Chess #1353

The Moscow Grand Prix has generated plenty of excitement and upsets. The semi-final lineup is Hikaru Nakamura Vs Alexander Grischuk and Ian Nepomniachtchi Vs Radoslaw Wojtaszek, and the first round of the semis ended in two draws. Top seed Anish Giri was knocked out in the first round by Daniil Dubov while Levon Aronian lost to Nepomniachtchi. 

In a broader sense, it would surprising if there were no surprises in a KO format. At this level, with an all 2,700-plus field, most games at classical time controls end in draws. But rapid and blitz tiebreakers guarantee a result, which will always be a bit of a lottery — somebody will make catastrophic errors and you don’t know who. 

The French Top 12 Club championship holds some special interest for India since a lot of Indians play for the French clubs. Pentala Harikrishna plays on Board 2 for Asnieres - Le Grand Echiquier behind Maxime Vachier-Lagrave. Nihal Sarin is on the Philidor Mulhouse team while Cannes has Karthikeyan Murali, Rameshbabu Praggnanandhaa and Gukesh D. Round four saw Sarin versus Gukesh in a key game, which Sarin won. 

Meanwhile the TCEC (Top Computer Engine Championship) Superfinal is on and Leela Chess Zero  is likely to take revenge for “her” narrow 50.5- 49.5 loss to Stockfish in 2018. After 75 games, Leela leads 40-35. The TCEC is played on the same hardware at classical controls. 

Leela Chess Zero uses self-learning via Monte-Carlo — the methods DeepMind introduced with AlphaZero. The program teaches itself with analysis done by rapidly playing out positions with random move choices. This leads it to assess moves on probabilistic basis, and it creates a “weight” file, where it incorporates what it has learnt. The weight file is updated as it learns more. Leela runs on almost any computer with any OS, and it’s freely downloadable along with the latest weights. It runs much faster with dedicated Graphic Processor Units (GPUs) and RAM to spare. 

Stockfish is also a free engine which works on any platform (including Android where Leela doesn’t work well). But Stockfish is programmed the standard way by incorporating rules for evaluation into the program and the move search and selection uses normal alpha-beta methods. Leela was first released in January 2018 and is now into version 21.1. It seems to have learnt more than Stockfish in the 18 months of development. 

The diagram, White to Play (White: Dubov Vs Black: Giri, Moscow GP 2019, Rd 1, Game 2) is a completely crazy position. White played 35. Ndc6 Qc5 36. Ne7+ Kh8 (1-0). Try working out why Giri resigned without an engine.  Answer: White plays 37. Nxf7+ and 37. – Rfxf7 38. Rd8+ or 37. – Rhxf7 38. Qh6+ leads to mate. 

Devangshu Datta is an internationally rated chess and correspondence chess player