Quantum

In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction. Behind this, one finds the fundamental notion that a physical property may be "quantized," referred to as "the hypothesis of quantization". This means that the magnitude can take on only certain discrete values.

A photon is a single quantum of (visible) light as well as all other forms of electromagnetic radiation and can be referred to as a "light quantum". The energy of an electron bound to an atom is quantized, which results in the stability of atoms, and hence of matter in general.

As incorporated into the theory of quantum mechanics, this is regarded by physicists as part of the fundamental framework for understanding and describing nature.

Etymology and discovery

The word "quantum" comes from the Latin "quantus", meaning "how much". "Quanta", short for "quanta of electricity" (electrons) was used in a 1902 article on the photoelectric effect by Philipp Lenard, who credited Hermann von Helmholtz for using the word in the area of electricity. However, the word quantum in general was well known before 1900. It was often used by physicians, such as in the term quantum satis. Both Helmholtz and Julius von Mayer were physicians as well as physicists. Helmholtz used "quantum" with reference to heat in his article on Mayer's work, and indeed, the word "quantum" can be found in the formulation of the first law of thermodynamics by Mayer in his letter dated July 24, 1841. Max Planck used "quanta" to mean "quanta of matter and electricity", gas, and heat. In 1905, in response to Planck's work and the experimental work of Lenard (who explained his results by using the term "quanta of electricity"), Albert Einstein suggested that radiation existed in spatially localized packets which he called "quanta of light" ("Lichtquanta").

Angelo

Angelo is an Italian masculine given name meaning "angel", or "messenger". Angelo is also an Italian surname that has many variations: Angeli (disambiguation), Angela (disambiguation), De Angelis, D'Angelo, Angelini, Angelino (disambiguation), Angelina (disambiguation), Angelucci, Angeloni, Angeletti (disambiguation).

People with the given name

Make

Make or MAKE may refer to:

See also

Insanity

Insanity, craziness or madness is a spectrum of behaviors characterized by certain abnormal mental or behavioral patterns. Insanity may manifest as violations of societal norms, including a person becoming a danger to themselves or others, though not all such acts are considered insanity; likewise, not all acts showing indifference toward societal norms are acts of insanity. In modern usage, insanity is most commonly encountered as an informal unscientific term denoting mental instability, or in the narrow legal context of the insanity defense. In the medical profession the term is now avoided in favor of diagnoses of specific mental disorders; the presence of delusions or hallucinations is broadly referred to as psychosis. When discussing mental illness in general terms, "psychopathology" is considered a preferred descriptor.

In English, the word "sane" derives from the Latin adjective sanus meaning "healthy". Juvenal's phrase mens sana in corpore sano is often translated to mean a "healthy mind in a healthy body". From this perspective, insanity can be considered as poor health of the mind, not necessarily of the brain as an organ (although that can affect mental health), but rather refers to defective function of mental processes such as reasoning. Another Latin phrase related to our current concept of sanity is "compos mentis" (lit. "sound of mind"), and a euphemistic term for insanity is "non compos mentis". In law, mens rea means having had criminal intent, or a guilty mind, when the act (actus reus) was committed.