id
stringlengths
40
40
title
stringlengths
15
120
text
stringlengths
41
3.14k
source
stringclasses
2 values
e75ea9f467aa67f4cad7d094356d2ce2c1dafd2d
edward lavern "eddie" johnstone is a canadian former
edward lavern "eddie" johnstone is a canadian former professional ice hockey player. he played for the michigan stags/baltimore blades in the world hockey association (wha), followed by parts of ten seasons in the national hockey league (nhl) with the new york rangers and detroit red wings. he featured in the 1979 stan...
wikipedia
a8565cf7d295bbc7fc07730c078d54f61ef20d78
johnstone played major junior with the medicine hat
johnstone played major junior with the medicine hat tigers of the western canada hockey league from 1971 to 1974. after two consecutive 100 point seasons with medicine hat, johnstone was drafted 104th overall by the new york rangers in the 1974 nhl amateur draft, and 78th overall by the michigan stags in the 1974 wha a...
wikipedia
6af3ed03964a0c15462547a9267130d0437d809a
edward lavern "eddie" johnstone (born march 2, 1954)
edward lavern "eddie" johnstone (born march 2, 1954) is a canadian former professional ice hockey player. he played for the michigan stags/baltimore blades in the world hockey association (wha), followed by parts of ten seasons in the national hockey league (nhl) with the new york rangers and detroit red wings. he feat...
wikipedia
fa385bca0df8467c8d07e72cbfbf2625d723e66f
f-atpase, also known as f-type atpase, is an
f-atpase, also known as f-type atpase, is an atpase/synthase found in bacterial plasma membranes, in mitochondrial inner membranes (in oxidative phosphorylation, where it is known as complex v), and in chloroplast thylakoid membranes. it uses a proton gradient to drive atp synthesis by allowing the passive flux of prot...
wikipedia
1df964623cfbc5d36a8bcc48545c624dbe17c949
the f1, which is peripheral (on the side
the f1, which is peripheral (on the side of the membrane that the protons are moving into). f1 is composed of 5 polypeptide units α3β3γδε that bind to the surface of the fo domain. f-atpases usually work as atp synthases instead of atpases in cellular environments. that is to say, it usually makes atp from the proton g...
wikipedia
f0bd3f8d3732ed640a0467ef929b2eaa24baba37
n-atpases are a group of f-type atpases without
n-atpases are a group of f-type atpases without a delta/oscp subunit, found in bacteria and a group of archaea via horizontal gene transfer. they transport sodium ions instead of protons and tend to hydrolyze atp. they form a distinct group that is further apart from usual f-atpases than a-atpases are from v-atpases.
wikipedia
7b42ddb5e7d5cdd9a16eb2630af5bdc27c2d55ec
the bovine mitochondrial f -atpase complexed with the
the bovine mitochondrial f -atpase complexed with the inhibitor protein if1 is commonly cited in the relevant literature. examples of its use may be found in many cellular fundamental metabolic activities such as acidosis and alkalosis and respiratory gas exchange.
wikipedia
1f2c67e8030b6d1aa84fd9d838ad6286f9845a22
f -f particles are mainly formed of polypeptides.
f -f particles are mainly formed of polypeptides. the f -particle contains 5 types of polypeptides, with the composition-ratio—3α:3β:1δ:1γ:1ε. the f has the 1a:2b:12c composition. together they form a rotary motor. as the protons bind to the subunits of the f domains, they cause parts of it to rotate. this rotation is ...
wikipedia
6587237485ba9419cde5d9596da32b8326fd2179
f-atpases usually work as atp synthases instead of
f-atpases usually work as atp synthases instead of atpases in cellular environments. that is to say, it usually makes atp from the proton gradient instead of working in the other direction like v-atpases typically do. they do occasionally revert as atpases in bacteria.
wikipedia
ef448de016f6fa64d20f96169dda16e25c773b07
f-atpase, also known as f-type atpase, is an
f-atpase, also known as f-type atpase, is an atpase / synthase found in bacterial plasma membranes, in mitochondrial inner membranes (in oxidative phosphorylation, where it is known as complex v), and in chloroplast thylakoid membranes. it uses a proton gradient to drive atp synthesis by allowing the passive flux of pr...
wikipedia
86cce9af79b124ec0c63aba4ac9d1c8ed1201456
the hahn–banach theorem is a central tool in
the hahn–banach theorem is a central tool in functional analysis. it allows the extension of bounded linear functionals defined on a vector subspace of some vector space to the whole space, and it also shows that there are "enough" continuous linear functionals defined on every normed vector space to make the study of ...
wikipedia
5a6a61c118a104e3241f040179496d424d5e951b
for separable banach spaces, d. k. brown and
for separable banach spaces, d. k. brown and s. g. simpson proved that the hahn–banach theorem follows from wkl, a weak subsystem of second-order arithmetic that takes a form of kőnig's lemma restricted to binary trees as an axiom. in fact, they prove that under a weak set of assumptions, the two are equivalent, an exa...
wikipedia
2aef069e7feb291372d933c81a4edaa213c8451b
the ultrafilter lemma is equivalent (under zf) to
the ultrafilter lemma is equivalent (under zf) to the banach–alaoglu theorem, which is another foundational theorem in functional analysis. although the banach–alaoglu theorem implies hb, it is not equivalent to it (said differently, the banach–alaoglu theorem is strictly stronger than hb). however, hb is equivalent to...
wikipedia
a7ec5ae924211fd40f5639b7851c39a1e1c05fe7
the proof of the hahn–banach theorem for real
the proof of the hahn–banach theorem for real vector spaces (hb) commonly uses zorn's lemma, which in the axiomatic framework of zermelo–fraenkel set theory (zf) is equivalent to the axiom of choice (ac). it was discovered by Łoś and ryll-nardzewski and independently by luxemburg that hb can be proved using the ultrafi...
wikipedia
8801b8e32fc55386d5fdca89c79d076c7ee355fc
a vector subspace m of a tvs x
a vector subspace m of a tvs x has the separation property if for every element of x such that x ∉ m, {\displaystyle x\not \in m,} there exists a continuous linear functional f {\displaystyle f} on x such that f (x) ≠ 0 {\displaystyle f(x)\neq 0} and f (m) = 0 {\displaystyle f(m)=0} for all m ∈ m. {\displaystyle m\in m...
wikipedia
c325ee7c81f63ac373d86cd7fe1f6266a52d950d
the hahn–banach theorem guarantees that every hausdorff locally
the hahn–banach theorem guarantees that every hausdorff locally convex space has the hbep. for complete metrizable topological vector spaces there is a converse, due to kalton: every complete metrizable tvs with the hahn–banach extension property is locally convex. on the other hand, a vector space x of uncountable dim...
wikipedia
69c0279ace759d3e00d5f0cdff270fca5cd62191
let x be a topological vector space. a
let x be a topological vector space. a vector subspace m of x has the extension property if any continuous linear functional on m can be extended to a continuous linear functional on x, and we say that x has the hahn–banach extension property (hbep) if every vector subspace of x has the extension property.
wikipedia
49f43036ec7906438be08d3bff8db9a007224de6
for all positive integers n {\displaystyle n} and
for all positive integers n {\displaystyle n} and all finite sequences a 1, …, a n {\displaystyle a_{1},\ldots,a_{n}} of scalars and elements s 1, …, s n {\displaystyle s_{1},\ldots,s_{n}} of s. {\displaystyle s.}
wikipedia
447ee05b46cc0216d9ae2aac2515099b50b4e1ba
theorem (the extension principle) — let f {\displaystyle
theorem (the extension principle) — let f {\displaystyle f} a scalar-valued function on a subset s {\displaystyle s} of a topological vector space x. {\displaystyle x.} then there exists a continuous linear functional f {\displaystyle f} on x {\displaystyle x} extending f {\displaystyle f} if and only if there exists a...
wikipedia
3baa654eb64551cd0987f99adb7770fe17578d64
mazur–orlicz theorem — let p: x → r
mazur–orlicz theorem — let p: x → r {\displaystyle p:x\to \mathbb {r} } be a sublinear function on a real or complex vector space x, {\displaystyle x,} let t {\displaystyle t} be any set, and let r: t → r {\displaystyle r:t\to \mathbb {r} } and v: t → x {\displaystyle v:t\to x} be any maps. the following statements are...
wikipedia
dea59d322ed0c8ec8b7a583396384b216442f73b
an invariant hahn–banach theorem — suppose Γ {\displaystyle
an invariant hahn–banach theorem — suppose Γ {\displaystyle \gamma } is a commutative set of continuous linear maps from a normed space x {\displaystyle x} into itself and let f {\displaystyle f} be a continuous linear functional defined some vector subspace m {\displaystyle m} of x {\displaystyle x} that is Γ {\displa...
wikipedia
2313b5f20886a79b9d549b626b6e91c45aef62b9
a set Γ {\displaystyle \gamma } of maps
a set Γ {\displaystyle \gamma } of maps x → x {\displaystyle x\to x} is commutative (with respect to function composition ∘ {\displaystyle \,\circ \,}) if f ∘ g = g ∘ f {\displaystyle f\circ g=g\circ f} for all f, g ∈ Γ. {\displaystyle f,g\in \gamma.} say that a function f {\displaystyle f} defined on a subset m {\disp...
wikipedia
8611f2ed32a4c29beb2ca99b1b265537aadc307e
vector–valued hahn–banach theorem — if x {\displaystyle x}
vector–valued hahn–banach theorem — if x {\displaystyle x} and y {\displaystyle y} are vector spaces over the same field and if f: m → y {\displaystyle f:m\to y} is a linear map defined on a vector subspace m {\displaystyle m} of x, {\displaystyle x,} then there exists a linear map f: x → y {\displaystyle f:x\to y} tha...
wikipedia
e7821dd1b9f16a8ccdc51de198ae9734fb658cea
if s = { s } {\displaystyle s=\{s\}}
if s = { s } {\displaystyle s=\{s\}} is a singleton set (where s ∈ x {\displaystyle s\in x} is some vector) and if f: x → r {\displaystyle f:x\to \mathbb {r} } is such a maximal dominated linear extension of f: m → r, {\displaystyle f:m\to \mathbb {r},} then f (s) = inf m ∈ m. {\displaystyle f(s)=\inf _{m\in m}.}
wikipedia
5d4364161279b679a0c3880d49a5254ba031d346
theorem (andenaes, 1970) — let p: x →
theorem (andenaes, 1970) — let p: x → r {\displaystyle p:x\to \mathbb {r} } be a sublinear function on a real vector space x, {\displaystyle x,} let f: m → r {\displaystyle f:m\to \mathbb {r} } be a linear functional on a vector subspace m {\displaystyle m} of x {\displaystyle x} such that f ≤ p {\displaystyle f\leq p}...
wikipedia
b828b4fd769f9d2d6d5de31aeaa40498d3618a51
then there exists a linear functional f: x
then there exists a linear functional f: x → r {\displaystyle f:x\to \mathbb {r} } on x {\displaystyle x} such that f ≤ p {\displaystyle f\leq p} on x {\displaystyle x} and f ≤ f ≤ p {\displaystyle f\leq f\leq p} on s. {\displaystyle s.}
wikipedia
8556faab88d18b93ce146eabc181c1302f689e37
hahn–banach sandwich theorem — let p: x →
hahn–banach sandwich theorem — let p: x → r {\displaystyle p:x\to \mathbb {r} } be a sublinear function on a real vector space x, {\displaystyle x,} let s ⊆ x {\displaystyle s\subseteq x} be any subset of x, {\displaystyle x,} and let f: s → r {\displaystyle f:s\to \mathbb {r} } be any map. if there exist positive real...
wikipedia
b1b2b5f7db8856f0187c9c2bd2a4d87956602c67
so for example, suppose that f {\displaystyle f}
so for example, suppose that f {\displaystyle f} is a bounded linear functional defined on a vector subspace m {\displaystyle m} of a normed space x, {\displaystyle x,} so its the operator norm ‖ f ‖ {\displaystyle \|f\|} is a non-negative real number. then the linear functional's absolute value p:= | f | {\displaystyl...
wikipedia
9dfe83bf12f9fcf914dc679218410846a771a8f4
let s {\displaystyle s} be the convex hull
let s {\displaystyle s} be the convex hull of { m ∈ m: p (m) ≤ 1 } ∪ { x ∈ x: q (x) ≤ 1 }. {\displaystyle \{m\in m:p(m)\leq 1\}\cup \{x\in x:q(x)\leq 1\}.} because s {\displaystyle s} is an absorbing disk in x, {\displaystyle x,} its minkowski functional p {\displaystyle p} is a seminorm. then p = p {\displaystyle p=p}...
wikipedia
bbdc920999a087c58e070b0cea44fbea512f8b73
hahn–banach theorem for seminorms — if p: m
hahn–banach theorem for seminorms — if p: m → r {\displaystyle p:m\to \mathbb {r} } is a seminorm defined on a vector subspace m {\displaystyle m} of x, {\displaystyle x,} and if q: x → r {\displaystyle q:x\to \mathbb {r} } is a seminorm on x {\displaystyle x} such that p ≤ q | m, {\displaystyle p\leq q{\big \vert }_{m...
wikipedia
7305d902769f4a43050b338ce4d8655c42bd7ba9
theorem — if d {\displaystyle d} is an
theorem — if d {\displaystyle d} is an absorbing disk in a real or complex vector space x {\displaystyle x} and if f {\displaystyle f} be a linear functional defined on a vector subspace m {\displaystyle m} of x {\displaystyle x} such that | f | ≤ 1 {\displaystyle |f|\leq 1} on m ∩ d, {\displaystyle m\cap d,} then ther...
wikipedia
277d57c38f4646dc3ed05f551e33c3f078e07bfb
the above result may be used to show
the above result may be used to show that every closed vector subspace of r n {\displaystyle \mathbb {r} ^{\mathbb {n} }} is complemented because any such space is either finite dimensional or else tvs–isomorphic to r n. {\displaystyle \mathbb {r} ^{\mathbb {n} }.}
wikipedia
dd5c2093c4b0f25d1dc47f2d33fd8874141563e9
since k i {\displaystyle \mathbf {k} ^{i}} is
since k i {\displaystyle \mathbf {k} ^{i}} is a complete tvs so is y, {\displaystyle y,} and since any complete subset of a hausdorff tvs is closed, y {\displaystyle y} is a closed subset of x. {\displaystyle x.} let f = (f i) i ∈ i: y → k i {\displaystyle f=\left(f_{i}\right)_{i\in i}:y\to \mathbf {k} ^{i}} be a tvs i...
wikipedia
3ff6b46b40362fa272b1416cae2df0e79fffc7ab
since k i {\displaystyle \mathbf {k} ^{i}} is
circ f:x\to y,} which is a continuous linear map whose restriction to y {\displaystyle y} is p | y = f − 1 ∘ f | y = f − 1 ∘ f = 1 y, {\displaystyle p{\big \vert }_{y}=f^{-1}\circ f{\big \vert }_{y}=f^{-1}\circ f=\mathbf {1} _{y},} where 1 y {\displaystyle \mathbb {1} _{y}} denotes the identity map on y. {\displaystyle...
wikipedia
c95502bac4a2b81c220ecccba3bf19a1cb8218e8
proposition — suppose x {\displaystyle x} is a
proposition — suppose x {\displaystyle x} is a hausdorff locally convex tvs over the field k {\displaystyle \mathbf {k} } and y {\displaystyle y} is a vector subspace of x {\displaystyle x} that is tvs–isomorphic to k i {\displaystyle \mathbf {k} ^{i}} for some set i. {\displaystyle i.} then y {\displaystyle y} is a cl...
wikipedia
fec3f4f47ccd28384520c2c80beb72747d4b67cf
the hahn–banach theorem is often useful when one
the hahn–banach theorem is often useful when one wishes to apply the method of a priori estimates. suppose that we wish to solve the linear differential equation p u = f {\displaystyle pu=f} for u, {\displaystyle u,} with f {\displaystyle f} given in some banach space x. if we have control on the size of u {\displaysty...
wikipedia
bbd06a8ca8253543311970278af83b569659b2ef
that last result also suggests that the hahn–banach
that last result also suggests that the hahn–banach theorem can often be used to locate a "nicer" topology in which to work. for example, many results in functional analysis assume that a space is hausdorff or locally convex. however, suppose x is a topological vector space, not necessarily hausdorff or locally convex,...
wikipedia
ccfe1ff6fdf019fec3f4bd7aeeac22ce53c535da
for example, linear subspaces are characterized by functionals:
for example, linear subspaces are characterized by functionals: if x is a normed vector space with linear subspace m (not necessarily closed) and if z {\displaystyle z} is an element of x not in the closure of m, then there exists a continuous linear map f: x → k {\displaystyle f:x\to \mathbf {k} } with f (m) = 0 {\dis...
wikipedia
1cbcadbff03c10abfdd70c43fb04b5c603883041
let u {\displaystyle u} be a convex balanced
let u {\displaystyle u} be a convex balanced neighborhood of the origin in a locally convex topological vector space x {\displaystyle x} and suppose x ∈ x {\displaystyle x\in x} is not an element of u. {\displaystyle u.} then there exists a continuous linear functional f {\displaystyle f} on x {\displaystyle x} such th...
wikipedia
604edd0ff3abcdbe2798caa32372a9052c915466
call a normed space x {\displaystyle x} smooth
call a normed space x {\displaystyle x} smooth if at each point x {\displaystyle x} in its unit ball there exists a unique closed hyperplane to the unit ball at x. {\displaystyle x.} köthe showed in 1983 that a normed space is smooth at a point x {\displaystyle x} if and only if the norm is gateaux differentiable at th...
wikipedia
f5f3a56d61cdc460f3966c6f546b45adf2a37f97
since points are trivially convex, geometric hahn–banach implies
since points are trivially convex, geometric hahn–banach implies that functionals can detect the boundary of a set. in particular, let x {\displaystyle x} be a real topological vector space and a ⊆ x {\displaystyle a\subseteq x} be convex with int a ≠ ∅. {\displaystyle \operatorname {int} a\neq \varnothing.} if a 0 ∈ a...
wikipedia
e6ebb6b00b032a91ff1509fb3a311633893bc369
corollary (separation of a subspace and an open
corollary (separation of a subspace and an open convex set) — let m {\displaystyle m} be a vector subspace of a locally convex topological vector space x, {\displaystyle x,} and u {\displaystyle u} be a non-empty open convex subset disjoint from m. {\displaystyle m.} then there exists a continuous linear functional f {...
wikipedia
6ce6a7f2912075e91d50461641e9b74a19ec8e68
theorem (mazur) — let m {\displaystyle m} be
theorem (mazur) — let m {\displaystyle m} be a vector subspace of the topological vector space x {\displaystyle x} and suppose k {\displaystyle k} is a non-empty convex open subset of x {\displaystyle x} with k ∩ m = ∅. {\displaystyle k\cap m=\varnothing.} then there is a closed hyperplane (codimension-1 vector subspac...
wikipedia
89c1396f36fcb626ad36bb0b5c6f55dc2c88394a
then following important corollary is known as the
then following important corollary is known as the geometric hahn–banach theorem or mazur's theorem (also known as ascoli–mazur theorem). it follows from the first bullet above and the convexity of m. {\displaystyle m.}
wikipedia
94b97b5a16fd0b70f36a9eed64dd7dac6dae53c1
theorem — let a {\displaystyle a} and b
theorem — let a {\displaystyle a} and b {\displaystyle b} be non-empty convex subsets of a real locally convex topological vector space x. {\displaystyle x.} if int a ≠ ∅ {\displaystyle \operatorname {int} a\neq \varnothing } and b ∩ int a = ∅ {\displaystyle b\cap \operatorname {int} a=\varnothing } then there exists a...
wikipedia
240dc8e37edb13542aa92e3449954ff70df1ae48
the key element of the hahn–banach theorem is
the key element of the hahn–banach theorem is fundamentally a result about the separation of two convex sets: { − p (− x − n) − f (n): n ∈ m }, {\displaystyle \{-p(-x-n)-f(n):n\in m\},} and { p (m + x) − f (m): m ∈ m }. {\displaystyle \{p(m+x)-f(m):m\in m\}.} this sort of argument appears widely in convex geometry, opt...
wikipedia
9b93a8bf2b3a54b4d3dfbae40d652ad783301cae
if the tvs x {\displaystyle x} is not
if the tvs x {\displaystyle x} is not locally convex then there might not exist any continuous seminorm p: x → r {\displaystyle p:x\to \mathbb {r} } defined on x {\displaystyle x} (not just on m {\displaystyle m}) that dominates f, {\displaystyle f,} in which case the hahn–banach theorem can not be applied as it was in...
wikipedia
f7fe9c67d299fc5f7e1866c678d8c328f9feb931
the continuous extension theorem might fail if the
the continuous extension theorem might fail if the topological vector space (tvs) x {\displaystyle x} is not locally convex. for example, for 0 < p < 1, {\displaystyle 0<p<1,} the lebesgue space l p () {\displaystyle l^{p}()} is a complete metrizable tvs (an f-space) that is not locally convex (in fact, its only convex...
wikipedia
838951846c9ff20267cd0b8096cebca4fe78b46c
let f {\displaystyle f} be a continuous linear
let f {\displaystyle f} be a continuous linear functional defined on a vector subspace m {\displaystyle m} of a normed space x. {\displaystyle x.} then the function p: x → r {\displaystyle p:x\to \mathbb {r} } defined by p (x) = ‖ f ‖ ‖ x ‖ {\displaystyle p(x)=\|f\|\,\|x\|} is a seminorm on x {\displaystyle x} that dom...
wikipedia
80f619d91dc451b1e1b0d681282b0cca0b5bf708
applying the hahn–banach theorem to f {\displaystyle f}
applying the hahn–banach theorem to f {\displaystyle f} with this seminorm ‖ f ‖ ‖ ⋅ ‖ {\displaystyle \|f\|\,\|\cdot \|} thus produces a dominated linear extension whose norm is (necessarily) equal to that of f, {\displaystyle f,} which proves the theorem:
wikipedia
e3ea41df9328549723522320033aa9ced5d05369
is finite, in which case | f (m)
is finite, in which case | f (m) | ≤ ‖ f ‖ ‖ m ‖ {\displaystyle |f(m)|\leq \|f\|\|m\|} holds for every point m {\displaystyle m} in its domain. moreover, if c ≥ 0 {\displaystyle c\geq 0} is such that | f (m) | ≤ c ‖ m ‖ {\displaystyle |f(m)|\leq c\|m\|} for all m {\displaystyle m} in the functional's domain, then neces...
wikipedia
47e6bd28b493129f9365b8f137290a9a4c9d9fb7
let f {\displaystyle f} be a continuous linear
let f {\displaystyle f} be a continuous linear functional defined on a vector subspace m {\displaystyle m} of a locally convex topological vector space x. {\displaystyle x.} because x {\displaystyle x} is locally convex, there exists a continuous seminorm p: x → r {\displaystyle p:x\to \mathbb {r} } on x {\displaystyle...
wikipedia
a99c4cd0b2e69861f3776973562acd8e662316d9
the absolute value of a linear functional is
the absolute value of a linear functional is always a seminorm. a linear functional f {\displaystyle f} on a topological vector space x {\displaystyle x} is continuous if and only if its absolute value | f | {\displaystyle |f|} is continuous, which happens if and only if there exists a continuous seminorm p {\displayst...
wikipedia
f2f89dc50e2f9a824c2bdc734b95c72704b7e878
norm-preserving hahn–banach continuous extension theorem — every continuous
norm-preserving hahn–banach continuous extension theorem — every continuous linear functional f {\displaystyle f} defined on a vector subspace m {\displaystyle m} of a (real or complex) normed space x {\displaystyle x} has a continuous linear extension f {\displaystyle f} to all of x {\displaystyle x} that satisfies ‖ ...
wikipedia
6571ecac475d808be7042fd19631a4574e11fcc0
on a normed (or seminormed) space, a linear
on a normed (or seminormed) space, a linear extension f {\displaystyle f} of a bounded linear functional f {\displaystyle f} is said to be norm-preserving if it has the same dual norm as the original functional: ‖ f ‖ = ‖ f ‖. {\displaystyle \|f\|=\|f\|.} because of this terminology, the second part of the above theore...
wikipedia
61447022d648bac39673579546cfddbce4c59d5f
hahn–banach continuous extension theorem — every continuous linear
hahn–banach continuous extension theorem — every continuous linear functional f {\displaystyle f} defined on a vector subspace m {\displaystyle m} of a (real or complex) locally convex topological vector space x {\displaystyle x} has a continuous linear extension f {\displaystyle f} to all of x. {\displaystyle x.} if i...
wikipedia
f39a73346ec2b305eb8015cffe4a203115b62bab
when m {\displaystyle m} has countable codimension, then
when m {\displaystyle m} has countable codimension, then using induction and the lemma completes the proof of the hahn–banach theorem. the standard proof of the general case uses zorn's lemma although the strictly weaker ultrafilter lemma (which is equivalent to the compactness theorem and to the boolean prime ideal th...
wikipedia
4e0ff552a7ceeefad578772f84013dcd15a08f51
the set of all possible dominated linear extensions
the set of all possible dominated linear extensions of f {\displaystyle f} are partially ordered by extension of each other, so there is a maximal extension f. {\displaystyle f.} by the codimension-1 result, if f {\displaystyle f} is not defined on all of x, {\displaystyle x,} then it can be further extended. thus f {\...
wikipedia
e04c479635e95ae872c2a5e8e1be97a710a78948
if r > 0 {\displaystyle r>0} (respectively, if
if r > 0 {\displaystyle r>0} (respectively, if r < 0 {\displaystyle r<0}) then the right (respectively, the left) hand side equals 1 r {\displaystyle {\tfrac {1}{r}}\left} so that multiplying by r {\displaystyle r} gives r b ≤ p (m + r x) − f (m). {\displaystyle rb\leq p(m+rx)-f(m).} ◼ {\displaystyle \blacksquare }
wikipedia
3c6b4772eb2f6c6e5d9854c627d6506eecb0a461
to see that f (m) + r b
to see that f (m) + r b ≤ p (m + r x) {\displaystyle f(m)+rb\leq p(m+rx)} follows, assume r ≠ 0 {\displaystyle r\neq 0} and substitute 1 r m {\displaystyle {\tfrac {1}{r}}m} in for both m {\displaystyle m} and n {\displaystyle n} to obtain
wikipedia
54f075bf2d06636723aea3b96fe63f1d86cf2c1e
where a ≤ c {\displaystyle a\leq c} are
where a ≤ c {\displaystyle a\leq c} are real numbers. to guarantee f b ≤ p, {\displaystyle f_{b}\leq p,} it suffices that a ≤ b ≤ c {\displaystyle a\leq b\leq c} (in fact, this is also necessary) because then b {\displaystyle b} satisfies "the decisive inequality"
wikipedia
6366441b0c05894f62798979908bb4bba3c9d1bc
given any real number b, {\displaystyle b,} the
given any real number b, {\displaystyle b,} the map f b: m ⊕ r x → r {\displaystyle f_{b}:m\oplus \mathbb {r} x\to \mathbb {r} } defined by f b (m + r x) = f (m) + r b {\displaystyle f_{b}(m+rx)=f(m)+rb} is always a linear extension of f {\displaystyle f} to m ⊕ r x {\displaystyle m\oplus \mathbb {r} x} but it might no...
wikipedia
e7be7a52cb782ff2dcfd115c7116480ff3e2b159
lemma (one–dimensional dominated extension theorem) — let p:
lemma (one–dimensional dominated extension theorem) — let p: x → r {\displaystyle p:x\to \mathbb {r} } be a sublinear function on a real vector space x, {\displaystyle x,} let f: m → r {\displaystyle f:m\to \mathbb {r} } a linear functional on a proper vector subspace m ⊊ x {\displaystyle m\subsetneq x} such that f ≤ p...
wikipedia
9c9a17fa4c0580e14954d7712383de9b441f7ae9
the hahn–banach theorem for real vector spaces ultimately
the hahn–banach theorem for real vector spaces ultimately follows from helly's initial result for the special case where the linear functional is extended from m {\displaystyle m} to a larger vector space in which m {\displaystyle m} has codimension 1. {\displaystyle 1.}
wikipedia
3005afdaec44fc804523e8b0383183ce2178490f
a linear functional f {\displaystyle f} on a
a linear functional f {\displaystyle f} on a topological vector space is continuous if and only if this is true of its real part re f; {\displaystyle \operatorname {re} f;} if the domain is a normed space then ‖ f ‖ = ‖ re f ‖ {\displaystyle \|f\|=\|\operatorname {re} f\|} (where one side is infinite if and only if the...
wikipedia
985e97dec23e43cfcd09de218daef516cfb538ea
the proof above shows that when p {\displaystyle
the proof above shows that when p {\displaystyle p} is a seminorm then there is a one-to-one correspondence between dominated linear extensions of f: m → c {\displaystyle f:m\to \mathbb {c} } and dominated real-linear extensions of re f: m → r; {\displaystyle \operatorname {re} f:m\to \mathbb {r} ;} the proof even give...
wikipedia
1f319b8602908b8f24ca03c2334ca5190ebbf86b
suppose p: x → r {\displaystyle p:x\to \mathbb
suppose p: x → r {\displaystyle p:x\to \mathbb {r} } is a seminorm on a complex vector space x {\displaystyle x} and let f: m → c {\displaystyle f:m\to \mathbb {c} } be a linear functional defined on a vector subspace m {\displaystyle m} of x {\displaystyle x} that satisfies | f | ≤ p {\displaystyle |f|\leq p} on m. {\...
wikipedia
35753f96586e0a22f0b4769a8fa6f5e87ee7e1c5
if f {\displaystyle f} is a linear functional
if f {\displaystyle f} is a linear functional on a (complex or real) vector space x {\displaystyle x} and if p: x → r {\displaystyle p:x\to \mathbb {r} } is a seminorm then
wikipedia
137c050de57bc3972053cad43ac746f32bc8b759
and moreover, if ‖ ⋅ ‖ {\displaystyle \|\cdot
and moreover, if ‖ ⋅ ‖ {\displaystyle \|\cdot \|} is a norm on x {\displaystyle x} then their dual norms are equal: ‖ f ‖ = ‖ re f ‖. {\displaystyle \|f\|=\|\operatorname {re} f\|.} in particular, a linear functional on x {\displaystyle x} extends another one defined on m ⊆ x {\displaystyle m\subseteq x} if and only if...
wikipedia
4c7f11b73f93a3e5c67d7f9cc8f5f6df2ad16d84
every linear functional f: x → c {\displaystyle
every linear functional f: x → c {\displaystyle f:x\to \mathbb {c} } on a complex vector space is completely determined by its real part re f: x → r {\displaystyle \;\operatorname {re} f:x\to \mathbb {r} \;} through the formula
wikipedia
cbbbada3f254757ee06417752cdc6135fc311e72
a complex-valued functional f {\displaystyle f} is said
a complex-valued functional f {\displaystyle f} is said to be dominated by p {\displaystyle p} if | f (x) | ≤ p (x) {\displaystyle |f(x)|\leq p(x)} for all x {\displaystyle x} in the domain of f. {\displaystyle f.} with this terminology, the above statements of the hahn–banach theorem can be restated more succinctly:
wikipedia
bb1547209ed254ab1ed9bbd890493a75d0ef4cf7
this condition holds if and only if p
this condition holds if and only if p {\displaystyle p} is a convex and balanced function satisfying p (0) ≤ 0, {\displaystyle p(0)\leq 0,} or equivalently, if and only if it is convex, satisfies p (0) ≤ 0, {\displaystyle p(0)\leq 0,} and p (u x) ≤ p (x) {\displaystyle p(ux)\leq p(x)} for all x ∈ x {\displaystyle x\in ...
wikipedia
5437036cae97f6b2e4c1c790afe46c44a95cc39c
the theorem remains true if the requirements on
the theorem remains true if the requirements on p {\displaystyle p} are relaxed to require only that for all x, y ∈ x {\displaystyle x,y\in x} and all scalars a {\displaystyle a} and b {\displaystyle b} satisfying | a | + | b | ≤ 1, {\displaystyle |a|+|b|\leq 1,}
wikipedia
378202c89943ec6274dfdbfb09c45994b01adc3f
hahn–banach theorem — suppose p: x → r
hahn–banach theorem — suppose p: x → r {\displaystyle p:x\to \mathbb {r} } a seminorm on a vector space x {\displaystyle x} over the field k, {\displaystyle \mathbf {k},} which is either r {\displaystyle \mathbb {r} } or c. {\displaystyle \mathbb {c}.} if f: m → k {\displaystyle f:m\to \mathbf {k} } is a linear functio...
wikipedia
b0bb761b4362545b301e4dd42469e589294efe66
which is the (equivalent) conclusion that some authors
which is the (equivalent) conclusion that some authors write instead of f ≤ p. {\displaystyle f\leq p.} it follows that if p: x → r {\displaystyle p:x\to \mathbb {r} } is also symmetric, meaning that p (− x) = p (x) {\displaystyle p(-x)=p(x)} holds for all x ∈ x, {\displaystyle x\in x,} then f ≤ p {\displaystyle f\leq ...
wikipedia
ae5d8b06f492d7cec33f53e467597f68bf793d28
a function p: x → r {\displaystyle p:x\to
a function p: x → r {\displaystyle p:x\to \mathbb {r} } is convex and satisfies p (0) ≤ 0 {\displaystyle p(0)\leq 0} if and only if p (a x + b y) ≤ a p (x) + b p (y) {\displaystyle p(ax+by)\leq ap(x)+bp(y)} for all vectors x, y ∈ x {\displaystyle x,y\in x} and all non-negative real a, b ≥ 0 {\displaystyle a,b\geq 0} su...
wikipedia
1c7c618630e05f3def8be539bd8a5e8438bc0553
a function p: x → r {\displaystyle p:x\to
_{t>0}{\frac {p(trx)}{tr}}=r\inf _{\tau >0}{\frac {p(\tau x)}{\tau }}=rp_{0}(x)}), hence, being convex, it is sublinear. it is also bounded above by p 0 ≤ p, {\displaystyle p_{0}\leq p,} and satisfies f ≤ p 0 {\displaystyle f\leq p_{0}} for every linear functional f ≤ p. {\displaystyle f\leq p.} so the extension of th...
wikipedia
f6c65392a8191b63f72b6c25947a21edc467a1b8
moreover, if p {\displaystyle p} is a seminorm
moreover, if p {\displaystyle p} is a seminorm then | f (x) | ≤ p (x) {\displaystyle |f(x)|\leq p(x)} necessarily holds for all x ∈ x. {\displaystyle x\in x.}
wikipedia
5d4d3fd33fd41a6ea0767b045080a3877a358c2c
hahn–banach dominated extension theorem (for real linear functionals)
hahn–banach dominated extension theorem (for real linear functionals) — if p: x → r {\displaystyle p:x\to \mathbb {r} } is a sublinear function (such as a norm or seminorm for example) defined on a real vector space x {\displaystyle x} then any linear functional defined on a vector subspace of x {\displaystyle x} that ...
wikipedia
ef2f6ac75d54a198e8fad03d676929fbe8c42174
a real-valued function f: m → r {\displaystyle
a real-valued function f: m → r {\displaystyle f:m\to \mathbb {r} } defined on a subset m {\displaystyle m} of x {\displaystyle x} is said to be dominated (above) by a function p: x → r {\displaystyle p:x\to \mathbb {r} } if f (m) ≤ p (m) {\displaystyle f(m)\leq p(m)} for every m ∈ m. {\displaystyle m\in m.} hence the ...
wikipedia
eb21e9c440e07efb8e0381418b660d87eb942d5e
there exists a continuous linear functional f {\displaystyle
there exists a continuous linear functional f {\displaystyle f} on x {\displaystyle x} such that f (x i) = c i {\displaystyle f\left(x_{i}\right)=c_{i}} for all i ∈ i {\displaystyle i\in i} if and only if there exists a k > 0 {\displaystyle k>0} such that for any choice of scalars (s i) i ∈ i {\displaystyle \left(s_{i}...
wikipedia
7c8146698a0deaeb7b63997b93965e3f46d18a07
theorem (the functional problem) — let (x i)
theorem (the functional problem) — let (x i) i ∈ i {\displaystyle \left(x_{i}\right)_{i\in i}} be vectors in a real or complex normed space x {\displaystyle x} and let (c i) i ∈ i {\displaystyle \left(c_{i}\right)_{i\in i}} be scalars also indexed by i ≠ ∅. {\displaystyle i\neq \varnothing.}
wikipedia
dc92b076b68ac022d363a303129d62cfcbe83658
riesz went on to define l p ()
riesz went on to define l p () {\displaystyle l^{p}()} space (1 < p < ∞ {\displaystyle 1<p<\infty }) in 1910 and the ℓ p {\displaystyle \ell ^{p}} spaces in 1913. while investigating these spaces he proved a special case of the hahn–banach theorem. helly also proved a special case of the hahn–banach theorem in 1912. in...
wikipedia
449601adbd56e179436513de1f3ac97c00804dac
riesz and helly solved the problem for certain
riesz and helly solved the problem for certain classes of spaces (such as l p () {\displaystyle l^{p}()} and c () {\displaystyle c()}) where they discovered that the existence of a solution was equivalent to the existence and continuity of certain linear functionals. in effect, they needed to solve the following proble...
wikipedia
74983ad90d8099b3531f39135f3378f2713e0494
the hahn–banach theorem arose from attempts to solve
the hahn–banach theorem arose from attempts to solve infinite systems of linear equations. this is needed to solve problems such as the moment problem, whereby given all the potential moments of a function one must determine if a function having these moments exists, and, if so, find it in terms of those moments. anoth...
wikipedia
f46d0353379952e934b16fdf6d3eeea9d612835e
the first hahn–banach theorem was proved by eduard
the first hahn–banach theorem was proved by eduard helly in 1912 who showed that certain linear functionals defined on a subspace of a certain type of normed space (c n {\displaystyle \mathbb {c} ^{\mathbb {n} }}) had an extension of the same norm. helly did this through the technique of first proving that a one-dimens...
wikipedia
2ff95a9615c83c1acc060257e0e1ed85f8bad5d7
the theorem is named for the mathematicians hans
the theorem is named for the mathematicians hans hahn and stefan banach, who proved it independently in the late 1920s. the special case of the theorem for the space c {\displaystyle c} of continuous functions on an interval was proved earlier (in 1912) by eduard helly, and a more general extension theorem, the m. ries...
wikipedia
86cce9af79b124ec0c63aba4ac9d1c8ed1201456
the hahn–banach theorem is a central tool in
the hahn–banach theorem is a central tool in functional analysis. it allows the extension of bounded linear functionals defined on a vector subspace of some vector space to the whole space, and it also shows that there are "enough" continuous linear functionals defined on every normed vector space to make the study of ...
wikipedia
372e3618fcea2e8cadedcb73d0561303d0342f18
gliese 849 b is an extrasolar planet approximately
gliese 849 b is an extrasolar planet approximately 29 light years away in the constellation of aquarius. it is the first long-period jupiter-like planet discovered around a red dwarf, announced in august 2006 by the california and carnegie planet search team using the radial velocity technique. the previously longest-p...
wikipedia
44c7ebc3cdce198ce27e09fb469f0ca31bdd8011
gliese 849 b is an extrasolar planet approximately
gliese 849 b is an extrasolar planet approximately 29 light years away in the constellation of aquarius. it is the first long-period jupiter -like planet discovered around a red dwarf, announced in august 2006 by the california and carnegie planet search team using the radial velocity technique. the previously longest-...
wikipedia
dd92e4cf1ad6cca2293f5d25d864450f9e5a6ddb
the eiserner steg is a footbridge spanning the
the eiserner steg is a footbridge spanning the river main in the city of frankfurt, germany, which connects the centre of frankfurt with the district of sachsenhausen. the first wrought iron bridge was built in 1868. it was replaced in 1911/1912 by a slightly larger cantilever bridge. it is 170 metres long and consists...
wikipedia
4093ce0d2bdeca3f3fa317559ffd26a85d334a77
the first wrought iron bridge was built in
the first wrought iron bridge was built in 1868. it was replaced in 1911/1912 by a slightly larger cantilever bridge. it is 170 metres long and consists of riveted steel trusses with two bridge piers. the bridge was blown up by the wehrmacht in the final days of world war ii, but it was rebuilt shortly afterwards in 19...
wikipedia
83ec44c3c33da2969a7f5bcf3f9196ad404b6d4a
edobashi station opened on january 1, 1917 as
edobashi station opened on january 1, 1917 as a station on the ise railway. the ise railway became the ise electric railway on september 12, 1926, which merged with the sangu express electric railway on september 15, 1936. on march 15, 1941, the sangu express electric railway merged with osaka electric railway to becom...
wikipedia
b38221f698da6ae440832980e47e745e36b019d2
edobashi station (江戸橋駅, edobashi-eki) is a passenger railway
edobashi station (江戸橋駅, edobashi-eki) is a passenger railway station in located in the city of tsu, mie prefecture, japan, operated by the private railway operator kintetsu railway.
wikipedia
578e82c25d9ad8a61b89404bf833b110bbde53bc
frank "pud" glass was a scottish-canadian professional ice
frank "pud" glass was a scottish-canadian professional ice hockey player who played in various professional and amateur leagues, including the national hockey association and eastern canada amateur hockey association. he was a member of the montreal wanderers' stanley cup champion teams in the 1905–06, 1906–07, 1907–08...
wikipedia
82a52b0cd01ca82ec82409dfb4c0d559ce6c66b4
"his work does not show up, and frequently
"his work does not show up, and frequently spectators see little to his play. forwards and defence men on other teams, however, will tell you that glass is one of the hardest players in the game to get past. his checking back through center ice is also of great assistance to the defence."
wikipedia
148b75df731ca5b5fc1618af993af39694da26ef
outside of the left wing position, glass also
outside of the left wing position, glass also played as a rover, the more free-roaming position in the seven man game between defence and the forward line. the march 21, 1908 issue of the ottawa citizen, in a review of the players on the montreal wanderers, claimed that glass' greatest strength as a player was his chec...
wikipedia
ad128366a478e4be279875035e19d2d23e376bef
frank glass grew up in the same neighbourhood
frank glass grew up in the same neighbourhood of pointe-saint-charles in montreal as fellow montreal wanderers player ernie "moose" johnson, and the two were inseparable companions off the ice and also teamed well together on the ice. glass and johnson played together on the 1902–03 montreal st. lawrence team in the mo...
wikipedia
3cd3db9a0646dcaaeec69d4b91f0c54c05fcebe3
he would play for the montreal wanderers for
he would play for the montreal wanderers for seven seasons. in 1906, he became a professional paid player on the wanderers, one of five out of a roster of nine. he first signed a contract with the montreal hockey club, then chose not to report and signed with the wanderers instead for more money. his situation caused a...
wikipedia
6664a736a1c0909acb2f15f6caa322821fcf8162
frank glass was born in broughty ferry, scotland,
frank glass was born in broughty ferry, scotland, but raised in canada. he played hockey in his neighbourhood of pointe-saint-charles in montreal. his first senior team was the montreal wanderers, then an amateur team for the 1904–05 season.
wikipedia