Biography of Jean Pierre Petit

Biography of Jean-Pierre Petit
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...At school, he carried out a number of unpublished personal works on a supersonic disk nozzle, as well as on very thin hypersonic flat jets, which were full of paradoxical characteristics.

...In 1961, he was invited to join Princeton University, and for the journey, he boarded the steamer named Mauretania, the one that had been built just before the Titanic, in England. Fortunately, the journey was good and no iceberg was encountered.

...At Princeton, he joined the James Forrestal Center, directed by Professor Bodganoff, 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 take a look around. He ignored the signs indicating "restricted area, access reserved for authorized persons," and discovered a very strange machine, disk-shaped. He decided to inspect it, and got on board.

...When Dr. Bogdanoff returned from his lunch, Petit decided to talk to him about what he had seen. Bodganoff became angry:

" You're crazy! Do you know that it's a top secret machine!"

Petit replied:

"No kidding, it won't work. It's just a ground effect machine, you'll never be able to take off with it."

...The conversation turned sour, and Petit had to leave the university and immediately depart from Princeton. Without a penny, he earned his living in New York by selling drawings in Greenwich Village in order to raise money for his return ticket.

...The steamer he took for his return to France was the "Liberté" of the well-known "French-Line," and this was to be its last trip, as it had been sold to a Japanese company that wanted to transform it into a floating hotel.

...No icebergs were seen during the return trip, only an autumn storm with a 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 was comparable to the length of the ship, approaching 300 meters. Like the wind, the waves came from behind and one side. The ship, which had been navigated at a roughly constant speed, suddenly started to oscillate. Petit remembers:

• On each rise and fall, the ship tilted at 43°. Two people died on board. An old lady fell in her cabin and hit her basin, and a steward who didn't know how 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 a higher deck of the ship.

...The captain decided to turn west 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 up close. The mountains of black water and foam blocked the horizon. Suddenly, Petit realized that one of the waves flooded the ship's bridge, which became flooded with water, and he himself risked being swept away by a wave, 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 performed 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 profession in 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 became bored and joined a public research institute. He worked on an MHD power plant, a short-duration system based on a so-called "shock tube" (short-duration shock-driven wind tunnel). The latter produced 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, one gets a strong induced electric field VB, and an electric current flowing through wall electrodes and external loads. At such high temperatures, the electric conductivity of argon is high enough to produce 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 efficiency of MHD power plants (theoretically: up to 60%). Laboratories were rich in all countries and spent money.

...MHD experts dreamed of being able to couple their generators to high-temperature reactors (HTR). Inert gases such as argon or helium would cool the reactor core and extract thermal energy from it. Adding 2% cesium would increase the electrical conductivity.

...HTR experts refused to think about reactors operating at temperatures above 1500°C. MHD required 2000 or 2500...

...Then people thought about a two-temperature system (in the US: Kerrebock, in Russia: Shendlin and his collaborators). The idea is simple. A fluorescent tube is a two-temperature device. The gas, argon, is cold. Proof: 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 think that in certain adequate conditions, a two-temperature MHD generator can work, say at a gas temperature of 1500°C and an electron temperature of 2500-3000 Kelvin. You get good electrical conductivity (which depends on electron temperature), good efficiency, in fact, everything is good.

...But in 1964, a young Russian attended an international MHD meeting in Newcastle, UK. The young E. Velikhov, a member of the Russian team. As a theorist, he predicted:

• Your two-temperature plasmas will be quite 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 plant "Typhée" in Fontenay-aux-Roses, concluded: "we are facing the wall of Velikhov's electrothermal instability."

...In 1965, Petit joined the Institute of Fluid Mechanics in Marseille, directed by Professor J. Valensi (deceased since). Copying the American Bert Zauderer, the French used shock tubes to produce at the source a hot gas flow, quickly directed towards small MHD channels. They proved to be relatively low-cost experiments. The two tesla magnetic field was provided by a capacitor bank. The MHD channel was built in plexiglass and the electrodes were made of red copper.

...In France, the French Atomic Energy Commission (CEA, the French department of atomic energy) held almost all the MHD activity in closed cycles. But their huge generator "Typhée," in its large hall, turned out to be unstable like all its brothers around the world. The electric power output was close to zero.

Then the people at the CEA said:

• Why not try to simulate that with these small shock tubes, in the Marseille laboratory?

...The idea came from a young student of Kerrebock: Solbès. In Marseille, the contract was quickly signed, although no one knew what a two-temperature generator was. Recently hired, Petit learned plasma physics. In 1967, Sutton and Sherman had just published their excellent book (Mac Graw 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. Ionization stabilizes the plasma. This phenomenon was rediscovered fifteen years later by a Japanese, who called it "climbing Mount Fuji" (due to the peculiar shape of the instability growth rate curve, resembling 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 high power output, under stable conditions. Gas temperature: 6000°C, electron temperature: 10,000°C. Output power: two megawatts (for 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 vibration energy and radiative output. The process will be very fast, due to the large cross-section of CO2, and I have been able to calculate that.

...Once again, Petit's predictions were correct. He confirmed that he is a good prophet and was able to present his work at the International MHD Meeting in Warsaw in 1967. Later, the gas temperature was successfully lowered to 4000 Kelvin. The plasma stability was confirmed by photos taken with the first available American electronic camera.

...The director of the lab was enthusiastic. Everyone thought that this was the solution, and everyone dreamed of lowering the gas temperature to 1500°C. 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-scale MHD converters.

...The lab's boss decided to run the experiment himself, as usual. He put his own team on the plant built by Petit by his own hands, and rejected him in a small room under the roof. There, Petit calculated again and laughed: the boat is a pierced boat. The theory shows that this method will not allow them to make the gas temperature lower than 4000°C. All that excitement for nothing...

...During the next few months, Petit worked like hell to build his "lifeboat": a Ph.D. thesis based on the kinetic theory of ionized gases. He knew he would have to give up seven years of hard work here, and leave the lab.

...Downstairs, things did not go so well. The boss's collaborators made many mistakes 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 Ph.D. thesis was completed, and he left the lab, which sank. Tired of all that noise, Petit decided to transform electrons into stars, in the equations, and to join the Observatory of Marseille. (Practically, for the specialist: transforming the Boltzmann equation into the Vlasov equation, whose second member is zero).

He has been working there for more than 25 years.

...We have written 30 books. Some have been 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 dressed very scantily, and they exercise their right to make her dress decently, as is customary, with a chador. An Iranian artist takes charge of this operation for her. Iran is not the only country to exercise these changes of clothing of the heroine. The second country was America. When these books were published 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 conference and brought with him the books already printed in England. He offered the books to the library, which made available to the students two types of books, all in English language. 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 microcomputers Apple-II. He wrote the first computer-aided 3D design program (CAO), which worked efficiently on small systems (48K, the 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 Science. He showed that the meridian lines of the mysterious Boy's surface can be ellipses. This will later enable Apery to build the first implicit equation of the surface, sixth degree.

...In 1975, Petit belonged to the Observatory of Marseille. But the old MHD ideas still ran around in his head. In 1965, during the MHD experiments, the slowing down of the plasma in the MHD channel was so strong that a shock wave formed 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 stronger the gas deceleration 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 at the Institute of Fluid Mechanics in Marseille by two researchers: B. Fontaine and B. Forestier. They demonstrated that using the MHD converter as an accelerator, the velocity of the argon plasma (2,750 m/s upon entering the channel) could increase up to 8,000 m/s within a ten-centimeter-long MHD accelerator.

...But at the beginning of the seventies, MHD research ceased in all countries.

...In his observatory, Petit continued pondering the marvelous world of MHD. One day he said:

• If the Lorentz force is strong enough to produce a shock wave when it acts, why couldn't I cancel a shock wave located at the front of a body moving through a gas at supersonic speed—simply by sucking the gas via a suitably designed Lorentz force field? In short, is shockless flight possible at supersonic velocities?

...The idea seemed utterly foolish to conventional fluid mechanics specialists. They said:

• You must have a shock wave system.

...Petit remained unconvinced. When he attended his aeronautical school in Paris, he used a water free surface flow analog simulator. Today, these have completely disappeared from universities and labs. But in the sixties, they were used to simulate shock wave systems—for example, around a flat wing:

...If some readers are interested, further information about MHD topics and shock wave cancellation may be found on this website.

...In short, in 1976, Petit calculated the parameters of an MHD experiment, used a one-tesla magnetic field, water with hydrochloric acid, free surface flow, electrodes, and successfully canceled the water wave in front of a one-centimeter model.

...Later, he supervised a PhD thesis in this field, that of Bertrand Lebrun.

...For fluid mechanics specialists, shock waves occur because "Mach lines focus":

...Where Mach lines accumulate, shock waves tend to grow. But the Lorentz force alters the local Mach angle and the local Mach line system. With his student Bertrand Lebrun, Petit showed in 1982 that, through a properly designed Lorentz force field, the self-intersection of Mach lines could be avoided, thus preventing shock formation.

...Furthermore, all this could be experimentally tested using a transverse magnetic field and wall electrodes. Petit and Lebrun presented their work at the 7th International Meeting in Tsukuba, Japan, 1987 (but due to lack of funds, they couldn’t attend).

...Lebrun computed the field using a set of old Macintosh computers belonging to colleagues of Petit. Each night, each machine processed a portion of the field; every morning, Lebrun collected the results on 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 using a shock-driven channel, as usual. These old systems were nearly obsolete, but a lab in Rouen, France, still possessed one. Petit convinced the French CNRS (Centre National de la Recherche Scientifique) to support his research, and an MHD program was launched with some financial backing. The idea was simple: the old shock tube generated a short-duration (200 microseconds), hot (10,000 K), dense (1 bar pressure) argon flow. In the first step, a stereoscopic system based on a small laser showed the shock wave system around a flat wing with a sharp edge.

...Then, during another test, MHD would be activated using an appropriate magnetic field (a 2-tesla field supplied by a capacitor bank) and suitable electric discharge in the plasma through wall electrodes (also powered by capacitor discharge). One might then expect that the Lorentz force would cancel the wave, especially the front waves.

Petit:

• I'm certain this would have succeeded on the first test. Everything was carefully calculated...

...But the French Army stopped everything. The military were very 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 state's reasons were a solid reality.

...No one can fight against the Army. He finally gave up and shifted toward theoretical cosmology in 1987.

...In 1987, Petit came to the Department of Fluid Mechanics at Berkeley, whose director—now retired—was his old friend Tonio Oppenheim, who invited him to give a lecture on MHD and shock wave cancellation.

...In the same room sat another colleague named Kunkle, who was the director of particle accelerators at Berkeley University. During Petit's lecture, he laughed constantly. Finally, puzzled by his colleague’s unusual behavior, Oppenheim asked:

• Dear Professor Kunkle, we’ve been friends for many years. Why are you disrupting my friend Petit’s conference?

• Sorry, it’s just too much for me. Petit is explaining, to all these young students, in clear terms, a lot of research currently being conducted at the Lawrence Livermore Laboratory. But there, it’s considered highly classified. In fact, so classified that I’m not authorized to tell you even one word about it. But they are... very similar. That’s all I can say.

In 1987, for Petit, this marked the end of the MHD story. He published three papers on theoretical cosmology in Modern Physics Letters A in 1988–1989.

...Since 1977, Petit had been deeply interested in Sakharov’s ideas (the twin universe model). He published two papers in the French Comptes rendus de l'Académie des Sciences this year. Ten years after the MHD interlude was permanently closed, he returned to 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 troubles began. Many papers sent to various journals were returned without being sent to a referee, accompanied by brief notes such as:

• Sorry, we don’t publish speculative works.

...In February 1997, at last, a response came from Astronomy and Astrophysics. The referee replied: "I think the paper is provocative and interesting," and asked dozens of different questions.

...The game began and continued for ten months. The questions were relevant but greatly expanded the papers. The original paper was 22 pages long. As new questions arrived, the paper kept growing—eventually reaching 90 pages.

...The referee requested a complete cosmological model and posed about sixty questions. Petit wrote seven successive versions. The correspondence with this anonymous expert remained cordial throughout. Petit thanked the referee for his insightful questions, and the referee thanked him for his patience.

Since the paper was now too long, Petit suggested splitting it into two parts. Then suddenly, in December 1997, the Journal’s Editor, 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 encouragement to conclude the work—nothing. Just this abrupt and unexpected decision.

...Petit asked for a chance to publish some pages in Astronomy and Astrophysics, suggesting submitting a shortened version composed of what the referee had approved during their long correspondence. Lequeux refused.

...Petit asked Dr. Lequeux to forward a final letter to his referee, in which he asked:

• Do you confirm the Editor’s rejection decision for Astronomy and Astrophysics? If yes, could you send me your final scientific arguments?

...No answer has been received since January 1998, the twelfth. In a final letter (26/03/98), Dr. Lequeux wrote to Petit (see the Log Book):

• I recall that the Journal’s Editor is the sole person who decides whether a paper is suitable for publication, and that the referee’s report is only advisory.

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 any. These will be reproduced. If relevant, the papers will eventually be revised. If not, the author will attempt to explain why.
• To disseminate knowledge about group theory, geometry, and other related topics.
• To inform people.

Back to homepage

Since September 3, 2005, number of connections: