Thursday, November 16, 2006
Monday, October 02, 2006
Rabin and me at Manor Junior School – 1974 - 1978
Our first year teacher at Manor was Miss Thomas, a Welsh lady with red hair and a rather shaky grasp of spelling. In the second year, we had the truly scary Miss Blunden – if two children were sent by another teacher to give her a message, she would ask them why it took two of them to deliver the message – yes, that scary. In the third year we had the gentle Miss Hawton and then in our last year the beautiful but forbidding Mrs Harvey (nee Murphy – or Mrs Murphy, nee Harvey, I can’t recall which, now). For an unfashionable London suburb Barking had some fairly exotic inhabitants at this time. There were children from the Indian sub-continent, China, sub-Saharan Africa and the Caribbean at the school. There were also the children of people who had fled the Vietnamese war and its aftermath – what were termed in the media at the time, the ‘Vietnamese Boat people’. But Rabin seemed to me to be truly global. My geography was rather sketchy at the time, but I was aware of an Indian connection, a Middle Eastern link and an association with America.
Rabin himself was without a doubt unique. My abiding impression of him is that he was very serious. But looking at all the photos on the website he is always smiling, so I think it was probably just that he was seriously clever. We would spend hours together after school or during the holidays either in my garden shed, our bedrooms or his conservatory at 35 Edgefield Avenue. We didn’t play so much as ‘work on projects’ – hare-brained schemes usually thought up by me (the fantasist) which would then have to be implemented as far as was possible given our limited resources by Rabin (the genuine child prodigy). A working car which we could tour the world in built entirely out of Meccano; a rocket to send our Action Men into space, and so on. Rabin would spend most of these sessions instructing me in the art of the possible and coming up with workable alternatives to satisfy my childish imagination – so the Meccano car became a small but very serviceable crane; the space rocket a helicopter back-pack for an Action Man using a small electric motor etc. In fact electric motors and circuits with light-bulbs formed a very important part of our relationship for a period, which is not as odd as it sounds for two 8 year old boys.
Occasionally we would take a break from our scientific endeavours and I would coach Rabin at football, this being a suitable trade for the hard science that he imparted to me. Rabin was the first person to tell me about things like the Theory of Relativity and quantum mechanics. Even at this young age he seemed really to understand these things: I just marveled at them, and at him for knowing about them. The other thing that interrupted our important and ground-breaking work on Action Man propulsion systems, was the marvelous food made by Rabin’s Mum. I remember Rabin’s Mum having the most delightful smile and a lovely gentle nature which I think Rabin inherited from her.
Even Rabin’s bedroom was unique. His endlessly inventive Dad, whom I revered as a sort of suburban Carl Sagan, had suspended his bed from the ceiling with metal pipes, to give him more room. This was for us an incredibly exciting development which I never tired of seeing. Rabin’s Dad had done all sorts of interesting things in his life. One that stuck in my memory was that whilst in Canada* he had driven several different cars during a single day. I can’t remember why, or what job had involved this feat, but I was extremely impressed by it.
The scope of Rabin’s knowledge was certainly not confined to the natural sciences. He also had insights in fields such as psychology. I remember him confiding to me that he thought one of our rather highly strung schoolmates was probably suffering from a psychological disorder. I can’t recall what exactly his diagnosis was, but it was the first time it had occurred to me that people can break down too.
I was interested, but not at all surprised, to hear that Rabin had mastered Japanese. I recall an early example of Rabin’s analytical approach to language. There’s a road in Barking called Beccles Drive – pronounced ‘Beckals’, like ‘Eccles’ cake. One day walking back from school he challenged the accepted pronunciation saying that as it had a double ‘C’ it should be pronounced ‘Beck-les’. I wasn’t sure, but Rabin was quite adamant. I think in this instance Rabin may have got a little carried away by his own logic (it’s definitely pronounced like ‘Eccles’!), but it is an example of him analyzing and challenging received views at a very young age.
The other area of occasional collaboration between us was in the field of music. Rabin played the violin and I played the trumpet. Rabin played in the string orchestras conducted by the peripatetic teacher, Mr Stuckey. Anyone who has ever heard a Junior School string orchestra (and I understand that they are much rarer now than they used to be) will be acquainted with the fact that young children generally don’t have the motor skills required to produce a truly musical effect on string instruments (I think this is a charitable as I can be on this). Any fool can blow into a trumpet. But to tease a rich, sustained note out of a violin or cello requires a real touch which kids just don’t have. Rabin, as I recall, actually played very well, but as a rule, the string orchestras produced a rather thin, reedy sound. Not to worry though, because Mr Stuckey would compensate by humming the melody over the top of the orchestra – the perfect solution! For the finale of our summer school concert the senior string orchestra would be joined by the senior choir and part of the brass band to form a kind of super-group (think Bayreuth meets the Minipops!). I remember in our final concert together we played the Ode to Joy from Beethoven’s 9th Symphony. Coming as it did at the end of the summer term of our last year at Manor, this was probably the last thing that Rabin and I collaborated on.
All-in-all I doubt whether I made as lasting an impression on Rabin as he left on me, except perhaps in one respect. Some of you may have noticed that Rabin had a slight scar on his top lip – just to the right of centre. I see from the photos on the website that it was still visible when he was an adult. That, I’m afraid, was me. We were kicking a Coke can to each other in the street outside Manor Junior School after school one day in summer. I kicked it a bit too hard, and the coke can hit the edge of a paving stone and reared up hitting Rabin on the lip and giving him quite a deep cut. I always felt guilty about this. Rabin was a very gentle person, not naturally aggressive in the way that you need to be to be competitive in sports. By contrast, I was quite competitive and I think on this occasion I had kicked the tin can as hard as I could to put it past him. I hope the scar didn’t give him trouble shaving in later life.
Kids create their own worlds with a large measure of imagination and perhaps aren’t the most reliable witnesses. But this is how I remember it. I’m sorry I missed the opportunity to compare notes with Rabin – he might have remembered it more clearly. He made a greater impression on me than these few reminiscences can convey and I will always remember him.
*Note from Rabin’s father - Rabin’s father was teaching in Canada. His class wanted to visit the Science Fair in Toronto. To raise funds for the visit a car ‘Washaton’ was organized. The teacher, Rabin’s father, was the only one allowed to move the cars – this was approximately 120 vehicles of various descriptions – all this in one day.
Friday, June 23, 2006
I arrived at QMW in 1990, from small town Scotland, to do an MSc in the computer science department and my first memory of Rabin is of an enigmatic figure bobbing about in the labs in the ITL building wearing a fedora. I got to know that he was one of the notorious "ACE" lab people, a scary bunch interested in the details of computer graphics. As time went on and I became more of a fixture in the department myself, I joined in on some of the "departmental walks". It turned out that Rabin went on these too and I began to get to know him a bit better. He became known as "Teflon man" as no matter what state the rest of us were in, Rabin never had a speck of dirt on him. I also came to know that he drove very, very fast! Walks led to cycles and Rabin took part in these too…thrashing around the backroads of Kent.
Then there were the numerous evenings spent in the luxurious SCR bar, talking total rubbish…well, some of us talked rubbish, I don’t think Rabin ever did. It was there that I began to find out about Rabin’s incredible depth and breadth of knowledge. He could bring a drunken debate to a halt with one incisive statement of fact. I also began to find out that Rabin loved food, another common interest. He became renowned for ordering the weirdest thing on the menu…and actually eating it (and usually insisting that everyone else did too).
Anyway, we all left QMW (eventually) to do our various things. However, we still met up fairly frequently for beer and food and more drunken debate, we still do. For some reason I still hang on to the last email I have from Rabin suggesting a night out...
The last time I saw Rabin was in my own home, he was telling us that our imported Japanese beer wasn’t actually brewed there. Although it said "brewed in the Czech Republic" on the bottle, I’m pretty sure Rabin could really tell just from the taste.
I never heard Rabin say a word in anger, he could be animated, frustrated maybe, but never angry. His dry wit was also legendary as were his kindness and generosity. I wouldn’t claim that I knew him well, there were aspects of him that I really still know nothing about…his opinions on religion or politics for instance. However, I was always finding out more about him, what he was into, discovering common interests along the way. I would've enjoyed finding out more.
Perhaps the most amazing thing I’ve found out about him is that he and I share a birthday.
I miss him but I’m really glad that our worlds collided.
Saturday, November 19, 2005
In 1993-1994, the main workstations that students used were SunOS boxes with 68020 processors. Rabin and the rest of us in the graphics group were always looking for faster processors to run our calculations on - this in the days when SGI workstations were still few and far between because they were so expensive. So where to find this extra compute power? The workstations were running jobs over night anyway and we had no time-sharing system in the department.
This was a common problem, but someone, Rabin perhaps, had discovered that there was a faster processor available - on the printer! The laser printer had a 68030 processor, and for a short time this was one of the fastest compute machines in the department. So someone was encoding their jobs as Postscript and sending them to the printer to "execute" - the output being printed on the piece of paper. So some print jobs were suspiciously taking a very long time to come out!
Perhaps someone who knew Rabin better at the time can correct this - I only really knew him well after we had left QMW. In case anyone think this story a bit too unlikely, take a look at this URL - a working raytracer you can send to your Postscript printer.
Monday, August 22, 2005
I first met Rabin Ezra some time in the second half of the 1980s. I taught the Computer Graphics course, a final year course at Queen Mary and
During the course itself I had several after-class discussions with him, and it was during one of these that the issue of his staying on to do a PhD arose. He was very interested in hardware for real-time computer graphics. Also I had read a very interesting paper by some people at Sun Microsystems that provided a very efficient method for the rendering of curves and surface that would be amenable to hardware implementation. Rabin became interested in this and we agreed upon this as his topic. He started the PhD probably in 1988.
He made rapid progress and actually soon had a hardware design for the main part of the surface generation graphics hardware. He passed his first and second year vivas without trouble. But then he did run into trouble. It seemed to be a trivial problem. Suppose you are given n points in 3D space. You need to decide if all these points are approximately on a plane. Mathematically this is not difficult. Take any three of the points that are not themselves on a straight line, and from these find the equation of the plane that passes through them. Then for each of the remaining points find their distance from this plane, and if the maximum distance of all these points from the plane is less than a certain fixed and given tolerance, then we can say that ‘approximately’ (how approximate depends on the chosen tolerance) the points are flat, i.e., are on a plane. Mathematically this is trivial. Transforming it into an efficient and accurate computer program is less trivial. Fitting it into a hardware design architecture so that it doesn’t become a major bottleneck is very difficult. This is what occupied Rabin for the remainder of his PhD. Finding some workable solution to this problem took about 2 years.
In January 1991 I took sabbatical leave from QMW to take a Visiting Professorship at
I was offered additional semesters (this time paid) by
During this period Rabin and I had agreed that he would begin writing his PhD. One day shortly after I had returned to Berkeley Rabin sent me an email: “I’ve finished!”. I was very surprised. A PhD thesis normally runs to about 150 pages. Had he written so much, with all the references and all the figures, in such a short time? I asked him to send me the thesis. Well what he had written was fine – but it was about 40 pages in length. He had succinctly stated the problem, and the solution and results, in as terse manner as possible. There was nothing at all wrong with it, except that it really was too terse. So over the next year or so we gradually got more and more flesh put on the bare bones of the thesis. It was somehow against Rabin’s nature to spell things out in detail. “It’s obvious” he would say, "why should I have to write about it?" Well, obvious to him, and to me, but to the examiners, and other readers? – not so obvious. Yes, things have to spelled out, in detail. Where does this equation come from? Why is this statement true? What reference do you have to back up this idea? With some resistance Rabin eventually saw the light. But in a way of course Rabin was right. He had stated the problem and given the solution and results. Really of course the rest is convention. This is how a PhD is supposed to look. To be awarded a PhD he had to learn to follow certain conventions. But … they are only conventions.
He finally submitted in late 1993 or early 1994. The thesis length was still quite short, but acceptable.
On the day of the viva he was extremely nervous, to the point of shaking visibly – Rabin was not one for formally speaking in public, and he would have to do a short presentation in front of the two examiners. I told the examiners about his state. One of whom was Dr Simon Arridge from University College London who said I should tell Rabin not to worry, everything was ok. This did seem to quieten his nerves somewhat, and although still visibly shaking when he did his presentation, he got through it well. In the ensuing viva period he relaxed and engaged in genuine discussion with the examiners, and nothing remarkable happened. He was awarded the PhD.
After the award of the PhD Rabin went to work for Canon Research Europe where he specialised in graphics hardware and software, and especially on the interface between the two. CRE was partially founded by an ex-QMW student, and a number of ex-QMW people eventually worked there.
I kept in touch with Rabin over the years, and in particular used to meet him annually at the SIGGRAPH meeting in the
Rabin is unforgettable. Although I will never see him physically again, he is still around. Although he passed away before SIGGRAPH 2005, I believe that he was still there, and enjoyed it as usual. He lives on at least through our memories and in our hearts.
Thursday, August 18, 2005
A good friend
In latter years, as we have got older and ever more busy, it has become more difficult to arrange to meet up as a large group. However Rabin always made the effort to come along, even if it was just a couple of us meeting for a drink, or the occasional barbecues some of us hold. Out of all my friends I think he was the most intelligent, ethical, and dependable. I won't forget him.