Greek alphabetThe Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as well as consonants. In Archaic and early Classical times, the Greek alphabet existed in many local variants, but, by the end of the 4th century BC, the Euclidean alphabet, with 24 letters, ordered from alpha to omega, had become standard and it is this version that is still used for Greek writing today.
WavelengthIn physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, troughs, or zero crossings. Wavelength is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The inverse of the wavelength is called the spatial frequency.
Latin scriptThe Latin script, also known as the Roman script, is an alphabetic writing system based on the letters of the classical Latin alphabet, derived from a form of the Greek alphabet which was in use in the ancient Greek city of Cumae, in southern Italy (Magna Graecia). The Greek alphabet was adopted by the Etruscans, and subsequently their alphabet was adopted by the Romans. Several Latin-script alphabets exist, which differ in graphemes, collation and phonetic values from the classical Latin alphabet.
Phoenician alphabetThe Phoenician alphabet is an alphabet (more specifically, an abjad) known in modern times from the Canaanite and Aramaic inscriptions found across the Mediterranean region. The name comes from the Phoenician civilization. The Phoenician alphabet is also called the Early Linear script (in a Semitic context, not connected to Minoan writing systems), because it is an early development of the Proto- or Old Canaanite or Proto-Sinaitic script, into a linear, purely alphabetic script, also marking the transfer from a multi-directional writing system, where a variety of writing directions occurred, to a regulated horizontal, right-to-left script.
EpsilonEpsilon (ˈɛpsᵻlɒn, UKalsoɛpˈsaɪlən; uppercase Ε, lowercase ε or lunate ε; έψιλον) is the fifth letter of the Greek alphabet, corresponding phonetically to a mid front unrounded vowel e̞ or ɛ̝. In the system of Greek numerals it also has the value five. It was derived from the Phoenician letter He . Letters that arose from epsilon include the Roman E, Ë and Ɛ, and Cyrillic Е, È, Ё, Є and Э.
WaveIn physics, mathematics, engineering, and related fields, a wave is a propagating dynamic disturbance (change from equilibrium) of one or more quantities. Waves can be periodic, in which case those quantities oscillate repeatedly about an equilibrium (resting) value at some frequency. When the entire waveform moves in one direction, it is said to be a traveling wave; by contrast, a pair of superimposed periodic waves traveling in opposite directions makes a standing wave.
AstrophysicsAstrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline, James Keeler, said, Astrophysics "seeks to ascertain the nature of the heavenly bodies, rather than their positions or motions in space–what they are, rather than where they are." Among the subjects studied are the Sun (solar physics), other stars, galaxies, extrasolar planets, the interstellar medium and the cosmic microwave background.
RhoRho 'roʊ (uppercase Ρ, lowercase ρ or ; ρο or ρω) is the seventeenth letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician letter res . Its uppercase form uses the same glyph, Ρ, as the distinct Latin letter P; the two letters have different Unicode encodings. Rho is classed as a liquid consonant (together with Lambda and sometimes the nasals Mu and Nu), which has important implications for morphology.
Gordon FreemanGordon Freeman is the silent protagonist of the Half-Life video game series, created by Gabe Newell and designed by Newell and Marc Laidlaw of Valve. His first appearance is in Half-Life. Gordon Freeman is depicted as a bespectacled white man from Seattle, with brown hair and a signature goatee, who graduated from MIT with a PhD in theoretical physics. He was an employee at the fictional Black Mesa Research Facility. Controlled by the player, Gordon is often tasked with using a wide range of weapons and tools to fight alien creatures such as headcrabs, as well as Combine machines and soldiers.
PlanetA planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. The Solar System has at least eight planets: the terrestrial planets Mercury, Venus, Earth and Mars, and the giant planets Jupiter, Saturn, Uranus and Neptune.