J-P.
Petit: Biography
...Jean-Pierre Petit was born in 1937. In 1961, he graduated from the National School of Aeronautics in Paris (specializing in fluid mechanics).
...
...At school, he completed a number of unpublished personal works on a supersonic disk nozzle and on very thin hypersonic flat jets, which exhibited many paradoxical features.
...In 1961, he was invited to join Princeton University. For the journey, he boarded the steamship Mauretania, the one built in England just before the Titanic. Fortunately, it was a good voyage, and no icebergs were encountered.
...At Princeton, he joined the James Forrestal Center, directed by Professor Bogdanoff, but his stay was very short.
...When he arrived at the laboratory, he found it deserted, as everyone had gone out for lunch. Petit’s curiosity got the better of him, and he decided to look around. He ignored the signs reading "restricted area, authorized personnel only" and discovered a very strange disk-shaped machine. He decided to inspect it, so he climbed aboard.
...When Dr. Bogdanoff returned from lunch, Petit decided to talk to him about what he had seen. Bogdanoff became angry:
"You're crazy," he said. "Do you know that is a top-secret machine?"
Petit replied:
"No kidding, it will never work. It is just a ground-effect machine; you will never be able to take off with that."
...The conversation turned sour, and Petit had to quit the university and leave Princeton immediately. Penniless, he earned his living in New York selling drawings in Greenwich Village in order to earn the money for his return ticket.
...The steamship he took for his journey back to France was the "Liberté" of the well-known French Line. This was to be its last voyage, as it had been sold to a Japanese company that wanted to convert it into a floating hotel.
...No icebergs were seen during the return voyage, only an autumn storm with an extremely violent west wind. The waves were 30 meters high, and the sea was covered in foam. Nearly everyone suffered terribly from seasickness. The distance between the crests of successive waves became comparable to the length of the ship, approaching 300 meters. Like the wind, the waves arrived from behind and on one side. The ship, which had been navigating at just about the same speed, suddenly started to oscillate. Petit remembers:
"On all the ups and downs, the ship inclined at 43°. Two people died on board. An old lady fell in her cabin and hit her head on the basin, and a steward who didn't have the presence of mind to let go of his tray smashed the top of his head at the far end of the corridor."
Petit was able to observe this phenomenon from an upper deck of the ship.
...The captain decided to turn west in order to face the very dangerous waves. Petit was fascinated by the storm. One night, he wanted to explore the lower deck, normally forbidden to passengers, to observe the raging sea at close quarters. Mountains of black water and white foam blocked the horizon. Suddenly, Petit realized that one of the waves was flooding the ship's bridge, which was becoming swamped with water, and he himself risked being swept overboard by one of the waves, left alone in the middle of the Atlantic Ocean, in the middle of the night, in the ship's wake. He barely managed to save himself.
...When Petit returned to France, he undertook his military service, became a lieutenant in the Army, and ran a military gliding club in Fribourg, Germany. In his spare time, he made 200 free-fall parachute jumps.
...Somewhat disappointed by his experiences in Princeton, he became an artist for several years. He made a living painting and engraving copper and lithographic stones in Paris. Then he joined a company located in the south of France that had a test site for powder-propelled rockets.
...But he quickly got bored with it and joined a State Research Institute. He worked on an MHD power plant, a short-duration system based on a so-called "shock tube" (a short-duration shock-driven wind tunnel). The latter produced a hot and dense argon flow for 200 microseconds at a pressure of one bar, a temperature of ten thousand degrees, and a velocity of 2500 m/s.
...Combining this flow with a transverse two-tesla magnetic field yields a strong induced electric field (VB) and an electric current flowing through wall electrodes and external loads. At such high temperatures, the electrical conductivity of argon is high enough to generate huge amounts of electric power density: two megawatts for an MHD channel as large as a beer can.
...We are now in 1965. People were interested in the high efficiencies of MHD power plants (theoretically: up to 60%). Laboratories were well-funded in all countries, and they spent money.
...MHD researchers dreamed of being able to couple their generators to high-temperature reactors (HTRs). Inert gases like argon or helium would cool the heart of the reactor and extract thermal energy from it. Adding 2% of cesium would increase the electrical conductivity.
...HTR experts refused to consider reactors operating at temperatures higher than 1500°. MHD needed 2000 or 2500...
...Then people thought about a two-temperature system (in the US: Kerrebrock, and in Russia: Shendlin and his coworkers). The idea is simple. A fluorescent tube is a two-temperature device. The gas, neon, is cool. Proof of this is that you can touch it with your hand. But the electric field gives large energies to free electrons. These electrons strike the fluorescent layer inside the glass wall, which therefore reacts, emitting white light.
...Americans and Russians thought that under certain adequate conditions, a two-temperature MHD generator could work, say at a gas temperature of 1500° and an electron temperature of 2500-3000° Kelvin. You get good electrical conductivity (which depends on electron temperature), good efficiency—in fact, good everything.
...But in 1964, a young Russian went to an International MHD meeting in Newcastle, U.K. The young E. Velikhov, who belonged to the Russian team, as a theoretician, prophesied:
"Your two-temperature plasmas will be fairly unstable. You will have plane electron density waves, transforming your working gas into a... capacitor, a succession of high and low electrical conductivity layers. The electric current will not flow; therefore, no electric power, nothing. 'I have calculated all that,' he said."
...Nobody believed him, but it turned out to be true. In Warsaw in 1967, Ricateau, the French builder of the "Typhée" plant in Fontenay-aux-Roses, concluded: "We face the wall of Velikhov's electrothermal instability."
...In 1965, Petit joined the Institute of Fluid Mechanics in Marseille, which was directed by Professor J. Valensi (now deceased). Copying the American Bert Zauderer, the French used shock tubes to produce a hot gas flow at the source, quickly driven towards small MHD channels. They proved to be relatively low-cost experiments. The two-tesla magnetic field was delivered by a capacitor bank. The MHD channel was built in Plexiglas, and the electrodes were made of red copper.
...In France, the French Atomic Energy Commission (CEA, the French department for atomic energy) held almost all MHD activity in "closed cycles." But their huge generator, "Typhée," in its large room, turned out to be unstable, like all its counterparts around the world. The electric power output was close to nothing.
Then the guys at the CEA said:
"Why don't we try to simulate that with these small shock tubes, in the lab in Marseille?"
...The idea came from a young student of Kerrebrock: Solbès. In Marseille, the contract was rapidly signed up, although nobody there knew what a two-temperature generator was. Recently hired, Petit learned plasma physics. In 1967, Sutton and Sherman had just published their excellent book (McGraw-Hill) entitled "Engineering Magnetohydrodynamics." Petit understood the problem, built, and published his own theory of Velikhov's instability and had an original idea. He discovered, through his theoretical studies, that when the plasma becomes "fully ionized," if fast enough, the instability does not occur. The ionization stabilizes the plasma. This phenomenon was rediscovered fifteen years later by a Japanese researcher, who called it "climbing Mount Fuji" (due to the peculiar shape of the instability growth rate curve, looking like the famous Japanese volcano).
...In 1966, the experiment calculated by Petit was fully successful. For the first time in the world, an MHD generator worked with two temperatures and large power output, in stable conditions. Gas temperature: 6000°, electron temperature: 10,000°. Output power: two megawatts (during 200 microseconds...).
Petit's colleagues were skeptical. But Petit said:
"Let's put 2% of carbon dioxide in the gas. It will absorb the energy of the electron gas, transforming it into vibrational energy and radiative output. The process will be very fast, due to the large cross-section of CO2, and I have been able to compute that."
...Once again, Petit's predictions were sound. He confirmed that he was a good prophet and was able to present his work at the International MHD Meeting in Warsaw in 1967. Later, the temperature of the gas was successfully lowered to 4000° Kelvin. The stability of the plasma was confirmed by photos taken of it with the first available American electronic camera.
...The director of the lab was enthusiastic. Everybody thought that this was the solution, and all dreamed of lowering the gas temperature to 1500°. Of course, the shock tube is just a simulator. But people thought the idea was great and should solve the problems of the "big brothers," the full-size MHD converters.
...The lab's boss decided to run the experiment on his own, as usual. He put his own team on the plant built by Petit with his own hands and relegated him to a small room under the roof. There, Petit calculated again and laughed: the boat was a leaky boat. The theory showed that this method would not allow them to make the gas temperature lower than 4000°. All that excitement for nothing...
...During the next few months, Petit worked like hell to build his "lifeboat": a PhD thesis based on the kinetic theory of ionized gases. He knew he would have to give up seven years of hard work there and leave the lab.
...Downstairs, things didn't work so well. The boss's collaborators had made many errors and almost destroyed the MHD converter. Valensi ordered Petit to come back and rebuild the almost destroyed machine. But it was too late. Petit's PhD thesis had come to an end, and he left the lab, which sank. Tired of all that noise, Petit decided to transform electrons into stars in the equations and join the Marseille Observatory. (Practically, for the specialist: transforming the Boltzmann equation into the Vlasov equation, whose second member is zero).
He has worked there for more than 25 years.
...He wrote 30 books. Some were translated into English (The Adventures of Archibald Higgins). These books were printed in the US, England, Germany, Italy, Portugal, Russia, Poland, and... Iran.
...In the little stories of the Iranian Ayatollah, you find the heroine Sophie scantily dressed, and they exercised their right to make her dress decently as customary, with a chador. An Iranian artist took charge of this operation for her. Iran is not the only country that exercises these changes of clothing for the heroine. The second country was America. When these books came out in the U.S.A., they were taken by the department of mathematics at the University of Berkeley. Petit came to this University to give a lecture, and he brought with him the books already printed in England. He offered the books to the library, which made two types of books available to the students, all in English. Some carried the words "cleaned version," and the others carried the words "original version."
...It was twenty years ago. These issues are, without a doubt, difficult to find now. The series includes:
- Here's Looking at Euclid
- Computer Magic
- Everything is Relative
- Black Hole
- Big Bang
- The Silent Barrier
- Run, Robot, Run
18 titles were printed in France.
...In 1977, Petit discovered the first micro-computers, the Apple-II. He wrote the first computer-assisted 3D design program (Conception Assistée par Ordinateur or CAO), which worked efficiently on small systems (48K, 64K). He sold 1,500 copies of this software.
...During the next 8 years, he ran a computing center. At the same time, he learned modern geometry with Bernard Morin, a famous blind mathematician, and drew the eversion of the 2-sphere. He also invented a new eversion of the torus and published this work at the French Academy of Sciences. He showed that the meridian lines of the mysterious Boy's surface can be ellipses. This would later enable Apéry to build the first implicit equation of the surface, of the sixth degree.
...In 1975, Petit belonged to the Marseille Observatory. But the old MHD ideas still ran around inside his head. In 1965, during the MHD experiments, the slowing down of the plasma in the MHD channel was so strong that a front shock wave occurred and moved to the input of the channel. This was due to the Lorentz force JB. Producing electric energy slows down the gas: its kinetic energy is transformed into electricity.
...The higher the electricity production, the higher the gas slowing-down effect. As predicted by Petit, a shock wave should appear, and it did.
...Later, at the end of the sixties, clever and low-cost acceleration experiments were carried out in the Fluid Mechanics Institute of Marseille by two researchers: B. Fontaine and B. Forestier. They showed that using the MHD converter as an accelerator, the velocity of the argon plasma (2,750 m/s when entering the channel) could grow up to 8,000 m/s in a ten-centimeter-long MHD accelerator.
...But at the beginning of the seventies, MHD research stopped in all countries.
...In his observatory, Petit was still thinking about the marvelous MHD world. One day, he said:
"If having an effect with the Lorentz force is intense enough that I can produce a shock wave, why can't I cancel a shock wave, located in the front part of a body moving in a gas at supersonic velocity, just by sucking this gas with a suitably designed Lorentz force field? In a word, is shockless flight possible at supersonic velocities?"
...The idea seemed completely foolish to conventional fluid mechanics specialists. They said:
"You must have a shock wave system."
...Petit was not convinced. When he attended his aeronautical school in Paris, he used a water free-surface flow analog simulator. Today they have completely disappeared from universities and labs. But, in the sixties, one used it to simulate the shock wave system around, for example, a flat wing:
...If some readers are interested, some information can eventually be given on that website about MHD topics and shock wave cancellation.
...In short, in 1976, Petit calculated the parameters of an MHD experiment, used a one-tesla magnetic field, water plus hydrochloric acid, free-surface flow, electrodes, and canceled the water wave located in front of a one-centimeter model.
...Later, he directed a PhD thesis in the field, that of Bertrand Lebrun.
...For the fluid mechanics specialist, shock waves occur because "Mach lines focus":
...Where Mach lines accumulate, shock waves tend to grow. But the Lorentz force changes the local Mach angle and the local Mach lines system. With his student, Bertrand Lebrun, Petit showed in 1982 that through a convenient Lorentz force field, the self-crossing of the Mach lines could be avoided, so that the shocks do not form.
...Furthermore, all that could be experimentally tested with a transverse magnetic field and a wall electrode set. Petit and Lebrun presented the work at the 7th International Meeting in Tsukuba, Japan, 1987 (but, due to lack of money, they couldn't get there).
...Lebrun computed the field with a set of Macintosh computers, old ones belonging to colleagues of Petit. Each night, each machine worked on a piece of the field, and each morning Lebrun picked up the results as he passed by with his motorcycle and synthesized them on his own Macintosh. An original multiprocessor system.
...Anyway, the calculations were quite convincing. Petit had planned to test it with a shock-driven channel, as usual. These old systems were almost obsolete, but a lab located in Rouen, France, still owned an old one. Petit convinced the French CNRS (Centre National de la Recherche Scientifique) to support his research, and an MHD program was planned, with some financial support. The idea was simple. The old shock tube provided a short-duration (200 microseconds), hot (10,000°K), and dense (pressure: 1 bar) argon flow. In a first step, a schlieren system, based on the light of a small laser, showed the shock wave system around a flat wing with a sharp edge.
...Then, during another test, MHD would be operated with an adequate magnetic field (a 2-tesla field provided by a capacitor bank) and suitable electric discharge in the plasma through wall electrodes (also due to capacitor discharge). Then one might have expected that the Lorentz force would cancel the wave, especially the front waves.
Petit:
"I'm sure this would have worked successfully on the first test. All was carefully computed..."
...But the French Army stopped all that. The military were very much interested in the concept for their own use, but their underlying idea was... a supersonic cruise missile, and perhaps something else, who knows.
...At the end of the eighties, Petit discovered that the reason of state was a solid reality.
...Nobody can fight against the Army. He finally gave up and shifted towards theoretical cosmology in 1987.
...In 1987, Petit came to the Department of Fluid Mechanics at Berkeley, whose director, now retired, was his old good friend Tonio Oppenheim, who invited him to give a lecture about MHD and shock wave cancellation.
...In the same room, another colleague named Kunkle was seated. He was the director of the particle accelerator at Berkeley University. During Petit's lecture, he laughed all the time. Finally, Oppenheim, puzzled by this colleague's unusual behavior, asked him:
"Dear Professor Kunkle, we have been friends for many years. You are disturbing my friend Petit's conference, why?"
"Sorry, it's just too much for me. Petit is explaining, to all these young students, in clear words, a lot of research which is currently being held at the Lawrence Livermore Laboratory. But there, they are considered highly classified. In fact, so classified that I am not authorized to tell you one word about it. But they are... very similar. That's all I can say."
In 1987, for Petit, it was the end of the MHD story. He published three papers on theoretical cosmology in Modern Physics Letters A, in '88-'89.
...Since 1977, Petit had been very interested in Sakharov's ideas (twin universe model). He published two papers in the French Comptes rendus de l'Académie des Sciences this year. Ten years after the MHD parenthesis was indefinitely closed, he was back on the subject.
...He published a new paper in Nuovo Cimento in 1994, entitled "The Missing Mass Problem" (reproduced in Geometrical Physics A, 1). Another one in Astrophysics and Space Science, 1995 (reproduced in Geometrical Physics A, 2). Then the troubles started. Many papers, sent to several journals, were returned without submission to a referee, with short sentences like:
"Sorry, we don't publish speculative works."
...In February 1997, at last, an answer from Astronomy and Astrophysics. The referee answered, "I think the paper is provocative and interesting," and asked a dozen different questions.
...The game began and continued for ten months. The questions were relevant but enlarged the papers a lot. The initial paper had 22 pages. As new questions arrived, the paper grew more and more, finally up to 90 pages.
...The referee asked for a complete cosmological model and asked... sixty questions. Petit wrote seven successive versions. The epistolary exchanges with this anonymous expert were always cordial. Petit thanked the referee for his relevant questions, and the referee thanked him for his patience.
As the paper was now too large, Petit suggested cutting it into two parts. Then suddenly, in December 1997, the Director of the Journal, James Lequeux, wrote to Petit:
"That's enough now. This will never end. I'm stopping it. That's my decision, and it's final."
...No warning, no incitement to finish the job, nothing. Just this abrupt and unexpected decision.
...Petit asked for a chance to get some pages published in Astronomy and Astrophysics and suggested submitting a shortened version to the referee, composed of that which the man had approved along the long correspondence. Lequeux refused.
...Petit asked Dr. Lequeux to transmit a last letter to his referee, in which he asked:
"Do you confirm the rejection decision of the Director of Astronomy and Astrophysics? If yes, could you send me your final scientific arguments?"
...No answer has been received since January 12, 1998. In a last letter (26/03/98), Dr. Lequeux wrote to Petit (see the Log Book):
"I recall that the Director of the Journal is the only one who decides if a paper is or is not suitable for publication and that the referee's report is only consultative."
End of story.
The website created by Petit has several aims:
- To submit past and new works to scientists in order to receive their eventual opinions and remarks, if they have any to formulate. They will be reproduced. If they are relevant, the papers will eventually be modified. If they are not, the author will try to explain why.
- To diffuse some knowledge about group theory, geometry, and other different topics.
- To inform people.
Since September 3, 2005, number of connections: