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Biophysics is an interdisciplinary science that applies approaches and methods traditionally used in physics to study biological phenomena. Biophysics covers all scales of biological organization , from molecular to organismic and populations . Biophysical research shares significant overlap with biochemistry , molecular biology , physical chemistry , physiology , nanotechnology , bioengineering , computational biology , biomechanics , developmental biology and systems biology .

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123-596: The term biophysics was originally introduced by Karl Pearson in 1892. The term biophysics is also regularly used in academia to indicate the study of the physical quantities (e.g. electric current , temperature , stress , entropy ) in biological systems. Other biological sciences also perform research on the biophysical properties of living organisms including molecular biology , cell biology , chemical biology , and biochemistry . Molecular biophysics typically addresses biological questions similar to those in biochemistry and molecular biology , seeking to find

246-683: A Quaker family. His father was William Pearson QC of the Inner Temple , and his mother Fanny (née Smith), and he had two siblings, Arthur and Amy. Pearson attended University College School , followed by King's College, Cambridge , in 1876 to study mathematics, graduating in 1879 as Third Wrangler in the Mathematical Tripos . He then travelled to Germany to study physics at the University of Heidelberg under G. H. Quincke and metaphysics under Kuno Fischer . He next visited

369-424: A "bum". The young Feynman was heavily influenced by his father, who encouraged him to ask questions to challenge orthodox thinking, and who was always ready to teach Feynman something new. From his mother, he gained the sense of humor that he had throughout his life. As a child, he had a talent for engineering, maintained an experimental laboratory in his home, and delighted in repairing radios. This radio repairing

492-427: A branch of biophysics, is any application of physics to medicine or healthcare , ranging from radiology to microscopy and nanomedicine . For example, physicist Richard Feynman theorized about the future of nanomedicine . He wrote about the idea of a medical use for biological machines (see nanomachines ). Feynman and Albert Hibbs suggested that certain repair machines might one day be reduced in size to

615-478: A bunch of professional soldiers," Wilson later recalled, "we signed up, en masse, to go to Los Alamos." Like many other young physicists, Feynman soon fell under the spell of the charismatic Oppenheimer, who telephoned Feynman long distance from Chicago to inform him that he had found a Presbyterian sanatorium in Albuquerque, New Mexico for Arline. They were among the first to depart for New Mexico, leaving on

738-592: A car from his friend Klaus Fuchs to drive to Albuquerque to see Arline. Asked who at Los Alamos was most likely to be a spy, Fuchs mentioned Feynman's safe-cracking and frequent trips to Albuquerque; Fuchs himself later confessed to spying for the Soviet Union . The FBI would compile a bulky file on Feynman, particularly in view of Feynman's Q clearance . Informed that Arline was dying, Feynman drove to Albuquerque and sat with her for hours until she died on June 16, 1945. He then immersed himself in work on

861-570: A father of the Xbox , bought the van. Qantum was the license plate ID. At Caltech, Feynman investigated the physics of the superfluidity of supercooled liquid helium , where helium seems to display a complete lack of viscosity when flowing. Feynman provided a quantum-mechanical explanation for the Soviet physicist Lev Landau 's theory of superfluidity. Applying the Schrödinger equation to

984-492: A high pitch of internal efficiency by insuring that its numbers are substantially recruited from the better stocks, and kept up to a high pitch of external efficiency by contest, chiefly by way of war with inferior races." He reasoned that, if August Weismann 's theory of germ plasm is correct, the nation is wasting money when it tries to improve people who come from poor stock. Weismann argued that acquired characteristics could not be inherited. Therefore, training benefits only

1107-496: A junior physicist, he was not central to the project. He administered the computation group of human computers in the theoretical division. With Stanley Frankel and Nicholas Metropolis , he assisted in establishing a system for using IBM punched cards for computation. He invented a new method of computing logarithms that he later used on the Connection Machine . An avid drummer, Feynman figured out how to get

1230-476: A mechanism for inheritance, but rather on providing a mathematical description for inheritance that was not causal in nature. While Galton proposed a discontinuous theory of evolution, in which species would have to change via large jumps rather than small changes that built up over time, Pearson pointed out flaws in Galton's argument and actually used Galton's ideas to further a continuous theory of evolution, whereas

1353-508: A particular mechanism of genetics was not a worthy pursuit of biologists, who should instead focus on mathematical descriptions of empirical data. This, in part led to the fierce debate between the biometricians and the Mendelians, including Bateson . After Bateson rejected one of Pearson's manuscripts that described a new theory for the variability of an offspring, or homotyposis, Pearson and Weldon established Biometrika in 1902. Although

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1476-687: A point of dating other men, but Feynman proposed in early 1960. They were married on September 24, 1960, at the Huntington Hotel in Pasadena . They had a son, Carl, in 1962, and adopted a daughter, Michelle, in 1968. Besides their home in Altadena, they had a beach house in Baja California , purchased with the money from Feynman's Nobel Prize. Feynman tried marijuana and ketamine at John Lilly 's sensory deprivation tanks , as

1599-414: A relativistic version. Feynman thought that he could do this, but when he went back to Bethe with his solution, it did not converge. Feynman carefully worked through the problem again, applying the path integral formulation that he had used in his thesis. Like Bethe, he made the integral finite by applying a cut-off term. The result corresponded to Bethe's version. Feynman presented his work to his peers at

1722-586: A result our opinions as to moral conduct. Even at the present day there are far too many general impressions drawn from limited or too often wrongly interpreted experience, and far too many inadequately demonstrated and too lightly accepted theories for any nation to proceed hastily with unlimited Eugenic legislation. This statement, however, must never be taken as an excuse for indefinitely suspending all Eugenic teaching and every form of communal action in matters of sex. Nonetheless, in June 2020 UCL announced that it

1845-493: A sense of failure of his aim to use the scientific study of eugenics as a guide for moral conduct and public policy. My endeavour during the twenty-two years in which I have held the post of Galton Professor has been to prove in the first place that Eugenics can be developed as an academic study, and in the second place to make the conclusions drawn from that study a ground for social propagandism only when there are sound scientific reasons upon which to base our judgments and as

1968-630: A statistician himself and succeeded his father as head of the Applied Statistics Department at University College. Maria died in 1928 and in 1929 Karl married Margaret Victoria Child, a co-worker at the Biometric Laboratory. He and his family lived at 7 Well Road in Hampstead , now marked with a blue plaque . He died at Coldharbour, Surrey , on 27 April 1936. When the 23-year-old Albert Einstein started

2091-514: A train on March 28, 1943. The railroad supplied Arline with a wheelchair, and Feynman paid extra for a private room for her. There they spent their wedding anniversary. At Los Alamos, Feynman was assigned to Hans Bethe's Theoretical (T) Division, and impressed Bethe enough to be made a group leader. He and Bethe developed the Bethe–Feynman formula for calculating the yield of a fission bomb , which built upon previous work by Robert Serber . As

2214-657: A way of studying consciousness . He gave up alcohol when he began to show vague, early signs of alcoholism , as he did not want to consume anything that could damage his brain. Despite his curiosity about hallucinations , he was reluctant to experiment with LSD . Feynman had synesthesia , and said that mathematical symbols had different colors for him: "When I see equations, I see the letters in colors. I don't know why. I see vague pictures of Bessel functions with light-tan j's, slightly violet-bluish n's, and dark brown x's flying around." There had been protests over his alleged sexism in 1968, and again in 1972. Although there

2337-408: Is a purely relative conception. An observer who travels at the exact velocity of light would see an eternal now, or an absence of motion. He speculated that an observer who travelled faster than light would see time reversal, similar to a cinema film being run backwards. Pearson also discussed antimatter , the fourth dimension , and wrinkles in time. Pearson's relativity was based on idealism , in

2460-574: Is an example of what is today described as scientific racism . Pearson was a protégé and biographer of Sir Francis Galton . He edited and completed both William Kingdon Clifford 's Common Sense of the Exact Sciences (1885) and Isaac Todhunter 's History of the Theory of Elasticity , Vol. 1 (1886–1893) and Vol. 2 (1893), following their deaths. Pearson was born in Islington , London, into

2583-430: Is becoming increasingly common for biophysicists to apply the models and experimental techniques derived from physics , as well as mathematics and statistics , to larger systems such as tissues , organs , populations and ecosystems . Biophysical models are used extensively in the study of electrical conduction in single neurons , as well as neural circuit analysis in both tissue and whole brain. Medical physics ,

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2706-501: Is credited as a leader of the field's further development in the mid-20th century. He was a leader in developing electrosurgery . The popularity of the field rose when the book What Is Life? by Erwin Schrödinger was published. Since 1957, biophysicists have organized themselves into the Biophysical Society which now has about 9,000 members over the world. Some authors such as Robert Rosen criticize biophysics on

2829-540: Is either a Communist or very strongly pro-Communist—and as such is a very definite security risk. This man is, in my opinion, an extremely complex and dangerous person, a very dangerous person to have in a position of public trust ... In matters of intrigue Richard Feynman is, I believe immensely clever—indeed a genius—and he is, I further believe, completely ruthless, unhampered by morals, ethics, or religion—and will stop at absolutely nothing to achieve his ends. The U.S. government nevertheless sent Feynman to Geneva for

2952-478: Is in the world worth knowing—that not one subject in the universe is unworthy of study? The giants of literature, the mysteries of many-dimensional space, the attempts of Boltzmann and Crookes to penetrate Nature's very laboratory, the Kantian theory of the universe, and the latest discoveries in embryology, with their wonderful tales of the development of life—what an immensity beyond our grasp! [...] Mankind seems on

3075-661: Is known as the Hellmann–Feynman theorem . In 1939, Feynman received a bachelor's degree and was named a Putnam Fellow . He attained a perfect score on the graduate school entrance exams to Princeton University in physics—an unprecedented feat—and an outstanding score in mathematics, but did poorly on the history and English portions. The head of the physics department there, Henry D. Smyth , had another concern, writing to Philip M. Morse to ask: "Is Feynman Jewish? We have no definite rule against Jews but have to keep their proportion in our department reasonably small because of

3198-628: Is no evidence he supported discrimination against women in science, protestors "objected to his use of sexist stories about 'lady drivers' and clueless women in his lectures." Feynman recalled protesters entering a hall and picketing a lecture he was about to make in San Francisco, calling him a "sexist pig". Seeing the protesters, as Feynman later recalled the incident, he addressed institutional sexism by saying that "women do indeed suffer prejudice and discrimination in physics, and your presence here today serves to remind us of these difficulties and

3321-492: Is not to be expected according to Vallarta and Feynman". When they next met, Feynman asked gleefully whether Vallarta had seen Heisenberg's book. Vallarta knew why Feynman was grinning. "Yes," he replied. "You're the last word in cosmic rays." The other was his senior thesis, on "Forces in Molecules", based on a topic assigned by John C. Slater , who was sufficiently impressed by the paper to have it published. Its main result

3444-531: Is to leave them to fight it out among themselves, and even then the struggle for existence between individual and individual, between tribe and tribe, may not be supported by that physical selection due to a particular climate on which probably so much of the Aryan's success depended. In The Myth of the Jewish Race Raphael and Jennifer Patai cite Karl Pearson's 1925 opposition (in the first issue of

3567-485: The frigideira , a metal percussion instrument based on a frying pan. He was an enthusiastic amateur player of bongo and conga drums and often played them in the pit orchestra in musicals. He spent time in Rio with his friend Bohm, but Bohm could not convince Feynman to investigate Bohm's ideas on physics. Feynman did not return to Cornell. Bacher, who had been instrumental in bringing Feynman to Cornell, had lured him to

3690-561: The Drapers' Company Research Memoirs largely to provide a record of the output of the Department of Applied Statistics not published elsewhere. Pearson's thinking underpins many of the 'classical' statistical methods which are in common use today. Examples of his contributions are: Pearson achieved widespread recognition across a range of disciplines and his membership of, and awards from, various professional bodies reflects this: He

3813-519: The Physical Review . One of these, which was co-written with Manuel Vallarta , was entitled "The Scattering of Cosmic Rays by the Stars of a Galaxy". Vallarta let his student in on a secret of mentor-protégé publishing: the senior scientist's name comes first. Feynman had his revenge a few years later, when Heisenberg concluded an entire book on cosmic rays with the phrase: "such an effect

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3936-591: The Arista Honor Society , in his last year in high school he won the New York University Math Championship. His habit of direct characterization sometimes rattled more conventional thinkers; for example, one of his questions, when learning feline anatomy , was "Do you have a map of the cat?" (referring to an anatomical chart). Feynman applied to Columbia University but was not accepted because of its quota for

4059-651: The Galton Chair of Genetics —in accordance with Galton's wishes. Pearson formed the Department of Applied Statistics (with financial support from the Drapers' Company ), which combined the Biometric and Galton Laboratories . He remained with the department until his retirement in 1933, and continued to work until his death. In 1890, Pearson married Maria Sharpe. The couple had three children: Sigrid Loetitia Pearson, Helga Sharpe Pearson, and Egon Pearson , who became

4182-530: The Karl Pearson page at the Department of Statistical Sciences at University College London, which has been placed in the public domain. The main source for that page was A list of the papers and correspondence of Karl Pearson (1857–1936) held in the Manuscripts Room, University College London Library, compiled by M. Merrington, B. Blundell, S. Burrough, J. Golden and J. Hogarth and published by

4305-507: The Olympia Academy study group in 1902, with his two younger friends, Maurice Solovine and Conrad Habicht, his first reading suggestion was Pearson's The Grammar of Science . This book covered several themes that were later to become part of the theories of Einstein and other scientists. Pearson asserted that the laws of nature are relative to the perceptive ability of the observer. Irreversibility of natural processes, he argued,

4428-541: The Pocono Conference in 1948. It did not go well. Julian Schwinger gave a long presentation of his work in quantum electrodynamics, and Feynman then offered his version, entitled "Alternative Formulation of Quantum Electrodynamics". The unfamiliar Feynman diagrams , used for the first time, puzzled the audience. Feynman failed to get his point across, and Paul Dirac , Edward Teller and Niels Bohr all raised objections. To Freeman Dyson , one thing at least

4551-613: The University of Berlin , where he attended the lectures of the physiologist Emil du Bois-Reymond on Darwinism (Emil was a brother of Paul du Bois-Reymond , the mathematician). Pearson also studied Roman Law, taught by Bruns and Mommsen , medieval and 16th century German Literature, and Socialism. He became an accomplished historian and Germanist and spent much of the 1880s in Berlin , Heidelberg , Vienna , Saig bei Lenzkirch , and Brixlegg . He wrote on Passion plays , religion, Goethe , Werther , as well as sex-related themes, and

4674-598: The University of Wisconsin–Madison as an assistant professor of physics, but was on unpaid leave during his involvement in the Manhattan Project. In 1945, he received a letter from Dean Mark Ingraham of the College of Letters and Science requesting his return to the university to teach in the coming academic year. His appointment was not extended when he did not commit to returning. In a talk given there several years later, Feynman quipped, "It's great to be back at

4797-527: The ferry to Staten Island , where they were married in the city office. The ceremony was attended by neither family nor friends and was witnessed by a pair of strangers. Feynman could kiss Arline only on the cheek. After the ceremony he took her to Deborah Hospital , where he visited her on weekends. In 1941, with World War II occurring in Europe but the United States not yet at war, Feynman spent

4920-523: The gene as the mechanism for inheritance. Pearson criticized Bateson and other biologists for their failure to adopt biometrical techniques in their study of evolution. Pearson criticized biologists who did not focus on the statistical validity of their theories, stating that "before we can accept [any cause of a progressive change] as a factor we must have not only shown its plausibility but if possible have demonstrated its quantitative ability" Biologists had succumb to "almost metaphysical speculation as to

5043-579: The principle of stationary action to problems of quantum mechanics, inspired by a desire to quantize the Wheeler–Feynman absorber theory of electrodynamics, and laid the groundwork for the path integral formulation and Feynman diagrams. A key insight was that positrons behaved like electrons moving backwards in time. James Gleick wrote: This was Richard Feynman nearing the crest of his powers. At twenty-three ... there may now have been no physicist on earth who could match his exuberant command over

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5166-431: The synagogue every Friday. However, by his youth, Feynman described himself as an "avowed atheist ". Many years later, in a letter to Tina Levitan , declining a request for information for her book on Jewish Nobel Prize winners, he stated, "To select, for approbation the peculiar elements that come from some supposedly Jewish heredity is to open the door to all kinds of nonsense on racial theory", adding, "at thirteen I

5289-591: The "Mathematical Formulation of the Quantum Theory of Electromagnetic Interaction" in 1950 and "An Operator Calculus Having Applications in Quantum Electrodynamics" in 1951, he developed the mathematical basis of his ideas, derived familiar formulae and advanced new ones. While papers by others initially cited Schwinger, papers citing Feynman and employing Feynman diagrams appeared in 1950, and soon became prevalent. Students learned and used

5412-400: The 1954 Oppenheimer security hearing ("Where there's smoke there's fire") offended him. They separated on May 20, 1956. An interlocutory decree of divorce was entered on June 19, 1956, on the grounds of "extreme cruelty". The divorce became final on May 5, 1958. He begins working calculus problems in his head as soon as he awakens. He did calculus while driving in his car, while sitting in

5535-588: The California Institute of Technology (Caltech). Part of the deal was that he could spend his first year on sabbatical in Brazil. He had become smitten by Mary Louise Bell from Neodesha, Kansas . They had met in a cafeteria in Cornell, where she had studied the history of Mexican art and textiles. She later followed him to Caltech, where he gave a lecture. While he was in Brazil, she taught classes on

5658-531: The Exact Sciences (1885) when William Kingdon Clifford died. 1891 saw him also appointed to the professorship of Geometry at Gresham College ; here he met Walter Frank Raphael Weldon , a zoologist who had some interesting problems requiring quantitative solutions. The collaboration, in biometry and evolutionary theory, was a fruitful one and lasted until Weldon died in 1906. Weldon introduced Pearson to Charles Darwin 's cousin Francis Galton , who

5781-482: The Mendelians favored a discontinuous theory of evolution. While Galton focused primarily on the application of statistical methods to the study of heredity, Pearson and his colleague Weldon expanded statistical reasoning to the fields of inheritance, variation, correlation, and natural and sexual selection. For Pearson, the theory of evolution was not intended to identify a biological mechanism that explained patterns of inheritance, whereas Mendelian's theory postulated

5904-682: The Publications Office, University College London, 1983. Additional information from entry for Karl Pearson in the Sackler Digital Archive of the Royal Society Richard Feynman Richard Phillips Feynman ( / ˈ f aɪ n m ə n / ; May 11, 1918 – February 15, 1988) was an American theoretical physicist . He is best known for his work in the path integral formulation of quantum mechanics ,

6027-619: The September 1958 Atoms for Peace Conference. On the beach at Lake Geneva , he met Gweneth Howarth, who was from Ripponden , West Yorkshire, and working in Switzerland as an au pair . Feynman's love life had been turbulent since his divorce; his previous girlfriend had walked off with his Albert Einstein Award medal and, on the advice of an earlier girlfriend, had feigned pregnancy and extorted him into paying for an abortion, then used

6150-515: The Talmud had evolved, and everything that was discussed was carefully recorded. Despite being impressed, Feynman was disappointed with the lack of interest for nature and the outside world expressed by the rabbis, who cared about only those questions which arise from the Talmud. Feynman attended Far Rockaway High School , which was also attended by fellow Nobel laureates Burton Richter and Baruch Samuel Blumberg . Upon starting high school, Feynman

6273-653: The University of California, but the head of the physics department, Raymond T. Birge , was reluctant. He made Feynman an offer in May 1945, but Feynman turned it down. Cornell matched its salary offer of $ 3,900 (equivalent to $ 66,000 in 2023) per annum. Feynman became one of the first of the Los Alamos Laboratory's group leaders to depart, leaving for Ithaca, New York , in October 1945. Because Feynman

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6396-578: The base of natural logarithms , e = 2.71828 ...), and found that the three filing cabinets where a colleague kept research notes all had the same combination. He left notes in the cabinets as a prank, spooking his colleague, Frederic de Hoffmann , into thinking a spy had gained access to them. Feynman's $ 380 (equivalent to $ 7,000 in 2023) monthly salary was about half the amount needed for his modest living expenses and Arline's medical bills, and they were forced to dip into her $ 3,300 (equivalent to $ 58,000 in 2023) in savings. On weekends he borrowed

6519-540: The biography Genius: The Life and Science of Richard Feynman by James Gleick . Feynman was born on May 11, 1918, in New York City, to Lucille ( née  Phillips ; 1895–1981), a homemaker , and Melville Arthur Feynman (1890–1946), a sales manager. Feynman's father was born into a Jewish family in Minsk , Russian Empire , and immigrated with his parents to the United States at the age of five. Feynman's mother

6642-520: The biometric approach to inheritance eventually lost to the Mendelian approach, the techniques Pearson and the biometricians at the time developed are vital to studies of biology and evolution today. Pearson's work was all-embracing in the wide application and development of mathematical statistics, and encompassed the fields of biology , epidemiology , anthropometry, medicine, psychology and social history. In 1901, with Weldon and Galton, he founded

6765-489: The cafeteria at Cornell when someone tossed a dinner plate in the air. He read the work of Sir William Rowan Hamilton on quaternions , and tried unsuccessfully to use them to formulate a relativistic theory of electrons. His work during this period, which used equations of rotation to express various spinning speeds, ultimately proved important to his Nobel Prize–winning work, yet because he felt burned out and had turned his attention to less immediately practical problems, he

6888-623: The calutron, but Feynman and Paul Olum struggled to determine whether it was practical. Ultimately, on Lawrence's recommendation, the isotron project was abandoned. At this juncture, in early 1943, Robert Oppenheimer was establishing the Los Alamos Laboratory , a secret laboratory on a mesa in New Mexico where atomic bombs would be designed and built. An offer was made to the Princeton team to be redeployed there. "Like

7011-402: The causes of heredity," which had replaced the process of experimental data collection that actually might allow scientists to narrow down potential theories. For Pearson, laws of nature were useful for making accurate predictions and for concisely describing trends in observed data. Causation was the experience "that a certain sequence has occurred and recurred in the past". Thus, identifying

7134-426: The conditions of Feynman's scholarship to Princeton was that he could not be married; nevertheless, he continued to see his high school sweetheart, Arline Greenbaum, and was determined to marry her once he had been awarded his PhD despite the knowledge that she was seriously ill with tuberculosis . This was an incurable disease at the time, and she was not expected to live more than two years. On June 29, 1942, they took

7257-471: The difficulty of placing them." Morse conceded that Feynman was indeed Jewish, but reassured Smyth that Feynman's "physiognomy and manner, however, show no trace of this characteristic". Attendees at Feynman's first seminar, which was on the classical version of the Wheeler–Feynman absorber theory , included Albert Einstein , Wolfgang Pauli , and John von Neumann . Pauli made the prescient comment that

7380-591: The engineering shops, but drew up the schedule in Mittel- and Althochdeutsch for the Medieval Languages Tripos. In his first book, The New Werther , Pearson gives a clear indication of why he studied so many diverse subjects: I rush from science to philosophy, and from philosophy to our old friends the poets; and then, over-wearied by too much idealism, I fancy I become practical in returning to science. Have you ever attempted to conceive all there

7503-414: The engineers there in devising safety procedures for material storage so that criticality accidents could be avoided, especially when enriched uranium came into contact with water, which acted as a neutron moderator . He insisted on giving the rank and file a lecture on nuclear physics so that they would realize the dangers. He explained that while any amount of unenriched uranium could be safely stored,

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7626-401: The enriched uranium had to be carefully handled. He developed a series of safety recommendations for the various grades of enrichments. He was told that if the people at Oak Ridge gave him any difficulty with his proposals, he was to inform them that Los Alamos "could not be responsible for their safety otherwise". Returning to Los Alamos, Feynman was put in charge of the group responsible for

7749-442: The founder of the biometrical school for inheritance. In fact, Pearson devoted much time during 1893 to 1904 to developing statistical techniques for biometry. These techniques, which are widely used today for statistical analysis, include the chi-squared test , standard deviation , and correlation and regression coefficients. Pearson's Law of Ancestral Heredity stated that germ plasm consisted of heritable elements inherited from

7872-532: The ground that the biophysical method does not take into account the specificity of biological phenomena. While some colleges and universities have dedicated departments of biophysics, usually at the graduate level, many do not have university-level biophysics departments, instead having groups in related departments such as biochemistry , cell biology , chemistry , computer science , engineering , mathematics , medicine , molecular biology , neuroscience , pharmacology , physics , and physiology . Depending on

7995-408: The groundwork for the path integral formulation and Feynman diagrams. With Murray Gell-Mann , Feynman developed a model of weak decay , which showed that the current coupling in the process is a combination of vector and axial currents (an example of weak decay is the decay of a neutron into an electron, a proton, and an antineutrino ). Although E. C. George Sudarshan and Robert Marshak developed

8118-473: The history of furniture and interiors at Michigan State University . He proposed to her by mail from Rio de Janeiro, and they married in Boise, Idaho , on June 28, 1952, shortly after he returned. They frequently quarreled and she was frightened by what she decided was "a violent temper". Their politics were different; although he registered and voted as a Republican , she was more conservative, and her opinion on

8241-675: The house's convenience and said that "it's there that I did the fundamental work" for which he won the Nobel Prize. Feynman spent several weeks in Rio de Janeiro in July 1949. That year, the Soviet Union detonated its first atomic bomb , generating concerns about espionage. Fuchs was arrested as a Soviet spy in 1950 and the FBI questioned Bethe about Feynman's loyalty. Physicist David Bohm

8364-410: The journal Biometrika whose object was the development of statistical theory. He edited this journal until his death. Among those who assisted Pearson in his research were a number of female mathematicians who included Beatrice Mabel Cave-Browne-Cave , Frances Cave-Browne-Cave , and Alice Lee . He also founded the journal Annals of Eugenics (now Annals of Human Genetics ) in 1925. He published

8487-465: The journal Annals of Eugenics which he founded) to Jewish immigration into Britain. Pearson alleged that these immigrants "will develop into a parasitic race. [...] Taken on the average , and regarding both sexes, this alien Jewish population is somewhat inferior physically and mentally to the native population". Pearson concluding remarks on stepping down as editor of the Annals of Eugenics , indicate

8610-524: The living room, and while lying in bed at night. In the wake of the 1957 Sputnik crisis , the U.S. government's interest in science rose for a time. Feynman was considered for a seat on the President's Science Advisory Committee , but was not appointed. At this time, the FBI interviewed a woman close to Feynman, possibly his ex-wife Bell, who sent a written statement to J. Edgar Hoover on August 8, 1958: I do not know—but I believe that Richard Feynman

8733-613: The machine to click in musical rhythms. Other work at Los Alamos included calculating neutron equations for the Los Alamos "Water Boiler", a small nuclear reactor , to measure how close an assembly of fissile material was to criticality. On completing this work, Feynman was sent to the Clinton Engineer Works in Oak Ridge, Tennessee , where the Manhattan Project had its uranium enrichment facilities. He aided

8856-510: The mathematical expressions describing the behavior of subatomic particles , which later became known as Feynman diagrams . During his lifetime, Feynman became one of the best-known scientists in the world. In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World , he was ranked the seventh-greatest physicist of all time. He assisted in the development of the atomic bomb during World War II and became known to

8979-576: The money to buy furniture. When Feynman found that Howarth was being paid only $ 25 a month, he offered her $ 20 (equivalent to $ 202 in 2022) a week to be his live-in maid. Feynman knew that this sort of behavior was illegal under the Mann Act , so he had a friend, Matthew Sands , act as her sponsor. Howarth pointed out that she already had two boyfriends, but decided to take Feynman up on his offer, and arrived in Altadena, California , in June 1959. She made

9102-760: The nanoscale. Molecular biophysicists often consider complex biological events as systems of interacting entities which can be understood e.g. through statistical mechanics , thermodynamics and chemical kinetics . By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are often able to directly observe, model or even manipulate the structures and interactions of individual molecules or complexes of molecules. In addition to traditional (i.e. molecular and cellular) biophysical topics like structural biology or enzyme kinetics , modern biophysics encompasses an extraordinarily broad range of research, from bioelectronics to quantum biology involving both experimental and theoretical tools. It

9225-418: The native materials of theoretical science. It was not just a facility at mathematics (though it had become clear ... that the mathematical machinery emerging in the Wheeler–Feynman collaboration was beyond Wheeler's own ability). Feynman seemed to possess a frightening ease with the substance behind the equations, like Einstein at the same age, like the Soviet physicist Lev Landau —but few others. One of

9348-480: The need to remedy them". In 1975, in Long Beach, CA , Feynman bought a Dodge Tradesman Maxivan with a bronze-khaki exterior and yellow-green interior, with custom Feynman diagram exterior murals. After Feynman's death, Gweneth sold the van for $ 1 to one of Feynman's friends, film producer Ralph Leighton, who later put it into storage, where it began to rust. In 2012, video game designer Seamus Blackley ,

9471-492: The needs of publishers or to the tastes of the reading public", triumphed Galton's life, work and personal heredity. He predicted that Galton, rather than Charles Darwin , would be remembered as the most prodigious grandson of Erasmus Darwin . When Galton died, he left the residue of his estate to the University of London for a chair in Eugenics. Pearson was the first holder of this chair—the Galton Chair of Eugenics , later

9594-583: The number of Jews admitted . Instead, he attended the Massachusetts Institute of Technology , where he joined the Pi Lambda Phi fraternity. Although he originally majored in mathematics, he later switched to electrical engineering, as he considered mathematics to be too abstract. Noticing that he "had gone too far", he then switched to physics, which he claimed was "somewhere in between". As an undergraduate, he published two papers in

9717-533: The offer of being created an OBE ( Officer of the Order of the British Empire ) in 1920 and also to refuse a knighthood in 1935. A eugenicist who applied social Darwinism to entire nations, Pearson saw war against "inferior races" as a logical implication of the theory of evolution. "My view – and I think it may be called the scientific view of a nation", he wrote, "is that of an organized whole, kept up to

9840-529: The only university that ever had the good sense to fire me." As early as October 30, 1943, Bethe had written to the chairman of the physics department of his university, Cornell , to recommend that Feynman be hired. On February 28, 1944, this was endorsed by Robert Bacher , also from Cornell, and one of the most senior scientists at Los Alamos. This led to an offer being made in August 1944, which Feynman accepted. Oppenheimer had also hoped to recruit Feynman to

9963-492: The parents as well as from more distant ancestors, the proportion of which varied for different traits. Karl Pearson was a follower of Galton , and although the two differed in some respects, Pearson used a substantial amount of Francis Galton's statistical concepts in his formulation of the biometrical school for inheritance, such as the law of regression. The biometric school, unlike the Mendelians , focused not on providing

10086-1041: The physical underpinnings of biomolecular phenomena. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA , RNA and protein biosynthesis , as well as how these interactions are regulated. A great variety of techniques are used to answer these questions. Fluorescent imaging techniques, as well as electron microscopy , x-ray crystallography , NMR spectroscopy , atomic force microscopy (AFM) and small-angle scattering (SAS) both with X-rays and neutrons (SAXS/SANS) are often used to visualize structures of biological significance. Protein dynamics can be observed by neutron spin echo spectroscopy. Conformational change in structure can be measured using techniques such as dual polarisation interferometry , circular dichroism , SAXS and SANS . Direct manipulation of molecules using optical tweezers or AFM , can also be used to monitor biological events where forces and distances are at

10209-727: The point that it would be possible to (as Feynman put it) " swallow the doctor ". The idea was discussed in Feynman's 1959 essay There's Plenty of Room at the Bottom . The studies of Luigi Galvani (1737–1798) laid groundwork for the later field of biophysics. Some of the earlier studies in biophysics were conducted in the 1840s by a group known as the Berlin school of physiologists. Among its members were pioneers such as Hermann von Helmholtz , Ernst Heinrich Weber , Carl F. W. Ludwig , and Johannes Peter Müller . William T. Bovie (1882–1958)

10332-459: The powerful new tool that Feynman had created. Computer programs were later written to evaluate Feynman diagrams, enabling physicists to use quantum field theory to make high-precision predictions . Marc Kac adapted Feynman's technique of summing over possible histories of a particle to the study of parabolic partial differential equations , yielding what is now known as the Feynman–Kac formula ,

10455-529: The project and was present at the Trinity nuclear test . Feynman claimed to be the only person to see the explosion without the very dark glasses or welder's lenses provided, reasoning that it was safe to look through a truck windshield, as it would screen out the harmful ultraviolet radiation. The immense brightness of the explosion made him duck to the truck's floor, where he saw a temporary "purple splotch" afterimage . Feynman nominally held an appointment at

10578-502: The question showed that the superfluid was displaying quantum mechanical behavior observable on a macroscopic scale. This helped with the problem of superconductivity , but the solution eluded Feynman. It was solved with the BCS theory of superconductivity, proposed by John Bardeen , Leon Neil Cooper , and John Robert Schrieffer in 1957. Feynman, inspired by a desire to quantize the Wheeler–Feynman absorber theory of electrodynamics, laid

10701-489: The scientific sense is thus essentially a product of the human mind and has no meaning apart from man." ( Ibid. , Ch. III, § 4) With significant post-war activity Pearson was a " zealous " atheist, " freethinker ", and socialist. He gave lectures on such issues as " the woman's question " (this was the era of the suffragist movement in the UK) and upon Karl Marx . His commitment to socialism and its ideals led him to refuse

10824-483: The sense of ideas or pictures in a mind . "There are many signs", he wrote, "that a sound idealism is surely replacing, as a basis for natural philosophy, the crude materialism of the older physicists." (Preface to second Ed., The Grammar of Science ) Further, he stated, "... science is in reality a classification and analysis of the contents of the mind ... In truth, the field of science is much more consciousness than an external world." ( Ibid. , Ch. II, § 6) "Law in

10947-405: The stock, owing to the conditions in which society has placed it, is able to increase its numbers." History shows me one way, and one way only, in which a high state of civilization has been produced, namely, the struggle of race with race, and the survival of the physically and mentally fitter race. If you want to know whether the lower races of man can evolve a higher type, I fear the only course

11070-752: The strengths of a department at a university differing emphasis will be given to fields of biophysics. What follows is a list of examples of how each department applies its efforts toward the study of biophysics. This list is hardly all inclusive. Nor does each subject of study belong exclusively to any particular department. Each academic institution makes its own rules and there is much overlap between departments. Many biophysical techniques are unique to this field. Research efforts in biophysics are often initiated by scientists who were biologists, chemists or physicists by training. Karl Pearson Karl Pearson FRS FRSE ( / ˈ p ɪər s ə n / ; born Carl Pearson ; 27 March 1857 – 27 April 1936 )

11193-626: The summer working on ballistics problems at the Frankford Arsenal in Pennsylvania . After the attack on Pearl Harbor brought the United States into the war, Feynman was recruited by Robert R. Wilson , who was working on means to produce enriched uranium for use in an atomic bomb , as part of what would become the Manhattan Project . At the time, Feynman had not earned a graduate degree. Wilson's team at Princeton

11316-710: The theoretical work and calculations on the proposed uranium hydride bomb , which ultimately proved to be infeasible. He was sought out by physicist Niels Bohr for one-on-one discussions. He later discovered the reason: most of the other physicists were too much in awe of Bohr to argue with him. Feynman had no such inhibitions, vigorously pointing out anything he considered to be flawed in Bohr's thinking. He said he felt as much respect for Bohr as anyone else, but once anyone got him talking about physics, he would become so focused he forgot about social niceties. Perhaps because of this, Bohr never warmed to Feynman. At Los Alamos, which

11439-512: The theoreticians were completely overshadowed by the achievements of the experimentalists, who reported the discovery of the Lamb shift , the measurement of the magnetic moment of the electron, and Robert Marshak 's two-meson hypothesis. Bethe took the lead from the work of Hans Kramers , and derived a renormalized non-relativistic quantum equation for the Lamb shift. The next step was to create

11562-436: The theory nearly simultaneously, Feynman's collaboration with Gell-Mann was seen as seminal because the weak interaction was neatly described by the vector and axial currents. It thus combined the 1933 beta decay theory of Enrico Fermi with an explanation of parity violation . Feynman attempted an explanation, called the parton model , of the strong interactions governing nucleon scattering. The parton model emerged as

11685-543: The theory of quantum electrodynamics , the physics of the superfluidity of supercooled liquid helium , and in particle physics , for which he proposed the parton model . For his contributions to the development of quantum electrodynamics, Feynman received the Nobel Prize in Physics in 1965 jointly with Julian Schwinger and Shin'ichirō Tomonaga . Feynman developed a widely used pictorial representation scheme for

11808-576: The theory would be extremely difficult to quantize, and Einstein said that one might try to apply this method to gravity in general relativity , which Sir Fred Hoyle and Jayant Narlikar did much later as the Hoyle–Narlikar theory of gravity . Feynman received a PhD from Princeton in 1942; his thesis advisor was John Archibald Wheeler . In his doctoral thesis entitled "The Principle of Least Action in Quantum Mechanics", Feynman applied

11931-493: The theory, which Feynman and Wheeler had tried, unsuccessfully, to work around. "Theoreticians", noted Murray Gell-Mann , "were in disgrace". In June 1947, leading American physicists met at the Shelter Island Conference . For Feynman, it was his "first big conference with big men ... I had never gone to one like this one in peacetime." The problems plaguing quantum electrodynamics were discussed, but

12054-508: The trained generation. Their children will not exhibit the learned improvements and, in turn, will need to be improved. "No degenerate and feeble stock will ever be converted into healthy and sound stock by the accumulated effects of education, good laws, and sanitary surroundings. Such means may render the individual members of a stock passable if not strong members of society, but the same process will have to be gone through again and again with their offspring, and this in ever-widening circles, if

12177-459: The use of which extends beyond physics to many applications of stochastic processes . To Schwinger, however, the Feynman diagram was "pedagogy, not physics". By 1949, Feynman was becoming restless at Cornell. He never settled into a particular house or apartment, living in guest houses or student residences, or with married friends "until these arrangements became sexually volatile". He liked to date undergraduates, hire prostitutes, and sleep with

12300-736: The verge of a new and glorious discovery. What Newton did to simplify the planetary motions must now be done to unite in one whole the various isolated theories of mathematical physics. Pearson then returned to London to study law, emulating his father. Quoting Pearson's own account: Coming to London, I read in chambers in Lincoln's Inn, drew up bills of sale, and was called to the Bar, but varied legal studies by lecturing on heat at Barnes, on Martin Luther at Hampstead, and on Lassalle and Marx on Sundays at revolutionary clubs around Soho. His next career move

12423-637: The wider public in the 1980s as a member of the Rogers Commission , the panel that investigated the Space Shuttle Challenger disaster . Along with his work in theoretical physics, Feynman has been credited with having pioneered the field of quantum computing and introducing the concept of nanotechnology . He held the Richard C. Tolman professorship in theoretical physics at the California Institute of Technology. Feynman

12546-676: The wives of friends. He was not fond of Ithaca's cold winter weather, and pined for a warmer climate. Above all, he was always in the shadow of Hans Bethe at Cornell. Despite all of this, Feynman looked back favorably on the Telluride House , where he resided for a large period of his Cornell career. In an interview, he described the House as "a group of boys that have been specially selected because of their scholarship, because of their cleverness or whatever it is, to be given free board and lodging and so on, because of their brains". He enjoyed

12669-575: Was a founder of the Men and Women's Club . Pearson was offered a Germanics post at King's College, Cambridge . Comparing Cambridge students to those he knew from Germany, Karl found German students inathletic and weak. He wrote to his mother, "I used to think athletics and sport was overestimated at Cambridge, but now I think it cannot be too highly valued." On returning to England in 1880, Pearson first went to Cambridge: Back in Cambridge, I worked in

12792-493: Was a keen popularizer of physics through both books and lectures, including a 1959 talk on top-down nanotechnology called There's Plenty of Room at the Bottom and the three-volume publication of his undergraduate lectures, The Feynman Lectures on Physics . Feynman also became known through his autobiographical books Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think? , and books written about him such as Tuva or Bust! by Ralph Leighton and

12915-573: Was also elected an Honorary Fellow of King's College, Cambridge, the Royal Society of Edinburgh, University College London and the Royal Society of Medicine, and a Member of the Actuaries' Club. A sesquicentenary conference was held in London on 23 March 2007, to celebrate the 150th anniversary of his birth. Articles Miscellany Most of the biographical information above is taken from

13038-404: Was an English biostatistician and mathematician . He has been credited with establishing the discipline of mathematical statistics . He founded the world's first university statistics department at University College London in 1911, and contributed significantly to the field of biometrics and meteorology . Pearson was also a proponent of Social Darwinism and eugenics , and his thought

13161-490: Was arrested on December 4, 1950 and emigrated to Brazil in October 1951. Because of the fears of a nuclear war, a girlfriend told Feynman that he should also consider moving to South America. He had a sabbatical coming for 1951–1952, and elected to spend it in Brazil, where he gave courses at the Centro Brasileiro de Pesquisas Físicas . In Brazil, Feynman was impressed with samba music, and learned to play

13284-422: Was born and the family moved to Far Rockaway, Queens . Though separated by nine years, Joan and Richard were close, and they both shared a curiosity about the world. Though their mother thought women lacked the capacity to understand such things, Richard encouraged Joan's interest in astronomy, and Joan eventually became an astrophysicist. Feynman's parents were both from Jewish families, and his family went to

13407-554: Was born in the United States into a Jewish family. Lucille's father had emigrated from Poland, and her mother also came from a family of Polish immigrants. She trained as a primary school teacher but married Melville in 1917, before taking up a profession. Feynman was a late talker and did not speak until after his third birthday. As an adult, he spoke with a New York accent strong enough to be perceived as an affectation or exaggeration, so much so that his friends Wolfgang Pauli and Hans Bethe once commented that Feynman spoke like

13530-416: Was clear: Shin'ichirō Tomonaga , Schwinger and Feynman understood what they were talking about even if no one else did, but had not published anything. He was convinced that Feynman's formulation was easier to understand, and ultimately managed to convince Oppenheimer that this was the case. Dyson published a paper in 1949, which added new rules to Feynman's that told how to implement renormalization. Feynman

13653-451: Was experimenting with mathematical topics such as the half-derivative using his own notation. He created special symbols for logarithm , sine , cosine and tangent functions so they did not look like three variables multiplied together, and for the derivative , to remove the temptation of canceling out the d {\displaystyle d} 's in d / d x {\displaystyle d/dx} . A member of

13776-503: Was interested in aspects of evolution such as heredity and eugenics . Pearson became Galton's protégé, at times to the verge of hero worship . After Galton's death in 1911, Pearson embarked on producing his definitive biography—a three-volume tome of narrative, letters, genealogies, commentaries, and photographs—published in 1914, 1924, and 1930, with much of Pearson's own money paying for their print runs. The biography, done "to satisfy myself and without regard to traditional standards, to

13899-404: Was isolated for security, Feynman amused himself by investigating the combination locks on the cabinets and desks of physicists. He often found that they left the lock combinations on the factory settings, wrote the combinations down, or used easily guessable combinations like dates. He found one cabinet's combination by trying numbers he thought a physicist might use (it proved to be 27–18–28 after

14022-490: Was no longer working at the Los Alamos Laboratory, he was no longer exempt from the draft . At his induction physical, Army psychiatrists diagnosed Feynman as suffering from a mental illness and the Army gave him a 4-F exemption on mental grounds. His father died suddenly on October 8, 1946, and Feynman suffered from depression. On October 17, 1946, he wrote a letter to Arline, expressing his deep love and heartbreak. The letter

14145-612: Was not only converted to other religious views, but I also stopped believing that the Jewish people are in any way 'the chosen people '". Later in life, during a visit to the Jewish Theological Seminary , Feynman encountered the Talmud for the first time. He saw that it contained the original text in a little square on each page, and surrounding it were commentaries written over time by different people. In this way

14268-499: Was probably the first job Feynman had, and during this time he showed early signs of an aptitude for his later career in theoretical physics, when he would analyze the issues theoretically and arrive at the solutions. When he was in grade school, he created a home burglar alarm system while his parents were out for the day running errands. When Richard was five, his mother gave birth to a younger brother, Henry Phillips, who died at age four weeks. Four years later, Richard's sister Joan

14391-607: Was prompted to publish his ideas in the Physical Review in a series of papers over three years. His 1948 papers on "A Relativistic Cut-Off for Classical Electrodynamics" attempted to explain what he had been unable to get across at Pocono. His 1949 paper on "The Theory of Positrons" addressed the Schrödinger equation and Dirac equation , and introduced what is now called the Feynman propagator . Finally, in papers on

14514-644: Was quickly promoted to a higher math class. An IQ test administered in high school estimated his IQ at 125—high but "merely respectable", according to biographer James Gleick . His sister Joan, who scored one point higher, later jokingly claimed to an interviewer that she was smarter. Years later he declined to join Mensa International , saying that his IQ was too low. When Feynman was 15, he taught himself trigonometry , advanced algebra , infinite series , analytic geometry , and both differential and integral calculus . Before entering college, he

14637-410: Was renaming two buildings which had been named after Pearson, because of his connection with eugenics. Karl Pearson was important in the founding of the school of biometrics, which was one of several competing theories to describe evolution and population inheritance at the turn of the 20th century. His series of eighteen papers, "Mathematical Contributions to the Theory of Evolution" established him as

14760-399: Was sealed and only opened after his death. "Please excuse my not mailing this," the letter concluded, "but I don't know your new address." Unable to focus on research problems, Feynman began tackling physics problems, not for utility, but for self-satisfaction. One of these involved analyzing the physics of a twirling, nutating disk as it is moving through the air, inspired by an incident in

14883-488: Was surprised by the offers of professorships from other renowned universities, including the Institute for Advanced Study , the University of California, Los Angeles , and the University of California, Berkeley . Feynman was not the only frustrated theoretical physicist in the early post-war years. Quantum electrodynamics suffered from infinite integrals in perturbation theory . These were clear mathematical flaws in

15006-490: Was to the Inner Temple , where he read law until 1881 (although he never practised). After this, he returned to mathematics, deputising for the mathematics professor at King's College, London in 1881 and for the professor at University College London in 1883. In 1884, he was appointed to the Goldsmid Chair of Applied Mathematics and Mechanics at University College London. Pearson became the editor of Common Sense of

15129-474: Was working on a device called an isotron, intended to electromagnetically separate uranium-235 from uranium-238 . This was done in a quite different manner from that used by the calutron that was under development by a team under Wilson's former mentor, Ernest O. Lawrence , at the Radiation Laboratory of the University of California . On paper, the isotron was many times more efficient than

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