An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A branch of philosophy that investigates the possibility, origins, nature, methods, and limits of human knowledge.

From Gk. episteme "knowledge," from Ionic Gk. epistasthai "to understand," literally "overstand," from → epi- "over, near" + histasthai "to stand;" cognate with Pers. istâdan "to stand," → standard; PIE base *sta- "to stand."

From šenaxt, → knowledge, + -šenâsi, → -logy.

1) To have actual being or reality; to be.
2) To have life; to live.

M.E., from O.Fr. exister, ultimately from pr.p. of L. existere/exsistere "to stand forth, appear; to exist, be;" from → ex- + sistere "cause to stand," from PIE *sta-, cf. Pers. istâdan "to stand," → state.

Hastumand budan, from Mid.Pers. hastumand "existing, existent," from hast, ast 'is" (infinitive hastan, astan); O.Pers. astiy; Av. asti "is;" O.Pers./Av. root ah- "to be;" cf. Skt. as-; Gk. esti; L. est; PIE *es-, + euphonic -u-, + -mand possession suffix, → -ist, + budan "to be," to become;" Mid.Pers. butan "to be ,become," from O.Pers./Av. bav- "to be; become, take place," Av. buta- perf. ptcpl. pass., bavaiti "becomes," Skt. bhavati "becomes, happens," bhavah "becoming; condition, state," PIE *bheu- "to be, come into being, become;" cf. Gk. phu- "become," phuein "to bring forth, make grow," L. fui "I was" (perf. tense of esse), futurus "that is to be, future," Ger. present first and second person sing. bin, bist, E. to be, O.Ir. bi'u "I am," Lith. bu'ti "to be," Rus. byt' "to be."

Math.: The fact that at least one → solution exists for a given → problem.

→ exist; → -ence.

Math: The question of whether a → solution to a given → problem exists.

→ existence; → problem.

Math.: An → argument that establishes an → existence theorem.

→ existence; → proof.

Math: A theorem that asserts the existence of at least one object, such as the → solution to a → problem or → equation.

→ existence; → theorem.

Existing; having existence.

→ exist.

1) Of or relating to → existence, especially  human existence.
2) Philo.:  Pertaining to what exists, and is thus known by experience rather  than reason; empirical as opposed to theoretical.
3) Logic: Denoting or relating to a → formula or → proposition asserting the existence of at least one object fulfilling a given condition; containing an → existential quantifier.
4) Of or relating to → existentialism (Dictionary.com).

From L.L. existentialis, → existence, → -al.

Hastiyâl, from hasti, → existence, + -al a suffix of attributes forming adjectives that often become nouns, in this case preferred to -i because hasti ends in -i, → -al.

A symbol of → predicate logic which expresses that the statements within its scope are → true for at least one instance of something. The symbol ∃ is used as the existential quantifier. Existential quantifiers are normally used in logic in → conjunction with → predicate symbols, which say something about a → variable or → constant, in this case the variable being quantified (→ quantify, → quantification).

→ existential; → quantifier.

A philosophical attitude associated especially with Heidegger, Jaspers, Marcel, and  Sartre, and opposed to → rationalism and  → empiricism, that stresses the individual's  unique position as a self-determining agent responsible for the authenticity of his or  her choices (Dictionary.com).

→ existential; → -ism.

An advocate of → existentialism.

→ existential; → -ist.

A set of distributions which have the same general mathematical → formula.

→ family; → distribution.

The statistical distribution of → fermions over the energy states for a system in → thermodynamic equilibrium. In other words, the probability that a given energy level be occupied by a fermion.

→ fermi, → Dirac function; → statistics.

same as → focal length.

→ focal; → distance.

The distance from the center of a galaxy.

→ galactocentric; → distance.

A theoretical frequency distribution for a set of variable data, usually represented by a bell-shaped curve with a mean at the center of the curve and tail widths proportional to the standard deviation of the data about the mean.

→ Gaussian; → distribution.

Of, relating to, or subject to the theory of → general relativity.

→ general; → relativistic.

A field of science that is concerned with the relative abundance, distribution, and the movement of → chemical elements in the → Earth's crust or other → solar system objects.

→ geo-; → chemistry.

A quantum mechanical phenomenon where the resistance of certain materials drops dramatically upon application of a magnetic field in certain structures composed of alternating layers of magnetic and nonmagnetic metals. The basis of the GMR is the dependence of the electrical resistivity of electrons in a magnetic metal on the direction of the electron spin, either parallel or anti-parallel to the magnetic moment of the layers. The 2007 Nobel Prize in physics was awarded to the French physicist Albert Fert (1938-) and German physicist Peter Grünberg (1939-) for the discovery of GMR.

→ giant; magneto- combining form of → magnet; → resistance.

The probability distribution of the various possible states of a certain → quasi-closed subsystem.

→ Gibbs free energy; → canonical; → distribution.