sunnuntai, 27. elokuu 2017

Donald Trumpin setä fysiikan professori John G. Trump oli "tutkateknologian Oppenheimer" II maailmansodassa

Teoreettinen fyysikko, professori Julius Robert Oppenheimer (1904-1967) oli atomi-pommin kehityksen loppuunsaattaneen Manhattan-projektin (9.10.1941-1.12. 1946) amerikkalainen johtaja. Hän oli myös varmaan ensimmäinen henkilö, joka konkreetti- sella tasolla aloitti fissiopommin suunnittelun vuonna 1938 jo ennen kuin uraaniato- mia oli laboratoriossa halkaistukaan (joulukuu 1938 Otto Hahn,Otto Frisch, Lise Meit- ner). Viimeistään tuolloin,kun Manhattan-projekti alkoi,USA ja Englanti olivat tehneet yhdessä päätöksen USA:n liittymisestä sotaan, vaikka Ja-panin hyökkäys Pearl Har-boriin tapahtuikin vasta 6.12.1941,samaan aikaan kun Saksa otti takkiinsa Moskovan ratkaisutaistelussa.

Tutkan historia alkaa samalla kun koko radiotekniikan historiakin saksalaisen fyysi-kon Heinrich Hertzin osoittaessa vuonna 1888 näkymättömien sähkömagneettisten aaltojen heijastuvan samoin kuin valo. [29] Tutkatekniikka on aina kehittynyt radiotek-niikan ohessa sen osa-alueena.Sota-aikana tutkimus ja kehitys kiihtyivät, ja tutka vai-kutti suuresti toisen maailmansodan lopputulokseen.Ensimmäisen varsinaisen tutkan rakensi saksalainen Christian Hülsmeyer, joka kehitti telemobiloskoopiksi kutsutun laitteen 1900-luvun alussa. [30] Englannissa vuonna 1942 Robert Watson-Watt aate-loitiin hänen tutkan hyväksi tekemänsä työn vuoksi. Yhdessä  Arnold F. Wilkinsin kanssa hän selvitti,kuinka radioaalloista lentokoneen runkoon indusoituneet virrat sä- teilevät. Tutkimus johti päätelmään, että radioaaltojen avulla voitaisiin havaita ilma-a- luksia. Nykyaikaisen tutkan kehityksen katsotaan usein alkaneen tästä tutkimuksesta. [31]

Tutka ei siis ole mikään kaikuluotain, eivätkä kaikki tutkankin käyttämien mikroaalto-jen lähettämiset ja vastaanottamiset (joissa havaitaan esimerkiksi lähettäjä) tarkoita, että olisi tutka.II maailmansodan alkaessa Englanti oli ainoa maa maailmassa,jolla oli kattava tutkavalvontajärjestelmä. Saksalla oli tuhansia pieniä liikuteltavia tutka-ase-mia (GEMA).Ranskassa oli ainakin laivastolla tutka-asemia. Saksan lähestyessä Pa- riisia 1940 sikäläisen tutkateknologian kehittäjä Maurice Ponte pakeni laitteet muka-naan Englantiin, ja tällä tietämyksellä oli tiettävästi suuri vaikutus tutkan kehitykseen. Neuvostoliitossa oli paikallisia järjestelmiä tärkeiden kohteiden ympärillä,mutta tutkijat riitelivät ja kehitys takkusi. Mm. yksi tärkeä kehittäjä joutui GULAGiin.

Terävimmästä englantilaisesta tutkimuskärjestä ja joistakuista muista muodostettiin "Manhattanin" esimerkin mukaisesti ydinryhmä Britain's  Telecommunications Re-search Establishment (TRE) at  Malvern, in Worcestershire. Sen johtoon tuli vuoden 1944 alusta vuoden 1945 loppuun  John G.Trump, joka oli koko ajan ollut keskeisesti mukana amerikkalaisten puolella.Tehtävä oli äärimmäisen keskeinen,vastuunalainen ja vaativa.Siinä olisi tyrimällä voinut aiheuttaa vielä miljoonien turhan kuoleman. Ryh-mä kehitti myös laivastotutkaa,tarkkuuspommitustutkaa ja saksalaisten tutkien torjun- taa USA:n Ilmavoimien komentajan kenraali  Carl Spaatzin alaisena. Sen tehtäviin kuului myös saksalaisen tutkajärjestelmän haltuunottaminen mieluiten kehittelijöi-neen. Siinä varmaan yksi syy valita saksalaissyntyinen (mutta ehdottoman lutettava!) johtaja.

Näin luotiin nimenomaan USA:n/NATO:n tutkajärjestelmien perusta. Trump ei keksi-nyt tutkaa, kuten ei Oppenheimerkaan keksinyt atomipommia, tai kukaan muukaan yksittäinen henkilö. Sellaisten teoria on sitten toinen juttu. Kun isompi sauhu oli las-keutunut vuonna 1946, J. G. Trump palasi sädehoitolaitebisnesten pariin perustaen entisen esimiehensä  Robert J.Van de Graaffin ja  Denis M. Robinsonin kanssa  High Voltage Engineering Corporation (HVEC)-yhtiön.

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Prof. Emeritus John Trump, c. 1979.
 
JOHN TRUMP DIES; ENGINEER WAS 78

Dr. John G. Trump, a retired teacher and engineer, died Thursday at his home in Cambridge, Mass., after a long illness. He was 78 years old.

Dr.Trump began studying the voltage-insulation properties of high vacuum and com-pressed gases while a faculty member at the Massachusetts Institute of Technology. Working with Prof.  Robert J.van de Graaff, he designed one of the first millionvolt X- ray generators. Used initially for clinical purposes at the Collis P. Huntington Memo-rial Hospital in Boston in 1937, it was a development that provided additional years of life to cancer patients throughout the world.

In 1946, Dr.Trump, along with Dr. Van de Graaff and Dr. Denis M. Robinson, foun-ded the High Voltage Engineering Corporation, which developed the Van de Graaff electrostatic generator.

In World War II Dr. Trump was influential in the development of  radar and short-wave radar equipment. He was appointed director of the British branch of the M.I.T. Radiation Lab in 1944.

After the war Dr.Trump,while still on the faculty at M.I.T.,became associated with the Department of Radiology at the Lahey Clinic in Boston and later became chairman of its board.Under his direction rotational radiation therapy was developed,''an idea that created quite a stir in those days",he recalled later.He also conceived and developed the use of high-energy electrons in the treatment of superficial skin lesions.

He Received Emeritus Status. He became professor emeritus at M.I.T. in 1973, remaining on as a senior lecturer.

He was the author of nearly 80 scientific publications and the recipient of many awards, including His Majesty's Medal, given by George VI in 1947; the Presi-dent's Certificate of Merit,presented by President Truman in 1948; and the Lamme Medal, awarded in 1960 by the American Institute of Electrical Engineers. In 1983, he was the recipent of the National Medal of Science.

He was a graduate of the Polytechnic Institute in 1929,received a master's degree in physics from Columbia University in 1931 and a doctorate from M.I.T. in 1933.

Dr. Trump is survived by three children, John Gordon Trump of Watertown, Mass., Christine Philp of Pittsfield, Mass., and Karen Ingraham of Los Alamos, N. M.; and six grandchildren. He was the brother of Frederick C. Trump and the uncle of Donald Trump, New York real estate developers.

A funeral service will be held Sunday at 2:30 P.M. at the  Unitarian Church in Winchester, Mass.

Donald Trump on useinkin esiintynyt tavalla, joka kertoisi, että huolimatta isältään perimistään bisneksistä setä John oli hänelle korkein ihanne ja suurin auktoriteetti. Eipä hän uskonut eikä totellut isää uskonasioissakaan (vaan piti tätä jopa tyhmänä ainakin siinä suhteessa...).

***

Tässä muistelee yksi John G. Trumpin alainen:

https://www.amazon.com/Alvarez-Adventures-Physicist-Luis-W-ebook/dp/B075TJ1VFK/ref=sr_1_1

Alvarez: Adventures of a Physicist Kindle Edition

by Luis W. Alvarez

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During World War II, Luis W. Alvarez participated in the Allies’ development of radar at the MIT Radiation Laboratory, and of the atomic bomb at Los Alamos. He then worked as an experimental physicist on cyclotrons, particle accelerators and bubble chambers at UC-Berkeley with Ernest Lawrence. Later in life, he used cosmic rays to “X ray” an Egyptian pyramid,developed a new theory about the extinction of the di-nosaurs, and won the 1968 Nobel prize in physics for his work on elementary par-ticles. In this autobiography, Alvarez shares insights on the process of scientific dis-covery, risk-taking in science and how theoretical and experimental physics interact.

“[A] delightful autobiography... [A] fascinating book... It should be read by everyone who is interested in science and adventure, or who just wants to meet one of our most fascinating contemporaries.” — James Trefil, New York Times Book Review

“Beyond its self-portrait, Alvarez provides an exceptionally clear view of the world of science.” — Alan Lightman, Washington Post Book World

“This is a richly absorbing autobiography... Personally as well as scientifically forthright and plainspoken, [Alvarez] holds the reader with the story of his life as a scientist, much of the time at Berkeley, Calif., working with such men as Robert Oppenheimer, Ernest Lawrence and Enrico Fermi.” — Publishers Weekly

“A gripping book. It succeeds well in making the scientific experience and the excite-ment of discovery accessible to the general reader.” — Richard L. Garwin, Physics Today

“A fascinating life.” — Elena Brunet, Los Angeles Times

“One of the best popular books on science to emerge from the laboratory in years.” — Henry Kisor, Chicago Sun-Times

“Luis W. Alvarez has an unsurpassed reputation among scientists for a lifelong record of crucial participation in important discoveries in pure and applied science. In this book he performs an additional service by revealing his thought processes.” — Philip Abelson, Science Advisor, American Association for the Advancement of Science

https://www.reddit.com/r/slatestarcodex/comments/dbd8fm/intellectual_phase_lock/

Intellectual Phase Lock

I'm reading the memoirs of Luis Alvarez (US experimental physicist, Nobel laureate in 1968) and I think this story, from Ch.1, is worth highlighting. I found it very striking:

It really is difficult to make precise measurements. Everyone who has examined the way the best values of the fundamental physical constants have varied with time has noted that there is usually a “fashionable” value that is often many stan-dard deviations away from a later value more precisely known. This phenomenon, which I call intellectual phase lock, occurs partly because no one likes to stand alone.

The person I know who most successfully avoided intellectual phase lock was Frank Dunnington, who worked with Ernest Lawrence at Berkeley in the 1930s. Dunnington spent several years measuring the electron’s charge-to-mass ratio, e/m. He used a method that Lawrence had suggested shortly after he invented the cyclotron, his wonderful instrument for accelerating particles by spiraling them through a magnetic field:the method involves measuring the time it takes an elect-ron to move through some measured fraction of one revolution in a magnetic field,a measurement from which the value of e/m can be calculated.The measure- ment was potentially much more accurate than earlier measurements using different techniques.

Dunnington knew that his e/m results were eagerly awaited but recognized his human susceptibility to intellectual phase lock. If he was going to spend four years of his life on a measurement, then he had to devise a scheme to avoid tilting the answer to an anticipated value.

He did so by deliberately obscuring a crucial piece of information, the angle bet-ween the slits in his experimental arrangement through which the electrons en-tered and exited. He told the head machinist that he wanted the angle somewhere between eighteen and twenty-two degrees,its precise value unknown. The machi- nist complied, and Dunnington began his years of careful measurements and the elimination of all “systematic errors.” Only at the end, after he hadwritten the final draft of his lengthy paper, did he dismantle his apparatus, remove the key slit sys-tem from its vacuum chamber, and mount it on a machine for measuring angles. After a long series of careful measurements, he wrote down the best measured value of the angle, punched that value into his desk calculator, and multiplied it by the number that represented the sum total of his several years of work. The num-ber that appeared in the window of the calculating machine, now the world’s best value of e/m,he wrote in the blank space he had left on the last page of his paper. Then he sealed the envelope and mailed it away.

Dunnington’s care to avoid intellectual phase lock illustrates one major difference between scientists and most other people. Most people are concerned that some-one might cheat them; the scientist is even more concerned that he might cheat himself.

A few additional notes:

  1. I was drawn to Alvarez's book through an old post of Steve Hsu. The quotes in that post are well worth your time, IMO.

  2. Several people pointed out to me that in cosmology and particle physics today "blinding" and later "unblinding" your data has become standard or at least very common (which is fantastic). Here's a Nature article from 2015 on blind analysis.

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