A viewer watches a light projection showed on the facade of the Hungarian Science Academy as a side event of the World Science Forum in Budapest, Hungary on Nov. 21, 2019. (Photos: Attila Volgyi/Xinhua)

Light projection is showed on the facade of the Hungarian Science Academy as a side event of the World Science Forum in Budapest, Hungary on Nov. 21, 2019.

Light projection is showed on the facade of the Hungarian Science Academy as a side event of the World Science Forum in Budapest, Hungary on Nov. 21, 2019.

Light projection is showed on the facade of the Hungarian Science Academy as a side event of the World Science Forum in Budapest, Hungary on Nov. 21, 2019.

Viewers watch a light projection showed on the facade of the Hungarian Science Academy as a side event of the World Science Forum in Budapest, Hungary on Nov. 21, 2019.