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62bd4e2f6a0290ccca6586e3089262afd1a2b058
a potential difference (voltage) between two points of
a potential difference (voltage) between two points of a conductor creates an electric field that accelerates charge carriers in the direction of the electric field, giving them kinetic energy. when the charged particles collide with the quasi-particles in the conductor (i.e. the canonically quantized, ionic lattice os...
wikipedia
514e63d7a8261d1a49c3c566cd47512da4859e2d
in 1841 and 1842, subsequent experiments showed that
in 1841 and 1842, subsequent experiments showed that the amount of heat generated was proportional to the chemical energy used in the voltaic pile that generated the template. this led joule to reject the caloric theory (at that time the dominant theory) in favor of the mechanical theory of heat (according to which hea...
wikipedia
8f7761026ec91ca46af2de9a7fe18689e8397216
james prescott joule first published in december 1840,
james prescott joule first published in december 1840, an abstract in the proceedings of the royal society, suggesting that heat could be generated by an electrical current. joule immersed a length of wire in a fixed mass of water and measured the temperature rise due to a known current flowing through the wire for a 3...
wikipedia
30c96d5510d5af7bc0d7a9e355a9f032531da5eb
joule's first law (also just joule's law), also
joule's first law (also just joule's law), also known in countries of the former ussr as the joule–lenz law, states that the power of heating generated by an electrical conductor equals the product of its resistance and the square of the current. joule heating affects the whole electric conductor, unlike the peltier ef...
wikipedia
d4cf0fa4a3aa94124eb755ec2dd1aa0015de7504
adamo giuliano fantilli is a canadian professional ice
adamo giuliano fantilli is a canadian professional ice hockey centre for the columbus blue jackets of the national hockey league (nhl). he was drafted third overall by the blue jackets in the 2023 nhl entry draft. during his freshman season at the university of michigan he was the leading goal and point-scorer and won ...
wikipedia
a2a4a6eef26a447889bf501afb6421f2dd2e6379
after missing the final months of the 2023–24
after missing the final months of the 2023–24 season with injury, fantilli rejoined the senior national team for the 2024 iihf world championship. citing his shortened professional season as a motive for competing, he said: "i have to get my game going. that's my concern." however, fantilli was subsequently dropped fro...
wikipedia
99ddb9ffe57a25e7ee313366208c0fb92e734034
on may 5, 2023, fantilli was named to
on may 5, 2023, fantilli was named to canada's national senior team at the 2023 iihf world championship. he scored the game-winning goal in the semi-final against latvia, his first of the tournament. he finished the tournament with one goal and two assists and won a gold medal. he became the second canadian to win gold...
wikipedia
1c5e1e1c32f53b7580b010aa1ad03cd50cd871f0
in 2022, fantilli was named to canada's national
in 2022, fantilli was named to canada's national under-18 team at the 2022 iihf world u18 championships, where he again served as alternate captain. he recorded one goal and five assists in four games before the team was knocked out in the quarterfinal stage. on december 12, 2022, he was named to canada's national juni...
wikipedia
64d33769c88d220599c14097e11520030109d41e
fantilli made his nhl debut on october 12,
fantilli made his nhl debut on october 12, 2023, his 19th birthday, against the philadelphia flyers. he scored his first career nhl goal on october 21, 2023, as part of a 5–4 overtime win against the minnesota wild. fantilli played 49 games before his debut season was cut short by a calf laceration in a january 28 game...
wikipedia
c6d665fa32bd61badb35d7dd89a442429102f566
fantilli was drafted third overall by the columbus
fantilli was drafted third overall by the columbus blue jackets in the 2023 nhl entry draft. on july 1, 2023, fantilli signed a three-year entry-level contract with the blue jackets. he will forego the rest of his college career to go play in the nhl.
wikipedia
e46a5979567a1ae4dd48b7a109c17d1b2975dd92
during the 2023 big ten men's ice hockey
during the 2023 big ten men's ice hockey tournament he set the big ten tournament record for goals in a single tournament with seven and in points with 11. he was subsequently named the big ten tournament mvp. he finished his freshman year with 30 goals and 35 assists in 36 games. he led the nation in points, and goals...
wikipedia
310328248efc4bec1e1f09c934b9d66ebb51d6b3
in august 2021, fantilli verbally committed to the
in august 2021, fantilli verbally committed to the university of michigan. he began his collegiate career for the michigan wolverines during the 2022–23 season. he made his debut for michigan on october 7, 2022, in a game against lindenwood, where he won 15 of 19 faceoffs and recorded two assists. the next day, he scor...
wikipedia
7a1f12baead49c1f5207df32fe6b48cdb14c863f
in august 2021, fantilli verbally committed to the
regular season he recorded 11 goals and 19 assists in 19 conference games for a league-best 1.58 points per game. following an outstanding season, he was named to the all- big ten freshman team, the all-big ten first team and was named big ten freshman of the year.
wikipedia
d8f1521d9bd8c70f4754223884e2c899dac5ec3f
fantilli attended kimball union academy where he recorded
fantilli attended kimball union academy where he recorded 18 goals and 18 assists in 25 games. on march 25, 2020, fantilli signed a ushl tender agreement with the chicago steel for the 2020–21 season. during the regular season he recorded 18 goals and 18 assists in 49 games for the steel and was named to the ushl all-r...
wikipedia
f0a4ac45fe20941468b59a68706102b7ed918c4a
fantilli was drafted in the first round, 18th
fantilli was drafted in the first round, 18th overall, by the saginaw spirit in the 2020 ohl priority selection draft. he was considered the top canadian prospect in the draft, however, he had already committed to play for the chicago steel. on september 13, 2021, the spirit exercised their defected player rule and tra...
wikipedia
03bede3f3d9f5dd05461a5b2e5ae091653820a14
adamo giuliano fantilli (born october 12, 2004) is
adamo giuliano fantilli (born october 12, 2004) is a canadian professional ice hockey centre for the columbus blue jackets of the national hockey league (nhl). he was drafted third overall by the blue jackets in the 2023 nhl entry draft. during his freshman season at the university of michigan he was the leading goal a...
wikipedia
42fa5afb04d5790c5fd40555c570af55f21ad7b4
following three seasons in the khl with spartak
following three seasons in the khl with spartak moscow, nikishin was traded to powerhouse club ska saint petersburg in exchange for 5 contracted players and the rights to four further players and an additional 50 million rubles on 31 july 2022. with saint petersburg, nikishin's production skyrocketed, putting up 55 poi...
wikipedia
413ccd4fca1817104049f417024e6224efc649d2
nikishin made his khl debut for hc spartak
nikishin made his khl debut for hc spartak moskva during the 2019–20 season. he was drafted by the carolina hurricanes in the 3rd round of the 2020 nhl entry draft with the 69th overall pick.
wikipedia
6728890e238e2df15781637f72b90d836336bfc9
alexander alexandrovich nikishin (russian: Александр Александрович Никишин; born
alexander alexandrovich nikishin (russian: Александр Александрович Никишин; born 2 october 2001) is a russian professional ice hockey defenseman currently playing for ska saint petersburg in the kontinental hockey league (khl).
wikipedia
3a53a3bf64ed1c97d0c62cf36c5ab2183ac857c0
john francis "moe" murphy was an american professional
john francis "moe" murphy was an american professional basketball and baseball player. murphy was born in philadelphia, pennsylvania and attended simon gratz high school, where he led the philadelphia public league in points per game with 13.7 in 1942. he spent three seasons playing for the wilmington bombers of the am...
wikipedia
ae22f06e0d5bfa3b88195970415ff33141ba41cd
john francis " moe " murphy (september 13,
john francis " moe " murphy (september 13, 1924 – january 29, 2003) was an american professional basketball and baseball player. murphy was born in philadelphia, pennsylvania and attended simon gratz high school, where he led the philadelphia public league in points per game with 13.7 in 1942. he spent three seasons pl...
wikipedia
2e5c17f405d205bd8f24d3b4bc371a423522169f
the peugeot 8aa, or l112, is a water-cooled
the peugeot 8aa, or l112, is a water-cooled v8 aircraft engine that equipped the 1,123 voisin viii bombers and fighters built during ww1. the 8aa was the first engine designed by peugeot for airplane use and the only one that saw service in ww1. in publications the engine is often referred to as the peugeot 200 hp, or ...
wikipedia
0769c1413cb36dc7ed0734009281e22a10f76cef
the peugeot 8aa was a remarkably fuel efficient
the peugeot 8aa was a remarkably fuel efficient engine for its time. at its most efficient point, the engine's specific fuel consumption was 0.252 kg/kwh (0.414 lb/(hp⋅h)) corresponding to a thermal efficiency of more than 30%.
wikipedia
edb42f12bd1437d4ade23a64002a4ff2b12f895c
the peugeot 8aa shared many common parts with
the peugeot 8aa shared many common parts with the hispano-suiza 8 and its british derivative the wolseley viper. camshafts, piston rings and some bearings were interchangeable. peugeot was one of the main licensed producers of hispano-suiza 8 engines.
wikipedia
159bae159334f8d584cfceeda45c145b0c25872d
2 carburetors (one for each cylinder bank) are
2 carburetors (one for each cylinder bank) are attached to the out-side inlet manifolds. carburetors were heated by the exhaust however this arrangement was ineffective at the cold temperatures found at high altitudes which contributed to the type's poor reliability.
wikipedia
fbf0817470ead36342c7bb2e6ccbfc31cb002803
the cylinders are cast from iron in blocks
the cylinders are cast from iron in blocks of four with integral water jackets. in each cylinder head there are four inclined valves guided in bronze bushings. the engine's four camshafts (two per cylinder bank) are enclosed in aluminum housings and operate the valves through tappets.
wikipedia
225d388eed5d15dd4feac9dc23eeab7971273902
a shaft, extending directly back through the vee,
a shaft, extending directly back through the vee, drives the camshaft spur gear train and the accessory units. the crankcase is of the barrel type with the four-throw crankshaft supported on three large double-row ball bearings. the crankshaft is made from two sections and is joined at the center bearing by a taper, ke...
wikipedia
a388ab8907b93c56954a7f8ac5e29eb305a9a0b6
the engine's eight cylinders are in a 90
the engine's eight cylinders are in a 90 degree vee arrangement. reduction gears rotated the propeller at half the speed of the crankshaft. the propeller shaft extends far out in front of the crankcase and is mounted on ball bearings.
wikipedia
9430b3fc23b9d51ba85b386ed31aba2fa7654700
peugeot's design followed that of their successful racing
peugeot's design followed that of their successful racing car engines which had been in production since 1910. for its time period, the engine had advanced features including double overhead camshafts (dohc) and a dry sump design patented by peugeot.
wikipedia
8b3a42f77e208aa8713aa35dd223c52fa22bdf67
the peugeot 8aa was developed to meet a
the peugeot 8aa was developed to meet a french military requirement for 200 hp aero-engines to equip a new class of bomber aircraft designed to hit targets inside germany. to achieve this the engines needed to run for six hours with most of the journey taking place at altitudes around 4,400 m (14,400 ft). the requireme...
wikipedia
417224344f967823dc937c91d6aa82f68166d71d
the peugeot 8aa, or l112, is a water-cooled
the peugeot 8aa, or l112, is a water-cooled v8 aircraft engine that equipped the 1,123 voisin viii bombers and fighters built during ww1. the 8aa was the first engine designed by peugeot for airplane use and the only one that saw service in ww1. in publications the engine is often referred to as the peugeot 200 hp, or ...
wikipedia
26ac7c080c27bb906099ff4c00c432c3dd6dc9b1
his work has been cited, together with that
his work has been cited, together with that of marcel riesz, for its importance to clifford algebras and mathematical physics in the proceedings of a workshop held in france in 1989 which had been dedicated to these two mathematicians.
wikipedia
90223887269721e2dffe0daa053add446915c7c6
he wrote a series of publications of 1957/1958
he wrote a series of publications of 1957/1958 on geometric algebras that stand in relation to quantum physics and quantum field theory. he pointed out that those algebras can be described in terms of extensions of the commutative and the anti-commutative grassmann algebras which have the same structure as the boson al...
wikipedia
92d59536310a0299e06ffc317e59d1d999a65064
in the university of são paulo had schönberg
in the university of são paulo had schönberg interacted closely with david bohm during the final years of bohm's exile in brazil, and, in 1954, schönberg demonstrated a link among the quantized motion of the madelung fluid and the trajectories of the de broglie–bohm theory.
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1adf253285801d99ac9193ca3e8dfc7298acad24
together with indian physicist subrahmanyan chandrasekhar (1910–1995), he
together with indian physicist subrahmanyan chandrasekhar (1910–1995), he discovered and published in 1942 the so-called schönberg–chandrasekhar limit, which is the maximum mass of the core of a star that can support the overlying layers against gravitational collapse, once the core hydrogen is exhausted.
wikipedia
1a7d223ca701a0f67c1a324e4b35fbf85d496d9b
widely regarded as one of brazil's most important
widely regarded as one of brazil's most important theoretical physicists, schenberg is best remembered for his contributions to astrophysics, particularly the theory of nuclear processes in the formation of supernova stars. he provided the inspiration for the name of the so-called urca process, a cycle of nuclear react...
wikipedia
a88e89be774c452180a643d8c314b01a2eb17290
schenberg was born in recife, brazil as mayer
schenberg was born in recife, brazil as mayer schönberg. his parents were russian jews of german origin. from early on he showed remarkable ability for mathematics, enchanting himself with geometry, which had a strong influence on his works. he took the primary and secondary courses in recife. because of his family's f...
wikipedia
8e6dc412abc8a93e22296281ad4146aee05ed030
tan cheng hoe is a malaysian football manager
tan cheng hoe is a malaysian football manager and former football player who was recently the manager of thai league 1 club police tero. he was the assistant coach for the malaysia national team during k. rajagopal and nelo vingada era before he was chosen as the head coach of the national team.
wikipedia
c75275ceef32fbb8e515f0fa359afc4b8f013f96
on 29 february 2024, thai league 1 club
on 29 february 2024, thai league 1 club police tero announced the appointment of tan as the head coach and designated worrawoot srimaka as the technical director. he secured nine points from his games in charge, which were ultimately not enough to keep the team in the league, with the club's relegation confirmed on 13 ...
wikipedia
5476394b1131798a7409caf1b619173d59720dff
on 24 september 2022, tan cheng hoe appointed
on 24 september 2022, tan cheng hoe appointed as selangor first team head coach. tan, who took the helm of selangor in september 2022, has been instrumental in the club's recent successes, notably leading them to runner-up positions in both the 2022 malaysia cup and the 2023 malaysia super league. such feats not only e...
wikipedia
da98c1d75c0e07fd2740886c486d5f3992846e59
tan continued to lead the malaysian team in
tan continued to lead the malaysian team in the 2022 fifa world cup qualification after he been reward by the football association of malaysia (fam) to manage the team for another two years until his contract ended in 2020. although the team under his management able to easily routed timor-leste in the first round by 1...
wikipedia
abffbc5350625c1f67b0d810dabcd053a0f5b896
this was continued in the finals first leg
this was continued in the finals first leg when the malaysian team under his led also managed to hold the tournament favourites of vietnam 2–2 at home in their second meet in the tournament despite the latter had already scoring two goals in the first half. however, in the second leg in hanoi, his team failed to repeat...
wikipedia
63e519a2293412a6697c2b72a4251889a0fc374a
in the preparation for the 2018 aff championship,
in the preparation for the 2018 aff championship, tan had mentioned through an article published by the fox sports asia that malaysia are underdogs team and hope their country fans will not put their hope too much despite being drawn into a favourable group a consisting of vietnam, myanmar, cambodia and laos, adding th...
wikipedia
51bd14e0eb94c183169af924184ee3a6a76a0a76
tan began his 2nd spell with malaysia in
tan began his 2nd spell with malaysia in april 2017 as he took up the position of assistant manager under nelo vingada. tan was then made the head coach of malaysia after vingada stepped down following a string of poor results.
wikipedia
8ed96b64a056401ec2709e6e1f429987a30deceb
a break from football lasting 5 years then
a break from football lasting 5 years then followed with tan's next role as manager at second-tier malaysia premier league club, kedah beginning in april 2014. in 2015, he guided kedah to win the 2015 malaysia premier league which also gain promotion to the 2016 malaysia super league. he was named the m-league's best c...
wikipedia
ecf8d6ea99de51bde5b1a6043963e22468baa5af
tan was the assistant coach to k. rajagopal
tan was the assistant coach to k. rajagopal from 2004 to 2013. tan worked as an under 19s coach for malaysia from december 2004 until october 2009. tan continued his development as coach for harimau muda from october 2007 until october 2009. under rajagopal and tan, malaysia achieved many good results such as reaching ...
wikipedia
a4b8f9596990eb9771276514056f4f5413e773e4
tan made an appearance for malaysia selection in
tan made an appearance for malaysia selection in a match against aston villa on 20 may 1991. in september 1991, he was part of malaysia b team managed by m. karathu for taan cup, an invitational tournament in kathmandu nepal. malaysia b team won the tournament beating tiong bahru of singapore 2–0.
wikipedia
525ef777ad84dd1c153844020b5ee18a4fa49cc3
tan cheng hoe (chinese: 陈清和) is a malaysian
tan cheng hoe (chinese: 陈清和) is a malaysian football manager and former football player who was recently the manager of thai league 1 club police tero. he was the assistant coach for the malaysia national team during k. rajagopal and nelo vingada era before he was chosen as the head coach of the national team.
wikipedia
8fe8d7fa5bdfe7cc0e41e476069615818df449ff
testosterone enanthate is an androgen and anabolic steroid
testosterone enanthate is an androgen and anabolic steroid (aas) medication which is used mainly in the treatment of low testosterone levels in men. it is also used in hormone therapy for transgender men. it is given by injection into muscle or subcutaneously usually once every one to four weeks. side effects of testos...
wikipedia
301cfae91d5370a17f45e77f883253c3ee31feb7
on october 1, 2018, the u.s. food and
on october 1, 2018, the u.s. food and drug administration (fda) announced the approval of xyosted. xyosted, a product of antares pharma, inc., is a single-use disposable auto-injector that dispenses testosterone enanthate. xyosted is the first fda-approved subcutaneous testosterone enanthate product for testosterone re...
wikipedia
bdb86060c94a2749b26b4a2de9e531ae3c0b82bc
testosterone enanthate, or testosterone 17β-heptanoate, is a synthetic
testosterone enanthate, or testosterone 17β-heptanoate, is a synthetic androstane steroid and a derivative of testosterone. it is an androgen ester; specifically, it is the c17β enanthate (heptanoate) ester of testosterone.
wikipedia
91b6a50fdfd95189baf2a85878166282a779537f
testosterone enanthate has an elimination half-life of 4.5
testosterone enanthate has an elimination half-life of 4.5 days and a mean residence time of 8.5 days when used as a depot intramuscular injection. it requires frequent administration of approximately once per week, and large fluctuations in testosterone levels result with it, with levels initially being elevated and s...
wikipedia
57f40eecde9f3aa232fa5d8718c4787e18fd776f
testosterone cypionate is converted by the body to
testosterone cypionate is converted by the body to testosterone that has both androgenic effects and anabolic effects; still, the relative potency of these effects can depend on various factors and is a topic of ongoing research. testosterone can either directly exert effects on target tissues or be metabolized by 5α-r...
wikipedia
e37e203ef0f22791537862e83b9d30d881fa5899
side effects of testosterone enanthate include virilization among
side effects of testosterone enanthate include virilization among others. approximately 10 percent of testosterone enanthate will be converted to dihydrotestosterone in normal men. dihydrotestosterone (dht) can promote masculine characteristics in both males and females. these masculine characteristics include: clitora...
wikipedia
7eafe4bae78d2af3afc7c9c0010f2cf880052dfc
testosterone enanthate is used primarily in androgen replacement
testosterone enanthate is used primarily in androgen replacement therapy. it is the most widely used form of testosterone in androgen replacement therapy. the medication is specifically approved, in the united states, for the treatment of hypogonadism in men, delayed puberty in boys, and breast cancer in women. it is a...
wikipedia
3d2d037328206fd5e4353f68324adacf87011cb1
testosterone enanthate was introduced for medical use in
testosterone enanthate was introduced for medical use in 1954. along with testosterone cypionate, testosterone undecanoate, and testosterone propionate, it is one of the most widely used testosterone esters. in addition to its medical use, testosterone enanthate is used to improve physique and performance. the drug is ...
wikipedia
b235d84a542f693cc56a2d331b10c24766212a98
side effects of testosterone enanthate include symptoms of
side effects of testosterone enanthate include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. the drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (ar), the biological target of androgens like testosterone and d...
wikipedia
d5e812bbd7553a78659a5b1799c8414e74e630be
testosterone enanthate is an androgen and anabolic steroid
testosterone enanthate is an androgen and anabolic steroid (aas) medication which is used mainly in the treatment of low testosterone levels in men. it is also used in hormone therapy for transgender men. it is given by injection into muscle or subcutaneously usually once every one to four weeks.
wikipedia
3105bc11a5421346f0fb1acb71845ff9e72f4805
tatyana olegovna shaposhnikova is a russian-born swedish mathematician.
tatyana olegovna shaposhnikova is a russian-born swedish mathematician. she is best known for her work in the theory of multipliers in function spaces, partial differential operators and history of mathematics, some of which was partly done jointly with vladimir maz'ya. she is also a translator of both scientific and l...
wikipedia
569256452b14db048d74e34fb3bd5273a9fe2ef9
in 2005 she began translating swedish children's books
in 2005 she began translating swedish children's books into russian. among them are " kerstin and i " by astrid lindgren, " mechanical santa claus " by sven nordqvist and two books of the " loranga " series by barbro lindgren.
wikipedia
c93dacce95334360e8b6a5e13fb047b9dbed35ba
shaposhnikova began translating fiction while still living in
shaposhnikova began translating fiction while still living in russia. in the 1970s she translated into russian " the voyage of the dawn treader ", " the silver chair " and the " screwtape letters " by c. s. lewis. these translations were impossible to publish due to ideological reasons and were distributed as samizdat:...
wikipedia
1f45b056cec257e1e82904566f02c213dbc4a4c8
shaposhnikova has translated and edited several mathematical monographs:
shaposhnikova has translated and edited several mathematical monographs: it is worth to note the works by koshelev et al. (1975) and by mikhlin (1979), the book on sobolev spaces by maz'ya (1985), and the books by kresin & maz'ya (2007) and by maz'ya & soloviev (2010). however, her work is not restricted only to the tr...
wikipedia
4f130e696c0f93bac017e03c3e685e9b588043b4
her prize winning book on jacques hadamard, coauthored
her prize winning book on jacques hadamard, coauthored with v. maz'ya, was published in 1998 jointly by the american mathematical society and the london mathematical society. an earlier work on the same subject was written by her jointly with e. polishchuk (1990). her recent activity in this field includes the paper (s...
wikipedia
bdd8fa3e89011a72a478e35f7c2ec21db9e2498e
based on her researches on the theory of
based on her researches on the theory of multipliers, t. shaposhnikova gave various applications of this theory to the study of solutions to second order linear and quasilinear elliptic partial differential equations and systems of such equations: this was a consequence of the fact that, in several cases, such solution...
wikipedia
871d3b4a608429a51c0c352e9f8247a0d9faecb6
from 1979 on, the theory of multipliers in
from 1979 on, the theory of multipliers in various spaces of differentiable functions has been the main research theme of her work. she found conditions for the boundedness of singular integrals and pseudodifferential operators acting between pairs of sobolev spaces in 1995. in 1989 she showed that multipliers in besse...
wikipedia
5bc367e9b81b9cb87258229afef28a781af8949b
in march 2003 shaposhnikova and vladimir maz'ya were
in march 2003 shaposhnikova and vladimir maz'ya were awarded the verdaguer prize by the french academy of sciences for their work resulting in the first scientific biography of jacques hadamard. in may 2010 she was awarded the thureus prize by the royal society of sciences in uppsala " for her outstanding contribution ...
wikipedia
d3b80c79156f960bcb0dcf290667756e19047f11
t.o. shaposhnikova graduated from leningrad university in 1969.
t.o. shaposhnikova graduated from leningrad university in 1969. from 1969 to 1972 she was a graduate student at the same university. in 1973 she was awarded the kandidat nauk degree. from 1973 to 1990 she worked in the mathematics departments of a number of technical institutes in leningrad, first as an assistant and t...
wikipedia
e6b48794b325b8c05501fc187e2e284e7b4baf32
tatyana olegovna shaposhnikova (russian: Татьяна Олеговна Шапошникова, born
tatyana olegovna shaposhnikova (russian: Татьяна Олеговна Шапошникова, born 1946) is a russian -born swedish mathematician. she is best known for her work in the theory of multipliers in function spaces, partial differential operators and history of mathematics, some of which was partly done jointly with vladimir maz'y...
wikipedia
7e7bd2190c4bb2b956211bb772949f41b8d01a0f
in mathematics, the integral of a non-negative function
in mathematics, the integral of a non-negative function of a single variable can be regarded, in the simplest case, as the area between the graph of that function and the x axis. the lebesgue integral, named after french mathematician henri lebesgue, is one way to make this concept rigorous and to extend it to more gen...
wikipedia
2c0fad84207fbd9cb8fa05612d7309be1f6831f8
the main purpose of the lebesgue integral is
the main purpose of the lebesgue integral is to provide an integral notion where limits of integrals hold under mild assumptions. there is no guarantee that every function is lebesgue integrable. but it may happen that improper integrals exist for functions that are not lebesgue integrable. one example would be the sin...
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b814965510c971faf9fcbf93030c3fd2222330f1
more generally, when the measure space on which
more generally, when the measure space on which the functions are defined is also a locally compact topological space (as is the case with the real numbers r), measures compatible with the topology in a suitable sense (radon measures, of which the lebesgue measure is an example) an integral with respect to them can be ...
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24cb252d270717b388123639a02e63891350d39b
then c is a normed vector space (and
then c is a normed vector space (and in particular, it is a metric space.) all metric spaces have hausdorff completions, so let l be its completion. this space is isomorphic to the space of lebesgue integrable functions modulo the subspace of functions with integral zero. furthermore, the riemann integral ∫ is a unifor...
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3e356fb0e7ec55b6b357c3a407dadc7074954029
let c be the space of all real-valued
let c be the space of all real-valued compactly supported continuous functions of r. define a norm on c by ‖ f ‖ = ∫ | f (x) | d x. {\displaystyle \left\|f\right\|=\int |f(x)|\,dx.}
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fd4b8bbb0a97c6c96ed10cab18a7634ed6bbed4c
there is also an alternative approach to developing
there is also an alternative approach to developing the theory of integration via methods of functional analysis. the riemann integral exists for any continuous function f of compact support defined on r (or a fixed open subset). integrals of more general functions can be built starting from these integrals.
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0aa12605ea82ceebc2a2a37f011945c529012a6c
two functions are said to be equal almost
two functions are said to be equal almost everywhere (f = a.e. g {\displaystyle f\ {\stackrel {\text{a.e.}}{=}}\ g} for short) if { x ∣ f (x) ≠ g (x) } {\displaystyle \{x\mid f(x)\neq g(x)\}} is a subset of a null set. measurability of the set { x ∣ f (x) ≠ g (x) } {\displaystyle \{x\mid f(x)\neq g(x)\}} is not require...
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83ace34316b50e052dd1d535db2666893279f424
the function g is zero everywhere, except on
the function g is zero everywhere, except on a finite set of points. hence its riemann integral is zero. each g is non-negative, and this sequence of functions is monotonically increasing, but its limit as k → ∞ is 1, which is not riemann integrable.
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d1ebc0464e173ec38cd0158086c385a6ec3731ff
as shown above, the indicator function 1 on
as shown above, the indicator function 1 on the rationals is not riemann integrable. in particular, the monotone convergence theorem fails. to see why, let { a } be an enumeration of all the rational numbers in (they are countable so this can be done). then let g k (x) = { 1 if x = a j, j ≤ k 0 otherwise {\displaystyle...
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0b8b4cc1fec1571ee03795b208f72374fa03ccdf
a technical issue in lebesgue integration is that
a technical issue in lebesgue integration is that the domain of integration is defined as a set (a subset of a measure space), with no notion of orientation. in elementary calculus, one defines integration with respect to an orientation: ∫ b a f = − ∫ a b f. {\displaystyle \int _{b}^{a}f=-\int _{a}^{b}f.} generalizing ...
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67f4f0f16e6be21765dae71e45025113e75dcfe4
if h = f + ig for real-valued
if h = f + ig for real-valued integrable functions f, g, then the integral of h is defined by ∫ h d μ = ∫ f d μ + i ∫ g d μ. {\displaystyle \int h\,d\mu =\int f\,d\mu +i\int g\,d\mu.}
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944294b24cafaa597fbde448e0cabfe4110a89dd
assuming that f is measurable and non-negative, the
assuming that f is measurable and non-negative, the function f ∗ (t) = def μ ({ x ∈ e ∣ f (x) > t }). {\displaystyle f^{*}(t)\ {\stackrel {\text{def}}{=}}\ \mu \left(\{x\in e\mid f(x)>t\}\right).} is monotonically non-increasing. the lebesgue integral may then be defined as the improper riemann integral of f: ∫ e f d μ...
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12679995c76d72703d7a81103d83b0656cceb789
∫ f d μ = ∫ f +
∫ f d μ = ∫ f + d μ − ∫ f − d μ. {\displaystyle \int f\,d\mu =\int f^{+}\,d\mu -\int f^{-}\,d\mu.}
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a3244fcfce0cca99e80d7946e2c5515908bb48b4
min (∫ f + d μ, ∫ f
min (∫ f + d μ, ∫ f − d μ) < ∞. {\displaystyle \min \left(\int f^{+}\,d\mu,\int f^{-}\,d\mu \right)<\infty.}
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1f01c5cff380f37b2a4bf1bc2d3d01d64f118536
we say that the lebesgue integral of the
we say that the lebesgue integral of the measurable function f exists, or is defined if at least one of ∫ f + d μ {\textstyle \int f^{+}\,d\mu } and ∫ f − d μ {\textstyle \int f^{-}\,d\mu } is finite:
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9b74570b71b19aada993f2322a5c57a38b367b29
where f + (x) = { f (x)
where f + (x) = { f (x) − if f (x) > 0, 0 otherwise, f − (x) = { − f (x) if f (x) < 0, 0 otherwise. {\displaystyle {\begin{aligned}f^{+}(x)&={\begin{cases}f(x){\hphantom {-}}&{\text{if }}f(x)>0,\\0&{\text{otherwise}},\end{cases}}\\f^{-}(x)&={\begin{cases}-f(x)&{\text{if }}f(x)<0,\\0&{\text{otherwise}}.\end{cases}}\end{...
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38c5d9dbfe97f688b808a6465a79b270812efb58
to handle signed functions, we need a few
to handle signed functions, we need a few more definitions. if f is a measurable function of the set e to the reals (including ±∞), then we can write f = f + − f −, {\displaystyle f=f^{+}-f^{-},}
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3b75c6a6b7966af87a4b17ae8ef504eee1c503e2
it is often useful to have a particular
it is often useful to have a particular sequence of simple functions that approximates the lebesgue integral well (analogously to a riemann sum). for a non-negative measurable function f, let s n (x) {\textstyle s_{n}(x)} be the simple function whose value is k / 2 n {\textstyle k/2^{n}} whenever k / 2 n ≤ f (x) < (k +...
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8e76b318fe53f94119f3ea0a6a0e57d776fe732c
we have defined the integral of f for
we have defined the integral of f for any non-negative extended real-valued measurable function on e. for some functions, this integral ∫ e f d μ {\textstyle \int _{e}f\,d\mu } is infinite.
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42a35612c8c52e8d40b2932e5e7f35884cdcec6c
we need to show this integral coincides with
we need to show this integral coincides with the preceding one, defined on the set of simple functions, when e is a segment. there is also the question of whether this corresponds in any way to a riemann notion of integration. it is possible to prove that the answer to both questions is yes.
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f1da2bc863a0e394e31797df6f0f7c80ddd17a83
∫ e f d μ = sup {
∫ e f d μ = sup { ∫ e s d μ: 0 ≤ s ≤ f, s simple }. {\displaystyle \int _{e}f\,d\mu =\sup \left\{\,\int _{e}s\,d\mu:0\leq s\leq f,\ s\ {\text{simple}}\,\right\}.}
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c1b2c9dd5f27a0fc3243454ca5dc242e49468d62
∫ b s d μ = ∫ 1
∫ b s d μ = ∫ 1 b s d μ = ∑ k a k μ (s k ∩ b). {\displaystyle \int _{b}s\,\mathrm {d} \mu =\int 1_{b}\,s\,\mathrm {d} \mu =\sum _{k}a_{k}\,\mu (s_{k}\cap b).}
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982a7e582e1a7d29d45212fd27d8f2eeb93f3e60
∫ (∑ k a k 1 s k)
∫ (∑ k a k 1 s k) d μ = ∑ k a k ∫ 1 s k d μ = ∑ k a k μ (s k) {\displaystyle \int \left(\sum _{k}a_{k}1_{s_{k}}\right)\,d\mu =\sum _{k}a_{k}\int 1_{s_{k}}\,d\mu =\sum _{k}a_{k}\,\mu (s_{k})}
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5063abfa1d8466b7e1644a49db37acfcfbb2b6d1
one approach to constructing the lebesgue integral is
one approach to constructing the lebesgue integral is to make use of so-called simple functions: finite, real linear combinations of indicator functions. simple functions that lie directly underneath a given function f can be constructed by partitioning the range of f into a finite number of layers. the intersection of...
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885c6203fe9e76e9b1b6955705f2b6f8d435e91f
∫ e f d μ = ∫ e
∫ e f d μ = ∫ e f (x) d μ (x) = ∫ e f (x) μ (d x). {\displaystyle \int _{e}f\,d\mu =\int _{e}f(x)\,d\mu (x)=\int _{e}f(x)\,\mu (dx).}
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641b7349157437f8e2f3ba4b4aaa7d99f18a1b3d
sup k ∈ n f k, lim inf
sup k ∈ n f k, lim inf k ∈ n f k, lim sup k ∈ n f k {\displaystyle \sup _{k\in \mathbb {n} }f_{k},\quad \liminf _{k\in \mathbb {n} }f_{k},\quad \limsup _{k\in \mathbb {n} }f_{k}}
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4cb8186e3eaa5111d7e76c1f7547b1657fa5d7d5
we can show that this is equivalent to
we can show that this is equivalent to requiring that the pre-image of any borel subset of r be in x. the set of measurable functions is closed under algebraic operations, but more importantly it is closed under various kinds of point-wise sequential limits:
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49353281f466b91db13d3be5795cf186151a9dcd
{ x ∣ f (x) > t }
{ x ∣ f (x) > t } ∈ x ∀ t ∈ r. {\displaystyle \{x\,\mid \,f(x)>t\}\in x\quad \forall t\in \mathbb {r}.}
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38f808478b749fe21ea2debf2f37331e2a56a87a
for example, e can be euclidean n -space
for example, e can be euclidean n -space r or some lebesgue measurable subset of it, x is the σ-algebra of all lebesgue measurable subsets of e, and μ is the lebesgue measure. in the mathematical theory of probability, we confine our study to a probability measure μ, which satisfies μ (e) = 1.
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892a1d92c148a14a24470ea875a65f66f5a7a9ae
in the development of the theory in most
in the development of the theory in most modern textbooks (after 1950), the approach to measure and integration is axiomatic. this means that a measure is any function μ defined on a certain class x of subsets of a set e, which satisfies a certain list of properties. these properties can be shown to hold in many differ...
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2e796c6c94d23e75f6283a2a3c7cd620477c3834
the riemann integral uses the notion of length
the riemann integral uses the notion of length explicitly. indeed, the element of calculation for the riemann integral is the rectangle ×, whose area is calculated to be (b − a)(d − c). the quantity b − a is the length of the base of the rectangle and d − c is the height of the rectangle. riemann could only use planar ...
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8f6b71ae5787c1006682ea69d9838912033ab69d
measure theory was initially created to provide a
measure theory was initially created to provide a useful abstraction of the notion of length of subsets of the real line—and, more generally, area and volume of subsets of euclidean spaces. in particular, it provided a systematic answer to the question of which subsets of r have a length. as later set theory developmen...
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