About the Hong Kong Laureate Forum



Welcome to the July 2021 issue of the newsletter of the Hong Kong Laureate Forum!

While the inaugural Forum would be deferred for one year to November 2022, our work on fostering exchanges among scientists of different generations, cultures and disciplines; promoting understanding and interests of young generation in various disciplines in science and technology will not slow down. The HKLF is organising a series of pre-Forum events to continue our effort in facilitating networking among young scientists from different parts of the world and to beat the drum for the inaugural Forum. The "Prelude to the Inaugural Forum" would include "Science Exposition", which showcases the research achievements of Hong Kong; "Masterminds, Masterclasses", seminars by and dialogues with world-renowned scientists; "Exploring New Horizons", an opportunity to witness promising scientists at work; "Wonder Women in Science – Inspiring and Empowering the Next Generation", which showcases and affirms women’s contribution in science as well as promotes women’s wider participation in science. A press event "Beckoning the Inaugural Hong Kong Laureate Forum" will also be held to kick start the inaugural Forum.

For our online game "Your Fame, Its Name", which ended on 9 July, we received more than 70 entries in total after two rounds of the Game. The winners were chosen after consolidating the scores by the judging panelists and the votes cast by more than 800 visitors to our Facebook page. Their entries were indeed very interesting and engaging. Once again, congratulations to the winners of the game, who had collected their prizes with glee. Special thanks to the three judging panelists, they are:

- Mr SHUN Chi-ming, SBS, former Director of the Hong Kong Observatory
- Dr TONG Shiu-sing Dominic, The Chinese University of Hong Kong
- Dr HO Koon-sing, the Hong Kong Baptist University

We will continue to launch interesting and informative science games and promote science in the community.

Please stay tuned to our website and social media channels for more information on the "Prelude to the Inaugural Forum" and science games!

Last but not least, the Shaw Laureates 2021 were announced on 1 June 2021 at a press conference held by The Shaw Prize Foundation.

The Shaw Prize in Astronomy is awarded in equal shares to Prof Victoria M Kaspi of McGill University, Canada and Prof Chryssa Kouveliotou of George Washington University, USA for their contributions to our understanding of magnetars, a class of highly magnetised neutron stars that are linked to a wide range of spectacular, transient astrophysical phenomena. Through the development of new and precise observational techniques, they confirmed the existence of neutron stars with ultra-strong magnetic fields and characterised their physical properties. Their work has established magnetars as a new and important class of astrophysical objects.

The Shaw Prize in Life Science and Medicine is awarded to Prof Scott D Emr of Cornell University, USA for the landmark discovery of the ESCRT (Endosomal Sorting Complex Required for Transport) pathway, which is essential in diverse processes involving membrane biology, including cell division, cell-surface receptor regulation, viral dissemination, and nerve axon pruning. These processes are central to life, health and disease.

The Shaw Prize in Mathematical Sciences is awarded in equal shares to Prof Jean-Michel Bismut of Université Paris-Saclay, France and Prof Jeff Cheeger of New York University, USA for their remarkable insights that have transformed, and continue to transform, modern geometry.

Congratulations to the five Shaw Laureates 2021! The Award Ceremony for The Shaw Prize 2021 will again be presented online this year and is scheduled to be held in October this year. Stay tuned to The Shaw Prize website and social media as well as ours for further information!

Early History of the Hong Kong Observatory



The need for an observatory

Since 1841, Hong Kong became an important port of trade. In order to ensure smooth port operations and safe navigation of ships, there was a need to provide accurate time service. In the last edition of the Hong Kong Laureate Forum Newsletter, Mr SHUN Chi-ming, former Director of the Hong Kong Observatory (HKO), discussed the important role that astronomical observations played in maritime navigation, especially the need for an accurate clock onboard for determining latitude and longitude at sea. Initially, the time service was provided by the Noonday Gun, which was fired daily at noon. However, by 1861, people began to question the accuracy of this method, and there were calls to provide a more accurate time service based on scientific methods.

Located on the southern coast of China, Hong Kong is susceptible to typhoons between the months of May to November every year. As early as the 18th century, foreign merchants working in Huangpu Port and the ‘Thirteen Factories’ in Guangzhou wrote detailed records of typhoons and their impacts. In July 1841, shortly after the British occupation of Hong Kong, a typhoon almost claimed the lives of Gordon BREMER, Commander-in-chief of the British forces in the area and pivotal figure in the First Opium War, and Charles ELIOT, the first Administrator of Hong Kong. A few decades later in September 1874, one of the strongest typhoons in Hong Kong’s history caused serious damage across Hong Kong and Macau, killing over 2,000 people in Hong Kong and 5,000 people in Macau – approximately 8% of its population. In the aftermath of these disasters, there was an urgent need for an organisation that could predict the arrival of storms and issue warnings.

 

Authors:
Mr SHUN Chi-ming, Former Director of the Hong Kong Observatory
Dr LEE Tsz-cheung, Senior Scientific Officer, Hong Kong Observatory
Dr CHENG Cho-ming, Director of the Hong Kong Observatory

A Glimpse into the Applications of Mean Field Games



Mean field game (MFG) theory studies the strategies of agents of a large population in a competitive environment. Each agent seeks to maximise its own benefit according to the actions of other agents surrounded. For example, in the stock market, each trader buys or sells a certain number of shares based on other traders’ strategies in order to maximise his / her rates of return. The term "mean field" comes from physics, which means that the behaviour of an individual agent in a large population has negligible impact upon the system. In a typical MFG, an agent behaves based on the distribution of the states of other agents instead of reacting upon the behaviour of other agents individually. For instance, in a shopping market, a customer can buy some good after knowing the trading information of other customers and sellers, which is somehow impossible and troublesome. Instead, in a mean field scenario, he / she can decide based only on the price of the good, which simplifies the decision. In the market, the price is formed through the interaction of buyers and sellers. Thus, it encodes the probabilistic distributions of the states and strategies of all the agents in the market. The price, viewed as a mean field, enormously saves the time of making decisions.

 

Author:
Dr MOU Chenchen, Assistant Professor, Department of Mathematics, City University of Hong Kong

MythBusters: Black Holes

Black Holes: A Brief Introduction

Although the existence of black holes was first speculated in the 18th century, they were first scientifically predicted by Einstein’s theory of general relativity as a solution to the Einstein field equations. Einstein’s theory of relativity can be elegantly summed up in twelve words from John Wheeler – "Space-time tells matter how to move; matter tells space-time how to curve."

Mass bends the fabric of space-time itself; around a black hole’s event horizon, the space-time is bent in a way that even light cannot escape. This occurs when the size of a star collapses to a small enough size – more specifically, smaller than the Schwarzschild radius, . (Here M is the mass of the star, c is the speed of light, and G is the gravitational constant.)

To put things into perspective, if the Sun were a black hole, it would have a radius of approximately 2.95 km; in comparison, the current radius of the Sun is 696,340 km. Actually, owing to the relatively tiny mass of the Sun, it can never turn into a black hole – so we won’t have to worry about our Sun turning into a black hole any time soon!

The black holes we can see in the sky are formed by a process known as gravitational collapse. In a dying star, there is a reduction in internal pressure due to the fusing of heavier elements. As the internal pressure continues to decrease, gravity causes the star to further collapse onto itself. Eventually, the density of the star becomes high enough that it creates a very strong gravitational pull – and this is a black hole. You may recall the concept of escape velocity from high school physics; black holes are so small and massive that the escape velocity is greater than the speed of light. Nothing escapes a black hole – not even light.

 

Author:
Ms Sonia Choy
Student Editor, Science Focus
The Hong Kong University of Science and Technology