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Male voice: Novartis—committed to making innovative¹ medicines for a world of patients and their families, online at novartis.com

Novartis…. Think what's possible

Steve: Welcome to Science Talk, the podcast of Scientific American for the seven days starting April 26th. I am Steve Mirsky. This week on the podcast, Scientific American author William Zajc talks about quark soup—how physicists³ are getting an idea what the universe was like immediately after the big bang. Historian Joyce Chaplin discusses the man she calls the first scientific American. And I'll talk about a conference I attended on evolution education, where I spoke⁴ to Jennifer Miller⁵, one of the biology teachers directly involved in [the] Dover intelligent design trial. Plus, we'll test your knowledge about some recent science in the news.

First up, William Zajc. He is a physicist² at Columbia University here in New York City and also serves as the scientific spokesman for what's called the Phoenix⁶ experiment at the Relativistic Heavy Ion Collider—that's RHIC for short—at Brookhaven National Laboratory at Long Island. Michael Riordan and Zajc wrote the cover story for the May Scientific American called "The First Few Microseconds." I called Zajc at his office at Columbia.

Steve: Dr. Zajc, thanks for being with us today.

Zajc: Yeah! It's my pleasure Steve.

Steve: In your Scientific American article, you mentioned Steven Weinberg's famous book, The First Three Minutes and how back when he wrote that in—I think, it was in 1977?

Zajc: That's correct.

Steve: He said that he couldn't get into any detail about what was going on in the very first hundredth of a second; but in your article you talk about the fact that now we can.

Zajc: Yes! Well at the time Weinberg was writing his book, the theory of quantum chromo dynamics⁷—how quarks and gluons interact with each other—was just being developed and at about the same time; so this was realized that they now understood what would happen in the very earliest moments of the universe. Prior to that, the indications were that there was an ultimate temperature that you could not heat matter beyond—a certain point which is to start making more and more particles. We now understand that, that was an indication that in fact the quarks and gluons were coming into play and now we understand how to extrapolate that to the first few microseconds and even earlier after the big bang.

Steve: You have this collider out on Long Island and you basically, I mean, the concept is pretty simple. You smash two gold nuclei⁸ into each other at speeds approaching the speed of light and then you look at the carnage that results. So what does all that tell you?

Zajc: Well! It's a little better if you lived in a world in which you only had access to water in the frozen form, like ice cubes, and you didn't have any other way to heat the ice, other than to smash them together. And, in a way, if you think of the ice cubes being replaced by atomic nuclei—gold nuclei in this case—the only way we can see them melt into a gas or a liquid or quarks and gluons is by smashing them together. And you could imagine it would be rather difficult to find evidence of steam or liquid water by smashing ice cubes together; and correspondingly it's difficult—but fortunately not impossible—to find evidence for that so-called phase transition from one form of matter to another by colliding nuclei inside these very large detectors¹¹.

Steve: How big is the facility out on Long Island?

Zajc: Well! The accelerator is about a little over two miles around in circumference¹². And there are four experiments—there are two so-called small experiments with collaborations of about a hundred scientists; and two large detectors with collaborations each of around 500 scientists and engineers.

Steve: And you are the official spokesperson for one of those larger experiments?

Zajc: That's right! I am spokesperson for the Phoenix experiment.

Steve: What specifically does that experiment look at?

Zajc: Well! Phoenix is designed to look into the very interior of this region—if you like, to perform the x-ray imaging of the collisions that result. It's actually much more than that. It's the multipurpose detector¹⁰ that has the ability to look at all stages of the collision from the very first moments when the nuclei collide until the final decayed products emerge.

Steve: And so you use the sinology of looking at the liquid water and the steam based on the collision of the ice particles; so when you actually collide the gold nuclei into each other, what do you in fact get, and what does that then in fact tell you?

Zajc: Well! Perhaps the most surprising thing that resulted is the understanding that there really is a liquid form of this matter. For various reasons, people thought that the collisions would be more like dry ice rather than regular ice. If you let a chunk¹³ of dry ice to sit on your table top, it doesn't turn into liquid carbon dioxide, it turns into vapor¹⁴. And the prevailing¹⁵ sentiment and hunches¹⁶ in the community were that when we smashed our nuclei together that they would transition immediately into something more like a gaseous¹⁷ state than a liquid state; and instead we found that the behavior of the particles—when you look not at individual particles, but how they emerge as a swarm¹⁸ as droplets¹⁹ almost—they are much better described by the equations of hydrodynamics as if they were a fluid rather than some diffuse²⁰ gas.

Steve: So that's always great when your experiment gives you results that you didn't expect.

Zajc: Very exciting and also very challenging to try and understand where that's into the framework of quantum chromo dynamics and to go back and look at the calculations and understand which calculations made sense, which ones were an error; and the process of sorting that out has been extremely stimulating²¹ scientifically.

Steve: The Large Hadron Collider goes online next year and you are up and how does that fit into this work? Does that extend this?

Zajc: It will extend it and it will again help us in this process of sorting out which are—if any are—the correct models of the liquid state we think is formed in the accelerator at Brookhaven. The LHC will operate at a much higher energy and there are competing proposals that it will either truly reach something more like this gaseous state or the liquid behavior will persist at these much higher energies, so that's one the very first thing that we'll know when collisions start at the LHC and that will be a tremendous advance in our understanding.

Steve: And how long do we need to wait before we start getting results from that?

Zajc: I think 2009 is when we might see those results.

Steve: That's great, so just another few years and you'll get presumably even closer to the very first moments of the big bang.

Zajc: That's correct and while that's going on and we'll be busy exploring the details of what we are forming at RHIC and mounting new experiments to look with even more precision at the collisions in Brookhaven.

Steve: And RHIC again stands for?

Zajc: Relativistic Heavy Ion Collider.

Steve: Great. Dr. Zajc, thanks very much for being with us today.

Zajc: Thank you Steve.

Steve: Zajc's and Riordan's article, "The First Few Microseconds", is available free on our Web site, www.sciam.com.

Want to share some thoughts about the podcast? Let us know what you think by participating in our survey at www.sciam.com/research.

Now it's time to play TOTALL…….Y BOGUS. Here are four science stories, but only three are true. See if you know which story is TOTALL…….Y BOGUS.

Story number 1: Researchers say they can measure a child's stress level by testing the kid's drool.

Story number 2: While driving in Florida a couple of weeks ago, I twice had to avoid hitting iguanas²² running across the road.

Story number 3: A team of paranormal investigators²³ has found evidence of a ghost below decks on a ship in Mystic Seaport²⁴ in Connecticut.

And story number 4: Octopi or octopuses—however you prefer—use nerve signals traveling in opposite directions to form virtual elbows in their tentacles²⁷ when necessary.

We'll be back with the answer. But first, 2006 marks Benjamin Franklin's 300th birthday. The politician, diplomat²⁸ and publisher was also a first-grade scientist. Harvard University historian, Joyce Chaplin, has written a new Franklin biography that concentrates on his science. To find out more I called Chaplin at her home in Cambridge, Massachusetts.

Steve: Dr. Chaplin thanks for talking to us.

Chaplin: Thank you.

Steve: First the name of the book—The First Scientific American: Benjamin Franklin and the Pursuit of Genius. Let's tell everybody that you are not in anyway affiliated²⁹ with Scientific American;that's just a coincidence with the book titles.

Chaplin: Exactly! Franklin has been called an American so often, and the "First American," that I wanted to remind everyone that the science had something to do with his identity, so it was an independent finding, I swear.

Steve: And why the first scientific American though?

Chaplin: Because science was so important not only to his identity, but to the later career that he had as an American founder³⁰. He really had much more prominence³¹ and influence as a man of science than he would have otherwise; and certainly he had the most prominent influence of any American of his time because of the work that he had done on science; hence first scientific American.

Steve: April 29th, 250 years ago, Franklin was elected to the Royal Society of London, the most prestigious³² scientific society in the world. So, what earned him that election and why was that such a big deal in everything that happened after that in Franklin's life?

Chaplin: He was elected because of his work on electricity. His experiments and observations on electricity had been published in London, their first edition in 1751. On the basis of that, the Royal Society awarded Franklin its coveted³³ Copley Medal, still a very high award, which Franklin received in 1753; and that was followed up with an election, his election to the Royal Society in 1756 and that was an amazing honor. First of all, it was rare for somebody who was from humble³⁴ birth like Franklin to be so elected. Most of the time, this is an honor that went to gentleman who had been born gentleman—that is fairly high up on a social scale. It really did prove that Franklin was self-made as a man of science in a very significant way, so [it was] quite an extraordinary honor and done to recognize Franklin's work on electricity. After that point the honors never stopped. Franklin kept getting elected to other societies. He got honors increased. Nearly every kind of accolade³⁵ was given to him and really on the strength to that as well, he began to get important political positions. He had had some political influence thus far, but nothing like that [what] he got afterwards. Most significantly he became postmaster general for the colonies, a position for which he had really used his network in and out of the Royal Society in London in order to guarantee that he would get that job; and after that point his political influence really increased as well, so in some ways it's that publication of the experiments and observation and then the Royal Society's recognition of that important publication that made Franklin what he was.

Steve: So it's fairly safe to say that without Franklin, the scientist, we don't have Franklin the elder statesman of the American Revolution.

Chaplin: He would never have become famous and influential³⁶ without that work in science and he would never certainly have had the international reputation that would have allowed him to represent the United States in Paris quite [as] successfully.

Steve: You've written extensively about an area of Franklin science that may be as not as well known as the electricity and that's his charting of the Gulf³⁷ Stream. Can you talk about that?

Chaplin: Yes, that was a very interesting and long-lasting episode of Franklin's life. He was fascinated with the sea. He wanted to run away and be a sailor as a boy. And he didn't do that, but he did manage to investigate the ocean really throughout his life.Accommodating with his charting of the Gulf Stream, he and a cousin, Timothy Folger, did the first chart of the Gulf Stream in 1768; and he did, subsequently, two more charts of the Gulf Stream after that. I think their work is very interesting in a way that it shows that science was very embedded³⁸ in politics and public culture at the time. Franklin chartered the Gulf Stream and wrote about it initially³⁹ because he was Postmaster General and he was worried about the time that it took to post the mails—to get back and forth⁴⁰ across the Atlantic—and the Gulf Stream helped explain why it took longer going from England to the colonies than reverse. So that's a way in which science was very much part of Franklin's political life, his life in public affairs and that's really true all of his science, though I think the work on the oceans makes that immediately apparent in a way that perhaps electrical experiments don't.

Steve: That's really interesting. I had no idea that the marriage of one's political station and the direction of one's science might be connected in that way.

Chaplin: Well! I think that today we think of scientists as being very specialized⁴¹ and in some ways cut off from other fields, but in Franklin's day in the 18th century, science was really part of public culture. Scientific demonstrations⁴² were done in public, a wide array of people took an interest in science; probably the British monarch⁴³ best trained in science ever was George III, adds just to the indication again of the fascination⁴⁴ that science held for people. Another good example is just where Franklin seemed to have done most of his electrical experiments. He and the other members of the Library Company of Philadelphia who did these experiments seemed to have done them in part of the Pennsylvania State House, now Independent[ce] Hall and that I think is just a wonderful example of how a public building, a government building could be loaned basically as a laboratory in order for people to do science and it shows the way in which science is really not cut off from the rest of public life in a way that obviously it would be now.

Steve: Although we do, do anthrax experiments in the U.S. Capital.

Chaplin: Oh dear! (laughs) I wouldn't want to claim that Franklin's experiments were the ancestor of that.

Steve: (laughs) Right! Right! Dr. … (laughs) almost called you Dr. Franklin. Does that happen a lot? (laughs)

Chaplin: It [does] sometimes—I would say that I can't accept a compliment. (laughs)

Steve: Dr. Chaplin, thank you very much for talking to us today.

Chaplin: Oh! Thank you so much.

Steve: Joyce Chaplin's book about Franklin is called The First Scientific American: Benjamin Franklin and the Pursuit of Genius. We'll be right back

(Male voice: Novartis—committed to making innovative medicines for a world of patients and their families, online at novartis.com

Novartis…. Think what's possible.)

Steve: Now it's time to see which story was TOTALL…….Y BOGUS. Let's review the four stories.

Story number 1: Testing drool can tell you a child's stress level.

Story number 2: Florida roads are lousy with iguanas.

Story number 3: Paranormal investigators found a ghost at Mystic Seaport.

And story number 4: Nerve signals going in opposite directions enable an octopus²⁵ to temporarily form what amounts to a functional⁴⁵ elbow.

Time is up.

Story number 1 is true. Looks like drool gives away a child's stress level, not the quantity of drool. I always drool more when I am relaxed myself, but now researchers publishing in the April issue of the Journal of Social and Personal Relationships say that levels of the enzyme⁴⁶ alpha-amylase found in saliva—and thus a[in] drool—give you a measure of the activity of the sympathetic nervous system's fight or flight response and thus of stress.

Story number 2 is true. I personally had to swerve⁴⁷ twice in Florida couple of weeks ago to avoid hitting a couple of iguanas. One was on an on-ramp to I-95, so I am not sanguine⁴⁸ about that guy's current condition. People apparently⁴⁹ have released pet iguanas in Florida by the thousands and they reproduce and they are now everywhere, which is not good for native species. About 10,000 iguanas have overrun the Florida town of Boca Grande; known as <i>no es bueno</i>.

Story number 4 is true. Researchers have learned that an octopus makes a sharp bend in its tentacle²⁶ by contracting muscles based on the collision of one nerve signal sent from the base of the tentacle to the tip and another going in the opposite direction, the elbow comes in handy—sorry—for feeding. You can read David Biello's story about how the octopus does this on our Web site www.sciam.com.

All of which means that story number 3, the one about a team of paranormal investigators finding evidence of a ghost on a boat at Mystic Seaport in Connecticut is of course TOTALL…….Y BOGUS. But members of what is called the Rhode Island Paranormal Research group are trying to determine why various groups of tourists report seeing the same apparition⁵⁰ below decks on a boat at Mystic Seaport. The apparition is a man wearing 19th-century clothing and smoking a pipe. This type of apparition is technically⁵¹ known as an actor and the paranormal activity is a publicity⁵² stunt⁵³ which I have played into, but hey, Mystic Seaport is nice. You should go there, have a nice time. Radio reports said the paranormal investigators were bringing in sophisticated equipment such as infrared⁵⁴ cameras; you know, actually with what your average actor gets paid, there is no reason to assume that this guy can stay warm enough to show up on an infrared camera.

Next up, well … me. Last Friday and Saturday, I attended a conference called "Teaching Evolution and the Nature of Science". It was sponsored by the New York Academy of Sciences and took place at John Jay College here in New York City; and as you can probably tell from the title, the conference was aimed at biology teachers who are increasingly under threat all around the country by people who at the least want evolution out of classrooms and sometimes want decidedly nonscientific concepts like intelligent design taught in public school biology classes. Kansas has redefined science entirely⁵⁵ to include supernatural causation. Anyway there were some excellent lectures by scientists like Brown University's Ken⁵⁶ Miller, who were giving the teachers more of the factual ammo that they need about evolution; and there were talks by some of the people at the front line like Jennifer Miller (no relation with Ken Miller). I have more about the teaching evolution conference and how you can virtually attend the entire thing in a moment, but first I want to play the interview I did with Jennifer Miller. She is one of the biology teachers at Dover High School in Pennsylvania—ground zero for the latest and very ill-advised attempt to knock off evolution. Quick review: An antievolution school board wanted a statement denigrating⁵⁷ evolution to be read to biology classes. Miller walked out rather than read the statement, because reading the statement would have violated her professional code of ethics⁵⁸. Parents who did not want their children exposed to what amounted to religion in a public school science class sued the school board and[in] what became [known as] the famous Kitzmiller case. The defendants⁵⁹ were the antievolution school board. In the end Judge, John Jones, a conservative, church-going, nonactivist judge issued a scathing⁶⁰ 139-page decision for the parents and between the end of the trial and release of the judge's decision, the antievolution school board was voted out of office and replaced with a pro-science school board. Four of the witnesses in the Dover trial spoke at this conference, including Jennifer Miller. She gave a blow-by-blow account of the entire Dover case. I caught up with her right after the talk. That din⁹ you hear in the background is a few hundred people attacking the snack table between lectures. That's how you know you are at a real science conference. Anyway, here's Jennifer Miller.

Steve: What general counsel would you give to teachers all across the country for whom this issue can descend⁶¹ all of a sudden?

Miller: Be prepared, first of all. You know, go to symposiums, go to conferences where you learn the current state of evolution, the current evidences for evolutions; you can bring that into your classroom. Also be aware of some of the things like intelligent design that are trying to attack evolution so that you are prepared; Because honestly, we weren't prepared in Dover, you know, we didn't know until it came upon us, you know, what was out there. So be prepared, know what you're going to say, stand as a department; you know, if you are questioned about how to design [an] evolution [curriculum], stand as a department and, you know, maybe formulate⁶² something as a department that you know, you're going to say or your position or whatever; just be prepared for what's out there.

Steve: One of the things you brought up was the importance of taking really good notes on all the meetings that you go to.

Miller: Yes. We learned that very quickly because we were asked in our depositions⁶³ and things, you know, who said what, what meeting were you at; and we learned very quickly that, you know, they all mesh⁶⁴ together, so we had to document everything. We cut minutes, every piece of paper we got, we put the date on it, you know, when we got it and that kind of things. So we amassed⁶⁵ piles and piles of notebooks and things of papers.

Steve: What's it like there now? How I[ha]s the whole community sort of responded to what happened?

Miller: I know, from a teacher's standpoint, it's a much more positive environment to be in. Now that the new school board has been elected you know, there is always issues in every school building, you know contract issues and that kind of thing, but as far—I mean, the overall is very positive. The students are just glad that it's over, basically. (laughs) They were tired of being in the news and tired of being singled out; you know, every day they open up the paper and see more about Dover so they are very glad not to be in the news anymore.

Steve: You spoke about something funny that your principal said when you were (laughs) first told that you were all going to have to talk about intelligent design in [at] any rate.

Miller: She had written a letter to [the] assistant superintendent⁶⁶ saying that our teachers are not qualified⁶⁷ to teach creationism; they are qualified to teach evolution and science not creationism—we had no training in creationism, so how can we teach that in the classroom?

Steve: What was the response to that?

Miller: We didn't really get a response. (laughs) We just said, you know, we just know the letter was sent, so I don't (laughs), I don't know what the response was.

Steve: And you might not know the answer to this, but I've been trying to check every once in a while to see if perjury⁶⁸ charges have ever been filed against some of the defendants. You know what's going on with them?

Miller: No, I know there was an investigation⁶⁹, as far as I knew [knew] there was a investigation by the U.S. attorney, but I, you know, I am saying I haven't heard anything; and talking to some of the lawyers, perjury is one of the hardest things to prosecute⁷⁰, so where that will all come about, I don't know.

Steve: Because an accusation⁷¹ was made from a pretty high source—I mean, Judge Jones in the decision basically says they perjured⁷² themselves.

Miller: Exactly! Exactly! And then it was so gratifying at that point to know that he believed what we said; you know, I mean, you know, not what some of the board members were saying because they were, you know, opposite of what we were saying. So it was very nice to read the decision and realize that he did believe us (laughs) when we talked.

Steve: What was it like for you guys when you read the actual full Jones decision?

Miller: There was a lot of high fives, lot of hugging going on. It was right in the middle of the day when the decision actually came out.

Steve: But actually reading every word of it must have been transcendent.

Miller: Oh! It was. I, you know, went home and you know read it, you know. If you are worried about ever reading a decision from a judge, and there is lot of legalese, it was wonderfully written, I mean it was 139 pages, but very understandable (laughs). It was great.

Steve: This decision should be in all the anthologies, the best science writing anthologies that come out every year, because the science exposition in the decision is so good.

Miller: Exactly! Exactly! And it was—one of the lawyers told me—that it was lucky that he was the one that had to cross-examine some of the or to examine some of the plainest[plaintiff's] witnesses like Ken Miller, because he didn't have a science background. So, he you know went and asked them questions to make the science experts bring it down to the level of (laughs) sort of the common person, so that even the judge with no science background could understand what we're talking about; and it was obvious that he got it by the decision.

Steve: Yeah! His dissection⁷³ of the statement that was the whole crux⁷⁴ of the matter, the statement, the pro-intelligent design statement that was to be read in the classrooms, the judge actually spends many pages dissecting⁷⁵ that statement in the decision and it's really a wonderful thing to read. So, it so clarifies what all the issues were.

Miller: Yeah! Exactly! It takes, you know, takes it apart piece by piece and says why this part, you know, doesn't make any sense and why this part is, so it was great. You couldn't have asked for a more thorough decision.

Steve: Well! Jennifer Miller, thanks very much, I appreciate it.

Miller: No problem. Thank you.

Steve: In Jennifer Miller's talk at the Evolution Education Conference, she told the story about how one of the students of the school had painted an evolution mural and one day it just disappeared from the school. When one of the school board members was asked what happened to it, he responded, "I gleefully watched it burn". So, that gives you a little taste of the kind of thing that these people were up against in Dover. Anyway there are lots of terrific talks at the conference, which was put together by the New York Academy of Sciences. I put up more info about it in on our blog, which you can access at blog.sciam.com, and within a couple of weeks from today, audio and video of all the talks at the conference should be available for downloads. To get the links, just go over to blog.sciam.com and look for the story titled, "Teaching the Science." Also a couple of weeks back, I[o]n the April 12th podcast, we talked about a case in Canada concerning researcher Brian Alters, who was also one of the expert witnesses in the Dover trial. Alters wanted to do a study on whether the intelligent design movement had made any inroads in Canada and he had his grant denied because of the funding agency said he hadn't supplied enough evidence for evolution. Anyway, thanks to a couple of podcast listeners, Jared Spice and Sammy Zahabi. I think Zahabi is a spice, coincidentally. Anyway they wrote in with the news that the funding agency, the Social Sciences and Humanities Research Council has since clarified its position by issuing a statement that begins: "The theory of evolution is not in doubt, SSHRC," that's the Research Council, "recognizes the theory of evolution as one of the cornerstones of modern science and of our understanding of the world," etc. I put a link to the entire statement up in the same blog entry about the Evolution Education Conference at blog.sciam.com; the entry is called "Teaching the Science".

Interested in the inner workings of the human brain? Scientific American Mind magazine brings you breakthroughs in psychology⁷⁶, neuroscience and more. For a free preview, visit, www.sciammind.com

Well! that's it for this edition of the Scientific American podcast. Our e-mail address is [email protected]; and also remember that science news is updated daily on the Scientific American Web site, www.sciam.com. For Science Talk, the podcast of Scientific American, I am Steve Mirsky. Thanks for clicking on us.