The Grauniad reports on the death of adventurer and writer Patrick Leigh Fermor, aged 96. I recount a story about him and an ode by Horace, here.
Fermor attended Kit Marlowe’s old school, King’s School Canterbury, together with Alan Watts, who apparently wrote his first book about Zen Buddhism while still at school. Fermor famously was expelled from this school.
Writing in Bertinoro, Italy, I have just learnt of the death earlier this year of J. Martin Harvey (1949-2011), a friend and former colleague, and one of Zimbabwe’s great mathematicians.
Martin was the first black student to gain First Class Honours in Mathematics from the University of Rhodesia (as it then was, now the University of Zimbabwe), the first person to gain a doctorate in mathematics from that University, and the first black lecturer appointed to teach mathematics there. (Indeed, his three degree certificates name three different universities – London, Rhodesia, and Zimbabwe – but all were granted by the same physical institution.) He later became an actuary, one of the few of any colour in Zimbabwe, but this was a career that lost value with the declining Zimbabwe dollar: actuarial science is about financial planning under uncertainty, and planning is impossible and pointless in an economy with hyper-inflation. He then became part of the great Zimbabwean diaspora, lecturing at the University of the Western Cape, in South Africa.
Martin was a true child of the sixties, with all the best qualities of that generation – open, generous, tolerant, curious, unpompous, democratic, sincere. He was a category theorist, and like most, a deep thinker. Martin was a superb jazz flautist, and on his travels would seek out jazz musicians to jam with. He wrote and recited poetry, and indeed could talk with knowledge on a thousand topics.
I once spent a month traveling the country with him on a market research project we did together, and his conversation was endlessly fascinating. Despite our very different childhoods, I recall a long, enjoyable evening with him in a shebeen in rural Zimbabwe talking about the various American and Japanese TV series we had both seen growing up (which I mentioned here). Among many memories, I recall him once arguing that a university in a marxist state should have only two faculties: a Faculty for the Forces of Production, and a Faculty for the Relations of Production. There was great laughter as he insisted that the arts and humanities were essential to effective production, and so belonged in the former faculty; this argument was typical of his wit and erudition.
Our mutual friend, Professor Heneri Dzinotyiweyi, another great Zimbabwean mathematician, has a tribute here. I send my condolences to his wife, Winnie Harvey, and family. Vale, Martin. It has been an honour to have known you.
Bibliography:
J. M. Harvey [1983]: Categorical characterization of uniform hyperspaces. Mathematical Proceedings of the Cambridge Philosophical Society, 94: 229-233. Available here.
This short biography of Australian philosopher and computer scientist Charles L. Hamblin was initially commissioned by the Australian Computer Museum Society.
Charles Leonard Hamblin (1922-1985) was an Australian philosopher and one of Australia’s first computer scientists. His main early contributions to computing, which date from the mid 1950s, were the development and application of reverse polish notation and the zero-address store. He was also the developer of one of the first computer languages, GEORGE. Since his death, his ideas have become influential in the design of computer interaction protocols, and are expected to shape the next generation of e-commerce and machine-communication systems.
Continue reading ‘A salute to Charles Hamblin’
John Bennett AO (1921-2010), first professor of computing in Australia and founder of Sydney University’s Basser Department of Computer Science, died last month. The SMH obit, from which the lines below are taken, is here.
Emeritus Professor John Bennett AO was an internationally recognised Australian computing pioneer. Known variously as ”the Prof”, ”JMB” or ”Rusty”, he was a man with a voracious appetite for ideas, renowned for his eclectic interests, intellectual generosity, cosmopolitan hospitality and prodigious general knowledge.
As Australia’s first professor of computer science and foundation president of the Australian Computer Society, Bennett was an innovator, educator and mentor but at the end of his life he wished most to be remembered for his contribution to the construction of one of the world’s first computers, the Electronic Delay Storage Automatic Calculator (EDSAC). In 1947 at Cambridge University, as Maurice Wilkes’s first research student, he was responsible for the design, construction and testing of the main control unit and bootstrap facility for EDSAC and carried out the first structural engineering calculations on a computer as part of his PhD. Bennett’s work was critical to the success of EDSAC and was achieved with soldering irons and war-surplus valves in the old Cambridge anatomy dissecting rooms, still reeking of formalin.
. . .
The importance of his work on EDSAC was recognised by many who followed. In Cambridge he also pioneered the use of digital computers for X-ray crystallography in collaboration with John Kendrew (later a Nobel Prize winner), one of many productive collaborations.
He was recruited from Cambridge by Ferranti Manchester in 1950 to work on the Mark 1*. Colleague G. E. ”Tommy” Thomas recalls that when Ferranti’s promise to provide a computer for the 1951 Festival of Britain could not be fulfilled, ”John suggested … a machine to play the game of Nim against all comers … [It] was a great success. The machine was named Nimrod and is the precursor of the vast electronic games industry we know today.”
In 1952, Bennett married Mary Elkington, a London School of Economics and Political Science graduate in economics, who was working in another section at Ferranti. Moving to Ferranti’s London Computer Laboratory in 1953, Bennett worked in a team led by Bill Elliott, alongside Charles Owen, whose plug-in components enabled design of complete computers by non-engineers. Owen went on to design the IBM 360/30. Bennett remembered of the time, ”Whatever we touched was new; it gives you a great lift. We weren’t fully aware of what we were pioneering. We knew we had the best way but we weren’t doing it to convert people – we were doing it because it was a new tool which should get used. We knew we were ploughing new ground.”
Bennett was proud of being Australian and strongly felt the debt he owed for his education. When Harry Messel’s School of Physics group asked him in 1956 to head operations on SILLIAC (the Sydney version of ILLIAC, the University of Illinois Automatic Computer – faster than any machine then commercially available), he declined a more lucrative offer he had accepted from IBM and moved his family to Sydney.
The University of Sydney acknowledged computer science as a discipline by creating a chair for Bennett, the professor of physics (electronic computing) in 1961. Later the title became professor of computer science and head of the Basser department of computer science. Fostering industry relationships and ensuring a flow of graduates was a cornerstone of his tenure.
Bennett was determined that Australia should be part of the world computing scene and devoted much time and effort to international professional organisations. This was sometimes a trial for his staff. Arthur Sale recalls, ”I quickly learnt that John going away was the precursor to him returning with a big new idea. After a period when we could catch up with our individual work, John would tell us about the new thing that we just had to work on. Once it was the ARPAnet [Advanced Research Projects Agency Network] and nothing would suffice until we started to try to communicate with the Aloha satellite over Hawaii that had run out of gas to establish a link to Los Angeles and ARPAnet and lo and behold, the internet had come to Australia in the 1970s.”
In 1983, Bennett was appointed as an officer of the Order of Australia. After his retirement in 1986, he remained active, attending PhD seminars and lectures to ”stay up to date and offer a little advice” while continuing to earn recognition for his contributions to computer science for more than half a century.
Non-Australians are often unaware how fearful Australians were of being invaded by Japanese Imperial Forces during World War II. Australians had good reason to be fearful, since Japanese aircraft ran nearly 100 bombing raids on northern Australian towns and settlements, Japanese submarines planted mines in Sydney Harbour, submarines launched bombardments on both Sydney and Newcastle, and they harassed East Coast merchant shipping. The Japanese regime even printed special banknotes for use as currency in an occupied Australia. As a result, preparing for an invasion, Australian home forces were deployed, among other activities, in building tank traps – concrete pyramids intended to impede the advance of any invading tanks – on the main roads as far south as northern New South Wales (some 1500 miles down the east coast). The photo above shows an anti-tank trap at Paddy’s Flat near Jenny Lind Creek, Tabulam, northern NSW. A key election issue in the 1943 Federal Election was whether the Opposition parties, when previously in Government at the start of the war, had approved a plan to abandon the entire north of Australia above Brisbane to the invaders.
Several members of my family fought to defend Australia and the region from Japanese imperialism and fascism, and some died in that defence. Growing up with relatives, family friends, and acquaintances who’d been prisoners of war of the Japanese military perhaps gives one an acute sense of the myriad war crimes committed by those forces during that war, and of the many longer-term physical and psychological consequences of those crimes. Unlike former POWs of the Wehrmacht, most former POWs of the Japanese military refused to speak of their prison-camp experiences, so horrific and unspeakable were they, and many survivors found themselves unable to cope with everyday life when the war ended.
In the week of Remembrance Day, I wanted to honour those members of my family who fell fighting in that war, or afterwards from its traumas:
Con Hanley (1885-1944), Charles B. McBurney (1890-1943), Cecil C. Sexton (1915-1942), and Ron M. Hanley (1918-1946).
The philosopher George Santayana (1863-1952), whom I have written about before, was fortunate to have two families, one Spanish and one American. His mother was a widow when she married his father, and his parents later preferred to live in different countries – the USA and Spain, respectively. Santayana therefore spent part of his childhood with each, and accordingly grew up knowing his Bostonian step-family and their cousins, relatives of his mother’s first husband, the American Sturgis family. Among these relatives, his step-cousin Susan Sturgis (1846-1923) is mentioned briefly in Santayana’s 1944 autobiography (page 80). (See Footnote #1 below.)
Susan Sturgis was married twice, the second time in 1876 to Henry Bigelow Williams (1844-1912), a widower and property developer. In 1890, Williams commissioned a stained glass window from Louis Tiffany for the All Souls Unitarian Church in Roxbury, Massachusetts (pictured below), to commemorate his first wife, Sarah Louisa Frothingham (1851-1871).
The first marriage of Susan Sturgis was in 1867, to Henry Horton McBurney (1843-1875). McBurney’s younger brother, Charles Heber McBurney (1845-1913) went on to fame as a surgeon, developer of the procedure for diagnosis of appendicitis and removal of the appendix. The normal place of incision for an appendectomy is known to every medical student still as McBurney’s Point. The portrait below of Charles Heber McBurney was painted in 1911 by Ellen Emmet Rand (1875-1941), and is still in the possession of the McBurney family. (The painting is copyright Gerard McBurney 2013. As Ellen Emmet married William Blanchard Rand in 1911, this is possibly the first painting she signed with her married name.)
Charles H. McBurney was also a member of the medical team which treated US President William McKinley following his assassination. He and his wife, Margaret Willoughby Weston (1846-1909), had two sons, Henry and Malcolm, and a daughter, Alice. The younger son, Malcolm, also became a doctor and married, having a daughter, but he died young. Alice McBurney married Austen Fox Riggs (1876-1940), a protege of her father, Charles, and a pioneer of psychiatry. He founded what is now the Austen Riggs Centre in Stockbridge, MA, in 1907. They had two children, one of whom, Benjamin Riggs (c.1914-1992), was also a distinguished psychiatrist, as well as a musician, sailor, and boat builder. The elder son of Charles and Margaret, Henry McBurney (1874-1956), was an engineer whose own son, Charles Brian Montagu McBurney (1914-1979), became a famous Cambridge University archaeologist. CBM’s children are the composer Gerard McBurney, the actor/director Simon McBurney OBE, and the art-historian, Henrietta Ryan FLS, FSA. CBM’s sister, Daphne (1912-1997), married Richard Farmer. Their four children were Angela Farmer, a yoga specialist, David Farmer FRS, a distinguished oceanographer, whose daughter Delphine Farmer, is a chemist, Michael Farmer, painting conservator, and Henry Farmer, an IT specialist, whose son, Olivier Farmer, is a psychiatrist.
Henry H. and Charles H. had three sisters, Jane McBurney (born 1835 or 1836), Mary McBurney (1839- ), Almeria McBurney (who died young), and another brother, John Wayland McBurney (1848-1885). They were born in Roxbury, MA, to Charles McBurney and Rosina Horton; Charles senior (1803 Ireland – Boston 1880) was initially a saddler and harness maker in Tremont Row, Boston – the image above shows a label from a trunk he made. Later, he was a pioneer of the rubber industry, for example, receiving a patent in 1858 for elastic pipe, and was a partner in the Boston Belting Company. It is perhaps not a coincidence that Charles junior pioneered the use of rubber gloves by medical staff during surgery. All three boys graduated from Harvard (Henry in 1862, Charles in 1866, and John in 1869). John married Louisa Eldridge in 1878, and they had a daughter, May (or Mary) Ruth McBurney (1879-1947). May married William Howard Gardiner Jr. (1875-1952) in 1918, and on her death left an endowment to Harvard University to establish the Gardiner Professor in Oceanic History and Affairs to honour her husband. John worked for his father’s company and later in his own brokerage firm, Barnes, McBurney & Co; he died of tuberculosis.
Mary (or Mamie) McBurney married Dr Barthold Schlesinger (1828-1905), who was born in Germany of a Jewish ethnic background, and immigrated to the USA possibly in 1840, becoming a citizen in 1858. For many years, from at least 1855, he was a director of a steel company, Naylor and Co, the US subsidiary of leading steel firm Naylor Vickers, of Sheffield, UK. Barthold’s brother, Sebastian Benson Schlesinger (1837-1917), was also a director of Naylor & Co from 1855 to at least 1885; he was also a composer, mostly it seems of lieder and piano music; some of his music has been performed at the London Proms. At the time, Naylor Vickers were renowned for their manufacture of church bells, but in the 20th century, under the name of Vickers, they became a leading British aerospace and defence engineering firm; the last independent part of Vickers was bought by Rolls-Royce in 1999. Mary and Barthold Schlesinger appear to have had at least five children, Mary (1859- , married in 1894 to Arthur Perrin, 1857- ), Barthold (1873- ), Helen (1874- , married in 1901 to James Alfred Parker, 1869- ), Leonora (1878- , married in 1902 to James Lovell Little, c. 1875- ), and Marion (1880- , married in 1905 to Jasper Whiting, 1868- ). The Schlesingers owned an estate of 28 acres at Brookline, Boston, called Southwood. In 1879, they commissioned landscape architect Frederick Law Olmstead (1822-1903), the designer of Central Park in New York and Prospect Park in Brooklyn, to design the gardens of Southwood; some 19 acres of this estate now comprises the Holy Transfiguration Monastery, of the Greek Orthodox Church of North America. The Schlesingers were lovers of art and music, and kept a house in Paris for many years. An 1873 portrait of Barthold Schlesinger by William Morris Hunt (1824-1879) hangs in the Museum of Fine Arts in Boston.
While a student at Harvard, Henry H. McBurney was a prominent rower. After graduation, he spent 2 years in Europe, working in the laboratories of two of the 19th century’s greatest chemists: Adolphe Wurtz in Paris and Robert Bunsen in Heidelberg. Presumably, even Harvard graduates did not get to spend time working with famous chemists without at least strong letters of recommendation from their professors, so Henry McBurney must have been better than average as a chemistry student. He returned to Massachusetts to work in the then company, Boston Elastic Fabric Company, of his father, and then, from November 1866, as partner for another firm, Campbell, Whittier, and Co. From what I can discover, this company was a leading engineering firm, building in 1866 the world’s first cog locomotive, for example, and, from 1867, manufacturing and selling an early commercial elevator. Henry H. and Susan S. McBurney had three children: Mary McBurney (1867- , in 1889 married Frederick Parker), Thomas Curtis McBurney (1870-1874), and Margaret McBurney (1873-, in 1892 married Henry Remsen Whitehouse). Mary McBurney and Frederick Parker had five children: Frederic Parker (1890-), Elizabeth Parker (1891-), Henry McBurney Parker (1893-), Thomas Parker (1898.04.20-1898.08.30), and Mary Parker (1899-). Margaret McBurney and Henry Whitehouse had a daughter, Beatrix Whitehouse (1893-). The name “Thomas” seems to have been ill-fated in this extended family.
HH died suddenly in Bournemouth, England, in 1875, after suffering from a lung disease. As with any early death, I wonder what he could have achieved in life had he lived longer.
POSTSCRIPT (Added 2011-11-21): Henry H. McBurney’s visit to the Heidelberg chemistry lab of Robert Bunsen is mentioned in an account published in 1899 by American chemist, Henry Carrington Bolton, who also worked with Bunsen, and indeed with Wurtz. Bolton refers to McBurney as “Harry McBurney, of Boston” (p. 869).
POSTSCRIPT 2 (Added 2012-10-09): According to the 1912 Harvard Class Report for the Class of 1862 (see Ware 1912), Henry H. McBurney spent the year from September 1862 in Paris with Wurtz and the following year in Heidelberg with Bunsen. He therefore presumably just missed meeting Paul Mendelssohn-Bartholdy (1841-1880), son of composer Felix, who graduated in chemistry from Heidelberg in 1863. PM-B went on to co-found the chemicals firm Agfa, an acronym for Aktien-Gesellschaft für Anilin-Fabrikation. I wonder if Paul Mendelssohn-Bartholdy ever returned to visit Bunsen in the year that Henry McBurney was there.
POSTSCRIPT 3 (Added 2013-01-20): I am most grateful to Gerard McBurney for the portrait of Charles H. McBurney, and for additional information on the family. I am also grateful to Henrietta McBurney Ryan for information. All mistakes and omissions, however, are my own.
NOTE: If you know more about any of the people mentioned in this post or their families, I would welcome hearing from you. Email: peter [at] vukutu.com
References:
Henry Carrington Bolton [1899]: Reminiscences of Bunsen and the Heidelberg Laboratory, 1863-1865. Science, New Series Volume X (259): 865-870. 15 December 1899. Available here.
George Santayana [1944]: Persons and Places: The Background of My Life. (London, UK: Constable.) (New York, USA: Charles Scribner’s Sons.)
Charles Pickard Ware (Editor) [1912]: 1862 – Class Report – 1912. Class of Sixty-Two. Harvard University. Fiftieth Anniversary. Cambridge, MA, USA, Available here.
Footnotes:
1. Santayana writes as follows about Susan Sturgis Williams (Santayana 1944, page 74 in the US edition):
Nothing withered, however, about their sister Susie, one of the five Susie Sturgises of that epoch, all handsome women, but none more agreeably handsome than this one, called Susie Mac-Burney and Susie Williams successively after her two husbands. When I knew her best she was a woman between fifty and sixty, stout, placid, intelligent, without an affectation or a prejudice, adding a grain of malice to the Sturgis affability, without meaning or doing the least unkindness. I felt that she had something of the Spanish feeling, So Catholic or so Moorish, that nothing in this world is of terrible importance. Everything happens, and we had better take it all as easily or as resignedly as possible. But this without a shadow of religion. Morally, therefore, she may not have been complete; but physically and socially she was completeness itself, and friendliness and understanding. She was not awed by Boston. Her first marriage was disapproved, her husband being an outsider and considered unreliable; but she weathered whatever domestic storms may have ensued, and didn’t mind. Her second husband was like her father, a man with a checkered business career; but he too survived all storms, and seemed the healthier and happier for them. They appeared to be well enough off. In her motherliness there was something queenly, she moved well, she spoke well, and her freedom from prejudice never descended to vulgarity or loss of dignity. Her mother’s modest solid nature had excluded in her the worst of her father’s foibles, while the Sturgis warmth and amiability had been added to make her a charming woman.”
POST MOST RECENTLY UPDATED: 2013-03-26.
The death has occurred of Australian journalist Murray Sayle (1926-2010) whose reports from Japan I particularly remember. Harold Jackson has an amusing reminiscence of their time together in Prague, in the immediate aftermath of the Warsaw Pact invasion in August 1968, here. In addition to enjoying his writing, I always felt a personal link to Sayle, in a 6-degrees-of-separation way: he was a school-friend of my late headmaster Colin Meale, who introduced me to the symphonies of Dmitri Shostakovich. As I recall, Col did not much like the music of his younger brother Richard, though.
Col’s fast-witted son Tony I remember here.
A family member has just been posted to Iraq for the first time, so I here send my best wishes for a safe deployment and return.
I use this opportunity to remember the one person I know who has not returned from there: Lt Tom Mildinhall, of 1st The Queen’s Dragoon Guards, musician and graduate in AI, who died on 28 May 2006, and whom I first met at a performance of Elijah in St Paul’s Church, Hammersmith, in 2000. The Evening Standard on 17 March 2008 ran a story about him, containing tributes from his family and friends. Another report about him is here. May he rest in peace.
I have posted before about how the history of commercial computing is intimately linked with the British tea-shop, via LEO, a successful line of commercial computers developed by the Lyons tea-shop chain. The first business application run on a Lyons computer was almost 60 years ago, in 1951. Today’s Grauniad carries an obituary for John Aris (1934-2010), who had worked for LEO on the first stage of an illustrious career in commercial IT. His career included a period as Chief Systems Engineer with British computer firm ICL (later part of Fujitsu). Aris’ university education was in Classics, and he provides another example to show that the matherati represent a cast of mind, and not merely a collection of people educated in mathematics.
John’s career in computing began in 1958 when he was recruited to the Leo (Lyons Electronic Office) computer team by J Lyons, then the major food business in the UK, and initiators of the notion that the future of computers lay in their use as a business tool. At the time, the prevailing view was that work with computers required a trained mathematician. The Leo management thought otherwise and recruited using an aptitude test. John, an Oxford classics graduate, passed with flying colours, noting that “the great advantage of studying classics is that it does not fit you for anything specific”. “
Of course, LEO was not the first time that cafes had led to new information industries, as we noted here in a post about the intellectual and commercial consequences of the rise of coffee houses in Europe from the mid-17th century. The new industries the first time round were newspapers, insurance, and fine art auctions (and through them, painting as a commercial activity aimed at non-aristocrat collectors); the new intellectual discipline was the formal modeling of uncertainty (then aka probability theory).
UPDATE (2012-05-22): The Telegraph of 2011-11-10 ran an article about the Lyons Tea Shop computer business, here, to celebrate the 60th anniversary of the LEO (1951-11-17).
Howard Gardner’s theory of multiple intelligences includes an intelligence he called Logical-Mathematical Intelligence, the ability to reason about numbers, shapes and structure, to think logically and abstractly. In truth, there are several different capabilities in this broad category of intelligence – being good at pure mathematics does not necessarily make you good at abstraction, and vice versa, and so the set of great mathematicians and the set of great computer programmers, for example, are not identical.
But there is definitely a cast of mind we might call mathmind. As well as the usual suspects, such as Euclid, Newton and Einstein, there are many others with this cast of mind. For example, Thomas Harriott (c. 1560-1621), inventor of the less-than symbol, and the first person to draw the moon with a telescope was one. Newton’s friend, Nicolas Fatio de Duiller (1664-1753), was another. In the talented 18th-century family of Charles Burney, whose relatives and children included musicians, dancers, artists, and writers (and an admiral), Charles’ grandson, Alexander d’Arblay (1794-1837), the son of writer Fanny Burney, was 10th wrangler in the Mathematics Tripos at Cambridge in 1818, and played chess to a high standard. He was friends with Charles Babbage, also a student at Cambridge at the time, and a member of the Analytical Society which Babbage had co-founded; this was an attempt to modernize the teaching of pure mathematics in Britain by importing the rigor and notation of continental analysis, which d’Arblay had already encountered as a school student in France.
And there are people with mathmind right up to the present day. The Guardian a year ago carried an obituary, written by a family member, of Joan Burchardt, who was described as follows:
My aunt, Joan Burchardt, who has died aged 91, had a full and interesting life as an aircraft engineer, a teacher of physics and maths, an amateur astronomer, goat farmer and volunteer for Oxfam. If you had heard her talking over the gate of her smallholding near Sherborne, Dorset, you might have thought she was a figure from the past. In fact, if she represented anything, it was the modern, independent-minded energy and intelligence of England. In her 80s she mastered the latest computer software coding.”
Since language and text have dominated modern Western culture these last few centuries, our culture’s histories are mostly written in words. These histories favor the literate, who naturally tend to write about each other. Clive James’ book of a lifetime’s reading and thinking, Cultural Amnesia (2007), for instance, lists just 1 musician and 1 film-maker in his 126 profiles, and includes not a single mathematician or scientist. It is testimony to text’s continuing dominance in our culture, despite our society’s deep-seated, long-standing reliance on sophisticated technology and engineering, that we do not celebrate more the matherati.
On this page you will find an index to Vukutu posts about the Matherati.
FOOTNOTE: The image above shows the equivalence classes of directed homotopy (or, dihomotopy) paths in 2-dimensional spaces with two holes (shown as the black and white boxes). The two diagrams model situations where there are two alternative courses of action (eg, two possible directions) represented respectively by the horizontal and vertical axes. The paths on each diagram correspond to different choices of interleaving of these two types of actions. The word directed is used because actions happen in sequence, represented by movement from the lower left of each diagram to the upper right. The word homotopy refers to paths which can be smoothly deformed into one another without crossing one of the holes. The upper diagram shows there are just two classes of dihomotopically-equivalent paths from lower-left to upper-right, while the lower diagram (where the holes are positioned differently) has three such dihomotopic equivalence classes. Of course, depending on the precise definitions of action combinations, the upper diagram may in fact reveal four equivalence classes, if paths that first skirt above the black hole and then beneath the white one (or vice versa) are permitted. Applications of these ideas occur in concurrency theory in computer science and in theoretical physics.