The power of mathematics: applying the fundamentals to thinking

Toshiya ShimizuArtificial Intelligence Laboratory

Article｜2024-07-30

Studying and practicing mathematics

When I was in junior high school, my father introduced me to a mathematics book called "The Emotions of Imaginary Numbers," which sparked my interest in mathematics. The book was thick, a real tome with around 1,000 pages. It covered the history of mathematics, its applications to physics, and explained the challenges of tackling various mathematical problems. As I progressed through the book, I felt a growing desire to challenge unsolved mathematical problems and conjectures, and discovered the joy of learning new concepts.

The charm of mathematics lies in its apparent simplicity, which often turns out to be quite difficult when you actually try to solve a problem. While natural sciences gain understanding through observation, mathematics gains understanding through logical reasoning and abstract concepts. Through mathematics, I developed the habit of thoroughly examining the principles and foundations of things, and learned the importance of solidly understanding the basics. I decided to major in mathematics at university, because I wanted to explore mathematical theory deeply. When I was in graduate school, contemplating whether to continue research in pure mathematics or to use my mathematical knowledge to create technologies that benefit society, I encountered Fujitsu and discovered blockchain (*1) technology.

Connecting different blockchains

Blockchain technology plays a crucial role, relying heavily on cryptography and mathematical concepts. Drawn to Fujitsu's dedication to research and development in this field, where I could apply my mathematical skills and explore uncharted territories, I decided to join the company. Shortly after joining, I delved into the research and development of technology aimed at connecting different blockchains. Transactions between different blockchains present challenging issues regarding transparency when crossing chains. For instance, if one transaction fails to process, it may compromise the integrity of the entire transaction. In the early days of blockchain technology, a senior colleague and I tackled the task of devising a solution to such challenges, from conceptualization to implementation, resulting in a prototype for a token ledger that could interoperate.

This technology managed transaction records across systems using a ledger that ensured evidentiality, thereby guaranteeing transaction transparency. The prototype later evolved into the ConnectionChain (*2) technology, which eventually took the form of Hyperledger Cactus (*3), contributing to the development of open-source software infrastructure. It brings me immense joy to see that the technology I developed is now being used by so many. During that time, even amidst tight schedules, I dedicated ample time to fundamental learning. Blockchain technology requires knowledge spanning cryptography, databases, networks, and more. I believe that thorough study, leaving no ambiguity, ultimately facilitated the development of ideas and the resolution of questions, leading to fruitful outcomes.

Living life to the full! Including running, playing piano, and enjoying a good drink

After finishing work, I engage in about an hour of running almost every day. During middle and high school, I was a member of the track and field team, specializing in long-distance running. I've continued running for the sake of maintaining my health. It provides me with valuable time to organize my thoughts, as I sometimes come up with solutions to problems that I couldn't solve sitting at a desk, or new ideas emerge. Additionally, through running, I've built connections with fellow enthusiasts who share the same hobby. We share updates on each other's lives and engage in activities beyond work. Through such interactions, a wonderful community has formed, and I look forward to deepening these bonds in the future.

Apart from running, I started learning the piano about two years ago. Starting something from scratch as an adult can be challenging, but the desire to play classical and video game music sparked my interest. Although I could have continued playing the flute, which I learned during my student days, I was drawn to the expressive capabilities of the piano. I also appreciate a good drink, and it's common for my wife and I to have a drink together after work. In May 2024, we traveled to Belgium and enjoyed authentic Belgian beer together. Experiencing the local food and culture was a fantastic experience. Moving forward, I hope to continue exploring and broadening my horizons through various experiences.

Striving for AI technology that everyone can rely on

Recently, AI technologies such as ChatGPT and Diffusion models, which generate text and images, have been rapidly evolving. While AI supports us, its adoption and utilization can also give rise to new security challenges. In my current team, I am working on improving technology development for enhancing trustiness of AI, ensuring that users can use it with complete peace of mind. For example, it's essential to have knowledge of security measures not only for AI itself, but also to prevent attacks such as leaking excessive information from AI or inducing misjudgments by AI.

The current team fosters an atmosphere where members can openly exchange opinions and feel confident about freely speaking their mind. Additionally, there is diversity with many overseas members from Israel and the UK. Working alongside team members with a global perspective and overcoming various barriers, we are advancing cutting-edge research and development in a fast-paced environment. Users may not be consciously aware, but security technologies play an indispensable role in tandem with the rapid advancement of AI. I take pride in contributing to such research and being part of the team that supports technologies that users can confidently use.

Messages from colleagues

One of our top security researchers with the ability to analyze things from multiple perspectives and a unique viewpoint. Toshiya, who approaches his research with sincerity and passion, is highly respected within the company. (Yuki Unno, Data & Security Research Laboratory)

I have closely observed Toshiya's achievements since we were assigned to the same department as colleagues. His proposals for cutting-edge research themes, backed by extensive surveys, his speedy implementations, his easy-to-understand presentations with thorough logical structuring, and his accurate global discussions—all of these demonstrate his excellence in every aspect. To me, he is a leading light in our team! (Takanori Machida, Data & Security Research Laboratory)