Refimprove date October 2010 Inducedradioactivity occurs when a previously stable material has been made radioactive by exposure to specific radiation . Most radioactivity does not induce other material to become radioactive. Neutron activation is the main form of inducedradioactivity, which happens when free neutron s are captured by nuclei. This new heavier isotope can be stable or unstable radioactive depending on the chemical element involved. Because free neutrons disintegrate within minutes outside of an atomic Atomic nucleus nucleus , neutron radiation can be obtained only from nuclear disintegration s, nuclear reaction s, and high energy reactions such as in cosmic radiation showers or particle accelerator collisions . Neutrons that have been slowed down through a neutron moderator thermal neutron s are more likely to be captured by nuclei than fast neutrons. A less common form involves removing a neutron via photodisintegration . In this reaction, a high energy photon gamma ray strikes a nucleus with an energy greater than the binding energy of the atom , releasing a neutron. This reaction has a minimum cutoff of 2 Electronvolt MeV for hydrogen and around 10 MeV for most ... and thus cannot induce radioactivity in the food. ref Caesium 137 emits gammas at 662 keV while cobalt 60 emits gammas at 1.2 and 1.3 MeV. ref Some inducedradioactivity is produced by background ... places on Earth , the amount of inducedradioactivity in a single location is usually very small. The conditions inside certain types of nuclear reactor s with high neutron flux can cause inducedradioactivity. The components in those reactors may become highly radioactive from the radiation to which they are exposed. Inducedradioactivity increases the amount of nuclear waste that must eventually ... irradiation DEFAULTSORT InducedRadioactivity Category Radioactive waste Category Radioactivity Category .... See also Neutron activation Radioactive decay Radioactivity Slow neutron Notes references External ... more details
album Radioactivity album Radio Activity . The song was released as a single in most European territories .... Radioactivity has remained a regular part of Kraftwerk s live sets over the years. On its original ... . While the original does not offer a value judgement on the safety of radioactivity, the 1991 ... theme, remaking the central lyrical hook as stop radioactivity and also referring to contaminated ... Single See Wikipedia WikiProject Songs Name Radioactivity Cover Fatboy Slim Radioactivity.jpg Artist Fatboy Slim from Album Late Night Tales Fatboy Slim A side Radioactivity B side Everything Is Everything ... Champion Sound song Champion Sound br 2006 This single Radioactivity br 2007 Next single Fatboy Slim covered Radioactivity on his compilation album Late Night Tales Fatboy Slim . The song was released as a limited edition 7 single. Track listing Radioactivity Fatboy Slim Everything Is Everything Bootsy Collins Kraftwerk Fatboy Slim Fatboy Slim singles DEFAULTSORT Radioactivity Song Category Kraftwerk ... 1970s single stub fr Radioactivity chanson it Radioactivity pt Radioaktivit t ... more details
Environmental radioactivity is produced by radioactive materials in the human Ecosystem environment ... Radioactivity is present everywhere, and has been since the formation of the earth. According to the IAEA ... at the Nevada Test Site from 1951 1962. The additional radioactivity in the biosphere caused by human activity due to the releases of man made radioactivity and of Naturally Occurring Radioactive ... and the transfer to humans of deposited radioactivity Just because a radioisotope lands on the surface ... H la claims in his textbook Radioactivity, Ionizing Radiation and Nuclear Energy full date November ... of the soil s radioactivity Bq g sup 1 sup to that of the soil water Bq ml sup 1 sup . If the radioactivity is tightly bonded to by the minerals in the soil then less radioactivity can be absorbed by crops ... Trinityglassactivity.png right 400px thumb Levels of radioactivity in the Trinity glass from two ... made radioactivity is a nuclear weapons test. The glassy trinitite formed by the first atom bomb ... Cooper, P.M. Rosenberg and M.E. Kitto, Journal of Environmental Radioactivity , 2006, 85 , 103 120 ... of radioactivity for these isotopes is highest where the neutron dose to the soil was larger. Some ... increased the radioactivity specific activity of carbon, whereas the use of fossil fuels has decreased ... fuel cycle . A paper has been written on the radioactivity found in oyster s found in the Irish ..., Z. Vav kov and T. Van k, Journal of Environmental Radioactivity , 2006, 88 , 236 250 ref The caesium ... of the shallow root s of the grass, hence the level of radioactivity in the grass will be lowered ... to the ground in Japan source M. Yamamoto et al. , Journal of Environmental Radioactivity , 2006 ... Radioactivity , 2006, 86 , 110 131 ref Uranium lead dating main Uranium lead dating Uranium lead dating ... Society of America Bulletin 113 7 , 825 836. Further reading Radioactivity, Ionizing Radiation and Nuclear ... Radioactivity Category Astrophysics Category Environmental isotopes Category Geochemistry ... more details
about radioactivity as a tool in life science the effect of radiation on living organisms Radiation poisoning organisms which harness radiation Radiotrophic fungus the bacterium highly resistant to radiation Deinococcus radiodurans Radioactivity can be used in life sciences as a radiolabel to visualise components or target molecules in a biological system. Some radionuclei are synthesised in particle accelerator s and have short Half life half lives , giving them high maximum theoretical specific activities. This lowers the detection time compared to radionuclei with longer half lives, such as carbon 14. In some applications they have been substituted by fluorescent dye s. Examples of radionuclei Tritium hydrogen 3 is a very low energy emitter that can be used to label protein s, nucleic acid s, drugs and toxins, but requires a tritium specific film or a tritium specific phosphor screen . In a liquid scintillation assay LSA , the efficiency is 20 50 , depending on the scintillation cocktail used Citation needed date December 2009 . The maximum theoretical specific activity of tritium is 28.8 Curie Ci Mole unit mmol 1.066 PBq mol . Citation needed date December 2009 However, there is often more than one tritium atom per molecule for example, tritiated Uridine triphosphate UTP is sold by most suppliers with carbons 5 and 6 each bonded to a tritium atom. C 14, S 35 and P 33 have similar ... acids intact. Radioactivity concentration A vial of radiolabel has a total activity . Taking ... the radioactivity concentration and depends on the radionuclei s half life. If every molecule were ... use of Fluorescence in the life sciences fluorescence in the past three decades radioactivity ... , whereas with radioactivity two isotopes can be used tritium and a low energy isotope, e.g. Phosphorus ... DEFAULTSORT Radioactivity In The Life Sciences Category Radiation health effects Category Biology Category Radioactivity ... more details
particulate radioactivity APR . In more recent times they may also be used to monitor people in their homes for the presence of manmade radioactivity. These monitors can be used to trigger alarms ..., ISBN 0 87079 005 6 Eisenbud, Environmental Radioactivity , Academic 1973 , p. 449 Assessment of Airborne Radioactivity , International Atomic Energy Agency 1967 , p. 24 ref The particulate radioactive ... radioactivity, due to the much larger total volume of air passing through the filter medium ... hand, monitoring with CPAMs provides nearly real time airborne radioactivity level indication ... 2004, Specification and Performance of On Site Instrumentation for Continuously Monitoring Radioactivity ... is difficult a more reliable measurement of the total radioactivity released over some time ... 10CFR50 Appendix A ref states Criterion 64 Monitoring radioactivity releases. Means shall be provided ... of loss of coolant accident fluids, effluent discharge paths , and the plant environs for radioactivity ... Radioactivity in Solid Wastes and Releases of Radioactive Materials in Liquid and Gaseous Effluents ... Occupational Airborne Radioactivity Monitoring Instrumentation ref . A difficulty with this is that, unless ... of Airborne Radioactivity Area , 1201, 1204, 1501, 1502, 2103. CPAM applications process monitoring ... levels of airborne radioactivity could be brought into the control room by its HVAC system the CPAM monitors this air and is intended to detect high concentrations of radioactivity and shut down ... the airborne particulate radioactivity in the reactor containment structure is an acceptable ... the rate at which the detector is responding to the radioactivity deposited on the filter medium. There are two .... The countrate that results from deposited radioactivity is called the net countrate, and is obtained .... Also, these are integrating devices, meaning that some finite time is required to accumulate radioactivity ... source term airborne radioactivity emission rate , it is not realistic to hold the concentration ... more details
Unreferenced stub auto yes date December 2009 Induced consumption is a term used to describe consumption expenditure by households on goods and services which varies with income. Such consumption is considered induced by income when expenditure on these consumables varies as income changes. For example, expenditure on a consumable that is considered a normal good would be considered to be induced . Induced consumption is, by definition, the opposite of autonomous consumption . Some Ways in Which Induced Consumption Occurs Conspicuous consumption When people consume things to display a higher status than others. Artificial consumption When people consume things because they were introduced to them through various forms of media. See also Consumption economics Consumption function DEFAULTSORT Induced Consumption Category Consumer theory Econ stub ... more details
Induced menopause is menopause induced by medical treatment, intentionally or unintentionally. Some causes of induced menopause can include chemotherapy , radiotherapy and oophorectomy . ref cite web url http www.hon.ch Dossier MotherChild gynae problems menopausal.html title Gynaecologic Problems Menopausal Problems publisher Health on the Net Foundation accessdate 2012 02 22 ref References reflist med stub Category Menopause ... more details
In mathematics , an induced character is the character mathematics character of the group representation representation V of a finite group G induced representation induced from a representation W of a subgroup H G . Someone should generalize this article. Taku More generally, there is also a notion of induction of a class function induction math operatorname Ind f math of a class function f on H given by the formula math operatorname Ind f s frac 1 H sum t in G, t 1 st in H f t 1 st . math If f is a character of the representation W of H , then this formula for math operatorname Ind f math calculates the character of the induced representation V of G . ref Serre, 7.2. Proposition 20. ref The basic result is Brauer s theorem on induced characters . It states that a character on G is a linear combination with integer coefficients of characters induced from elementary group elementary subgroup s. References reflist J.P. Serre, Linear representations of finite groups . Graduate Texts in Mathematics, vol. 42, Springer Verlag, New York, Heidelberg, Berlin, 1977, Category Group theory algebra stub ... more details
Induced movement or induced motion is an illusion of visual perception in which a stationary or a moving object appears to move or to move differently because of other moving objects nearby in the visual field . The object affected by the illusion is called the target , and the other moving objects are called the background or the context Duncker, 1929 . Induced movement with stationary target A stationary object appears to move in the opposite direction to the background. For example, the moon on a cloudy, windy night appears to be racing through the sky opposite to the direction of the clouds, even though the moon is essentially stationary in the sky. For an illustration, see http psychlab1.hanover.edu Classes Sensation inducedInduced movement with a moving target A moving object appears to be moving faster when it is moving in the opposite direction to the background it appears to be moving slower when it is moving in the same direction as the background. ref For an illustration, see http www.uni bielefeld.de en psychologie ae Ae01 forschung indumo.html ref Drug induced Movement Disorders Low CNS penetration is the result from drug induced movement disorders, which has occasionally been associated with the use of domperidone Hae Won Shin et al., 2009 . Therefore, there is close monitoring of patients if treatment with peripheral dopamine antagonists are used Hae Won Shin et al., 2009 . History of induced movement Induced movement was reported by Ptolemy ca. 90 ca. 168 AD see Smith, 1996 . It was researched extensively by Duncker 1929 . See also Autokinetic effect Motion aftereffect Motion induced blindness Motion perception References reflist Duncker, K. 1929 . ber induzierte Bewegung Ein Beitrag zur Theorie optisch wahrgenommener Bewegung . Psychologische Forschung, 12, 180 259. Smith, A. M. 1996 . Ptolemy s theory of visual perception An English translation of the Optics ... 2009 . Levosulpiride induced movement disorders . Movement Disorders ,24 15 , pg. 2249 2253 . User ... more details
Image Snakeinthebox.svg thumb An induced path of length four in a hypercube graph cube . Finding the longest induced path in a hypercube is known as the snake in the box problem. In the mathematics mathematical area of graph theory , an induced path in an undirected graph G is a path graph theory path that is an induced subgraph of G . That is, it is a sequence of vertices in G such that each two adjacent ... are not connected by any edge in G . An induced path is sometimes called a snake , and the problem of finding long induced paths in hypercube graph s is known as the snake in the box problem. Similarly, an induced cycle is a cycle graph cycle that is an induced subgraph of G induced cycles ... of a hole. The length of the longest induced path in a graph has sometimes been called the detour number of the graph. ref harvtxt Buckley Harary 1988 . ref The induced path number of a graph G is the smallest number of induced paths into which the vertices of the graph may be partitioned, ref harvtxt ... number of induced paths that together include all vertices of G . ref harvtxt Barioli Fallat ... must be an induced cycle as any chord could be used to produce a shorter cycle for similar reasons the odd girth of a graph is also the length of its shortest odd induced cycle. Example The illustration shows a cube, a graph with eight vertices and twelve edges, and an induced path of length four in this graph. A straightforward case analysis shows that there can be no longer induced path in the cube, although it has an induced cycle of length six. The problem of finding the longest induced path or cycle in a hypercube, first posed by harvtxt Kautz 1958 , is known as the snake in the box ... of the induced paths or cycles of the graphs in the family. Trivially, the connected graphs with no induced path of length two are the complete graph s, and the connected graphs with no induced cycle are the tree graph theory tree s. A triangle free graph is a graph with no induced cycle of length ... more details
Induced polarization IP is a geophysical imaging technique used to identify subsurface materials, such as ore . The method is similar to electrical resistivity tomography , in that an electric current is Electromagnetic induction induced into the subsurface through two electrode s, and voltage is monitored through two other electrodes. Time domain IP methods measure the voltage decay or chargeability over a specified time interval after the induced voltage is removed. The Antiderivative integrated voltage is used as the measurement. Frequency domain IP methods see Spectral induced polarisation Spectral Induced Polarisation use alternating current s AC to induce electric charges in the subsurface, and the apparent resistivity is measured at different AC frequencies. References cite book last Kearey first Philip coauthors Michael Brooks title An Introduction to Geophysical Exploration year 1991 edition Second edition publisher Blackwell Science isbn 0 632 02923 4 External links Remove this commercial link if a better non commercial link e.g., Gov t or academic is found http www.l gm.de English Resistivity Meters resistivity meters.html Example IP equipment and image results Category Geophysical imaging Geology stub Geophysics stub ru ... more details
Induced innovation is a macroeconomic hypothesis first proposed in 1932 in literature 1932 by John Hicks J.R. Hicks in his work The Theory of Wages . He proposed that a change in the relative prices of the factors of production is itself a spur to invention , and to invention of a particular kind&mdash directed to economizing the use of a factor which has become relatively expensive. Considerable literature has been produced on this hypothesis, which is often presented in terms of the effects of wage increases as an encouragement to labor saving innovation. The hypothesis has also been applied to viewing increases in energy costs as a motivation for a more rapid improvement in energy efficiency of goods than would normally occur. See also Creativity techniques International Innovation Index References The Theory of Wages , J. R. Hicks, Macmillan, London , 1932. DEFAULTSORT Induced Innovation Category Macroeconomics macroeconomics stub ... more details
In mathematics , an induced homomorphism is a structure preserving map between a pair of objects that is derived in a canonical way from another map between another pair of objects. A particularly important case arises in algebraic topology , where any continuous function between two Pointed space pointed topological space s induces a group homomorphism between the fundamental group s of the two spaces. Likewise, the same continuous map induces a group homomorphism between the respective homotopy group s, the respective homology group s and a homomorphism going in the opposite direction between the corresponding cohomology group s. A homomorphism is a structure preserving map between two mathematical objects of the same type a group homomorphism , for instance, is a map between two Group mathematics groups such that the image of the product of any two group items is the same as the product of their images, while a graph homomorphism is a map from the vertices of one undirected graph to the vertices of another such that any edge of the first graph is mapped to an edge of the second. Families of objects, and maps between them, are generally formalized as objects and morphisms in a category theory category by convention, the morphisms in categories are depicted as arrows in diagrams. In many of the important categories of mathematics, the morphisms are called homomorphisms. In category theory, a functor is itself a structure preserving map, between categories it must map objects ... induced from &fnof by F . For example, let X and Y be topological spaces with fundamental groups X ... is called the induced homomorphism of . The construction of a fundamental group for each topological space, and of an induced homomorphism of fundamental groups for each continuous function ... group Functoriality for more on this type of induced homomorphism. See also Induced homomorphism algebraic topology Induced homomorphism fundamental group References unref date June 2008 Category ... more details
Earthquakes Induced seismicity refers to typically minor earthquake s and tremors that are caused by human activity that alters the stresses and strains on the Earth s Crust geology crust . Most induced ... of ways in which induced seismicity has been seen to occur. Reservoirs The mass of water ... can trigger earthquakes. Reservoir induced seismic events can be relatively large compared to other forms of induced seismicity. The first case of reservoir induced seismicity occurred in 1932 in Algeria s Oued Fodda Oued Fodda Dam . Unfortunately, understanding of reservoir induced seismic activity ... explanation for the seismic activity. ref http internationalrivers.org de node 1477 ref Induced seismicity ... dams. Once the reservoirs are filled, induced seismicity could occur immediately or with a small ... en node 1477 Reservoir Induced Seismicity ref 180 people died and 1,500 were left ..., P. 1998 http www.springerlink.com content vu4u79euw6w01unx Reservoir induced Seismicity in China ... egsp.lyellcollection.org cgi content abstract 5 1 405 Mining induced seismicity in UK coalfields identified ... induced seismicity oil&gas ref ref Van Eijsa, R.M.H.E, Muldersa, F.M.M, Nepveua, M, Kenterb, C.J ... 5e4d2f903fb0995f9c0b05c60b84759b Correlation between hydrocarbon reservoir properties and induced ..., are known to be associated with induced seismicity. EGS involves pumping fluids at pressure to enhance ... Peak and the Geysers U.S. , Landau Germany ,and Paralana and Cooper Basin Australia . Induced seismicity ... Geothermal Field ref The test site at Basel, Switzerland, has been shut down due to induced seismic ... Dealing with Induced Seismicity journal IEA Open Journal volume 48 issue 7 date February 2007 .... With appropriate management, the number and magnitude of induced seismic events can be decreased ... Induced seismicity in Basel led to suspension of its HDR project. A seismic hazard evaluation was then conducted ... of induced seismicity journal Engineering Geology volume 10 issue 2 4 pages 85 98 issn 00137952 ... more details
In topology and related areas of mathematics , an induced topology on a topological space is a topology which is optimal for some Function mathematics function from to this topological space. Definition Let math X 0, X 1 math be sets, math f X 0 to X 1 math . If math tau 0 math is a topology on math X 0 math , then a topology induced on math X 1 math by math f math is math U 1 subseteq X 1 f 1 U 1 in tau 0 math . If math tau 1 math is a topology on math X 1 math , then a topology induced on math X 0 math by math f math is math f 1 U 1 U 1 in tau 1 math . The easy way to remember the definitions above is to notice that finding an inverse image is used in both. This is because inverse image preserves union set theory union and intersection set theory intersection . Finding a direct image does not preserve intersection in general. Here is an example where this becomes a hurdle. Consider a set math X 0 2, 1, 1, 2 math with a topology math 2, 1 , 1, 2 math , a set math X 1 1, 0, 1 math and a function math f X 0 to X 1 math such that math f 2 1, f 1 0, f 1 0, f 2 1 math . A set of subsets math tau 1 f U 0 U 0 in tau 0 math is not a topology, because math 1, 0 , 0, 1 subseteq tau 1 math but math 1, 0 cap 0, 1 notin tau 1 math . Properties A topology math tau 1 math induced on math X 1 math by math f math is the finest topology such that math f math is Continuity topology continuous math X 0, tau 0 to X 1, tau 1 math . A topology math tau 0 math induced on math X 0 math by math f math is the coarsest topology such that math f math is continuous math X 0, tau 0 to X 1, tau 1 math . Examples In particular, if math f math is an inclusion map , then math tau 0 math is a subspace topology . References cite book last1 Hu first1 Sze Tsen authorlink1 last2 first2 authorlink2 title Elements of general topology url edition series volume year 1969 publisher Holden Day location isbn id Category Topology Category General topology topology stub ... more details
In mathematics , and in particular group representation theory, the induced representation is one of the major general operations for passing from a representation of a subgroup H to a representation of the whole ... cases the action of G on the cosets G H by permutation, which is the case of the induced representation ... representation of G . Therefore induced representations are rich objects, in the sense that they include ... maps from Res to . Here Res stands for restricted representation , and Ind for induced representation ... the decomposition of the induced representation we can do calculations on the side of H , which ... , given by h Tr h , then the character of the induced representation is given by math psi g sum ... suggests that induced representation can in this case be defined by means of the adjunction. That s not the only ... hoc in its start. One can therefore make the reciprocity theorem the way to define the induced .... The induced representation Ind should be realized as a space of functions on G transforming ... about left and right actions . This approach allows the induced representation to be a kind of free ... writing down the character group theory character trace of the induced representation, in terms ... set of representatives in G of the cosets in G H . The induced representation math operatorname Ind ... the induced representation G acts on W as follows math g cdot sum i 1 n x i v i sum i 1 n x j i pi h ... analytic construction of the induced representation. Let , V be a continuous function continuous ... measure . The group G acts on the induced representation space by right translation, that is, g ... bundle is the induced representation. In the case of unitary representation s of locally compact ... of imprimitivity . Examples For any group, the induced representation of the trivial representation of the trivial subgroup is the right regular representation . More generally the induced representation ... of that subgroup. An induced representation of a one dimensional representation is called a monomial ... more details
A barbiturate induced coma , or barb coma , is a temporary coma a deep state of unconsciousness brought on by a controlled dose of a barbiturate drug, usually pentobarbital or thiopental . Barbiturate comas are used to protect the brain during major neurosurgery , and as a last line of treatment in certain cases of status epilepticus that have not responded to other treatments. Barbiturates reduce the metabolic rate of brain tissue, as well as the cerebral blood flow . With these reductions, the blood vessel s in the brain narrow, decreasing the amount of volume occupied by the brain, and hence the intracranial pressure . The hope is that, with the swelling relieved, the pressure decreases and some or all brain damage may be averted. Several studies have supported this theory by showing reduced mortality when treating refractory intracranial hypertension with a barbiturate coma. ref cite journal date Jun July 2000 title Use of barbiturates in the control of intracranial hypertension journal Journal of Neurotrauma publisher The Brain Trauma Foundation volume 17 issue 6 7 pages 527 30 pmid 10937896 doi 10.1089 neu.2000.17.527 ref ref cite journal title The efficacy of barbiturate coma in the management of uncontrolled intracranial hypertension following neurosurgical trauma journal Journal of Neurotrauma date 1994 06 01 first MW last Lee coauthors Deppe SA, Sipperly ME, Barrette RR, Thompson DR. volume 11 issue 3 pages 325 31 pmid 7996586 doi 10.1089 neu.1994.11.325 ref ref cite journal title The effect of high dose barbiturate decompression after severe head injury A controlled ... that barbiturate induced coma can reduce intracranial hypertension but does not necessarily prevent ... benefit of induced coma in diverse conditions such as neurosurgical operations, head trauma , ref ... electrical activity in the brain. When barbiturates are given to brain injured patients for induced ... are withdrawn gradually and the patient regains consciousness. Induced coma was used in the treatment ... more details
Incomplete date February 2009 Refimprove date February 2008 Induced demand , or latent demand , is the phenomenon that after supply increases, more of a good is consumed. This is entirely consistent with the economic theory of supply and demand however, this idea has become important in the debate over the expansion of transport ation systems, and is often used as an argument against widening roads, such as major commuter roads. It is considered by some to be a contributing factor to urban sprawl . Effect in transportation systems Latent demand has been recognised by road traffic professionals for many decades. J. J. Leeming , a British road traffic engineer and county surveyor between 1924 and 1964 ..., it also constitutes induced travel, usually because people travel farther to get to work as a result ... loop. Eventually, the induced demand may cause road capacity to be reached again . Induced demand ... in car ownership and economic activity, and does not take into account traffic induced by the presence ... Planning author Litman, T.L. year 2001 ref In the UK, the idea of induced traffic was used as a grounds ... econappr documents divisionhomepage 031568.hcsp . However, despite the concept of induced traffic now being accepted, it is not always considered. A classic example of induced demand was the construction ... underestimated the level of demand, because some was induced, and thus the road did not have ... Induced traffic can be avoided if the generalised cost of travel does not decrease when new road capacity ... in an induced rise in overall traffic, because the shift of HOVs to the new lane releases capacity in the existing ... reply that the new induced traffic will generate more pollution and exacerbate the greenhouse ... guidance on modelling induced demand http www.cts.cv.imperial.ac.uk documents publications iccts00003.pdf A statistical analysis of induced travel effects in the US mid Atlantic region Fulton ... of Transportation Engineers www.ite.org , April, 2001, pp. 38 47. DEFAULTSORT Induced Demand ... more details
Induced gravity or emergent gravity is an idea in quantum gravity that space time background emerges as a mean field approximation of underlying microscopic degrees of freedom, similar to the fluid mechanics approximation of Bose Einstein condensate s. The concept was originally proposed by Andrei Sakharov in 1967. Sakharov observed that many condensed matter systems give rise to emergent phenomena which are identical to general relativity . For example, Crystallographic defect crystal defects can look like curvature and torsion in an Einstein Cartan theory Einstein Cartan spacetime . This allows one to create a theory of gravity with torsion from a World Crystal model of spacetime ref cite journal title Gravity as Theory of Defects in a Crystal with Only Second Gradient Elasticity author Hagen Kleinert H. Kleinert journal Annalen der Physik volume 44 page 117 year 1987 doi 10.1002 andp.19874990206 bibcode 1987AnP...499..117K ref in which the lattice spacing is of the order of a Planck length. Sakharov s idea was to start with an arbitrary background pseudo Riemannian manifold in modern treatments, possibly with torsion and introduce quantum fields matter on it but not introduce any gravitational dynamics explicitly. This gives rise to an effective action which to one loop order contains the Einstein Hilbert action with a cosmological constant . In other words, general relativity arises as an emergent property of matter fields and is not put in by hand. On the other hand, such models typically predict huge cosmological constant s. Some argue that the particular models proposed by Sakharov and others have been proven impossible by the Weinberg Witten theorem . But, models with emergent gravity are always possible as long as other things, such as spacetime dimensions, emerge ... degrees of freedom in induced gravity might be radically different. The bulk space time arises ... s induced gravity a modern perspective , 2002. http www.physik.fu berlin.de kleinert b11 psfiles ... more details
In mathematics and theoretical physics , the induced metric is the metric tensor defined on a submanifold which is calculated from the metric tensor on a larger manifold into which the submanifold is embedded. It may be calculated using the following formula written using Einstein summation convention math g ab partial a X mu partial b X nu g mu nu X alpha math Here math a,b math describe the indices of coordinates math xi a math of the submanifold while the functions math X mu xi a math encode the embedding into the higher dimensional manifold whose tangent indices are denoted math mu, nu math . Example Curve on a torus Let math begin align Pi colon mathcal C & to mathbb R 3 tau & mapsto left quad begin matrix x 1 a b cos n cdot tau cos m cdot tau x 2 a b cos n cdot tau sin m cdot tau x 3 b sin n cdot tau end matrix right. end align math be a map from the domain of the curve math mathcal C math with parameter math tau math into the euclidean manifold math mathbb R 3 math . Here math a,b,m,n in mathbb R math are constants. Then there is a metric given on math mathbb R 3 math as math g sum limits mu, nu g mu nu mathrm d x mu otimes mathrm d x nu quad text with quad g mu nu begin pmatrix 1 & 0 & 0 0 & 1 & 0 0 & 0 & 1 end pmatrix math . and we compute math g tau tau sum limits mu, nu frac partial x mu partial tau frac partial x nu partial tau underbrace g mu nu delta mu nu sum limits mu left frac partial x mu partial tau right 2 m 2 a 2 2m 2ab cos n cdot tau m 2b 2 cos 2 n cdot tau b 2n 2 math Therefore math g mathcal C m 2 a 2 2m 2ab cos n cdot tau m 2b 2 cos 2 n cdot tau b 2n 2 mathrm d tau otimes mathrm d tau math See also First fundamental form Category Differential geometry physics stub it Metrica indotta ru ... more details
This article compares the radioactivity release and decay from the Chernobyl disaster with various other events which involved a release of uncontrolled radioactivity. Chernobyl compared to background radiation Natural sources of radiation are very prevalent in the environment, and come from cosmic rays, food sources bananas have a particular high source , radon gas, granite and other dense rocks, and others. The collective radiation background dose for natural sources in Europe is about 500,000 man Sieverts per year. The total dose from Chernobyl is estimated at 80,000 man sieverts, or roughly 1 6 as much. ref http www.springerlink.com content p5070vl7v843r063 ref However, some individuals, particular in areas adjacent the reactor, received significantly higher doses. Chernobyl s radiation was detectable across Western Europe. Average doses received ranged from 0.02 mrem Portugal to 38 mrem portions of Germany . ref http www.springerlink.com content p5070vl7v843r063 ref Chernobyl compared with an atomic bomb Far fewer people died as an immediate result of the Chernobyl event than Atomic ... of environmental radioactivity ref suggests that the two events can not be simply compared with a number suggesting that one was XX times larger than the other . The radioactivity released at Chernobyl ... of radioactivity . The following gamma emitting isotopes are modeled sup 131 sup I, sup ... by an analogous method. Chernobyl compared with Tomsk 7 The release of radioactivity which occurred ... elements are extracted by the tributyl phosphate. Due to the radiation induced degradation of tributyl ... of these accidents. A release of radioactivity occurred as a result of the Tokaimura event. The building ... to retard the spread of radioactivity. Because the temperature rise in the nuclear reaction vessel ... the radioactivity remained confined to within the actinide metal objects which were part of the experimental system. Even the SL 1 accident failed to release much radioactivity outside the building ... more details
In nuclear physics , Ronen s golden rule for cluster radioactivity is that the most favorable parents for heavy ion emission cluster radioactivity are those that emit clusters which have atomic mass math A z math which is given by math A z A z 2 4 B z 2 math . The atomic number math Z math is even, math A 0 0 math , math B z 2 0 math for math Z 2 math odd and math B z 2 2 math for math Z 2 math even .The daughter nuclei is preferably magic, close to the double magic sup 208 sup Pb. References 1. Tavares, O.A.P., Roberto, L.A.M. and Medeiros, E.L., Radioactive decay by the emission of heavy nuclear fragments . Phys. Scr. u 76 u , 376, 2007 . Category Nuclear physics ... more details
The Commission for Independent Research and Information on Radioactivity actual name, Commission de Recherche et d Information Ind pendantes sur la Radioactivit , or CRIIRAD is a France French NGO which specializes in the analysis of radioactivity in the environment. It was created in the aftermath of the Chernobyl accident Chernobyl catastrophe on April 26, 1986. It revendicates being independent from nuclear exploitants, the state and all political parties . The CRIIRAD has an analysis laboratory, equipped for identification of radioactive contamination food, water, etc. , which has been delivered the technical qualification certificate by the Health minister. It operates both in France and abroad, and is funded by its investigations more than a thousand studies since its creation and its memberships adhesions. As all other French NGOs, it is regulated by the 1901 law on non profit organizations . Among other studies by the CRIIRAD, its investigations on the contamination of the French territory following the 1986 Chernobyl catastrophe are the most known, although it also studied the consequences of the Marcoule Marcoule nuclear power plant , the Fukushima I nuclear accidents , and published an atlas of radioactive contamination in Europe and France. See also Chernobyl accident Chernobyl catastrophe Yury Bandazhevsky A Belarusian scientist, repressed by the Belarusian state, who has been supported by the CRIIRAD List of Chernobyl related articles External links fr http www.criirad.org official website http www.criirad.org actualites dossier2011 japon bis risks in France v4.pdf Fukushima contamination in France What are the risks? Category Chernobyl disaster Category Radiation health effects researchers Category Nuclear research centers Category Nuclear energy in France Category Non governmental organizations based in France de Commission de recherche et d information ind pendantes sur la radioactivit fr Commission de recherche et d information ind pendantes sur la ... more details
orphan date January 2010 For other uses, see LII . Laser induced incandescence LII is a non intrusive method of measuring time resolved soot particle volume fraction and primary particle sizes in flame s. See also Laser induced fluorescence Planar laser induced fluorescence Category Spectroscopy physics stub chemistry stub ... more details
Orphan date February 2009 Mechanically induced modulation is an optical Signalling telecommunication signal modulation induced by mechanical means. An example of deleterious mechanically induced modulation is speckle noise created in a multimode fiber by an imperfect Fusion splicing splice or imperfectly mated connectors. Mechanical disturbance of the fiber ahead of the joint will introduce changes in the modal structure, resulting in variations of joint loss. This is a subset of many mechanisms that can lead to modal noise in an optical system. References FS1037C Category Fiber optic communications telecomm stub ... more details
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