate the laws of physics but it's an academic question. To travel at near the speed of light would cost -- would take so many resources you would have to harness the power output of a star to get a space ship and just have the fuel -- if you wanted to take an existing spacecraft with existing rocket fuel and accelerate it to half the speed of light the amount of fuel required would be more than the mass of the entire visible universe. NASA may appropriate funds for it but it's for the going to happen. The point is we aren't going to be traveling in space ships at near the speed of light. It's an economically prohibitive thing but that means aliens are not coming here.

Ted Simons: I was just going to say. Doesn't that make the idea of space ships coming to visit us a little unlikely?

Lawrence Krauss: Not only a little unlikely, it's incredibly unlikely. It just hasn't happened. None of us want to be alone. That's why this is so exciting. We want to know if we're alone in the universe. There may be microbial life on these plan its but is there intelligent life elsewhere in the universe.

Ted Simons: Do you think there's water on these things?

Lawrence Krauss: There's a reasonable likelihood of water on these things. There's lots of water produced around stars. When we look around our solar system all the ingredients of life are there. Water, organic material an sunlight. We have discovered a complex basis of amino acids, some recent experiments in Berkeley showed that even more complex molecules could be created by chemistry on those comets. If you expose them to ultraviolet light you can create dipeptides, basis of what forms RNA and DNA. So not only would I not be surprised if there's water, I wouldn't be surprised if there's microbes. I would be surprised if there is intelligent life.

Ted Simons: What about sea creatures? If you have water wouldn't you have a sea creature?

Lawrence Krauss: First you have to make the microbes that make sea creatures. It took a long time to happen on earth. That is what I exciting, we don't know what's possible and there's a whole universe of things to find out. That's why it's fun to come on each week.

Ted Simons: what is the keppler mission going to do?

Lawrence Krauss: It looks at stars and it's amazing that it can do that, how the stars get dimmer when the planets go in front of them. A teeny planet goes in front of the star and you change the brightness change by 1%, on a regular basis. Then you can see if the stars move wiggly back and forth in response to the gravitational pull of the planet. They have confirmed several hundred stars but discovered over -- not stars, planets, over 2,000 planet candidates and what we're finding is that basically every star probably has solar system around it. It's really neat.

Ted Simons: last point, the constellation lyra, I guess --

Lawrence Krauss: I don't worry about constellations.

Ted Simons: But I love that stuff. Vega is the bright star you can see -- if I look at Vega I could be looking at somewhere within that constellation --

Lawrence Krauss: Somewhere in that constellation there could be stars and sea creatures and there could be in 12 hundred years they will be able to listen to this program.

Ted Simons: Well, lucky them. Good to have you here. Thanks for joining us.

Lawrence Krauss: Thank you.