Britain is to be no country for an 'old' physicist and polymath of genius called Professor David Mackay

David, whose stomach cancer has robbed Britain of one of its brightest of academic stars, has died at the age of 48. From the time when he was a brilliant undergraduate at Trinity College Cambridge in the 1980's, to when his condition caught up with him last year, he achieved much in diverse scientific fields.

David first announced his cancer on his blog, 'Everything is Connected' in 2015 http://itila.blogspot.co.uk/2015/08/unexpected-signs-of-malignancy.html in a post entitled :  'Unexpected signs of malignancy' :
'My doctor told me something on Thursday 16th July 2015, and I'm going to write about it here. I noticed that my doctor told me in a slightly oblique way, flying past the central topic a few times, using slightly technical language, and emphasising how unexpected the information was. Somehow, this emphasis on the unexpectedness of the information made it comfortable to absorb. 
My doctor got straight to the point: tests had been done on biopsies from my endoscopy; the letter from the hospital said the ulcer showed signs of malignancy, most unexpectedly.
"Malignant adenocarcinoma", he said.
"That's a cancer of the glandular tissue", he said.'

David was born in the spring of 1967 in Stoke on-Trent, the youngest son, in a family of five, of Valerie and Donald, who in turn had been born the son of a GP in Caithness Scotland in the northern fishing village of Lybster. During the Second World War Donald had spent three years working on radar research and before David was born, had moved in 1960 to the new, University of Keele in Staffordshire where he set up the renowned 'Department of Communication and Neuroscience.' His innovative concept had been to use the language of information science as the lingua franca for the interdisciplinary team he assembled of physiologists, psychologists, physicists and engineers investigating the sensory communication systems of the brain and their disturbance in blindness and deafness.

Donald was a leading thinker for 'Research Scientists Christian Fellowship' and John S.North gave a glimpse into family life for young David when he wrote of Donald that he 'had dined with his family in their home on the outskirts of Keele, joining him, his wife Valerie and their five children, as they considered the Scriptures and prayed for each other at the end of a busy day.'

Donald was 45 when David was born and already had a son and three daughters and was only 65 when he died after a long battle with cancer when David was an undergraduate at Trinity College. A man of equanimity of whom North said that he 'maintained an attitude both gentle and tenacious in the discussions, however ill-informed or ill-mannered the questioner. These two experiences provided the confirming reassurance that this intellectual is a person of warmth, strength, consistency and wholeness.'  We must assume he exercised a big influence on his young son, although you wouldn't know it from David, who said that from the age of 5 to 10 : 'I ate salted porridge for breakfast every day, went to school, played soccer and rounders' and from 11 to 18 he 'learnt at the excellent grammar school in Newcastle-Under-Lyme and came home to a wonderful dinner.' In addition, he 'played judo, hockey, violin and viola and rode my bike a lot. I only went to one disco, so I still have a good sense of hearing and my clothes don't smell of beer and cigarettes.' In the fifth year at school, when he was 15 in 1982, he sat prominently, second from the left in Form 5 beta in the form photo with Bill Beaton his form tutor and biology teacher..

In his last year at school David recalled : 'When I was 18, I represented Britain at the 'International Physics Olympiad' in Yugoslavia and had a great time with the Germans and Canadians ' and won first prize in the 'Practical' and then it was off to follow in his elder brother, Robert's footsteps and take up his place at Trinity College Cambridge, but to study Natural Sciences in the Department of Engineering, rather than Mathematics, which was : 'good fun. I looked after a punt and played croquet and lived in Great Court for a year. In the holidays I climbed mountains in Wales and Scotland. After my finals in Physics I rowed for a couple of weeks, went down four in the First and Third fifth boat, and experienced the 'May Week Boatie Dinner' at Trinity, which was of course in June - which all makes sense to anyone who's been at Cambridge.'

He recalled that at the age of 19 and in his second year at Trinity : 'My first research work was in 1986 at RSRE Malvern, where I was given the task of testing high precision digitizers statistically, by putting in uniformly distributed random voltages and looking at the distribution of digital read-outs. That summer I sent a contribution to an 'Institute of Physics' Magazine, giving a solution to the problem of constructing a spiral mirror. Other topics that amused me at that time were : the construction of astrolabes and making a learning-and-prediction program which attempted to predict the next digit in a human-generated binary sequence.'

At the age of 21, after graduation in 1988, David, the brilliant scholar, recalled : 'I made a difficult choice between going to Caltech and Edinburgh for my PhD. Caltech won.' So it was off to the USA and a PhD in 'Computation and Neural Systems' as a Fulbright Scholar at the California Institute of Technology where he discovered that he : 'cared about green politics and founded Caltech Environmental Task Force. I bought a car, Caltech is in L.A. and realised that I didn't want to live in a car society. Caltech was a great scientific place, but I wanted to get back to the green spaces of Cambridge as quick as possible.'

In 1988 he was involved in research involving the fruit fly, drosophila 'which had had a p-element inserted in the genome. I looked at polka-dot expression patterns in the brains of larvae and adults and found a few interesting patterns, including one strain in which the stained cells appeared to be associated with the optic chiasm of the adult.'

Back in Britain at the age of 25 in 1992 he was 'lucky to get a superb postdoc as a research fellow at Darwin College', the Royal Society Smithson Research Fellow and 'bought a house and a number of bicycles, including a Brompton and a tandem' and 'started playing Ultimate on Jesus Green (right) with a nice bunch of psychologists' and 'after a few years became a lecturer in the Physics Department.'

He also recorded in the same year that : 'back in Cambridge, I worked on defending my thesis against the attacks of David Wolpert (left) and others. I did this by writing review papers, writing a paper on 'optimization versus `integrating out' hyperparameters' and entering the American Society of Heating Refrigeration and Air Conditioning Engineers 'Prediction Competition' using my software.'


In 1995 he started what would become a 640-page textbook on 'Information Theory, Inference, and Learning Algorithm' which, when completed in 2003, he said had started as : 'a tiny, elegant (?) 8 chapters for an 8-lecture course on Information Theory; the book gradually expanded as I taught a 16-lecture course in the Physics Department.' In addition, 'The book's growth was partly driven by complaints that the brief exposition was too brief, so I felt obliged to fill in omitted steps and arguments. Guess what? I then received complaints about the filled-in steps and arguments, so those had to be expanded too. The book also grew because of my lack of self-control : I recklessly added new topics to the book. For me, everything is connected, and it was great fun to include all the things I was interested in - for example, my paper on evolution, sex, and information theory : rather than go through the inevitable tribulations of submitting it to a conventional journal, hey, just slip it in the book!'

Away from the laboratory, David helped in the successful campaign to 'Free Sally Clark', the solicitor wrongly convicted in 1999 of murdering her two baby sons. Although he didn't know her, he volunteered to set up and maintain her campaign website free of charge and helped to use mathematical arguments of probability to demonstrate the unsoundness of the original conviction.

1999 was the year he started his major new research project, 'Dasher', a software tool for disabled users which allowed them to write text as fast as normal handwriting using a single finger or head-mounted pointer and created "a new metaphor for what writing is. Instead of writing is 'pressing buttons', or 'scribbling with a stick', writing is n'avigating in a library of all possible books'." https://www.youtube.com/watch?v=0d6yIquOKQ0 "It's just like driving a car. We want it to be very simple for people to learn and the idea is : you point where you want to go." https://www.youtube.com/watch?v=0d6yIquOKQ0&t=2m44s By 2003 he had 'made a useable breath-mouse and demonstrated that writing at 12 words per minute was possible by breath alone.'

In 2000 his 5-strong Cavendish Laboratory Research Group, including 23 year old Seb Wills (left), won 'The Mouse Brain Competition' : a  puzzle set by two researchers in America, John Hopfield and Carlos Brody. The first part of the challenge was to explain how a simulated `mouse brain' made up of about a thousand neurons performed speech recognition and the second part of the contest required entrants to construct their own simulated brain, capable of speech recognition on a ten-word vocabulary. Apparently they cracked the computational principles underlying the `mouse' after a one-hour brain-storming meeting and David said : "I knew we had solved it' when our tentative explanation started predicting curious details in the recordings from the "brain"'.  The team donated their prize money to the 'Free Sally Clark' Campaign.

While all members of the Group had physics degrees, it worked on a wide range of topics in addition to Dasher : error-correcting codes for communication systems, the search for 'gene expression patterns' in data from cancer patients and research into effective physics teaching methods. David said, in a direct echo of his Father's inter-disciplinary approach : "the boundaries between departments are outdated. I've always been interested in the whole of science - I have collaborations with engineers, computer scientists, materials scientists, psychologists statisticians, pathologists and physiologists. To be a good scientist, you need to be curious and to have an urge to get to the bottom of things. I would find it impossible to be curious about physics alone. I'm grateful to the Physics Department for giving my group a home where we can pursue research without frontiers."

In 2003, the year he became 'Professor of Natural Philosophy', he developed, with his older brother, Robert, Professor of Mathematics at Warwick, 'an explicit theory of how biological systems such as actin/myosin convert chemical energy efficiently into work' and also 'became involved in the African Institute for Mathematical Sciences, a new institute in South Africa providing a one-year course for African graduates in mathematical sciences' and spent roughly 8 weeks per year there in academic years between 2003 and 2006.

In 2005 David became interested in the global energy crisis and started writing a popular book tentatively titled `You Figure It Out'' and three years later published 'Sustainable Energy - without the hot air' which he made available free online before hardback publication in 2009. He said that he had decided to write the book because he was tired of the “greenwash” surrounding the energy and climate change issue :  “I was tired of the debate – the extremism, the nimbyism, the hairshirt. We need a constructive conversation about energy, not a Punch and Judy show. I wanted to write a book about our energy options in a neutral, human-accessible form.”

David's genius was to express all forms of power consumption and production in a single unit of measurement – kilowatt hours per day and in an easy to understand : a 40 watt light bulb, kept switched on all the time, uses one kWh/d. So driving the average car 50km a day consumes 40 kWh/d. Such comparisons, David argued, helped to shift the focus to the major issues away from much-hyped 'eco-gestures' such as believing you have done your bit by remembering to switch off the mobile phone charger. 'The amount of energy saved by switching off the phone charger is exactly the same as the energy used by driving an average car for one second' and Switching it off for a year saves as much energy as is needed for one hot bath. He saw such gestures were akin to 'bailing out the Titanic with a teaspoon.' https://www.youtube.com/watch?v=UR8wRSp2IXs&t=0m51s

Within two years his book had sold more than 40,000 copies in print and been downloaded about 400,000 times and having been made a Fellow of the Royal Society in 2009, it is no surprise that he was appointed 'Chief Scientific Advisor to the Department of Energy and Climate Change' from 2009, a role he undertook until 2014 and involved him in encouraging students to take part in the 'British Physics Olympiad' where they would : 'Have fun problem solving, test their knowledge with stimulating questions and see the real-world problem-solving potential of Physics.' David also served as a member of the 'World Economic Forum Global Agenda Council on Climate Change.'

On April 10, just four days before his death, he posted an 'open letter' to the Directors of Addenbrooke’s Hospital in Cambridge prompted by his sleepless nights in a hot ward and in which he wrote: “The hospital is a great one, the staff are wonderful, and I’m grateful for everything the NHS does for me here. But I do have just one impassioned question and plea... Why oh why oh why does the room not have any semblance of intelligent thermal environmental control?”

In 2010 David published his recipe of 'How to make Porridge' and finished with :

'On birthdays and other special occasions it is permitted to add raisins   and or golden syrup.
                          For me, every day is a special occasion.
                            I add a large spoon of golden syrup

In his last blog post on April 12 David said, when it came to making gifts :

'I'll set up a JustGiving site, dedicated to the Arthur Rank Hospice Charity.'

 Thank you for all the warm messages from everyone!
https://www.justgiving.com/davidjcmackay?utm_source=email&utm_medium=emails-from-eua&utm_content=shorturl&utm_campaign=eua-email-sponsorshiprequest