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What is Light?

Light is electromagnetic radiation that is visible to the human eye. Illumination of 400–700 nm, between infrared (longer wavelengths) and ultraviolet (shorter wavelengths) (with shorter wavelengths). The term “light” in physics refers to electromagnetic radiation of any wavelength, visible or not. Light includes gamma rays, X-rays, microwaves, and radio waves. Light has four basic properties: intensity, propagation direction, and polarisation. Its speed in a vacuum, 299 792 458 m/s, is a basic constant. Visible light, like all electromagnetic radiation, is propagated by massless constituent particles called photons, which can be examined as both waves and particles. Optics is a major research topic in modern physics. The Sun is Earth’s principal light source. Fire has long been a source of illumination for people, from ancient campfires to modern kerosene lamps. Electric lights and electricity systems have effectively supplanted firelight.

In physics, the word “light” may point to electromagnetic radiation of any wavelength, whether seeable or not. Gamma rays, X-rays, microwaves and radio waves are likewise light. The primary effects of light are intensity, propagation approach, frequency or wavelength spectrum and polarization.

What Does The Term Light Signify?

Like all kinds of electromagnetic radiation, observable light multiplies by massless elementary particles called photons that describe the quanta of the electromagnetic field and can be interpreted as both waves and particles. The analysis of light, called optics, is an essential research region in modern physics.

The prior origin of genuine light on Earth is the Sun. Historically, another significant origin of light for humans has been fire, from antique campfires to current kerosene lamps. Electric lighting has substituted firelight with the growth of electric lights and control systems.

Classical Greece And Hellenism

In the fifth century BC, Empedocles proposed that everything comprised four components; fire, air, earth and water. He thought that Aphrodite assembled the human eye out of the four components and that she ignited the fire in the eye, which radiated out from the eye, causing sight to be possible. If this were correct, then one could see during the night just as well as during the daytime, so Empedocles hypothesized relations between rays from the eyes and rays from an origin such as a sun.

In about 300 BC, Euclid documented Optica, in which he investigated the properties of light. Euclid proposed that light transited in straight lines, and he defined the laws of reflection and examined them mathematically. He suspected that sight is the consequence of a ray from the eye, for he questions how one witnesses the stars instantly if one shuts one’s eyes and then opens them at nighttime. If the beam from the eye traverses infinitely fast, this is not a concern.

In 55 BC, Lucretius, a Roman who bore on the views of earlier Greek atomists, noted that “The light and warmth of the sun; these are comprised of minute atoms which, when they are plowed off, lose no time in shooting right across the interspace of air in the direction imparted by the shove.” Lucretius’s ideas were not commonly tolerated despite being identical to the latest particle theories. In his text Optics, Ptolemy (c. 2nd century) reported the refraction of light.

Classical India

In archaic India, the Hindu academies of Samkhya and Vaisheshika generated theories on light from around the early centuries AD. According to the Samkhya school, light is one of the five basic “nuanced” features (tanmatra); the gross details appear. The atomicity of these factors is not explicitly noted, and it seems that they were born to be constant. On the other hand, the Vaisheshika academy gives an atomic hypothesis of the material world on the non-atomic foundation of ether, space and time. The fundamental particles are those of soil (Prithvi), water (pani), fire (Agni) and air (Vayu). Light rays are assumed to be a stream of high velocity of Tejas (fire) atoms. Light particles can display various attributes relying on the Tejas atoms' speed and interpretations. The Vishnu Purana guides sunlight as “the seven rays of the sun”.

Descartes

René Descartes maintained that light was a mechanical possession of the luminous body, abandoning the “states” of Ibn al-Haytham and Witelo and the “species” of Bacon, Grosseteste and Kepler. In 1637 he issued a theory of the refraction of light that wrongly thought light transited faster in a denser medium than in a slightly dense medium. Descartes came to this decision by metaphor with the conduct of sound waves. Although Descartes was mistaken about the relative rates, he was right in thinking that light acted like a wave and concluding that light’s velocity could justify refraction in diverse media.

Use For Light On Earth

Sunlight supplies the energy that green plants utilize to assemble sugars, especially in starches, which discharge energy into the living things that digest them. This method of photosynthesis supplies virtually all the power-operated by living things. Some species of creatures develop their light, a technique called bioluminescence. For instance, fireflies employ light to discover mates, and vampire squid utilizes it to conceal from prey.

Light has significant spiritual implications associated with both angels and blessings. Angels frequently emerge as beings of light, and they use light’s electromagnetic energy when transiting to and from Earth and heaven. Miraculous circumstances, like apparitions, usually feature light emerging in supernatural forms.

Light is usually associated with knowledge. The term “enlighten” means to give details or understanding, particularly spiritual wisdom, to someone. When new creative concepts inspire people, they talk about a “light bulb” turning on for them. If they’ve earned a more reasonable stance on a problem, they say that they can glance at it “in a new light.” Spiritually, light stands for truth from the spiritual empire’s good side, confounding lies from the wrong side. Spiritually enlightened individuals know to select truth over duplicity in their daily lives.

Light in Religion

Christianity

Bible broadcasters like John W. Ritenbaugh see the existence of light as an analogy for truth, good and evil, wisdom and ignorance. In the first branch of the Bible, Elohim is defined as making light by fiat and witnessing it to be exemplary.

Buddhism

Buddhist scripture conveys multiple buddhas of light, including a Buddha of Boundless Light, a Buddha of Unrestrained Light, and Buddhas of Unopposed Light, Pristine Light, Incomparable Light, and Unending Light.

Hinduism

In Hinduism, Diwali — the festival of lights — marks the victory of light over darkness and good over evil. A mantra in Bṛhadāraṇyaka Upaniṣad (1.3.28) encourages God to ‘lead us unto Light’ from darkness.' The Rig Veda contains about two dozen hymns to the dawn and its deity, Ushas.

Zoroastrianism

Light is a core idea in Iranian mysticism. The primary sources of this thought are in the Zoroastrian ideas, which represent The Supreme God Ahura Mazda as the origin of light. This essential feature manifests in diverse schools of introspection in Persian mysticism and philosophy.


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