Mathematics Is In Everything, Says Leslie Lamport At GYSS@one-north 2016

Mathematics is in everything around us, says eminent computer scientist and Turing Award winner Leslie Lamport.

AsianScientist (Jan. 22, 2016) – Mathematics is in everything around us, says eminent computer scientist Leslie Lamport, who is visiting Singapore as an invited speaker at the Global Young Scientists Summit@one-north 2016 this week.

Lamport has had a flourishing career in computer science at companies such as Massachusetts Computer Associates, SRI International, Digital Equipment Corporation and Microsoft Research, where he is now a principal researcher.

As a teenager, Lamport cut his teeth in programming after high school, when, “somewhat by accident,” he found a summer job running tapes in the computer room. Subsequent summers and spare time during graduate school were also devoted to programming.

But Lamport was trained in mathematics: he received a bachelor’s degree in mathematics from MIT in 1960, and a master’s degree and PhD degree in mathematics in 1963 and 1972 respectively, both from Brandeis University.

“When I finished my degree, I had the choice between teaching math at some university or going into computer science. I think I would have been a run-of-the-mill mathematician, but I turned out to be a good computer scientist,” he said with a laugh.

A delicious conundrum: the Bakery algorithm

Lamport’s youthful curiosity and love for problem-solving has persisted throughout his career, resulting in breakthroughs in several areas of computer science.

He first came to know of the problem of mutual exclusion when he stumbled upon Dutch computer scientist Edsger W. Djikstra’s 1965 paper on concurrent programming, “Solution of a Problem in Concurrent Programming Control.”

To understand what mutual exclusion is, the analogy of a bakery may be helpful: in a bakery, how do you ensure that customers approach cashiers one at a time, instead of bunching up at a single cashier? In computers, competing processes may try to write at the same time, which understandably may result in system failure.

It was this kind of computer puzzle that Lamport greatly enjoyed, and his solution, aptly named the Bakery algorithm, arranges competing processes according to their arrival order. In a bakery, it is akin to receiving a queue ticket and being sent to the next available cashier.

Lamport’s elegant, intuitive solution was instrumental in launching a new branch of computer science called distributed computing. By imposing coherence on seemingly chaotic behavior, software can function reliably even if it is running on a network of independent computers, and multiple cores of modern computer processors can also be coordinated.

Thinking precisely and abstractly

These days, Lamport wants to impart the following message to programmers: using mathematics allows you to approach coding in the way an architect would approach designing a building—both precisely and abstractly.

“Science requires precise thinking, and mathematics is what has developed over a couple of millennia as our best way of thinking precisely,” he said.

Programmers are taught to think about problems in terms of programming languages when instead, he maintained, problems should also be thought of at a more abstract level.

“Most programmers who lack [the ability to think abstractly], they just sit down and write code and it’s like somebody trying to build a table [without first thinking of] the concept of the circle. Just think, well, just cut out a piece of wood that’s sort of like this, with no idea why would cutting it out this way be better than cutting it out in a different way,” he explained.

Indeed, Lamport is adamant that programmers should think about and write down what a program is meant to do—its ‘blueprint’ or specification—before they actually start coding. Without this crucial step, it is inevitable that they will be troubleshooting bug after bug further down the line, he said.

A mathematics-based programming language that Lamport designed, TLA+, is based on the idea that the best way to describe things formally is by using simple mathematics.

And you don’t even need to be a mathematician to execute his programming language, he said. “The math you need is really very simple. Most people learn almost all of it in high school these days. But what you need to be taught is how to use that math to describe the systems you’re building.”

TLA+ in industry, space and beyond

Usage of TLA+ is ubiquitous in today’s world, with countless applications in industry and beyond. Programmers at Amazon Web Services use it routinely to build cloud infrastructure. Engineers at Intel use it when building computer chips. It has even reached the final frontier: the European Space Agency’s Rosetta spacecraft is currently on a comet, performing experiments that were designed using TLA+.

A little closer to home, Lamport shared an anecdote of how his programming language even helped Microsoft avert a near-certain disaster. While writing a TLA+ specification for an IBM-developed memory system chip in the Xbox 360, a Microsoft intern discovered a bug that would cripple the game console.

The IBM engineers’ first reactions were of disbelief, saying it could not possibly happen, Lamport said. However, they changed their tune a few weeks later.

“Their tests would not have discovered it, and had this intern not discovered this bug, it would have gone into production; every Xbox would have crashed after four hours of use. [That’s] a nice success story.”

Lamport has received many accolades during his long and illustrious career. The 1978 paper that started it all, titled “Time, Clocks, and the Ordering of Events in a Distributed System,” is one of the most cited in the history of computer science. Another of his papers, “Reaching Agreement in the Presence of Faults,” earned him the Edsger W. Djikstra Prize in 2005. Most notably, in 2013, he was awarded the A. M. Turing Award, the highest honor in computing and widely regarded as the Nobel Prize of the computer science world.

Microsoft co-founder Bill Gates himself has commended Lamport’s remarkable contributions to computer science, describing Lamport as “a leader in defining many of the key concepts of distributed computing that enable today’s mission-critical computer systems.”

“Leslie has done great things not just for the field of computer science, but also in helping make the world a safer place,” Gates wrote in 2014 regarding Lamport’s Turing Award win. “Countless people around the world benefit from his work without ever hearing his name.”

Asian Scientist Magazine is a media partner of the GYSS@one-north 2016.


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Coming from a design background, Filzah brings a fresh perspective to science communications. She is particularly interested in healthcare and technology.

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