الْحَمْدُ لِلّهِ الَّذِي خَلَقَ السَّمَاوَاتِ وَالأَرْضَ وَجَعَلَ الظُّلُمَاتِ وَالنُّورَ ثُمَّ الَّذِينَ كَفَرُواْ بِرَبِّهِم يَعْدِلُونَ
All praise is due to Allah, Who created the heavens and the earth and made the darkness and the light; yet those who disbelieve set up equals with their Lord. [6-1]
M Shakir's Quran Translation
Electromagnetic Spectrum and Visible Light
Light is a basic requirement of life. Without light one cannot see his surroundings. The waves that accompany light are made up of oscillating, or vibrating, electric and magnetic fields, which are force fields that surround charged particles and influence other charged particles in their vicinity. These waves are known as electromagnetic waves. The electromagnetic spectrum refers to the entire range of frequencies or wavelengths of electromagnetic waves.
Light is traditionally referred to the range of frequencies of the electromagnetic spectrum that is visible to humans.
The electromagnetic spectrum includes radio waves, microwaves, infrared light, visible light, ultraviolet light, x rays, and gamma rays. Visible light, which makes up only a tiny fraction of the electromagnetic spectrum, is the only electromagnetic radiation that humans can perceive with their eyes.
From the above figure it is pretty evident that the visible spectrum is only a small portion of the electromagnetic spectrum. A tiny fraction of frequencies from 1 Hz to 1026 Hz is what the human eye can perceive. Visible light spectrum has very high frequencies i.e. from 5 x 1014 to 7.5 x 1014 Hz and their wavelength is from 400 nanometers to 700 nanometers. Each different frequency or wavelength of visible light causes our eye to see a slightly different color. The longest wavelength we can see is deep red at about 700 nm. The shortest wavelength humans can detect is deep blue or violet at about 400 nm.
Absence of light is normally termed as darkness but, in the light of the above information, to our naked eye darkness should be termed as the absence of electromagnetic waves in the visible light spectrum. So, when Quran mentions 'making of darkness' it is accurate in the sense that those electromagnetic waves which we cannot see are also 'made' but for us they are a part of 'darkness'. It is a striking fact that such accurate information exists in a 14 centuries old book.
Using the word Darkness in Plural form
Another interesting fact is that in this Ayat and in many other Ayaats Quran uses the word darkness as pluralظلمات and the word lightنور as singular. Quran uses the word ظلمات23 times i.e. the plural form of darkness and it always uses the word نور i.e. the singular form of light. The singular of ظلمات is ظلمة. Imam Raaghib says that it means the absence of light. Remember Quran also uses the terms darkness and light analogous to guidance and ignorance. Even in those cases Quran uses darkness in plural form and light (guidance) in singular form because there are many paths that are wrong but the real true path is only one which Quran terms as the 'صراط مستقيم'. In this Ayat when Allah mentions the process of creation, He uses plural form for darkness and singular form for light pointing to the striking fact which modern science has only recently discovered.
As described above visible light spectrum is only a portion of the large 'variety' of frequencies ranging from 1 Hz to 1026 Hz. Visible light spectrum has ranges from 5 x 1014to 7.5 x 1014 Hz. Quran is very accurate in using the plural for darkness (frequencies other than the visible spectrum) because they have much greater range of frequencies. Hence, we can safely conclude that in Quranic terms used in this Ayat نور is the 'visible light spectrum' and ظلملت are X-Rays, gamma Rays, Ultraviolet rays etc.
Ayaats in which the Quran uses the word ظلمات
Surah Baqarah 2:17, Surah Baqarah 2:19, Surah Baqarah 2:257, Surah Maida 5:16, Surah Anaam 6:1, Surah Anaam 6:39, Surah Anaam 6:59, Surah Anaam 6:63, Surah Anaam 6:122, Surah Anaam 13:16, Surah Ibrahim 14:1, Surah Ibrahim 14:5, Surah Anbiya 21:87, Surah Noor 24:40, Surah Naml 27:63, Surah Ahzaab 33:43, Surah Faatir 35:20, Surah Zumar 43:6, Surah Hadeed 57:9, Surah Talaq 65:11.