Beating a computer at chess (max level)

Now and then I play a quick game of chess against on my mobile phone. We all know that computers are much better at the game nowadays. I’m impressed by the way modern chess computers play, and here’s another example. However, now and then I manage to beat the computer (AI Factory), which has an estimated elo rating of around 2000. Here’s a nice example of me winning a chess game against a computer at max level, within 20 moves:

“][Date “2019.04.11”][White “U”][Black “Cpu (12)”][PlyCount “37”][Result “1-0”]
1. e4 c5 2. Nf3 e6 3. d4 a6 4. d5 exd5 5. exd5 d6 6. c4 Bf5 7. Nc3 Nd7 8. Bd3 Ne7 9. O-O g6 10. Re1 Bxd3 11. Qxd3 Bg7 12. Bf4 Nb6 13. Ne4 Nb6c8 14. Bg5 O-O 15. Bf6 b5 16. Bxg7 Kxg7 17. Qc3+ Kh6 18. Nf3g5

Final position after Nf3-g5, in which black resigned. The black king is in trouble.

Member of the 1000-pound club

On Monday, March 24 2019, I became a member of the 1000-pound club.

Bench: 242 (110 kilo), Squat: 352 (160 kilo), Deadlift: 407 (185 kilo).

Many thanks to my personal trainer, Amir Sharyat who made this possible.

Doing sports helps me to stay fit and healthy, in particular when having a busy life (family, work, doing a PhD, teaching, etc.). Setting goals helps me to focus. Reaching the 1000-pound was one of such goals. It was fun to achieve this goal, although sometimes hard and frustrating (e.g. lacking 11 pounds (5 kilo) while giving all you’ve got).

Happy to see to have inspired others to follow and achieve the same goal. Who’s next?

Interestingly, my 1000-pound stats resemble that of Hugh Jackman.

Now all I need is a t-shirt.

Assessing Interoperability Solutions for Distributed Ledgers


Although distributed ledgers gradually become and accepted technology, there currently are some challenges that need to be solved. As nearly all current ledgers are siloed, one of those challenges is interoperability between ledgers. Interoperability, from a broad perspective, allows two different, separate ledgers to work with each other.

The need for interoperability is shown by the many initiatives that aim to achieve interoperability between distributed ledgers. Indeed, several solutions have been proposed and an initial classification of these solutions was proposed by Vitalik Buterin here.

The problem

However, it is not always clear which properties these solutions have, nor which particular issues exist in such solutions. This makes it hard to decide which solution to choose. Even more, some consequences of interoperability may be an argument for not interoperating with other ledgers.

Our work

In this (extended) paper we assess interoperability solutions for distributed ledgers. We propose 12 key properties with which we can distinguish between interoperability solutions in three ways.

First, we can distinguish between three kinds of interoperability solutions, being notary schemes, relay schemes, and hash-locking schemes. Second, these properties allow us to distinguish between subcategories of these kinds of solutions. And third, we can distinguish between generic and specific issues of these kinds of solutions.

Furthermore, by using these properties, we describe and analyze five real world solutions, being Polkadot, Cosmos, BTCRelay, Dogethereum and hashlocking schemes in general.

We discuss in detail the zone-spend attack. This attacks considers two interoperating ledgers, and under the assumption that one ledger uses a probabilistic consensus algorithm, we conclude that there exist a risk of creating an immutable, invalid state between the two ledgers, even if one of the ledgers uses a deterministic consensus algorithm. Note that no interoperability solution can mitigate this risk.

Finally we evaluate these 5 solutions and discuss several interoperability issues. We conclude that although the three kinds of solutions offer different functionalities, there exists an overlap of issues between these kinds of solutions. This is useful for deciding which interoperability solution to choose, and becoming aware of the current issues that come with each solution.

Our paper can be found here and feedback is, of course, welcome.

Blockchain Adoption Drivers @ LSDVE 2018

Blockchain may not always be the best suitable technology for a particular problem. However, we observe that blockchain is applied in many initiatives where alternative technologies fit better. Here, adoption of blockchain appears to be an irrational choice.

If blockchain is indeed not the best technical fit in these initiatives, then what drives blockchain adoption?

In August 2018, I presented our work at the Sixth Workshop on Large Scale Distributed Virtual Environments (LSDVE 2018). We propose both technical as well as non-technical blockchain adoption drivers. In particular, these non-technical driver may explain the rationality behind the seemingly irrational choices.

Our paper can be found here: drivers-blockchain-adoption v1.0

This is me, this is what I do

This is my first post online in a blog. Ever. After years of keeping a low online profile (due to previous work, and because it simply takes time), it was suggested to me to create a website, and post some of the things I do.

The short version is, I have a family, a full-time job at ING, I’m doing a part-time PhD, teach chess to kids, do weight-training multiple times a week, I love to read, play (video / board) games, and occasionally play one of my electric guitars. So, time is limited. Nevertheless, I’d call it an active life.

For the moment, my posts will be about my research, but I may add some other topic here as well. See you online!