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Lambda Cdm Model
The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a Parameter#Modelization, parameterization of the Big Bang physical cosmology, cosmological model in which the universe contains three major components: first, a cosmological constant denoted by Lambda (Greek alphabet, Greek Λ) associated with dark energy; second, the postulated cold dark matter (abbreviated CDM); and third, ordinary matter. It is frequently referred to as the standard model of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos: * the existence and structure of the cosmic microwave background * the Observable universe#Large-scale structure, large-scale structure in the distribution of galaxies * the observed abundance of the chemical elements, abundances of Big Bang nucleosynthesis, hydrogen (including deuterium), helium, and lithium * the accelerating expansion of the universe observed in the light from distant galaxies and ...
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Parameter
A parameter (), generally, is any characteristic that can help in defining or classifying a particular system A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purp ... (meaning an event, project, object, situation, etc.). That is, a parameter is an element of a system that is useful, or critical, when identifying the system, or when evaluating its performance, status, condition, etc. ''Parameter'' has more specific meanings within various disciplines, including mathematics Mathematics (from Greek: ) includes the study of such topics as numbers (arithmetic and number theory), formulas and related structures (algebra), shapes and spaces in which they are contained (geometry), and quantities and their changes (cal ..., computer programming Computer programming is the process of ...
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Quintessence (physics)
In physics Physics is the natural science that studies matter, its Elementary particle, fundamental constituents, its Motion (physics), motion and behavior through Spacetime, space and time, and the related entities of energy and force. "Physical scie ..., quintessence is a hypothetical A hypothesis (plural hypotheses) is a proposed explanation An explanation is a set of statements usually constructed to describe a set of facts which clarifies the causes, context Context may refer to: * Context (language use), the rel ... form of dark energy In physical cosmology Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the unive ..., more precisely a scalar field In mathematics Mathematics (from Greek: ) includes the study of such topics as numbers (arithmetic and number theory), formulas ...
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Type Ia Supernova
A type Ia supernova (read: "type one-A") is a type of supernova A supernova ( plural: supernovae or supernovas, abbreviations: SN and SNe) is a powerful and luminous stellar explosion. This transient astronomical event occurs during the last stellar evolution, evolutionary stages of a massive star or when a ... that occurs in binary system A binary system is a system of two astronomical bodies which are close enough that their gravitational attraction causes them to orbit each other around a barycenter ''(also see Barycenter#Gallery, animated examples)''. More restrictive definiti ...s (two star A star is an astronomical object consisting of a luminous spheroid of plasma Plasma or plasm may refer to: Science * Plasma (physics), one of the four fundamental states of matter * Plasma (mineral) or heliotrope, a mineral aggregate * Quark ...s orbiting one another) in which one of the stars is a white dwarf A white dwarf, also called a degenerate dwarf, is a ...
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Dark Energy Survey
The Dark Energy Survey (DES) is an astronomical survey designed to constrain the properties of dark energy. It uses images taken in the near-ultraviolet, Visible spectrum, visible, and near-infrared to measure the expansion of the Universe using Type Ia supernovae, baryon acoustic oscillations, the number of Galaxy groups and clusters, galaxy clusters, and weak gravitational lensing. The collaboration is composed of research institutions and universities from the United States,DES Collaboration Page
DES Collaborators.
Australia, Brazil,DES-Brazil
, DES-Brazil Consortium.
the United Kingdom, Germany, Spain, and Switzerland. The collaboration is divided into several scientific working groups. Th ...
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Stress–energy Tensor
The stress–energy tensor, sometimes called the stress–energy–momentum tensor or the energy–momentum tensor, is a tensor In mathematics Mathematics (from Greek: ) includes the study of such topics as numbers ( and ), formulas and related structures (), shapes and spaces in which they are contained (), and quantities and their changes ( and ). There is no ... physical quantity A physical quantity is a physical property of a material or system that can be Quantification (science), quantified by measurement. A physical quantity can be expressed as a ''value'', which is the algebraic multiplication of a ''numerical value'' ... that describes the density The density (more precisely, the volumetric mass density; also known as specific mass), of a substance is its per unit . The symbol most often used for density is ''ρ'' (the lower case Greek letter ), although the Latin letter ''D'' can also ... and flux of \mathbf(\mathbf) with the unit normal vecto ...
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Doppler Shift
The Doppler effect or Doppler shift (or simply Doppler, when in context) is the change in frequency Frequency is the number of occurrences of a repeating event per unit of time A unit of time is any particular time Time is the indefinite continued sequence, progress of existence and event (philosophy), events that occur in an apparen ... of a wave In physics Physics is the that studies , its , its and behavior through , and the related entities of and . "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular su ... in relation to an observer An observer is one who engages in observation or in watching an experiment. Observer may also refer to: Computer science and information theory * In information theory Information theory is the scientific study of the quantification, storage ... who is moving relative to the wave source. It is named after the Austria Austria (, ...
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Red Shift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in frequency and energy, is known as a negative redshift, or blueshift. The terms derive from the colours red and blue which form the extremes of the Visible spectrum, visible light spectrum. In astronomy and cosmology, the three main causes of electromagnetic redshift are # The radiation travels between objects which are moving apart ("Special relativity, relativistic" redshift, an example of the relativistic Doppler effect) #The radiation travels towards an object in a weaker gravitational potential, i.e. towards an object in less strongly Curved space, curved (flatter) spacetime (gravitational redshift) #The radiation travels through Expansion of the universe, expanding space (cosmological redshift). The observation that all sufficiently di ...
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Homogeneity (physics)
In physics, a homogeneous material or system has the same properties at every point; it is uniform without irregularities. (accessed November 16, 2009). Tanton, James. "homogeneous." Encyclopedia of Mathematics. New York: Facts On File, Inc., 2005. Science Online. Facts On File, Inc. "A polynomial in several variables p(x,y,z,…) is called homogeneous ..more generally, a function of several variables f(x,y,z,…) is homogeneous ..Identifying homogeneous functions can be helpful in solving differential equations ndany formula that represents the mean of a set of numbers is required to be homogeneous. In physics, the term homogeneous describes a substance or an object whose properties do not vary with position. For example, an object of uniform density is sometimes described as homogeneous." James. homogeneous (math). (accessed: 2009-11-16) A uniform electric field An electric field (sometimes E-field) is the physical field that surrounds electrically-charged particle In ...
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Isotropy
Isotropy is uniformity in all orientations; it is derived from the Greek ''isos'' (ἴσος, "equal") and ''tropos'' (τρόπος, "way"). Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix ''an'', hence ''anisotropy Anisotropy () is the property of a material which allows it to change or assume different properties in different directions as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physic ...''. ''Anisotropy'' is also used to describe situations where properties vary systematically, dependent on direction. Isotropic radiation has the same intensity regardless of the direction of measurement Measurement is the quantification (science), quantification of variable and attribute (research), attributes of an object or event, which can be used to compare with other objects or events. The scope and application of measurement are dependen ..., ...
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Cosmological Principle
#REDIRECT Cosmological principle In modern physical cosmology Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the ...
{{R from other capitalisation ...
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Pavel Kroupa
Pavel Kroupa (born 24 September 1963 in Jindřichův Hradec, Czechoslovakia) is a Czech-Australian astrophysicist and professor at the University of Bonn. Biography and career After the 1968 failure of Prague spring, Kroupa's family fled from Czechoslovakia losing all possessions; as a consequence Kroupa grew up in Germany and South Africa. He acquired in 1983 his Abitur final exams in Göttingen and afterwards studied physics at The University of Western Australia in Perth, Western Australia, Perth. In 1988 he won the Isaac Newton scholarship at the University of Cambridge and in 1992 the senior W. W. Rouse Ball, Rouse Ball research scholarship at Trinity College, Cambridge and attained a doctorate in England in 1992 with a dissertation on the distribution of low mass stars in the Milky Way. Afterwards Kroupa worked until 2000 in astronomical research groups at Heidelberg University and at the Max Planck Institute for Astronomy, before he went to the University of Kiel and earne ...
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