TRANSLATION OF A SCIENTIFIC PROGRAM BROADCAST BY France-5 (a French state-owned TV channel). The program is available through the Internet on the ``Youtube'' website and it is also available on my website at the following address: http://www.lpthe.jussieu.fr/~roehner/FILMS/cobaye1.mp4 This translation is destined to the groups in which nobody knows French. If in your group there is someone who knows French it is much better to translate from French directly into Chinese. The reason is very simple. As my English is not very good, the English translation may not be as clear as the French text. GENERAL GUIDELINES: (A) You may do it in 3 steps: (1) Insert the subtitles (2) Insert a Chinese voice track (3) Repeat the experiment by yourselves and film it. This is the advice given at the end of the first experiment. (B) I would suggest that once you have inserted the subtitles, you test the subtitled film on 3 or 4 test persons, either university students or high school students. After they have watched the film that should be asked a number of precise questions in order to test what they have really understood. What follows is a version for subtitles. Because the viewers must have enough time to read them, we gave a simplified and shortened translation. For a dubbed version in spoken Chinese, it may be necessary to rewrite the dialogues so that they follow more closely the French dialogues. The program contains two different stories, each of which lasts about 5mn. It seems better to make two separate movies so that they can be watched and handled independently. Title: We are not only guinea pigs [this is a strange title even in French, I don't know what it means exactly; perhaps one would need to find a Chinese title which better reflects the content. For instance, ``Scientific adventures with Agathe, David and Elise'' or anything else] Subtitle: Magic or scientific? Is it possible to overcome the force of gravity? Perhaps it may be useful to include a short presentation of the 3 characters: * the girl with fair hair: Agathe (she is the team leader) -> A * the girl with brown hair: Elise -> E * the man: David -> D * Commentator: C =========================================================================== FIRST EXPERIMENT: A BALL ROLLING DOWN A SLOPE IN A STRANGE WAY. First images: The girls are reading scientific books: A reads ``Mechanical transmissions'' and E reads ``Advanced level physics'' 00:18 C: Now it's time for the ``cobayes'' team members to take a break. [I would suggest, we keep the word cobaye; replacing it by ``guinea pigs would sound very strange.] [Then, there are 2 sentences about the scientific books that the girls are reading -> not necessary to translate them] 00:20 A: One of the interesting topics are the cylindrical sliding waves. E: These are those that I prefer [ironical] A: In addition you should pay attention to the spherical bearings [ironical] 00:30 A: How are you David? A: David, D: What did you say? A: Do you know the Serica transmissions? [not an exact translation, but it does not matter] A: I'm just completely taken away by mechanical transmissions [ironical] D: Perhaps we could try to find out with the TV control? By the way, there is an extraordinary program on TV right now. It looks magical. Magical or scientific? Who knows? E: You are preparing something. What are you up to? C: David the magician is back and ready to show us another of his tricks. 1:05 [after rolling down the first ball] Scientific? 1:29 [after rolling down the second ball] Magical or scientific? 1:30 A: Come on, your ball has been doctored in some way. 1:32 D: May be, but how was it done? It's up to you girls to find out. 1:35 A: Don't worry, we will unravel the mystery quickly. 1:42 C: Through what mysterious means is David, our beloved crazy scientist, able to slow down the ball? 1:52 C: In order to repeat David's experiment, Agathe and Elise asked the technical team to set up a plane on which they may roll down the ball. 1:54 A: Here is what I have done. With my own little hands I have built a ball which contains bolts and now I'm planning to use this magnet. E: How clever! I didn't expect less from you, Agathe Lecaron [Elise calls her friend Agathe Lecaron; using both the first name and the family name is normally a mark of respect, but here the purpose is rather derisive and ironical.] 2:04 C: The team leader has decided to explore the solution of a magnetic attraction. 2:06 A: I'm pretty sure it will work. I'm convinced it is a magnetic effect. 2:08 E: So, if I understand your idea correctly, you think that in this way you will be able to control the ball. A: Absolutely. Remember he was moving his hands like this. 2:20 A: Let the ball go down 2:21 A: Well, wait. The ball stops indeed, so it works but in fact it works too well because the ball sticks to the magnet. 2:25 E: That's quite impressive Agathe Lecaron! 2:31 A: Elise, please don't discourage me, consider that it was almost working. Be optimistic! Wait a minute I will put my hands closer to the ball. E: Elise laughing. A: Please, don't laugh, it's not funny. 2:43 A: Well, I recognize that it is not very satisfactory, but I have also made another ball, just in case. 2:45 A: I have a big ball here and I have also a big magnet here. E: What do you have in your ball? A: There are other magnets. E: Very well. Do you wish me to hold the plane like this. 3:00 A: Well it works! E: Well done. A: Give a steeper angle. [Laughing] See how well it works. [Then, speaking to the ball] I wish you to stop. [the ball indeed stops] 3:05 C: But there is a little problem! 3:10 A: Was one of David's hands also under the ball? 3:11 E: His two hands were above the ball. 3:15 E: In my opinion it was perhaps merely an optical illusion? A: That's indeed perhaps a good idea. 3:17 C: Elise thinks that David has misrepresented the scene thanks to a camera effect. 3:25 E: Look, if the camera is horizontal, one sees the slope of the plane. But one can trick the image by inclining the camera. Can you please put the plane horizontal. Now, on the scren the plane seems to make an angle whereas in fact it is horizontal. 3:42 A: Excellent! 3:44 E: But wait a minute, there is still a little problem because the background behind you also makes an angle. 3:55 C: In order to remove this difficulty, the technical team brings a black screen. 4:00 E: Very good. Last little thing, you must take a position so that on the screen your body appears vertical. 4:06 E: Your position is fine, now take the ball and try to roll it down as David has done. 4:12 A: Well, now the ball no longer moves. 4:15 E: Indeed, this method does not solve the problem. Well, I'm sorry to say that, but it seems that we must accept that David has won. By the way, here he is. You can laugh David, don't you. 4:30 D: You have considered that the ball was just a kind of black box. In fact, you were far from the solution. What was inside the ball was not so simple. As a matter of fact, inside the ball there were two different things. First, a steel ball. Secondly [he shows the glass container] E: Honey? D: Yes, honey. 4:43 D: Put the steel ball into the black ball, then add the honey. [the ball is called a ``style petanque'' ball. Petanque is a game that is fairly popular especially in the southern part of France. Unless there is a similar game in China this seems difficult to translate.] 4:50 C: In order to better show what is going on in the ball, David will use a transparent ball. 5:00 D: Let's first wait until the surface of the honey becomes horizontal. 5:04 C: David lets the ball go. 5:15 D: As the steel ball moves forward, it pushes the honey backward, thus changing the center of gravity of the system. 5:23 C: It's an astonishing experiment but it can be repeated by everybody. 5:38 D: You can make such a magical ball at home. You can of course film your own experiment and show it to your friends on WeChat, QQ or other social netwoks. 5:50 A: Well, what can I say. We were not up to the task and we accept our defeat. 5:51 D: Do you wish me to give you a second chance girls? 5:50: A and E: Yes, sure! ========================================================================= SECOND EXPERIMENT: A MAGIC CHAIN: WHY DO ITS LINKS GO UP IN THE AIR? 6:00 [Start of the experiment] 6:20 D: Magic or scientific? 6:28 C: Will Elise and Agathe be able to unravel this mystery? 6:33 E: It would be nice to be successful in our first attempt. Imagine how David would be surprised and impressed! 6:39 C: In order to repeat David's experiment, the girls put a metallic chain into a glass. To be on the safe side, they asked one of their friends, a physicist named Frederic Restagno, to help them. 6:54: A: Thank you for coming Fred, for we are always somewhat puzzled by David's tricks. Are they scientific or magical? Now we will do an experiment and you will be able to tell us if we are searching in the right direction. What would be your advice Fred? Fred: Well, let's do it the same way as David. Let's see... Elise and Agathe: It fails completely. It does not work at all as in David's demonstration. The links of the chain do not go up by more than a few millimeters. 7:15 Fred: Indeed, it almost does not work at all. What I suggest is that we do a few simple experiments in order to understand what are the main variables. 7:29 Fred: Let's consider more closely the chain that you tried. The chain you were using does not look like David's chain at all. There are indeed little balls but the distances between them are much larger than in David's chain. So, let's do an experiment with balls which are closer to one another. We can start with a preliminary experiment by using pasta. 7:47 Elise and Agathe: Just ordinary pasta? 7:58 C: In order to see if the spacing between the balls is one of the key of the mystery, our girls will try to repeat David's experiment with a necklace of pasta. 8:10 A: What length do we need? 8:11 Fred: About 10 m. 8:11 E: That's a lot! 8:12 C: It took our girls many, many minutes to put all the pasta on the wire. 8:34 Fred: Remember that our objective is to understand why our previous experiment was unsuccessful. Here the pasta are much closer than previously, but the pasta are of course much lighter than the small iron balls of the previous chaim. So the question becomes: Is a shorter spacing sufficient? Let's try. 8:34 E: OK 8:40 A: It works sligthly better, but not very much. 8:45 Fred: It seems that shorter distances between the nodes helps but the nature of the nodes plays also a role. 8:53 C: Our girls decide to test another pasta chain but this time with a different kind of pasta. 9:07 E and A: These pasta work better, the chain takes off. A: Why did it go higher than in the previous pasta? 9:13 Fred: This chain is like a little train whose carriages would almost touch one another. 9:16 Fred: By the way, I brought a little train so that you can see how it works. 9:22 A: A real model train! F: Yes a real little model train. 9:40 Fred: Let's consider three successive carriages. What happens is that when one carriage goes down, the next one is pulled not only forward but also upward. It is this upward force which will move up the balls of the chain. 9:49: C: As a confirmation of this assumption the girls will examine more closely the chain used by David. F: In this chain, we can see the different elements that we considered so far. We can see that the little balls are indeed fairly close to one another. In addition we observe that their connections are fairly stiff. Look, it is impossible to make a very small loop. A: Indeed, one cannot make a knot. F: One needs at least 6 or 7 links to make a complete circle. Now, everything seems to be OK and we only need to try it out. 10:19 E: OK, I will try it but if it does not work I will feel ridiculous. A: Don't worry, it will work. E: Let it go. 10:22 A: It seems to work! F: It works indeed, but it is not really satisfactory. A: I will tell you: I wish a more convincing result. 10:38 Fred: There is a last parameter that we did not use so far, namely the height of the fall. With a longer fall, the balls will move faster and will pull up the rest of the chain. A: So, if I understand correctly, there is another parameter that we did not consider so far, namely the velocity of the links. 10:50 C: In order to test the influence of the velocity, Elise and Agathe will perform a last test by dropping the chain from an elevated platform. 10:57 A: David, come, we are here! 11:02 E: Watch closely to see how well it works. 11:06 D: So you understood the mechanism? 11:06 E: Indeed, and just by ourselves! D: Magical or scientific? E: Scientific of course! Are we not science girls? E: Are you ready David? Go on Agathe. E: Whoo! Beautiful, isn't it? 11:24 A: Just in order to show you that we can do it twice in succession, Elise will repeat the experiment. 11:36 E and A: Yes! Great! Look at that! 11:41 A: Was it successful? 11:42: D: Indeed, you can be proud of your achievement. 11:50: A: Do I understand that you admire what we have done? D: Indeed. A: That gives me great pleasure [ironical] --------------------------- COMMENTS by Bertrand Roehner [The purpose of these comments is to emphasize what can be useful for highschool or university students.] These films are amusing but they carry also several messages that are of importance in any scientific investigation. What are these messages? (1) First, one should not be afraid to fail. This fear is expressed by Elise when she says: ``if it does not work I will feel ridiculous''. In the rolling ball film Agathe and Elise fail repeatedly. In fact, one should not say that their expriments failed. Any experiment asks ``Nature'' a question. Here, this question is: ``Will the behavior of the ball be similar to that of David's ball?'' The result of the experiment tells them that David's ball was different. Contrary to computer simulations which succeed almost always (if done by clever researchers), real experiments may give unexpected results. This is precisely what makes them interesting. (2) Especially in the second film, Elise and Agathe tested separately the effect of several parameters: distance between the little balls, stiffness of the connections, height of the fall. This method follows an advice given in the 17th century by a French mathematician, physicist and philosopher named Rene Descartes. He suggested that in order to solve a problem more easily one should divide it into as many separate questions as possible. Incidentally, this is also what we do in software programming: the main program calls sub-programs which themselves call sub-sub-programs and so on.