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With Lisa Randall Interviewer: Shinji Mukohyama

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With Lisa Randall Interviewer: Shinji Mukohyama Interview with Lisa Randall Interviewer: Shinji Mukohyama Writing a Book Hoping Randall: It is really quite a lot People Change Their Way of time. It means giving up of Thinking about Science other things. I think I don’t Mukohyama: Thank you very do all other things as much much for making time for us. as I’d like to do. I am often Let me start by congratulating writing when I am traveling you on the publication of the ̶certainly at every available Japanese translation of your opportunity. Even I remember, second book.1 I really enjoyed I was sitting at the National helping in the translation of Academy of Science’s your book. meeting, which is a big deal, Randall: Thank you for doing and Bruno Zumino looked at that, it’s really important, me and said“, Are you writing because, as you know, it’s a your book?” I guess I was just difcult thing. They try very shocked that I was. Basically I hard, and so it’s really good to try to do whenever I can, but have a physicist look at it. still it ends up taking quite a Mukohyama: Yeah. I noticed bit of time, and then I have that translating this book took this chunk of time and you a long time and lot of work. have to do this. Some of it is Writing the book really took very enjoyable, but some of it much more effort. is like a big purpose. To write Randall: Yeah, that’s true. a book with one idea is not Mukohyama: So how did you so hard. I think for me it is not nd time to do this? that interesting, so I try to put many ideas into the book, and then integrating them into a Lisa Randall is Frank B. Baird, Jr. Professor of Science at Harvard way that it all makes sense. University. She received her Ph.D. That becomes challenging. from Harvard University in 1987. She became Assistant Professor in 1991 Each chapter was quite a bit, and Associate Professor in 1995 at and then guring out how to MIT. She held professorships at MIT (1998-2001) and Princeton University (1998-2000) before returning to 1 Harvard University in 2001. She is a Knocking on Heaven’s Door: How Physics and Scientic Thinking member of the National Academy Illuminate the Universe and the of Sciences (since 2008), European Modern World, ECCO Press at Academy of Sciences and Arts (since HarperCollins, September 2011; 2012), and many other renowned Random House, September 2011. institutes and societies. She was on Japanese translation: 宇宙の扉を the list of Time Magazine’s“ 100 ノックする, NHK Publishing, Inc., Most Inuential People” of 2007. November 2013. 12 Kavli IPMU News No. 25 March 2014 put all the stories together. So, Randall: I think some people yes, it took quite some time. get it. I think a lot of people Mukohyama: Did you start are very stubborn, and so they writing the second book soon have their way of thinking. after nishing the rst one?2 If you don’t say what you Randall: No. In fact, I didn’t are thinking, they don’t pay think I would write a book for attention or they think they a while. I think the original know it all. I tried very hard motivation was more about to speak to the middle, so sort of the frustration with the people could talk to each way science was presented, other. Some people appreciate more than just about the that. But, I think we have a physics, which of course I was long way to go. I think just in excited about too; the Large the terms the way things have Hadron Collider, Higgs Boson, come out, people in America and all of that. After reading just like that argument much the newspaper, and following more, they don’t like to nd the debates, and traveling this middle ground as much. a bit, it wasn’t always clear But, I pursued it anyway, that even people interested in because I think it’s science understood really how important. I think it science worked. And I was will be a little while asked a lot of questions after before things change. my rst book. So, I realized But, maybe, it’s changing a this could be a very nice book, little bit. I think there was a and then I started writing. But, little bit more attention to it was some years later̶it thinking scientically in recent was few years at least. years than there had been Mukohyama: So do you think before. Maybe it’s helping. the second book changed Mukohyama: Yeah. We need Interview the way people think about patience. science? Randall: Yeah, I don’t know, 2 Warped Passages: Unraveling the Shinji Mukohyama is Associate Mysteries of the Universe’s Hidden Professor at the Kavli IPMU. He Dimensions, Allen Lane at Penguin, studies theoretical physics and June 2005; ECCO Press at Harper cosmology. He stayed at Harvard Collins, September 2005. Japanese University from 2001 to 2004. He translation: ワープする宇宙 ― 5次元 supervised the translation of Lisa 時空の謎を解く―, NHK Publishing, Randall’s rst book2 and the second Inc., June 2007. book1 into Japanese. 13 Mukohyama: I see. But for there are subtleties, as you other people it was too new know, about how it gets probably? communicated and“ Does the Randall: Yeah, I’m not sure. modulus5 carry information?” I don’t know. I think maybe in the anomaly mediation also because of duality, scenario; because we really people thought maybe it’s wanted to have a scenario just something that’s already where it really worked, where known. I think it took a you didn’t have the leading little while before people order terms. It was a tricky appreciated that we had really thing. We realized you had to done something different. I have supersymmetry working could be wrong, but that was on the other brane. But in maybe the sense I had. But, the process we were working we were certainly enthusiastic. out the geometry, we saw we don’t have time. There are make sure, because in some It was also a funny thing this exponential, which is too many things that have to sense we were really like, though, because we were remarkable for people like us be done properly. “Why didn’t anyone see this nishing up our paper on who have thought about the Mukohyama: Right. But before?” But, I think we were anomaly mediation and hierarchy problem for years. I hope that the Japanese pretty excited. I don’t know sequestering.4 Of course you think about version of your book and your what we thought in terms Mukohyama: Right. that. But then, I was starting TV program and so on will of who pays attention. In Randall: So, we actually at the metric and I was change the way people think fact, in the beginning I don’t delayed these papers until we confused, because it looked about science and get more think people paid as much were done with that. like you could remove one of people interested in science. attention. Mukohyama: Oh, really? the branes, which was a very That’s what I hope. Mukohyama: Oh really? Randall: We were excited, but surprising thing. Randall: Oh, that would be Randall: People made it seem we wanted to nish the other Mukohyama: Yeah, it’s very nice. Thank you. I hope so too. like it was just another extra things. We also wanted to surprising. dimension modeling. We really make sure we understood all Randall: Certainly, when I Excited with the Idea of the had to make that clear. Raman aspects, and we also had the told people this, they thought Warped Extra Dimension gave a bunch of talks in the innite extra dimension. So it has to be wrong, because Mukohyama: Now, let us talk beginning. Then I started to we had three papers that we we are not allowed to have about science. Your theory of give talks, and then I think were thinking about at the an innite extra dimension the brane world scenario and people started learning. Also, same time. They were all very and because of theoretical warped extra dimension3 I think right then Mark Wise interesting. 3 is now very famous and is called it“ Randall-Sundrum” in Mukohyama: I agree. So, you Brane world is a physical setup in which matter and forces are conned considered as one of the most his paper. It was very good for actually have three different to a surface called brane. Warped spacetime geometry is a spacetime promising scenarios beyond us, because it made it clear it models based on the similar that would be at except for an the standard model. But, I was a different kind of model. setup. How did you come up overall scaling that varies with the position in a direction. Warped extra wonder what you thought Yeah, I think people didn’t with different ideas from the dimension is an extra dimension when you rst proposed this always appreciate right away similar setup at almost the along which the higher-dimensional spacetime geometry is warped. model with Raman Sundrum. that it was̶some people same time? It’s amazing. 4 Anomary mediation is Were you condent that this did, but I am not sure it was Randall: Well, in some sense communication of supersymmetry model would get a lot of immediately known. the math came up with breaking by quantum effects.
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