Lawrence Krauss

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World-famous physicist Lawrence Krauss of Arizona State University joins Arizona Horizon monthly to talk about the latest science and physics news.

Ted Simons: Scientists are moving closer to creating a way for objects to become invisible, and the Hubble space telescope may have spotted the most distant object ever. To discuss the science headlines, we welcome renowned physicist and ASU professor Lawrence Krauss, who joins us for his monthly appearance on "Arizona Horizon." Good to see you. Thanks for joining us.
Lawrence Krauss: Great to be back.
Ted Simons: I want to start with the business of an invisibility cloak.
Lawrence Krauss: I do like this. It's being perfected at duke. Don't get too excited.It would be great, you could wear it and be caulking head. It's not a true invisibility cloak. What's being done here, is to manipulate the materials so that lightweights, which are electro-magnetic waves will bend around the material and come back, so they will go around and come back on the other side, so therefore, what you will see is what's behind the material. When you look at light, it will bend around it and come back, and instead of being absorbed or reflected, it will bend around it, and you will see the scene behind it. Now, the point about this, is that it only works, of course, for certain ranges of frequencies of light. And, and, and if you use x-rays or anything else, you could see the object. It makes an object invisible for certain set of frequencies, and that's amazing you can do it. There are simple ways, simpler ways, and there is one in Japan, and I remember many years ago seeing one in California to make you invisible. If I put little, little TV cameras all over your suit, and had our t.v. screens, and cameras on the back side of the suit, and the front side of the suit, would show what the cameras on the back side of the suit were Hoarding, so there is lots of ways of appearing to be invisible. There was a house in California that had that in the front, large TV screens of the ocean behind it, so you would not see the house.
Ted Simons: That's almost subterfuse. I like that idea of going around.
Lawrence Krauss: Going around is relevant because the relevance, we're talking about galaxies. The idea is if you could manipulate light you could do strange and wonderful things, and what I think is the key message here, is that by using new materials, that have exotic properties, that you can design in the laboratory you can do strange things to cause light to go through materials, one of the things that, that we have not talked about, but a few years ago, there are materials that can make light travel at very slow speeds, through the materials, slower than you walk. And, and it's amazing. You can make light, essentially, stand still in materials, and so, manipulating the quantum properties materials, and nano engineering, is a huge field, and this is just one interesting example of what's happening.
Ted Simons: Let's talk about something else. You mentioned galaxies. The Hubble telescope, I'm not sure if this is, happened or not, and I'm starting to get like well, maybe, maybe not. $13 billion light years away? They saw something? What did they see?
Lawrence Krauss: What they saw was what are might be the beginning of a galaxy, it's an object that they estimate to be about 600 light years across, which is tiny compared to our galaxy, which is 100,000 light years across, and maybe less than, than 1% or 1, maybe .001 the mass of the galaxy, but we think galaxies build up by eating, cannibalizing small objects and building up, and this may be the precursor of one of the first galaxies of the universe. It's 400 million years after the big bang. Many predict they should not form until a billion years after the big bang. If we want to learn about the formation, we want to see these things. We're building the telescope that's designed to look at a wide spectrum of the galaxies. What's really neat about this galazy, that we would not have seen it. If we had not used a telescope that space created.
Ted Simons: Yes.
Lawrence Krauss: Because, the way that -- it's too faint to see with any telescope but we Ruse gravitational lensing, which is the fact that space is curved, and light rays will bend around them just like they do here. There is a theme here, but in this case, objects can be magnified, and that's exactly what's happened. Space, itself, has acted like a lens, by looking through a massive cluster of galaxies, we have seen the light of this very faint object, bent around and magnified like my glasses do.
Ted Simons: So how do you know the thing is 13.3 billion light years? You have the bending of this here, and space is expanding, and sun is coming this way, it's a moving target.
Lawrence Krauss: It's not quite a moving target because at these instances, objects are moving away from us very fast through the expansion of the universe, and the light from those gets shifted to the longer wave lengths, the faster they are moving away from us, and the faster they are moving away from us is, is, that's related to the distance from us. So, by measuring the red shift, the, the degree to which all the, the light in that object is stretched, and we see, see objects are made of hydrogen, and they emit the same colors of light you see in the laboratory here, except when they are moving away from us, all those colors get shifted to longer wave lengths, and red is the longest of the invisible spectrum so we call that a red shift, and by the size of that, we know how far away the object is. Because the universe is expanding. And this object is a red shift, which is so great, well, it's the greatest, highest red shift of any compact object.
Ted Simons: So basically, what the Hubble telescope saw happened 13.3 billion years ago?
Lawrence Krauss: We're doing cosmic archaeology. The object, as it looked 13.3 billion years ago.
Ted Simons: We were not here.
Lawrence Krauss: Well before the Earth and sun formed. And what's kind of neat is that the intervening massive cluster is billions of light years away so the galaxies, the light, the stars that are performing the task, many of them are dead. Because they were performing the task 5 or six billion years ago, and our sun is 4.5 billion years ago.
Ted Simons: What does it tell us about the universe? What are we learning?
Lawrence Krauss: It's too early to say. What this may do is confirm the notion that galaxies build up by, by this procedure called hierarchical clustering. They cannibalize other objects, and if structure forms that early, it will tell us about dark matter. It will tell, which is the, the dominant stuff in our galaxy and all. We don't know what it's made of, and we think that it's responsible for the formation of galaxies. And as we learn about how they form in the universe, it will put constraints on the nature of that.
Ted Simons: Interesting. And I am also hearing rumors, and I will believe anything whether it comes to science.
Lawrence Krauss: Got to be skeptical. You cannot believe anything.
Ted Simons: Mars' curiosity may have discovered something whiz, bang, big-time stuff here.
Lawrence Krauss: Yes. There is rumors and, and, and you should be very suspicious. NASA likes to, to build anticipation, and a few years ago they did for, for result, they were assuming they were going, they discovered life and it wasn't that, but, there are rumors that that, the curiosity Rover may have evidence that will impact on, on the possibility of existing or, or, well, in this case, potentially existing microbes. There were early reports that they had seen methane, it is produced by light but it does not last long in the atmosphere. So, if you see it, then it suggests that there is something producing it today. And, and there was a very early report that they had seen it, but it turned out to be a contaminant, and maybe they will have, have reports seeing methane, if they see that, that really suggests that there are microbes alive. That would be remarkable. But, you know, it could be something different. But, we're all, all hoping.
Ted Simons: I was going to say, because you never know what they are going to find, but the idea of existing Mike Roan, what does that tell us?
Lawrence Krauss: First, I would be very surprised, I figured we would find evidence of fossilized life on mars when it was hotter and wetter billions of years ago, but if there are existing microbes that, tells us that first, they can exist in this hostile environment. It tells us life, in some sense, are more robust than we thought and the conditions for life, including water, are present right now on the surface of mars, and of course, the big question, and we have talked about this before, the million dollar question is, is that the independent life? Did that develop independently or is it microbes that got polluted from you and me that got shot to mars maybe a million years ago?
Ted Simons: Is there any, any chance that when you find microbes, that they could be the remnants, the last gasp of life when they used to -- like, zillions of years ago they had a civilization up there?
Lawrence Krauss: It might be the, it might be life that goes back to the early hotter, wetter days when mars was a much more pleasant climate. Or, it may be just due to the fact that the material is transported back and forth between the Earth and mars, and so the big question, once again, is are they our cousins, or if they really, first, we don't know this. I want to make that clear. We're speculating but if there is evidence for existing life on Mars, that would be important, and the next step is to find out if it's our cousins. If it's life developed independently on mars, that means there is life everywhere from the universe.
Ted Simons: A minute left. The election over. Did I see a lot of scientists making, heading to Capitol Hill?
Lawrence Krauss: Not a lot. There is one scientist who I supported and, and know who is heading to Capitol Hill and another one from princeton. There are too few scientists, that would make two, I think two or three Ph.D. scientists in 500 people and, and as bill foster said, it would be great if more were in. We can understand what a billion means, for example. It's useful, when you are spending money. And these important issues, which I continue to say, are the most important issues you are going to be dealing with from energy to security to climate change. They need to be dealt with by people who are willing to face reality and not bury their head in the sand.
Ted Simons: Are we doing a good enough job of facing reality right now?
Lawrence Krauss: No. During the election, did you hear climate change, once talked about by either party, it's a, of vital importance, and we'll have a meeting, a public event from the origins project in February on climate change. The great debate so people should come and learn about the science.
Ted Simons: I was going to say, I saw a couple of headlines here recently that every time you see a headline, it's worse than we thought, worse than we thought.
Lawrence Krauss: It is. And the evidence is becoming clearer and clearer and more damning, and no one is doing anything about it.
Ted Simons: We'll see if your scientist buddies will get things done. Good to see you again.
Lawrence Krauss: Let's hope so.
Ted Simons: Well, it's good to see you again.
Lawrence Krauss: Great.

Lawrence Krauss;

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