Sameen Ahmed Khan, Dept. Mathematics & Sciences, Salalah, Sultanate
On 14 November 2017, the UNESCO (United Nations Educational, Scientific and Cultural Organization) proclaimed 16 May as the International Day of Light (IDL), during the 39th Session of the UNESCO General Conference. The inaugural day was celebrated in 2018. The IDL was endorsed by the Executive Board of the UNESCO in October 2016. The press release at that milestone stated ‘The purpose of an International Day of Light is to provide an annual focal point for the continued appreciation of the central role that light plays in the lives of the citizens in the world in areas of science, culture and art, education, sustainable development, and in fields as diverse as medicine, communications and energy’ [1–3].
The International Day of Light is a direct and enduring legacy of the International Year of Light and Light-based Technologies (IYL2015). We recall the relevant details regarding IYL2015. The IYL2015 was proclaimed by the United Nations General Assembly 68th Session on 20 October 2013. The resolution for the IYL2015 was presented to the United Nations General Assembly by UNESCO in 2013 [4–7]. IYL2015 recorded 93 National Nodes . IYL2015 led to 13,168 events in 147 countries with about 23,000 mentions in the media of 120 countries. The estimated audience is believed to be over a hundred million. To mark the year, thirty countries issued commemorative postage stamps and currency coins [1, 8, 9]. Undoubtedly, IYL2015 has been one of the most successful International Years of the UNESCO. Moreover, it is one of the few science related years, which were also endorsed by the United Nations.
The first laser was demonstrated on 16 May 1960 by engineer and physicist Theodore Harold Maiman using a synthetic-ruby crystal . At that time Maiman (1927-2007) was at the Hughes Research Laboratories, a Division of Hughes Aircraft Company, Malibu, California, USA. Maiman’s demonstration made use of a solid-state flash-lamp-pumped synthetic-ruby crystal and produced a red laser light at 6943Å(694.3 nanometres). The three-level pumping design scheme limited Maiman’s laser to pulsed operation. Historically, this demonstration turned out to be ahead of several other teams including that of Charles Hard Townes (who received the 1964 Nobel Prize in Physics with Nicolay Gennadiyevich Basov and Aleksandr Mikhailovich Prokhorov), Arthur Leonard Schawlow (who received the 1981 Nobel Prize in Physics with Nicolaas Bloembergen and Kai Siegbahn) and Gordon Gould . It is to be noted that Maiman’s single author report in Ref.  acknowledges the joint article by Schawlow and Townes . Laser science has evolved over the decades and has found applications in numerous disciplines including healthcare and telecommunications. Many discoveries in recent decades have made use of lasers and over twenty of the Nobel Laureates are related to lasers and arising from its diverse applications . We shall consider an example from physics and chemistry each. In 1965, Charles Kuen Kao achieved the transmission of light in fibers for optical communication . Ahmed Hassan Zewail (1999 Chemistry Nobel Laureate) pioneered the use of lasers to probe chemical reactions .
The International Day of Light was introduced to UNESCO by sponsors Ghana, Mexico, New Zealand and the Russian Federation, and supported at the UNESCO Executive Board and the General Conference by 27 countries: Argentina, Colombia, Czech Republic, Democratic Republic of Congo, Dominican Republic, Ecuador, Egypt, Finland, Iran, Ivory Coast, Kenya, Lebanon, Madagascar, Malaysia, Morocco, Nicaragua, Serbia, South Africa, Sudan, Sweden, Nigeria, Paraguay, Qatar, Togo, Vietnam, Uganda and Zimbabwe. The International Day of Light is administered from UNESCO’s International Basic Science Programme by a Steering Committee that also includes representatives from: the American Institute of Physics (AIP), the American Physical Society (APS), Bosca beverages, the European Centres for Outreach in Photonics (ECOP), the European Physical Society (EPS), the International Association of Lighting Designers (IALD), the Abdus Salam International Centre for Theoretical Physics (ICTP), the IEEE Photonics Society (IPS), the International Commission on Illumination (CIE), lightsources.org - the international network of accelerator based light sources, Light: Science and Applications, the Optical Society (OSA), Philips Lighting, the International Society for Optics and Photonics (SPIE), the Synchrotron-Light for Experimental Science and Applications in the Middle East (SESAME) and Thorlabs (optical instruments company, New Jersey, USA) .
As the light sciences play an important role in the various facets of human endeavours, the logo of the International Day of Light has incorporated the logo of the Sustainable Development Goals (SDGs). It is to be recalled that the SDG’s emerged from the 2015 United Nations Summit for its 2030 Agenda for Sustainable Development. The SDG’s are a successor of the Millennium Development Goals. There are 17 Global Goals, which are measured by progress against 169 specific targets [15, 16]. The goals are: 1. No Poverty, 2. Zero Hunger, 3. Good Health and Well-Being, 4. Quality Education, 5. Gender Equality, 6. Clean Water and Sanitation, 7. Affordable and Clean Energy, 8. Decent Work and Economic Growth, 9. Industry, Innovation and Infrastructure, 10. Reduced Inequalities, 11. Sustainable Cities and Communities, 12. Responsible Consumption and Production, 13. Climate change, 14. Life Below Water, 15. Life on Land, 16. Peace, Justice and Strong Institutions, and 17. Partnerships for the Goals.
The inaugural International Day of Light was marked in a grand ceremony at the UNESCO Headquarters in Paris, France on 16 May 2018. The Illuminating Education Conference is the Flagship Celebration of the International Day of Light 2019, scheduled to be held at the Abdus Salam International Centre for Theoretical Physics, Trieste, Italy on 16 May 2019. The expected worldwide annual events will provide a platform to highlight the role of light sciences in fields as diverse as medicine, communication. John Michael Dudley (working at the CNRS-University of Franche-Comté joint research institute in Besançon, France) had served as the Chairman of the IYL2015 International Steering Committee [4, 8, 9]. Now, he is serving as the IDL Steering Committee Chair . There are 67 National Nodes (including India) recorded at the IDL website and this figure is sure to increase .
The IDL is aimed at stimulating worldwide interest, especially among young people in light and related sciences & technologies. It will highlight to the citizens of the world the importance of light and optical technologies in their lives, for their futures, and for the development of society. A variety of events and activities will be organized world-wide. In view of the strong relationship between the world of accelerators and light sciences, IDL will be an excellent platform to conduct accelerator related outreach programmes. Cornerstone projects such as a Synchrotron Day or Synchrotron Week (or an Accelerator Day or Accelerator Week) can be organized, when synchrotron radiation facilities (and other accelerator facilities) around the world will open their doors to public visitors. This will enable to highlight the role of accelerators in human endeavours, ranging from basic particle physics research to diverse applications in medicine and industry .
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