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Cobordism

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In low dimensions, the bordism question is relatively trivial, but the category of cobordism is not. For instance, the disk bounding the circle corresponds to a nullary (0-ary) operation, while the cylinder corresponds to a 1-ary operation and the pair of pants to a binary operation.
7236:{\displaystyle {\begin{aligned}\Omega _{0}^{\text{SO}}&=\mathbb {Z} ,\\\Omega _{1}^{\text{SO}}&=0,\\\Omega _{2}^{\text{SO}}&=0,\\\Omega _{3}^{\text{SO}}&=0,\\\Omega _{4}^{\text{SO}}&=\mathbb {Z} ,\\\Omega _{5}^{\text{SO}}&=\mathbb {Z} _{2}.\end{aligned}}} 7470: 5997: 8525:-dimensional" is to clarify the dimension of all manifolds in question, otherwise it is unclear whether a "5-dimensional cobordism" refers to a 5-dimensional cobordism between 4-dimensional manifolds or a 6-dimensional cobordism between 5-dimensional manifolds. 2216: 6293: 106:
that is closed, i.e., with empty boundary. In general, a closed manifold need not be a boundary: cobordism theory is the study of the difference between all closed manifolds and those that are boundaries. The theory was originally developed by
1944: 3656:). Conversely, given a handle decomposition of a cobordism, it comes from a suitable Morse function. In a suitably normalized setting this process gives a correspondence between handle decompositions and Morse functions on a cobordism. 8136: 8319: 424: 4898: 1517:
are used by some authors interchangeably; others distinguish them. When one wishes to distinguish the study of cobordism classes from the study of cobordisms as objects in their own right, one calls the equivalence question
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There are two possible outcomes, depending on whether our gluing maps have the same or opposite orientation on the two boundary circles. If the orientations are the same (Fig. 2b), the resulting manifold is the
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a "cospan category": it is not the category of all cospans in "the category of manifolds with inclusions on the boundary", but rather a subcategory thereof, as the requirement that
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whose objects are closed manifolds and whose morphisms are cobordisms. Roughly speaking, composition is given by gluing together cobordisms end-to-end: the composition of (
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Cobordisms are studied both for the equivalence relation that they generate, and as objects in their own right. Cobordism is a much coarser equivalence relation than
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Cobordism can also be defined for manifolds that have additional structure, notably an orientation. This is made formal in a general way using the notion of
8207: 5077:{\displaystyle \left\langle w_{i_{1}}(M)\cdots w_{i_{k}}(M),\right\rangle =\left\langle w_{i_{1}}(N)\cdots w_{i_{k}}(N),\right\rangle \in \mathbb {F} _{2}} 334: 6577: 9390: 4291: 8408:)) – while oriented cobordism is a product of Eilenberg–MacLane spectra rationally, and at 2, but not at odd primes: the oriented cobordism spectrum 6789: 1565:
The above is the most basic form of the definition. It is also referred to as unoriented bordism. In many situations, the manifolds in question are
3357: 1878: 2494:{\displaystyle W:=(M\times I)\cup _{\mathbb {S} ^{p}\times \mathbb {D} ^{q}\times \{1\}}\left(\mathbb {D} ^{p+1}\times \mathbb {D} ^{q}\right)} 5672: 1553:
are cobordant if they jointly bound a manifold; i.e., if their disjoint union is a boundary. Further, cobordism groups form an extraordinary
2531: 3711:. It performed an important role, historically speaking, in developments in topology in the 1950s and early 1960s, in particular in the 3524: 7478: 7011:(Wall, 1960). Two oriented manifolds are oriented cobordant if and only if their Stiefel–Whitney and Pontrjagin numbers are the same. 5090: 3838:
whose value on a disjoint union of manifolds is equivalent to the tensor product of its values on each of the constituent manifolds.
8325: 1187: 7733: 7743: 7465:{\displaystyle \sigma \left(\mathbb {P} ^{2i_{1}}(\mathbb {C} )\times \cdots \times \mathbb {P} ^{2i_{k}}(\mathbb {C} )\right)=1.} 6005: 8194: 5782: 3712: 2157: 5992:{\displaystyle \chi \left(\mathbb {P} ^{2i_{1}}(\mathbb {R} )\times \cdots \times \mathbb {P} ^{2i_{k}}(\mathbb {R} )\right)=1.} 3463: 4488: 6881: 5175: 3851: 3589: 3081: 3034: 2842: 2675: 1735: 1724:
Instead of considering additional structure, it is also possible to take into account various notions of manifold, especially
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This is true for unoriented cobordism. Other cobordism theories do not reduce to ordinary homology in this way, notably
1009:. It is a 1-dimensional cobordism between the 0-dimensional manifolds {0}, {1}. More generally, for any closed manifold 208:
cannot be solved – but it is possible to classify manifolds up to cobordism. Cobordisms are central objects of study in
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This shows, for example, that every 3-dimensional closed manifold is the boundary of a 4-manifold (with boundary).
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Those points without a neighborhood homeomorphic to an open subset of Euclidean space are the boundary points of
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In particular such a product of real projective spaces is not null-cobordant. The mod 2 Euler characteristic map
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with the disjoint union as operation. More specifically, if and denote the cobordism classes of the manifolds
9411: 8910: 8822: 8386: 7261: 4674: 4432: 2977:– that is, two disks - and it's clear that the result of doing so is to give us two disjoint spheres. (Fig. 2a) 196:
of manifolds, and is significantly easier to study and compute. It is not possible to classify manifolds up to
6749: 5628: 1433: + 1)-manifold. For example, the circle is null-cobordant since it bounds a disk. More generally, a 9270: 8878: 8719: 8145: 6978: 4365: 3894: 3203:
is a critical value with exactly one critical point in its preimage. If the index of this critical point is
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gives a starting point for calculations. The computation is only easy if the particular cobordism theory
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can be effectively computed once one knows the cobordism theory of a point and the homology of the space
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Oriented cobordism is the one of manifolds with an SO-structure. Equivalently, all manifolds need to be
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The resulting cobordism groups are then defined analogously to the unoriented case. They are denoted by
6325: 6061: 3680:). PoincarĂ© simultaneously defined both homology and cobordism, which are not the same, in general. See 3425: 1441: + 1)-disk. Also, every orientable surface is null-cobordant, because it is the boundary of a 1151: 9278: 8779: 8543: 8333: 1265: 1233: 288: 275: 5242: 4199: 2751: 2722: 8429: 6586: 3677: 1725: 1623: 1587: 116: 8031: 7967: 7337:
It is an oriented cobordism invariant, which is expressed in terms of the Pontrjagin numbers by the
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Cobordisms are objects of study in their own right, apart from cobordism classes. Cobordisms form a
2795:
For surgery on the 2-sphere, there are more possibilities, since we can start by cutting out either
9077: 7740:. The cobordism groups defined above are, from this point of view, the homology groups of a point: 6972: 4623: 3727: 1577:
and "cobordism with G-structure", respectively. Under favourable technical conditions these form a
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When there is additional structure, the notion of cobordism must be formulated more precisely: a
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Kosinski, Antoni A. (October 19, 2007). "Differential Manifolds" (Document). Dover Publications.
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A cobordism between a single circle (at the top) and a pair of disjoint circles (at the bottom).
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is a (compact) closed manifold that is not the boundary of a manifold, as is explained below.
9140: 9067: 8947: 8775: 8709: 7008: 5347: 5169: 4414: 1450: 879: 326: 8741: 8131:{\displaystyle {\begin{cases}\Omega _{n}^{G}(X)\to H_{n}(X)\\(M,f)\mapsto f_{*}\end{cases}}} 9288: 9240: 9214: 9062: 8605: 8496: 8464: 6549: 5623: 4596: 3778:) is defined by gluing the right end of the first to the left end of the second, yielding ( 3641: 3340: 1729: 629: 540: 120: 48: 6735:: both ends have opposite orientations. It is also the correct definition in the sense of 6092: 3636:
The Morse/Smale theorem states that for a Morse function on a cobordism, the flowlines of
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are very different, reflecting the difference between oriented and unoriented cobordism.
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As per the above definition, a surgery on the circle consists of cutting out a copy of
1703: 1506: 721: 701: 681: 661: 452: 432: 213: 209: 8314:{\displaystyle \Omega _{n}^{G}(X)=\sum _{p+q=n}H_{p}(X;\Omega _{q}^{G}({\text{pt}})).} 4025: 1048: 9328: 9321: 9187: 9145: 9010: 8964: 8914: 8811: 8783: 8748: 8665: 8624: 8591: 8365: 8329: 6366: 5269: 1714: 1692: 1617: 272: 9353: 8736: 6548:, the orthogonal group, giving back the unoriented cobordism, but also the subgroup 3665: 9101: 9047: 8956: 8843:
American Mathematical Society Translations, Ser. 2, Vol. 11, pp. 1–114 (1959).
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In 1959, C.T.C. Wall proved that two manifolds are cobordant if and only if their
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is to calculate the cobordism classes of manifolds subject to various conditions.
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is allowed to have a neighborhood that is homeomorphic to an open subset of the
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Unlike in the unoriented cobordism group, where every element is two-torsion, 2
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if such a cobordism exists. All manifolds cobordant to a fixed given manifold
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for clarity) are such that the boundary (with the induced orientations) is
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is not in general an oriented boundary, that is, 2 ≠ 0 when considered in
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are manifolds with boundary, then the boundary of the product manifold is
108: 9255: 8884: 8797: 8694: 8441: 8374:. Note that even for similar groups, Thom spectra can be very different: 6537: 6308: 2719:
The pictures in Fig. 1 show that the result of doing this is either (i)
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The pair of pants is an example of a more general cobordism: for any two
1083:(see the figure at right). Thus the pair of pants is a cobordism between 225: 40: 8827:
Methods of algebraic topology from the point of view of cobordism theory
8385:
From the point of view of spectra, unoriented cobordism is a product of
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into an abelian group. The identity element of this group is the class
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is an unoriented cobordism invariant. This is implied by the equation
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with the reversed orientation. For example, boundary of the cylinder
2586:{\displaystyle \mathbb {D} ^{p+1}\times \mathbb {S} ^{q-1}\subset N.} 1873: 739: 574: 8960: 8661: 8201:, in which case the bordism groups are the ordinary homology groups 8198: 8148:
apart from the dimension axiom. This does not mean that the groups
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is Morse and such that all critical points occur in the interior of
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Every cobordism is a union of elementary cobordisms, by the work of
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On the formal group laws of unoriented and complex cobordism theory
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the polynomial algebra generated by the oriented cobordism classes
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The previous example is a particular case, since the connected sum
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are fundamental in the study of high-dimensional manifolds, namely
92: 55: 8913:(ed.). World Scientific Publishing Co. Pte. Ltd., Hackensack, NJ. 7535: 2981: 2787: 2779: 8556:
While every cobordism is a cospan, the category of cobordisms is
3835: 3567:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{2}\subset M,} 2620: 1718: 7517:{\displaystyle \sigma :\Omega _{4i}^{\text{SO}}\to \mathbb {Z} } 5157:{\displaystyle w_{i}(M)\in H^{i}\left(M;\mathbb {F} _{2}\right)} 1809:, which are harder to compute than the differentiable variants. 953:
to be compact in the definition of cobordism. Note however that
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construction. Cobordism theory became part of the apparatus of
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Geometry, and the connection with Morse theory and handlebodies
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Topological library. Part 1: cobordisms and their applications
4229:. The cartesian product of manifolds defines a multiplication 1541:, meaning boundary. Hence bordism is the study of boundaries. 1223:{\displaystyle \mathbb {S} ^{1}\mathbin {\#} \mathbb {S} ^{1}} 8772:
The classifying spaces for surgery and cobordism of manifolds
4226: 3458: 3127: 7794:{\displaystyle \Omega _{n}^{G}=\Omega _{n}^{G}({\text{pt}})} 6051:{\displaystyle \chi :{\mathfrak {N}}_{2i}\to \mathbb {Z} /2} 3350: 658:-dimensional compact differentiable manifold with boundary, 235:. In algebraic topology, cobordism theories are fundamental 115:(i.e., differentiable), but there are now also versions for 19: 9002: 8743:
A history of algebraic and differential topology, 1900–1960
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is a well-defined group homomorphism. For example, for any
5825:{\displaystyle \chi :{\mathfrak {N}}_{i}\to \mathbb {Z} /2} 3695:
showed that cobordism groups could be computed by means of
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in geometric work on manifolds. It came to prominence when
2203:{\displaystyle \mathbb {D} ^{p+1}\times \mathbb {S} ^{q-1}} 8841:
Smooth manifolds and their applications in homotopy theory
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The bordism and cobordism theories of a space satisfy the
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The oriented cobordism groups are given modulo torsion by
3506:{\displaystyle N=\mathbb {S} ^{1}\times \mathbb {S} ^{1},} 3311:
is called a Morse function on a cobordism. The cobordism (
1569:, or carry some other additional structure referred to as 8955:(2). The Annals of Mathematics, Vol. 72, No. 2: 292–311. 8932:
Quelques propriétés globales des variétés différentiables
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in the oriented case), defining a natural transformation
7014:
The low-dimensional oriented cobordism groups are :
4583:{\displaystyle {\mathfrak {N}}_{*}=\mathbb {F} _{2}\left} 3323:) is a union of the traces of a sequence of surgeries on 3255:) that can be identified with the trace of this surgery. 72:) of a manifold. Two manifolds of the same dimension are 7258:
is defined as the signature of the intersection form on
6961:{\displaystyle y_{4i}=\left\in \Omega _{4i}^{\text{SO}}} 5232:{\displaystyle \in H_{n}\left(M;\mathbb {F} _{2}\right)} 3626:{\displaystyle \mathbb {D} ^{1}\times \mathbb {D} ^{2}.} 3118:{\displaystyle \mathbb {S} ^{1}\times \mathbb {D} ^{1}.} 3071:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{2},} 2879:{\displaystyle \mathbb {S} ^{1}\times \mathbb {D} ^{1}.} 2712:{\displaystyle \mathbb {D} ^{1}\times \mathbb {S} ^{0}.} 1802:{\displaystyle \Omega _{*}^{PL}(X),\Omega _{*}^{TOP}(X)} 8861:
Complex cobordism and stable homotopy groups of spheres
8621:
Complex cobordism and stable homotopy groups of spheres
6536:) is some group homomorphism. This is referred to as a 3852:
List of cohomology theories § Unoriented cobordism
3199: + 1)-dimensional manifold, and suppose that 3166:{\displaystyle \mathbb {S} ^{1}\times \mathbb {S} ^{1}} 3024:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{2}} 2970:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{2}} 2926:{\displaystyle \mathbb {S} ^{1}\times \mathbb {D} ^{1}} 2832:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{2}} 2665:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{1}} 2147:{\displaystyle \mathbb {S} ^{p}\times \mathbb {D} ^{q}} 1363:{\displaystyle \mathbb {S} ^{0}\times \mathbb {D} ^{n}} 58:
of the same dimension, set up using the concept of the
4421:, which depend on the stable isomorphism class of the 8853:
Bull. Amer. Math. Soc., 75 (1969) pp. 1293–1298.
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List of cohomology theories § Oriented cobordism
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Null-cobordisms with additional structure are called
1458: 1376: 1332: 1301: 1268: 1236: 1190: 1154: 1120: 949: Ă— [0, 1); for this reason we require 882: 820: 782: 747: 724: 704: 684: 664: 632: 582: 543: 506: 475: 455: 435: 337: 291: 156: 8704: 7007:
is determined by the Stiefel–Whitney and Pontrjagin
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The low-dimensional unoriented cobordism groups are
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Proc. Camb. Phil. Soc. 57, pp. 200–208 (1961).
8141:which is far from being an isomorphism in general. 5879:{\displaystyle i_{1},\cdots ,i_{k}\in \mathbb {N} } 3734:played a basic role in the Atiyah–Segal axioms for 3684:for the relationship between bordism and homology. 3664:Cobordism had its roots in the (failed) attempt by 804:{\displaystyle j\colon N\hookrightarrow \partial W} 769:{\displaystyle i\colon M\hookrightarrow \partial W} 8740: 8517: 8313: 8199:reduces to a product of ordinary homology theories 8181: 8130: 8008: 7986: 7834: 7793: 7724: 7675: 7630: 7589: 7516: 7464: 7329: 7297: 7235: 6999: 6960: 6864: 6773: 6727: 6676: 6607: 6493: 6349: 6287: 6171: 6107: 6081: 6050: 5991: 5878: 5824: 5768: 5745: 5654: 5608: 5334: 5260: 5231: 5156: 5076: 4884: 4832: 4777: 4721: 4651: 4612: 4582: 4470: 4397: 4344: 4277: 4217: 4188: 4157: 4094: 4052:-manifolds which are boundaries. Further we have 4040: 4014: 3983: 3915: 3883: 3856:The set of cobordism classes of closed unoriented 3625: 3566: 3505: 3449: 3411: 3165: 3117: 3070: 3023: 2985:Fig. 2c. This shape cannot be embedded in 3-space. 2969: 2925: 2878: 2831: 2769: 2740: 2711: 2664: 2585: 2493: 2356: 2202: 2146: 2095: 1926: 1801: 1644: 1608: 1487: 1393: 1362: 1318: 1287: 1254: 1222: 1176: 1137: 906: 865: 803: 768: 730: 710: 690: 670: 650: 618: 561: 521: 484: 461: 441: 418: 309: 177: 6501:. Considering only manifolds and cobordisms with 6172:{\displaystyle \chi (M\times N)=\chi (M)\chi (N)} 1401:, and the cobordism is the trace of the surgery. 217: 9403: 8909:. Series on Knots and Everything. Vol. 39. 6299:Cobordism of manifolds with additional structure 4778:{\displaystyle \left(i_{1},\cdots ,i_{k}\right)} 8945:(1960). "Determination of the cobordism ring". 8889:On Thom spectra, orientability, and (co)bordism 7536:Cobordism as an extraordinary cohomology theory 3991:; this is a well-defined operation which turns 3830:from a category of cobordisms to a category of 3682:Cobordism as an extraordinary cohomology theory 1488:{\displaystyle \mathbb {P} ^{2n}(\mathbb {R} )} 1099:is given by the disjoint union of three disks. 961:required to be connected; as a consequence, if 8866: 9018: 8766: 8586:, Classics in Mathematics, Berlin, New York: 7552:. Similarly, every cobordism theory Ω has an 4158:{\displaystyle M\sqcup M=\partial (M\times )} 3860:-dimensional manifolds is usually denoted by 1437:-sphere is null-cobordant since it bounds a ( 2443: 2437: 1534: 945:is the boundary of the non-compact manifold 866:{\displaystyle \partial W=i(M)\sqcup j(N)~.} 410: 338: 84:of a compact manifold one dimension higher. 6975:(Thom, 1952). The oriented cobordism group 4359:, with the grading given by the dimension. 1425:and the empty manifold; in other words, if 999:The simplest example of a cobordism is the 9386: 9359: 9025: 9011: 6494:{\displaystyle {\tilde {\nu }}:M\to X_{k}} 4833:{\displaystyle i\geqslant 1,i\neq 2^{j}-1} 4593:the polynomial algebra with one generator 876:The terminology is usually abbreviated to 8735: 8350:, the Thom spectrum is composed from the 8002: 7972: 7510: 7444: 7420: 7402: 7378: 7298:{\displaystyle H^{2i}(M)\in \mathbb {Z} } 7291: 7216: 7181: 7051: 6925: 6908: 6820: 6812: 6401:). Given a collection of spaces and maps 6331: 6209: 6072: 6036: 5971: 5947: 5929: 5905: 5872: 5810: 5648: 5590: 5549: 5533: 5461: 5389: 5320: 5306: 5248: 5214: 5139: 5064: 4722:{\displaystyle =\in {\mathfrak {N}}_{n},} 4511: 4471:{\displaystyle =0\in {\mathfrak {N}}_{n}} 4429:has a stably trivial tangent bundle then 4205: 3673: 3610: 3595: 3545: 3530: 3490: 3475: 3437: 3399: 3384: 3369: 3173:but if they are different, we obtain the 3153: 3138: 3102: 3087: 3055: 3040: 3011: 2996: 2957: 2942: 2913: 2898: 2863: 2848: 2819: 2804: 2757: 2728: 2696: 2681: 2652: 2637: 2558: 2537: 2476: 2455: 2424: 2409: 2330: 2309: 2280: 2265: 2245: 2230: 2184: 2163: 2134: 2119: 2072: 2051: 2024: 2009: 1905: 1890: 1522:, and the study of cobordisms as objects 1478: 1461: 1350: 1335: 1239: 1210: 1193: 381: 294: 8904: 8800:(1962). "A survey of cobordism theory". 8761: 8699:Stable homotopy and generalised homology 8584:Algebraic topology—homotopy and homology 7691:, and the generalized cohomology groups 6774:{\displaystyle \Omega _{*}^{\text{SO}}.} 6576:, and the trivial group, giving rise to 5655:{\displaystyle \chi (M)\in \mathbb {Z} } 3349: 2980: 2786: 2778: 2619: 1047: 240: 216:. In geometric topology, cobordisms are 142:whose boundary is the disjoint union of 18: 8618: 8581: 7000:{\displaystyle \Omega _{*}^{\text{SO}}} 5756:for any compact manifold with boundary 4398:{\displaystyle \in {\mathfrak {N}}_{n}} 3845: 3299:. By general position, one can assume 1812: 1574: 9404: 8796: 8339:Cobordism theories are represented by 4892:the Stiefel-Whitney numbers are equal 3916:{\displaystyle \Omega _{n}^{\text{O}}} 3745: 1709:In a similar vein, a standard tool in 9006: 8646:"Determination of the Cobordism Ring" 8534: 6618: 6365:, which in turn is a subspace of the 6319:into a sufficiently high-dimensional 4885:{\displaystyle i_{1}+\cdots +i_{k}=n} 4413:is determined by the Stiefel–Whitney 3687:Bordism was explicitly introduced by 522:{\displaystyle \partial M=\emptyset } 8941: 8643: 8568:form a partition of the boundary of 7597:and cohomology ("cobordism") groups 1732:. This gives rise to bordism groups 1295:is obtained from the disjoint union 178:{\displaystyle \partial W=M\sqcup N} 8195:Atiyah–Hirzebruch spectral sequence 7556:, with homology ("bordism") groups 7544:theory (real, complex etc.) has an 6453:-structure is a lift of Îœ to a map 6199: 6018: 5795: 5662:modulo 2 of an unoriented manifold 5571: 5514: 5483: 5442: 5411: 5370: 4729:if and only if for each collection 4705: 4495: 4457: 4384: 4331: 4298: 4189:{\displaystyle {\mathfrak {N}}_{n}} 4175: 4015:{\displaystyle {\mathfrak {N}}_{n}} 4001: 3884:{\displaystyle {\mathfrak {N}}_{n}} 3870: 3207: + 1, then the level-set 1076:together make up the boundary of a 321:is similar, except that a point of 13: 8280: 8212: 8182:{\displaystyle \Omega _{G}^{n}(X)} 8156: 8035: 7835:{\displaystyle \Omega _{n}^{G}(X)} 7809: 7766: 7748: 7725:{\displaystyle \Omega _{G}^{*}(X)} 7699: 7676:{\displaystyle \Omega _{*}^{G}(X)} 7650: 7642:. The generalized homology groups 7631:{\displaystyle \Omega _{G}^{n}(X)} 7605: 7590:{\displaystyle \Omega _{n}^{G}(X)} 7564: 7489: 7193: 7159: 7127: 7095: 7063: 7029: 6983: 6941: 6794: 6754: 6591: 6433:) (compatible with the inclusions 6350:{\displaystyle \mathbb {R} ^{n+k}} 6082:{\displaystyle i\in \mathbb {N} ,} 5681: 4125: 4086: 4032: 3899: 3450:{\displaystyle M=\mathbb {S} ^{2}} 3182: 2299: 2220: 2110:, via cutting out the interior of 1979: 1976: 1970: 1967: 1964: 1770: 1740: 1628: 1592: 1273: 1204: 1177:{\displaystyle M\mathbin {\#} M'.} 1159: 821: 795: 760: 516: 507: 476: 245:topological quantum field theories 157: 14: 9433: 8984: 8936:Commentarii Mathematici Helvetici 8829:, Izv. Akad. Nauk SSSR Ser. Mat. 8708:; Voitsekhovskii, M. I. (2001) , 3891:(rather than the more systematic 3715:, and in the first proofs of the 3327:, one for each critical point of 3275:) there exists a smooth function 3219: + Î”) is obtained from 1687:= SO for oriented cobordism, and 1288:{\displaystyle M\mathbin {\#} M'} 1255:{\displaystyle \mathbb {S} ^{1}.} 310:{\displaystyle \mathbb {R} ^{n}.} 237:extraordinary cohomology theories 9385: 9358: 9348: 9338: 9327: 9317: 9316: 9110: 8419: 8412:is rather more complicated than 5261:{\displaystyle \mathbb {F} _{2}} 4218:{\displaystyle \mathbb {F} _{2}} 3824:topological quantum field theory 3738:, which is an important part of 3736:topological quantum field theory 3730:and cobordisms between these as 2770:{\displaystyle \mathbb {S} ^{1}} 2741:{\displaystyle \mathbb {S} ^{1}} 1652:are the coefficient groups of a 1429:is the entire boundary of some ( 1421:if there is a cobordism between 204:in dimensions ≄ 4 – because the 8901:, Princeton Univ. Press (1968). 7898:if there exists a G-cobordism ( 7554:extraordinary cohomology theory 7546:extraordinary cohomology theory 6737:extraordinary cohomology theory 6608:{\displaystyle \Omega _{*}^{G}} 3713:Hirzebruch–Riemann–Roch theorem 3705:extraordinary cohomology theory 1645:{\displaystyle \Omega _{*}^{G}} 1609:{\displaystyle \Omega _{*}^{G}} 811:with disjoint images such that 8905:Taimanov, Iskander A. (2007). 8637: 8612: 8575: 8550: 8528: 8512: 8500: 8487: 8305: 8302: 8294: 8270: 8232: 8226: 8176: 8170: 8118: 8112: 8099: 8096: 8084: 8077: 8071: 8058: 8055: 8049: 7987:{\displaystyle \mathbb {Z} /2} 7829: 7823: 7788: 7780: 7719: 7713: 7670: 7664: 7625: 7619: 7584: 7578: 7506: 7448: 7440: 7406: 7398: 7321: 7315: 7284: 7278: 6929: 6921: 6722: 6713: 6671: 6662: 6478: 6466: 6273: 6267: 6253: 6247: 6241: 6238: 6232: 6225: 6219: 6204: 6166: 6160: 6154: 6148: 6139: 6127: 6032: 5975: 5967: 5933: 5925: 5806: 5713: 5703: 5641: 5635: 5324: 5316: 5185: 5179: 5110: 5104: 5051: 5045: 5039: 5033: 5010: 5004: 4971: 4965: 4959: 4953: 4930: 4924: 4696: 4690: 4684: 4678: 4537: 4442: 4436: 4375: 4369: 4269: 4257: 4251: 4245: 4242: 4236: 4152: 4149: 4137: 4128: 4089: 4083: 4077: 4071: 4065: 4059: 4035: 4029: 3978: 3966: 3960: 3954: 3948: 3942: 3672:purely in terms of manifolds ( 2399: 2387: 2002: 1989: 1954: 1796: 1790: 1763: 1757: 1683:= O for unoriented cobordism, 1482: 1474: 1404: 1326:by surgery on an embedding of 1091:. A simpler cobordism between 901: 883: 854: 848: 839: 833: 792: 757: 645: 633: 613: 583: 556: 544: 373: 341: 1: 8701:, Univ. Chicago Press (1974). 8688: 5342:, the cobordism class of the 4659:. Thus two unoriented closed 4652:{\displaystyle i\neq 2^{j}-1} 3078:we glue back in the cylinder 2748:again, or (ii) two copies of 2615: 532: 250: 9032: 8770:; Milgram, R. James (1979). 8619:Ravenel, D.C. (April 1986). 8009:{\displaystyle \mathbb {Z} } 7528:≄ 1, and an isomorphism for 7339:Hirzebruch signature theorem 6728:{\displaystyle M\sqcup (-M)} 6677:{\displaystyle M\sqcup (-N)} 6089:and a group isomorphism for 3799:). A cobordism is a kind of 3354:The 3-dimensional cobordism 3235:-surgery. The inverse image 1702:. Many more are detailed by 255: 91: + 1)-dimensional 7: 8874:Encyclopedia of Mathematics 8803:L'Enseignement MathĂ©matique 8715:Encyclopedia of Mathematics 8582:Switzer, Robert M. (2002), 8455:List of cohomology theories 8435: 7330:{\displaystyle \sigma (M).} 5335:{\displaystyle x_{i}=\left} 3717:Atiyah–Singer index theorem 3343:for each critical point of 3031:: Having cut out two disks 1817:Recall that in general, if 1654:generalised homology theory 1560: 994: 619:{\displaystyle (W;M,N,i,j)} 500:manifold without boundary ( 10: 9438: 9279:Banach fixed-point theorem 8780:Princeton University Press 8544:Princeton University Press 8334:homotopy groups of spheres 8328:, oriented cobordism and 7951:fundamental homology class 6622: 3849: 3726:with compact manifolds as 3659: 1545:means "jointly bound", so 1445:. On the other hand, the 2 1394:{\displaystyle M\sqcup M'} 1319:{\displaystyle M\sqcup M'} 1138:{\displaystyle M\sqcup M'} 485:{\displaystyle \partial M} 9312: 9269: 9233: 9119: 9108: 9040: 8899:Notes on cobordism theory 8737:DieudonnĂ©, Jean Alexandre 8540:Notes on cobordism theory 8387:Eilenberg–MacLane spectra 8146:Eilenberg–Steenrod axioms 6973:complex projective spaces 6357:gives rise to a map from 5279:it is possible to choose 4048:consisting of all closed 1679:. The basic examples are 8867:Yuli B. Rudyak (2001) , 8480: 7964:) (with coefficients in 3935:respectively, we define 3586:by attaching a 1-handle 3243:() defines a cobordism ( 278:(i.e., near each point) 241:categories of cobordisms 8644:Wall, C. T. C. (1960). 8572:is a global constraint. 8362:standard vector bundles 7866:(with G-structure) and 6645:) (also referred to as 4663:-dimensional manifolds 4405:of a closed unoriented 4227:field with two elements 4196:is a vector space over 3817:dagger compact category 1620:. The cobordism groups 1524:cobordisms of manifolds 1106:-dimensional manifolds 907:{\displaystyle (W;M,N)} 206:word problem for groups 102:-dimensional manifold ∂ 9334:Mathematics portal 9234:Metrics and properties 9220:Second-countable space 8999:on the Manifold Atlas. 8993:on the Manifold Atlas. 8747:. Boston: BirkhĂ€user. 8519: 8315: 8183: 8132: 8010: 7988: 7945:-dimensional manifold 7862:-dimensional manifold 7836: 7795: 7726: 7677: 7632: 7591: 7518: 7466: 7331: 7299: 7254:-dimensional manifold 7237: 7009:characteristic numbers 7001: 6962: 6866: 6775: 6729: 6678: 6609: 6495: 6351: 6289: 6173: 6109: 6083: 6052: 5993: 5880: 5826: 5770: 5747: 5656: 5610: 5336: 5262: 5233: 5158: 5078: 4886: 4834: 4779: 4723: 4653: 4614: 4584: 4472: 4415:characteristic numbers 4409:-dimensional manifold 4399: 4346: 4279: 4219: 4190: 4159: 4096: 4042: 4016: 3985: 3917: 3885: 3633: 3627: 3568: 3507: 3451: 3413: 3167: 3119: 3072: 3025: 2986: 2971: 2927: 2880: 2833: 2792: 2784: 2771: 2742: 2713: 2666: 2625: 2587: 2495: 2358: 2204: 2148: 2097: 1928: 1856:Now, given a manifold 1803: 1646: 1610: 1535: 1489: 1395: 1364: 1320: 1289: 1256: 1224: 1178: 1139: 1114:â€Č, the disjoint union 1053: 1037:) is a cobordism from 941:Every closed manifold 908: 867: 805: 770: 732: 712: 692: 672: 652: 620: 563: 523: 486: 463: 443: 420: 319:manifold with boundary 311: 179: 138:is a compact manifold 36: 16:Concept in mathematics 9412:Differential topology 8948:Annals of Mathematics 8863:, Acad. Press (1986). 8776:Princeton, New Jersey 8730:Bordism and cobordism 8650:Annals of Mathematics 8520: 8518:{\displaystyle (n+1)} 8316: 8184: 8133: 8011: 7989: 7922:, which restricts to 7837: 7796: 7727: 7678: 7633: 7592: 7519: 7467: 7344:For example, for any 7332: 7300: 7238: 7002: 6963: 6867: 6776: 6730: 6679: 6623:Further information: 6610: 6496: 6352: 6315:Îœ of an immersion of 6311:). Very briefly, the 6290: 6174: 6117:Moreover, because of 6110: 6084: 6053: 5994: 5881: 5827: 5771: 5748: 5657: 5611: 5348:real projective space 5337: 5263: 5234: 5170:Stiefel-Whitney class 5159: 5079: 4887: 4835: 4780: 4724: 4654: 4615: 4613:{\displaystyle x_{i}} 4585: 4473: 4400: 4347: 4280: 4220: 4191: 4160: 4097: 4043: 4017: 3986: 3918: 3886: 3850:Further information: 3815:. The category is a 3628: 3569: 3508: 3452: 3414: 3353: 3231: âˆ’ Î”) by a 3168: 3120: 3073: 3026: 2984: 2972: 2928: 2881: 2834: 2790: 2782: 2772: 2743: 2714: 2667: 2623: 2595:reversing the surgery 2588: 2496: 2359: 2210:along their boundary 2205: 2149: 2098: 1929: 1804: 1730:topological manifolds 1726:piecewise linear (PL) 1647: 1611: 1573:. This gives rise to 1490: 1451:real projective space 1396: 1365: 1321: 1290: 1257: 1225: 1179: 1140: 1051: 909: 868: 806: 771: 733: 713: 693: 673: 653: 651:{\displaystyle (n+1)} 621: 564: 562:{\displaystyle (n+1)} 524: 496:is, by definition, a 487: 464: 444: 421: 312: 282:to an open subset of 260:Roughly speaking, an 180: 121:topological manifolds 22: 9289:Invariance of domain 9241:Euler characteristic 9215:Bundle (mathematics) 8497: 8465:Cobordism hypothesis 8208: 8152: 8023: 7998: 7968: 7805: 7744: 7695: 7646: 7601: 7560: 7479: 7365: 7309: 7262: 7021: 6979: 6882: 6790: 6750: 6704: 6653: 6587: 6457: 6326: 6186: 6121: 6108:{\displaystyle i=1.} 6093: 6062: 6006: 5892: 5836: 5783: 5760: 5673: 5629: 5624:Euler characteristic 5360: 5283: 5243: 5176: 5091: 4899: 4844: 4793: 4789:-tuples of integers 4733: 4675: 4624: 4597: 4489: 4433: 4366: 4362:The cobordism class 4292: 4233: 4200: 4169: 4110: 4056: 4026: 3995: 3939: 3895: 3864: 3846:Unoriented cobordism 3590: 3525: 3464: 3426: 3358: 3339:× by attaching one 3133: 3082: 3035: 2991: 2937: 2893: 2843: 2799: 2752: 2723: 2676: 2632: 2532: 2378: 2217: 2158: 2114: 1945: 1879: 1813:Surgery construction 1736: 1624: 1588: 1575:"oriented cobordism" 1520:bordism of manifolds 1456: 1374: 1330: 1299: 1266: 1234: 1188: 1152: 1145:is cobordant to the 1118: 880: 818: 780: 745: 722: 702: 682: 662: 630: 580: 541: 504: 473: 453: 433: 335: 289: 218:intimately connected 154: 87:The boundary of an ( 49:equivalence relation 9299:Tychonoff's theorem 9294:PoincarĂ© conjecture 9048:General (point-set) 8475:Timeline of bordism 8293: 8225: 8169: 8048: 7994:in general, and in 7878:a map. Such pairs ( 7822: 7779: 7761: 7712: 7663: 7618: 7577: 7505: 7206: 7172: 7140: 7108: 7076: 7042: 6996: 6957: 6807: 6767: 6647:oriented cobordisms 6604: 6540:. Examples include 3912: 3834:. That is, it is a 3746:Categorical aspects 3642:handle presentation 3263:Given a cobordism ( 1789: 1756: 1641: 1605: 243:are the domains of 9417:Algebraic topology 9284:De Rham cohomology 9205:Polyhedral complex 9195:Simplicial complex 8891:, Springer (2008). 8623:. Academic Press. 8515: 8460:Symplectic filling 8426:Pontrjagin numbers 8366:classifying spaces 8311: 8279: 8259: 8211: 8179: 8155: 8128: 8123: 8034: 8006: 7984: 7846:classes of pairs ( 7832: 7808: 7791: 7765: 7747: 7722: 7698: 7673: 7649: 7628: 7604: 7587: 7563: 7514: 7488: 7475:The signature map 7462: 7327: 7305:and is denoted by 7295: 7233: 7231: 7192: 7158: 7126: 7094: 7062: 7028: 6997: 6982: 6958: 6940: 6862: 6793: 6771: 6753: 6725: 6674: 6619:Oriented cobordism 6605: 6590: 6558:oriented cobordism 6491: 6347: 6285: 6280: 6169: 6105: 6079: 6048: 5989: 5876: 5822: 5766: 5743: 5652: 5606: 5604: 5332: 5258: 5229: 5154: 5074: 4882: 4830: 4775: 4719: 4649: 4620:in each dimension 4610: 4580: 4468: 4395: 4342: 4327: 4278:{\displaystyle =,} 4275: 4215: 4186: 4155: 4095:{\displaystyle +=} 4092: 4038: 4012: 3984:{\displaystyle +=} 3981: 3913: 3898: 3881: 3668:in 1895 to define 3634: 3623: 3564: 3503: 3447: 3409: 3307:. In this setting 3163: 3115: 3068: 3021: 2987: 2967: 2923: 2876: 2829: 2793: 2785: 2767: 2738: 2709: 2662: 2626: 2583: 2491: 2354: 2200: 2144: 2093: 1924: 1799: 1769: 1739: 1642: 1627: 1606: 1591: 1533:comes from French 1485: 1391: 1360: 1316: 1285: 1262:The connected sum 1252: 1220: 1174: 1135: 1054: 904: 863: 801: 766: 728: 708: 688: 668: 648: 616: 559: 519: 482: 459: 449:; the boundary of 439: 416: 307: 214:algebraic topology 210:geometric topology 175: 130:between manifolds 47:is a fundamental 37: 9399: 9398: 9188:fundamental group 8951:. Second Series. 8938:28, 17-86 (1954). 8920:978-981-270-559-4 8789:978-0-691-08226-4 8754:978-0-8176-3388-2 8726:Michael F. Atiyah 8706:Anosov, Dmitri V. 8597:978-3-540-42750-6 8542:. Princeton, NJ: 8330:complex cobordism 8300: 8238: 7786: 7503: 7204: 7170: 7138: 7106: 7074: 7040: 6994: 6955: 6805: 6765: 6556:, giving rise to 6469: 6367:classifying space 5769:{\displaystyle W} 5270:fundamental class 4312: 3910: 3722:In the 1980s the 3640:â€Č give rise to a 3335:is obtained from 2524:is obtained from 1975: 1700:complex manifolds 1693:complex cobordism 1618:cartesian product 1557:, hence the co-. 1555:cohomology theory 1230:is isomorphic to 859: 731:{\displaystyle N} 711:{\displaystyle M} 691:{\displaystyle n} 671:{\displaystyle W} 626:consisting of an 462:{\displaystyle M} 442:{\displaystyle M} 273:topological space 9429: 9389: 9388: 9362: 9361: 9352: 9342: 9332: 9331: 9320: 9319: 9114: 9027: 9020: 9013: 9004: 9003: 8980: 8924: 8881: 8833:(1967), 855–951. 8819: 8793: 8763: 8758: 8746: 8722: 8695:John Frank Adams 8682: 8681: 8641: 8635: 8634: 8616: 8610: 8608: 8579: 8573: 8554: 8548: 8547: 8536:Stong, Robert E. 8532: 8526: 8524: 8522: 8521: 8516: 8491: 8450:Link concordance 8400: 8346:: given a group 8326:framed cobordism 8320: 8318: 8317: 8312: 8301: 8298: 8292: 8287: 8269: 8268: 8258: 8224: 8219: 8188: 8186: 8185: 8180: 8168: 8163: 8137: 8135: 8134: 8129: 8127: 8126: 8111: 8110: 8070: 8069: 8047: 8042: 8015: 8013: 8012: 8007: 8005: 7993: 7991: 7990: 7985: 7980: 7975: 7842:is the group of 7841: 7839: 7838: 7833: 7821: 7816: 7800: 7798: 7797: 7792: 7787: 7784: 7778: 7773: 7760: 7755: 7731: 7729: 7728: 7723: 7711: 7706: 7682: 7680: 7679: 7674: 7662: 7657: 7637: 7635: 7634: 7629: 7617: 7612: 7596: 7594: 7593: 7588: 7576: 7571: 7524:is onto for all 7523: 7521: 7520: 7515: 7513: 7504: 7501: 7499: 7471: 7469: 7468: 7463: 7455: 7451: 7447: 7439: 7438: 7437: 7436: 7423: 7405: 7397: 7396: 7395: 7394: 7381: 7336: 7334: 7333: 7328: 7304: 7302: 7301: 7296: 7294: 7277: 7276: 7250:of an oriented 4 7242: 7240: 7239: 7234: 7232: 7225: 7224: 7219: 7205: 7202: 7200: 7184: 7171: 7168: 7166: 7139: 7136: 7134: 7107: 7104: 7102: 7075: 7072: 7070: 7054: 7041: 7038: 7036: 7006: 7004: 7003: 6998: 6995: 6992: 6990: 6967: 6965: 6964: 6959: 6956: 6953: 6951: 6936: 6932: 6928: 6920: 6919: 6911: 6897: 6896: 6871: 6869: 6868: 6863: 6858: 6854: 6841: 6840: 6823: 6815: 6806: 6803: 6801: 6780: 6778: 6777: 6772: 6766: 6763: 6761: 6734: 6732: 6731: 6726: 6683: 6681: 6680: 6675: 6633:and cobordisms ( 6614: 6612: 6611: 6606: 6603: 6598: 6578:framed cobordism 6512:may be given by 6500: 6498: 6497: 6492: 6490: 6489: 6471: 6470: 6462: 6371:orthogonal group 6356: 6354: 6353: 6348: 6346: 6345: 6334: 6294: 6292: 6291: 6286: 6284: 6283: 6277: 6276: 6218: 6217: 6212: 6203: 6202: 6178: 6176: 6175: 6170: 6114: 6112: 6111: 6106: 6088: 6086: 6085: 6080: 6075: 6058:is onto for all 6057: 6055: 6054: 6049: 6044: 6039: 6031: 6030: 6022: 6021: 5998: 5996: 5995: 5990: 5982: 5978: 5974: 5966: 5965: 5964: 5963: 5950: 5932: 5924: 5923: 5922: 5921: 5908: 5885: 5883: 5882: 5877: 5875: 5867: 5866: 5848: 5847: 5831: 5829: 5828: 5823: 5818: 5813: 5805: 5804: 5799: 5798: 5775: 5773: 5772: 5767: 5752: 5750: 5749: 5744: 5742: 5741: 5732: 5728: 5727: 5726: 5688: 5687: 5661: 5659: 5658: 5653: 5651: 5615: 5613: 5612: 5607: 5605: 5598: 5593: 5581: 5580: 5575: 5574: 5557: 5552: 5541: 5536: 5524: 5523: 5518: 5517: 5493: 5492: 5487: 5486: 5469: 5464: 5452: 5451: 5446: 5445: 5421: 5420: 5415: 5414: 5397: 5392: 5380: 5379: 5374: 5373: 5341: 5339: 5338: 5333: 5331: 5327: 5323: 5315: 5314: 5309: 5295: 5294: 5267: 5265: 5264: 5259: 5257: 5256: 5251: 5238: 5236: 5235: 5230: 5228: 5224: 5223: 5222: 5217: 5200: 5199: 5163: 5161: 5160: 5155: 5153: 5149: 5148: 5147: 5142: 5125: 5124: 5103: 5102: 5083: 5081: 5080: 5075: 5073: 5072: 5067: 5058: 5054: 5032: 5031: 5030: 5029: 5003: 5002: 5001: 5000: 4978: 4974: 4952: 4951: 4950: 4949: 4923: 4922: 4921: 4920: 4891: 4889: 4888: 4883: 4875: 4874: 4856: 4855: 4839: 4837: 4836: 4831: 4823: 4822: 4784: 4782: 4781: 4776: 4774: 4770: 4769: 4768: 4750: 4749: 4728: 4726: 4725: 4720: 4715: 4714: 4709: 4708: 4658: 4656: 4655: 4650: 4642: 4641: 4619: 4617: 4616: 4611: 4609: 4608: 4589: 4587: 4586: 4581: 4579: 4575: 4568: 4567: 4540: 4535: 4534: 4520: 4519: 4514: 4505: 4504: 4499: 4498: 4477: 4475: 4474: 4469: 4467: 4466: 4461: 4460: 4404: 4402: 4401: 4396: 4394: 4393: 4388: 4387: 4351: 4349: 4348: 4343: 4341: 4340: 4335: 4334: 4326: 4308: 4307: 4302: 4301: 4284: 4282: 4281: 4276: 4224: 4222: 4221: 4216: 4214: 4213: 4208: 4195: 4193: 4192: 4187: 4185: 4184: 4179: 4178: 4164: 4162: 4161: 4156: 4101: 4099: 4098: 4093: 4047: 4045: 4044: 4041:{\displaystyle } 4039: 4021: 4019: 4018: 4013: 4011: 4010: 4005: 4004: 3990: 3988: 3987: 3982: 3922: 3920: 3919: 3914: 3911: 3908: 3906: 3890: 3888: 3887: 3882: 3880: 3879: 3874: 3873: 3828:monoidal functor 3740:quantum topology 3632: 3630: 3629: 3624: 3619: 3618: 3613: 3604: 3603: 3598: 3573: 3571: 3570: 3565: 3554: 3553: 3548: 3539: 3538: 3533: 3512: 3510: 3509: 3504: 3499: 3498: 3493: 3484: 3483: 3478: 3456: 3454: 3453: 3448: 3446: 3445: 3440: 3418: 3416: 3415: 3410: 3408: 3407: 3402: 3393: 3392: 3387: 3378: 3377: 3372: 3172: 3170: 3169: 3164: 3162: 3161: 3156: 3147: 3146: 3141: 3124: 3122: 3121: 3116: 3111: 3110: 3105: 3096: 3095: 3090: 3077: 3075: 3074: 3069: 3064: 3063: 3058: 3049: 3048: 3043: 3030: 3028: 3027: 3022: 3020: 3019: 3014: 3005: 3004: 2999: 2976: 2974: 2973: 2968: 2966: 2965: 2960: 2951: 2950: 2945: 2932: 2930: 2929: 2924: 2922: 2921: 2916: 2907: 2906: 2901: 2885: 2883: 2882: 2877: 2872: 2871: 2866: 2857: 2856: 2851: 2838: 2836: 2835: 2830: 2828: 2827: 2822: 2813: 2812: 2807: 2776: 2774: 2773: 2768: 2766: 2765: 2760: 2747: 2745: 2744: 2739: 2737: 2736: 2731: 2718: 2716: 2715: 2710: 2705: 2704: 2699: 2690: 2689: 2684: 2671: 2669: 2668: 2663: 2661: 2660: 2655: 2646: 2645: 2640: 2592: 2590: 2589: 2584: 2573: 2572: 2561: 2552: 2551: 2540: 2500: 2498: 2497: 2492: 2490: 2486: 2485: 2484: 2479: 2470: 2469: 2458: 2447: 2446: 2433: 2432: 2427: 2418: 2417: 2412: 2363: 2361: 2360: 2355: 2350: 2346: 2345: 2344: 2333: 2324: 2323: 2312: 2295: 2294: 2283: 2274: 2273: 2268: 2259: 2255: 2254: 2253: 2248: 2239: 2238: 2233: 2209: 2207: 2206: 2201: 2199: 2198: 2187: 2178: 2177: 2166: 2153: 2151: 2150: 2145: 2143: 2142: 2137: 2128: 2127: 2122: 2102: 2100: 2099: 2094: 2092: 2088: 2087: 2086: 2075: 2066: 2065: 2054: 2043: 2042: 2041: 2040: 2039: 2038: 2027: 2018: 2017: 2012: 2005: 1982: 1973: 1933: 1931: 1930: 1925: 1914: 1913: 1908: 1899: 1898: 1893: 1852: 1808: 1806: 1805: 1800: 1788: 1777: 1755: 1747: 1651: 1649: 1648: 1643: 1640: 1635: 1615: 1613: 1612: 1607: 1604: 1599: 1540: 1494: 1492: 1491: 1486: 1481: 1473: 1472: 1464: 1400: 1398: 1397: 1392: 1390: 1369: 1367: 1366: 1361: 1359: 1358: 1353: 1344: 1343: 1338: 1325: 1323: 1322: 1317: 1315: 1294: 1292: 1291: 1286: 1284: 1276: 1261: 1259: 1258: 1253: 1248: 1247: 1242: 1229: 1227: 1226: 1221: 1219: 1218: 1213: 1207: 1202: 1201: 1196: 1183: 1181: 1180: 1175: 1170: 1162: 1144: 1142: 1141: 1136: 1134: 1068:of two circles, 1036: 1029: 1022: 1008: 913: 911: 910: 905: 872: 870: 869: 864: 857: 810: 808: 807: 802: 775: 773: 772: 767: 737: 735: 734: 729: 717: 715: 714: 709: 697: 695: 694: 689: 677: 675: 674: 669: 657: 655: 654: 649: 625: 623: 622: 617: 568: 566: 565: 560: 528: 526: 525: 520: 491: 489: 488: 483: 468: 466: 465: 460: 448: 446: 445: 440: 425: 423: 422: 417: 403: 402: 390: 389: 384: 372: 371: 353: 352: 316: 314: 313: 308: 303: 302: 297: 184: 182: 181: 176: 117:piecewise linear 113:smooth manifolds 51:on the class of 9437: 9436: 9432: 9431: 9430: 9428: 9427: 9426: 9402: 9401: 9400: 9395: 9326: 9308: 9304:Urysohn's lemma 9265: 9229: 9115: 9106: 9078:low-dimensional 9036: 9031: 8987: 8961:10.2307/1970136 8921: 8895:Robert E. Stong 8857:Douglas Ravenel 8790: 8755: 8691: 8686: 8685: 8662:10.2307/1970136 8642: 8638: 8631: 8617: 8613: 8598: 8588:Springer-Verlag 8580: 8576: 8555: 8551: 8533: 8529: 8498: 8495: 8494: 8492: 8488: 8483: 8438: 8430:Stiefel numbers 8422: 8403: 8398: 8372: 8358: 8297: 8288: 8283: 8264: 8260: 8242: 8220: 8215: 8209: 8206: 8205: 8164: 8159: 8153: 8150: 8149: 8122: 8121: 8106: 8102: 8081: 8080: 8065: 8061: 8043: 8038: 8027: 8026: 8024: 8021: 8020: 8001: 7999: 7996: 7995: 7976: 7971: 7969: 7966: 7965: 7958: 7817: 7812: 7806: 7803: 7802: 7783: 7774: 7769: 7756: 7751: 7745: 7742: 7741: 7707: 7702: 7696: 7693: 7692: 7658: 7653: 7647: 7644: 7643: 7613: 7608: 7602: 7599: 7598: 7572: 7567: 7561: 7558: 7557: 7538: 7509: 7500: 7492: 7480: 7477: 7476: 7443: 7432: 7428: 7424: 7419: 7418: 7401: 7390: 7386: 7382: 7377: 7376: 7375: 7371: 7366: 7363: 7362: 7356: 7350: 7310: 7307: 7306: 7290: 7269: 7265: 7263: 7260: 7259: 7230: 7229: 7220: 7215: 7214: 7207: 7201: 7196: 7189: 7188: 7180: 7173: 7167: 7162: 7155: 7154: 7141: 7135: 7130: 7123: 7122: 7109: 7103: 7098: 7091: 7090: 7077: 7071: 7066: 7059: 7058: 7050: 7043: 7037: 7032: 7024: 7022: 7019: 7018: 6991: 6986: 6980: 6977: 6976: 6952: 6944: 6924: 6912: 6907: 6906: 6905: 6901: 6889: 6885: 6883: 6880: 6879: 6833: 6829: 6828: 6824: 6819: 6811: 6802: 6797: 6791: 6788: 6787: 6762: 6757: 6751: 6748: 6747: 6705: 6702: 6701: 6654: 6651: 6650: 6627: 6621: 6599: 6594: 6588: 6585: 6584: 6510: 6485: 6481: 6461: 6460: 6458: 6455: 6454: 6423: 6417: 6413: 6406: 6335: 6330: 6329: 6327: 6324: 6323: 6321:Euclidean space 6307:-structure (or 6301: 6279: 6278: 6260: 6256: 6229: 6228: 6213: 6208: 6207: 6198: 6197: 6190: 6189: 6187: 6184: 6183: 6122: 6119: 6118: 6094: 6091: 6090: 6071: 6063: 6060: 6059: 6040: 6035: 6023: 6017: 6016: 6015: 6007: 6004: 6003: 5970: 5959: 5955: 5951: 5946: 5945: 5928: 5917: 5913: 5909: 5904: 5903: 5902: 5898: 5893: 5890: 5889: 5871: 5862: 5858: 5843: 5839: 5837: 5834: 5833: 5814: 5809: 5800: 5794: 5793: 5792: 5784: 5781: 5780: 5761: 5758: 5757: 5737: 5733: 5716: 5712: 5696: 5692: 5680: 5676: 5674: 5671: 5670: 5647: 5630: 5627: 5626: 5603: 5602: 5594: 5589: 5582: 5576: 5570: 5569: 5568: 5565: 5564: 5553: 5548: 5537: 5532: 5525: 5519: 5513: 5512: 5511: 5508: 5507: 5494: 5488: 5482: 5481: 5480: 5477: 5476: 5465: 5460: 5453: 5447: 5441: 5440: 5439: 5436: 5435: 5422: 5416: 5410: 5409: 5408: 5405: 5404: 5393: 5388: 5381: 5375: 5369: 5368: 5367: 5363: 5361: 5358: 5357: 5319: 5310: 5305: 5304: 5303: 5299: 5290: 5286: 5284: 5281: 5280: 5252: 5247: 5246: 5244: 5241: 5240: 5218: 5213: 5212: 5205: 5201: 5195: 5191: 5177: 5174: 5173: 5143: 5138: 5137: 5130: 5126: 5120: 5116: 5098: 5094: 5092: 5089: 5088: 5068: 5063: 5062: 5025: 5021: 5020: 5016: 4996: 4992: 4991: 4987: 4986: 4982: 4945: 4941: 4940: 4936: 4916: 4912: 4911: 4907: 4906: 4902: 4900: 4897: 4896: 4870: 4866: 4851: 4847: 4845: 4842: 4841: 4818: 4814: 4794: 4791: 4790: 4764: 4760: 4745: 4741: 4740: 4736: 4734: 4731: 4730: 4710: 4704: 4703: 4702: 4676: 4673: 4672: 4671:are cobordant, 4637: 4633: 4625: 4622: 4621: 4604: 4600: 4598: 4595: 4594: 4563: 4559: 4536: 4530: 4526: 4525: 4521: 4515: 4510: 4509: 4500: 4494: 4493: 4492: 4490: 4487: 4486: 4462: 4456: 4455: 4454: 4434: 4431: 4430: 4389: 4383: 4382: 4381: 4367: 4364: 4363: 4336: 4330: 4329: 4328: 4316: 4303: 4297: 4296: 4295: 4293: 4290: 4289: 4234: 4231: 4230: 4209: 4204: 4203: 4201: 4198: 4197: 4180: 4174: 4173: 4172: 4170: 4167: 4166: 4111: 4108: 4107: 4057: 4054: 4053: 4027: 4024: 4023: 4006: 4000: 3999: 3998: 3996: 3993: 3992: 3940: 3937: 3936: 3907: 3902: 3896: 3893: 3892: 3875: 3869: 3868: 3867: 3865: 3862: 3861: 3854: 3848: 3787: 3748: 3697:homotopy theory 3662: 3644:of the triple ( 3614: 3609: 3608: 3599: 3594: 3593: 3591: 3588: 3587: 3549: 3544: 3543: 3534: 3529: 3528: 3526: 3523: 3522: 3494: 3489: 3488: 3479: 3474: 3473: 3465: 3462: 3461: 3441: 3436: 3435: 3427: 3424: 3423: 3403: 3398: 3397: 3388: 3383: 3382: 3373: 3368: 3367: 3359: 3356: 3355: 3331:. The manifold 3261: 3185: 3183:Morse functions 3180: 3157: 3152: 3151: 3142: 3137: 3136: 3134: 3131: 3130: 3106: 3101: 3100: 3091: 3086: 3085: 3083: 3080: 3079: 3059: 3054: 3053: 3044: 3039: 3038: 3036: 3033: 3032: 3015: 3010: 3009: 3000: 2995: 2994: 2992: 2989: 2988: 2961: 2956: 2955: 2946: 2941: 2940: 2938: 2935: 2934: 2917: 2912: 2911: 2902: 2897: 2896: 2894: 2891: 2890: 2867: 2862: 2861: 2852: 2847: 2846: 2844: 2841: 2840: 2823: 2818: 2817: 2808: 2803: 2802: 2800: 2797: 2796: 2761: 2756: 2755: 2753: 2750: 2749: 2732: 2727: 2726: 2724: 2721: 2720: 2700: 2695: 2694: 2685: 2680: 2679: 2677: 2674: 2673: 2656: 2651: 2650: 2641: 2636: 2635: 2633: 2630: 2629: 2618: 2593:This is called 2562: 2557: 2556: 2541: 2536: 2535: 2533: 2530: 2529: 2480: 2475: 2474: 2459: 2454: 2453: 2452: 2448: 2428: 2423: 2422: 2413: 2408: 2407: 2406: 2402: 2379: 2376: 2375: 2371:of the surgery 2334: 2329: 2328: 2313: 2308: 2307: 2306: 2302: 2284: 2279: 2278: 2269: 2264: 2263: 2249: 2244: 2243: 2234: 2229: 2228: 2227: 2223: 2218: 2215: 2214: 2188: 2183: 2182: 2167: 2162: 2161: 2159: 2156: 2155: 2138: 2133: 2132: 2123: 2118: 2117: 2115: 2112: 2111: 2076: 2071: 2070: 2055: 2050: 2049: 2048: 2044: 2028: 2023: 2022: 2013: 2008: 2007: 2006: 2001: 2000: 1996: 1992: 1963: 1946: 1943: 1942: 1909: 1904: 1903: 1894: 1889: 1888: 1880: 1877: 1876: 1826: 1815: 1778: 1773: 1748: 1743: 1737: 1734: 1733: 1704:Robert E. Stong 1667:restricts to a 1636: 1631: 1625: 1622: 1621: 1600: 1595: 1589: 1586: 1585: 1563: 1500:bordism problem 1477: 1465: 1460: 1459: 1457: 1454: 1453: 1407: 1383: 1375: 1372: 1371: 1354: 1349: 1348: 1339: 1334: 1333: 1331: 1328: 1327: 1308: 1300: 1297: 1296: 1277: 1272: 1267: 1264: 1263: 1243: 1238: 1237: 1235: 1232: 1231: 1214: 1209: 1208: 1203: 1197: 1192: 1191: 1189: 1186: 1185: 1163: 1158: 1153: 1150: 1149: 1127: 1119: 1116: 1115: 1031: 1024: 1014: 1003: 997: 991:are cobordant. 982: 971: 932:cobordism class 881: 878: 877: 819: 816: 815: 781: 778: 777: 746: 743: 742: 723: 720: 719: 703: 700: 699: 683: 680: 679: 663: 660: 659: 631: 628: 627: 581: 578: 577: 542: 539: 538: 535: 505: 502: 501: 494:closed manifold 474: 471: 470: 454: 451: 450: 434: 431: 430: 398: 394: 385: 380: 379: 367: 363: 348: 344: 336: 333: 332: 298: 293: 292: 290: 287: 286: 284:Euclidean space 258: 253: 155: 152: 151: 17: 12: 11: 5: 9435: 9425: 9424: 9422:Surgery theory 9419: 9414: 9397: 9396: 9394: 9393: 9383: 9382: 9381: 9376: 9371: 9356: 9346: 9336: 9324: 9313: 9310: 9309: 9307: 9306: 9301: 9296: 9291: 9286: 9281: 9275: 9273: 9267: 9266: 9264: 9263: 9258: 9253: 9251:Winding number 9248: 9243: 9237: 9235: 9231: 9230: 9228: 9227: 9222: 9217: 9212: 9207: 9202: 9197: 9192: 9191: 9190: 9185: 9183:homotopy group 9175: 9174: 9173: 9168: 9163: 9158: 9153: 9143: 9138: 9133: 9123: 9121: 9117: 9116: 9109: 9107: 9105: 9104: 9099: 9094: 9093: 9092: 9082: 9081: 9080: 9070: 9065: 9060: 9055: 9050: 9044: 9042: 9038: 9037: 9030: 9029: 9022: 9015: 9007: 9001: 9000: 8994: 8986: 8985:External links 8983: 8982: 8981: 8943:Wall, C. T. C. 8939: 8925: 8919: 8902: 8892: 8885:Yuli B. Rudyak 8882: 8864: 8854: 8847:Daniel Quillen 8844: 8837:Lev Pontryagin 8834: 8823:Sergei Novikov 8820: 8794: 8788: 8764: 8759: 8753: 8733: 8723: 8702: 8690: 8687: 8684: 8683: 8656:(2): 292–311. 8636: 8629: 8611: 8596: 8574: 8549: 8527: 8514: 8511: 8508: 8505: 8502: 8493:The notation " 8485: 8484: 8482: 8479: 8478: 8477: 8472: 8470:Cobordism ring 8467: 8462: 8457: 8452: 8447: 8437: 8434: 8432:are the same. 8421: 8418: 8401: 8370: 8356: 8322: 8321: 8310: 8307: 8304: 8296: 8291: 8286: 8282: 8278: 8275: 8272: 8267: 8263: 8257: 8254: 8251: 8248: 8245: 8241: 8237: 8234: 8231: 8228: 8223: 8218: 8214: 8178: 8175: 8172: 8167: 8162: 8158: 8139: 8138: 8125: 8120: 8117: 8114: 8109: 8105: 8101: 8098: 8095: 8092: 8089: 8086: 8083: 8082: 8079: 8076: 8073: 8068: 8064: 8060: 8057: 8054: 8051: 8046: 8041: 8037: 8033: 8032: 8030: 8004: 7983: 7979: 7974: 7956: 7831: 7828: 7825: 7820: 7815: 7811: 7790: 7782: 7777: 7772: 7768: 7764: 7759: 7754: 7750: 7721: 7718: 7715: 7710: 7705: 7701: 7672: 7669: 7666: 7661: 7656: 7652: 7638:for any space 7627: 7624: 7621: 7616: 7611: 7607: 7586: 7583: 7580: 7575: 7570: 7566: 7537: 7534: 7512: 7508: 7498: 7495: 7491: 7487: 7484: 7473: 7472: 7461: 7458: 7454: 7450: 7446: 7442: 7435: 7431: 7427: 7422: 7417: 7414: 7411: 7408: 7404: 7400: 7393: 7389: 7385: 7380: 7374: 7370: 7354: 7348: 7326: 7323: 7320: 7317: 7314: 7293: 7289: 7286: 7283: 7280: 7275: 7272: 7268: 7244: 7243: 7228: 7223: 7218: 7213: 7210: 7208: 7199: 7195: 7191: 7190: 7187: 7183: 7179: 7176: 7174: 7165: 7161: 7157: 7156: 7153: 7150: 7147: 7144: 7142: 7133: 7129: 7125: 7124: 7121: 7118: 7115: 7112: 7110: 7101: 7097: 7093: 7092: 7089: 7086: 7083: 7080: 7078: 7069: 7065: 7061: 7060: 7057: 7053: 7049: 7046: 7044: 7035: 7031: 7027: 7026: 6989: 6985: 6969: 6968: 6950: 6947: 6943: 6939: 6935: 6931: 6927: 6923: 6918: 6915: 6910: 6904: 6900: 6895: 6892: 6888: 6873: 6872: 6861: 6857: 6853: 6850: 6847: 6844: 6839: 6836: 6832: 6827: 6822: 6818: 6814: 6810: 6800: 6796: 6770: 6760: 6756: 6724: 6721: 6718: 6715: 6712: 6709: 6673: 6670: 6667: 6664: 6661: 6658: 6620: 6617: 6602: 6597: 6593: 6566:unitary group 6508: 6488: 6484: 6480: 6477: 6474: 6468: 6465: 6421: 6415: 6411: 6404: 6344: 6341: 6338: 6333: 6300: 6297: 6296: 6295: 6282: 6275: 6272: 6269: 6266: 6263: 6259: 6255: 6252: 6249: 6246: 6243: 6240: 6237: 6234: 6231: 6230: 6227: 6224: 6221: 6216: 6211: 6206: 6201: 6196: 6195: 6193: 6168: 6165: 6162: 6159: 6156: 6153: 6150: 6147: 6144: 6141: 6138: 6135: 6132: 6129: 6126: 6104: 6101: 6098: 6078: 6074: 6070: 6067: 6047: 6043: 6038: 6034: 6029: 6026: 6020: 6014: 6011: 6000: 5999: 5988: 5985: 5981: 5977: 5973: 5969: 5962: 5958: 5954: 5949: 5944: 5941: 5938: 5935: 5931: 5927: 5920: 5916: 5912: 5907: 5901: 5897: 5874: 5870: 5865: 5861: 5857: 5854: 5851: 5846: 5842: 5821: 5817: 5812: 5808: 5803: 5797: 5791: 5788: 5765: 5754: 5753: 5740: 5736: 5731: 5725: 5722: 5719: 5715: 5711: 5708: 5705: 5702: 5699: 5695: 5691: 5686: 5683: 5679: 5650: 5646: 5643: 5640: 5637: 5634: 5617: 5616: 5601: 5597: 5592: 5588: 5585: 5583: 5579: 5573: 5567: 5566: 5563: 5560: 5556: 5551: 5547: 5544: 5540: 5535: 5531: 5528: 5526: 5522: 5516: 5510: 5509: 5506: 5503: 5500: 5497: 5495: 5491: 5485: 5479: 5478: 5475: 5472: 5468: 5463: 5459: 5456: 5454: 5450: 5444: 5438: 5437: 5434: 5431: 5428: 5425: 5423: 5419: 5413: 5407: 5406: 5403: 5400: 5396: 5391: 5387: 5384: 5382: 5378: 5372: 5366: 5365: 5330: 5326: 5322: 5318: 5313: 5308: 5302: 5298: 5293: 5289: 5255: 5250: 5227: 5221: 5216: 5211: 5208: 5204: 5198: 5194: 5190: 5187: 5184: 5181: 5152: 5146: 5141: 5136: 5133: 5129: 5123: 5119: 5115: 5112: 5109: 5106: 5101: 5097: 5085: 5084: 5071: 5066: 5061: 5057: 5053: 5050: 5047: 5044: 5041: 5038: 5035: 5028: 5024: 5019: 5015: 5012: 5009: 5006: 4999: 4995: 4990: 4985: 4981: 4977: 4973: 4970: 4967: 4964: 4961: 4958: 4955: 4948: 4944: 4939: 4935: 4932: 4929: 4926: 4919: 4915: 4910: 4905: 4881: 4878: 4873: 4869: 4865: 4862: 4859: 4854: 4850: 4829: 4826: 4821: 4817: 4813: 4810: 4807: 4804: 4801: 4798: 4773: 4767: 4763: 4759: 4756: 4753: 4748: 4744: 4739: 4718: 4713: 4707: 4701: 4698: 4695: 4692: 4689: 4686: 4683: 4680: 4648: 4645: 4640: 4636: 4632: 4629: 4607: 4603: 4591: 4590: 4578: 4574: 4571: 4566: 4562: 4558: 4555: 4552: 4549: 4546: 4543: 4539: 4533: 4529: 4524: 4518: 4513: 4508: 4503: 4497: 4465: 4459: 4453: 4450: 4447: 4444: 4441: 4438: 4423:tangent bundle 4392: 4386: 4380: 4377: 4374: 4371: 4357:graded algebra 4353: 4352: 4339: 4333: 4325: 4322: 4319: 4315: 4311: 4306: 4300: 4274: 4271: 4268: 4265: 4262: 4259: 4256: 4253: 4250: 4247: 4244: 4241: 4238: 4212: 4207: 4183: 4177: 4154: 4151: 4148: 4145: 4142: 4139: 4136: 4133: 4130: 4127: 4124: 4121: 4118: 4115: 4091: 4088: 4085: 4082: 4079: 4076: 4073: 4070: 4067: 4064: 4061: 4037: 4034: 4031: 4009: 4003: 3980: 3977: 3974: 3971: 3968: 3965: 3962: 3959: 3956: 3953: 3950: 3947: 3944: 3905: 3901: 3878: 3872: 3847: 3844: 3783: 3747: 3744: 3689:Lev Pontryagin 3674:DieudonnĂ© 1989 3666:Henri PoincarĂ© 3661: 3658: 3622: 3617: 3612: 3607: 3602: 3597: 3578:obtained from 3563: 3560: 3557: 3552: 3547: 3542: 3537: 3532: 3521:by surgery on 3517:obtained from 3502: 3497: 3492: 3487: 3482: 3477: 3472: 3469: 3444: 3439: 3434: 3431: 3419:between the 2- 3406: 3401: 3396: 3391: 3386: 3381: 3376: 3371: 3366: 3363: 3260: 3257: 3193:Morse function 3184: 3181: 3179: 3178: 3160: 3155: 3150: 3145: 3140: 3114: 3109: 3104: 3099: 3094: 3089: 3067: 3062: 3057: 3052: 3047: 3042: 3018: 3013: 3008: 3003: 2998: 2978: 2964: 2959: 2954: 2949: 2944: 2920: 2915: 2910: 2905: 2900: 2887: 2875: 2870: 2865: 2860: 2855: 2850: 2826: 2821: 2816: 2811: 2806: 2764: 2759: 2735: 2730: 2708: 2703: 2698: 2693: 2688: 2683: 2672:and gluing in 2659: 2654: 2649: 2644: 2639: 2617: 2614: 2582: 2579: 2576: 2571: 2568: 2565: 2560: 2555: 2550: 2547: 2544: 2539: 2528:by surgery on 2502: 2501: 2489: 2483: 2478: 2473: 2468: 2465: 2462: 2457: 2451: 2445: 2442: 2439: 2436: 2431: 2426: 2421: 2416: 2411: 2405: 2401: 2398: 2395: 2392: 2389: 2386: 2383: 2365: 2364: 2353: 2349: 2343: 2340: 2337: 2332: 2327: 2322: 2319: 2316: 2311: 2305: 2301: 2298: 2293: 2290: 2287: 2282: 2277: 2272: 2267: 2262: 2258: 2252: 2247: 2242: 2237: 2232: 2226: 2222: 2197: 2194: 2191: 2186: 2181: 2176: 2173: 2170: 2165: 2154:and gluing in 2141: 2136: 2131: 2126: 2121: 2104: 2103: 2091: 2085: 2082: 2079: 2074: 2069: 2064: 2061: 2058: 2053: 2047: 2037: 2034: 2031: 2026: 2021: 2016: 2011: 2004: 1999: 1995: 1991: 1988: 1985: 1981: 1978: 1972: 1969: 1966: 1962: 1959: 1956: 1953: 1950: 1923: 1920: 1917: 1912: 1907: 1902: 1897: 1892: 1887: 1884: 1814: 1811: 1798: 1795: 1792: 1787: 1784: 1781: 1776: 1772: 1768: 1765: 1762: 1759: 1754: 1751: 1746: 1742: 1713:is surgery on 1711:surgery theory 1671:-structure on 1663:-structure on 1639: 1634: 1630: 1603: 1598: 1594: 1583:cobordism ring 1562: 1559: 1484: 1480: 1476: 1471: 1468: 1463: 1419:null-cobordant 1406: 1403: 1389: 1386: 1382: 1379: 1357: 1352: 1347: 1342: 1337: 1314: 1311: 1307: 1304: 1283: 1280: 1275: 1271: 1251: 1246: 1241: 1217: 1212: 1206: 1200: 1195: 1173: 1169: 1166: 1161: 1157: 1133: 1130: 1126: 1123: 1060:consists of a 996: 993: 980: 976: = âˆ‚ 969: 965: = âˆ‚ 903: 900: 897: 894: 891: 888: 885: 874: 873: 862: 856: 853: 850: 847: 844: 841: 838: 835: 832: 829: 826: 823: 800: 797: 794: 791: 788: 785: 765: 762: 759: 756: 753: 750: 727: 707: 687: 667: 647: 644: 641: 638: 635: 615: 612: 609: 606: 603: 600: 597: 594: 591: 588: 585: 558: 555: 552: 549: 546: 534: 531: 518: 515: 512: 509: 492:. Finally, a 481: 478: 469:is denoted by 458: 438: 427: 426: 415: 412: 409: 406: 401: 397: 393: 388: 383: 378: 375: 370: 366: 362: 359: 356: 351: 347: 343: 340: 306: 301: 296: 257: 254: 252: 249: 233:surgery theory 198:diffeomorphism 190:diffeomorphism 174: 171: 168: 165: 162: 159: 78:disjoint union 15: 9: 6: 4: 3: 2: 9434: 9423: 9420: 9418: 9415: 9413: 9410: 9409: 9407: 9392: 9384: 9380: 9377: 9375: 9372: 9370: 9367: 9366: 9365: 9357: 9355: 9351: 9347: 9345: 9341: 9337: 9335: 9330: 9325: 9323: 9315: 9314: 9311: 9305: 9302: 9300: 9297: 9295: 9292: 9290: 9287: 9285: 9282: 9280: 9277: 9276: 9274: 9272: 9268: 9262: 9261:Orientability 9259: 9257: 9254: 9252: 9249: 9247: 9244: 9242: 9239: 9238: 9236: 9232: 9226: 9223: 9221: 9218: 9216: 9213: 9211: 9208: 9206: 9203: 9201: 9198: 9196: 9193: 9189: 9186: 9184: 9181: 9180: 9179: 9176: 9172: 9169: 9167: 9164: 9162: 9159: 9157: 9154: 9152: 9149: 9148: 9147: 9144: 9142: 9139: 9137: 9134: 9132: 9128: 9125: 9124: 9122: 9118: 9113: 9103: 9100: 9098: 9097:Set-theoretic 9095: 9091: 9088: 9087: 9086: 9083: 9079: 9076: 9075: 9074: 9071: 9069: 9066: 9064: 9061: 9059: 9058:Combinatorial 9056: 9054: 9051: 9049: 9046: 9045: 9043: 9039: 9035: 9028: 9023: 9021: 9016: 9014: 9009: 9008: 9005: 8998: 8995: 8992: 8989: 8988: 8978: 8974: 8970: 8966: 8962: 8958: 8954: 8950: 8949: 8944: 8940: 8937: 8933: 8929: 8926: 8922: 8916: 8912: 8908: 8903: 8900: 8896: 8893: 8890: 8886: 8883: 8880: 8876: 8875: 8870: 8865: 8862: 8858: 8855: 8852: 8848: 8845: 8842: 8838: 8835: 8832: 8828: 8824: 8821: 8817: 8813: 8809: 8805: 8804: 8799: 8795: 8791: 8785: 8781: 8777: 8773: 8769: 8765: 8760: 8756: 8750: 8745: 8744: 8738: 8734: 8731: 8727: 8724: 8721: 8717: 8716: 8711: 8707: 8703: 8700: 8696: 8693: 8692: 8679: 8675: 8671: 8667: 8663: 8659: 8655: 8651: 8647: 8640: 8632: 8630:0-12-583430-6 8626: 8622: 8615: 8607: 8603: 8599: 8593: 8589: 8585: 8578: 8571: 8567: 8563: 8559: 8553: 8545: 8541: 8537: 8531: 8509: 8506: 8503: 8490: 8486: 8476: 8473: 8471: 8468: 8466: 8463: 8461: 8458: 8456: 8453: 8451: 8448: 8446: 8444: 8440: 8439: 8433: 8431: 8427: 8420:Other results 8417: 8415: 8411: 8407: 8396: 8392: 8388: 8383: 8381: 8377: 8373: 8367: 8363: 8359: 8353: 8349: 8345: 8342: 8337: 8335: 8331: 8327: 8308: 8289: 8284: 8276: 8273: 8265: 8261: 8255: 8252: 8249: 8246: 8243: 8239: 8235: 8229: 8221: 8216: 8204: 8203: 8202: 8200: 8196: 8193:, though the 8192: 8173: 8165: 8160: 8147: 8142: 8115: 8107: 8103: 8093: 8090: 8087: 8074: 8066: 8062: 8052: 8044: 8039: 8028: 8019: 8018: 8017: 7981: 7977: 7963: 7959: 7952: 7948: 7944: 7939: 7937: 7933: 7929: 7925: 7921: 7917: 7913: 7910:) with a map 7909: 7905: 7901: 7897: 7893: 7889: 7885: 7881: 7877: 7873: 7869: 7865: 7861: 7857: 7853: 7849: 7845: 7826: 7818: 7813: 7775: 7770: 7762: 7757: 7752: 7739: 7735: 7734:contravariant 7716: 7708: 7703: 7690: 7686: 7667: 7659: 7654: 7641: 7622: 7614: 7609: 7581: 7573: 7568: 7555: 7551: 7547: 7543: 7542:vector bundle 7533: 7531: 7527: 7496: 7493: 7485: 7482: 7459: 7456: 7452: 7433: 7429: 7425: 7415: 7412: 7409: 7391: 7387: 7383: 7372: 7368: 7361: 7360: 7359: 7357: 7347: 7342: 7340: 7324: 7318: 7312: 7287: 7281: 7273: 7270: 7266: 7257: 7253: 7249: 7226: 7221: 7211: 7209: 7197: 7185: 7177: 7175: 7163: 7151: 7148: 7145: 7143: 7131: 7119: 7116: 7113: 7111: 7099: 7087: 7084: 7081: 7079: 7067: 7055: 7047: 7045: 7033: 7017: 7016: 7015: 7012: 7010: 6987: 6974: 6948: 6945: 6937: 6933: 6916: 6913: 6902: 6898: 6893: 6890: 6886: 6878: 6877: 6876: 6859: 6855: 6851: 6848: 6845: 6842: 6837: 6834: 6830: 6825: 6816: 6808: 6798: 6786: 6785: 6784: 6781: 6768: 6758: 6745: 6740: 6738: 6719: 6716: 6710: 6707: 6699: 6696: Ă—  6695: 6691: 6687: 6668: 6665: 6659: 6656: 6648: 6644: 6640: 6636: 6632: 6626: 6616: 6600: 6595: 6581: 6579: 6575: 6573: 6569: 6563: 6559: 6555: 6553: 6547: 6543: 6539: 6535: 6531: 6527: 6523: 6519: 6515: 6511: 6504: 6486: 6482: 6475: 6472: 6463: 6452: 6448: 6444: 6440: 6436: 6432: 6428: 6424: 6414: 6407: 6400: 6396: 6392: 6389: +  6388: 6384: 6380: 6376: 6372: 6368: 6364: 6360: 6342: 6339: 6336: 6322: 6318: 6314: 6313:normal bundle 6310: 6306: 6270: 6264: 6261: 6257: 6250: 6244: 6235: 6222: 6214: 6191: 6182: 6181: 6180: 6163: 6157: 6151: 6145: 6142: 6136: 6133: 6130: 6124: 6115: 6102: 6099: 6096: 6076: 6068: 6065: 6045: 6041: 6027: 6024: 6012: 6009: 5986: 5983: 5979: 5960: 5956: 5952: 5942: 5939: 5936: 5918: 5914: 5910: 5899: 5895: 5888: 5887: 5886: 5868: 5863: 5859: 5855: 5852: 5849: 5844: 5840: 5819: 5815: 5801: 5789: 5786: 5777: 5763: 5738: 5734: 5729: 5723: 5720: 5717: 5709: 5706: 5700: 5697: 5693: 5689: 5684: 5677: 5669: 5668: 5667: 5665: 5644: 5638: 5632: 5625: 5620: 5599: 5595: 5586: 5584: 5577: 5561: 5558: 5554: 5545: 5542: 5538: 5529: 5527: 5520: 5504: 5501: 5498: 5496: 5489: 5473: 5470: 5466: 5457: 5455: 5448: 5432: 5429: 5426: 5424: 5417: 5401: 5398: 5394: 5385: 5383: 5376: 5356: 5355: 5354: 5351: 5349: 5346:-dimensional 5345: 5328: 5311: 5300: 5296: 5291: 5287: 5278: 5273: 5271: 5268:-coefficient 5253: 5225: 5219: 5209: 5206: 5202: 5196: 5192: 5188: 5182: 5171: 5167: 5150: 5144: 5134: 5131: 5127: 5121: 5117: 5113: 5107: 5099: 5095: 5069: 5059: 5055: 5048: 5042: 5036: 5026: 5022: 5017: 5013: 5007: 4997: 4993: 4988: 4983: 4979: 4975: 4968: 4962: 4956: 4946: 4942: 4937: 4933: 4927: 4917: 4913: 4908: 4903: 4895: 4894: 4893: 4879: 4876: 4871: 4867: 4863: 4860: 4857: 4852: 4848: 4827: 4824: 4819: 4815: 4811: 4808: 4805: 4802: 4799: 4796: 4788: 4771: 4765: 4761: 4757: 4754: 4751: 4746: 4742: 4737: 4716: 4711: 4699: 4693: 4687: 4681: 4670: 4666: 4662: 4646: 4643: 4638: 4634: 4630: 4627: 4605: 4601: 4576: 4572: 4569: 4564: 4560: 4556: 4553: 4550: 4547: 4544: 4541: 4531: 4527: 4522: 4516: 4506: 4501: 4485: 4484: 4483: 4481: 4463: 4451: 4448: 4445: 4439: 4428: 4424: 4420: 4416: 4412: 4408: 4390: 4378: 4372: 4360: 4358: 4337: 4323: 4320: 4317: 4313: 4309: 4304: 4288: 4287: 4286: 4272: 4266: 4263: 4260: 4254: 4248: 4239: 4228: 4210: 4181: 4165:. Therefore, 4146: 4143: 4140: 4134: 4131: 4122: 4119: 4116: 4113: 4105: 4080: 4074: 4068: 4062: 4051: 4007: 3975: 3972: 3969: 3963: 3957: 3951: 3945: 3934: 3930: 3926: 3925:abelian group 3903: 3876: 3859: 3853: 3843: 3839: 3837: 3833: 3832:vector spaces 3829: 3825: 3820: 3818: 3814: 3810: 3806: 3802: 3798: 3794: 3790: 3786: 3781: 3777: 3773: 3769: 3765: 3761: 3757: 3753: 3743: 3741: 3737: 3733: 3729: 3725: 3720: 3718: 3714: 3710: 3706: 3702: 3698: 3694: 3690: 3685: 3683: 3679: 3675: 3671: 3667: 3657: 3655: 3651: 3647: 3643: 3639: 3620: 3615: 3605: 3600: 3585: 3581: 3577: 3561: 3558: 3555: 3550: 3540: 3535: 3520: 3516: 3500: 3495: 3485: 3480: 3470: 3467: 3460: 3442: 3432: 3429: 3422: 3404: 3394: 3389: 3379: 3374: 3364: 3361: 3352: 3348: 3346: 3342: 3338: 3334: 3330: 3326: 3322: 3318: 3314: 3310: 3306: 3302: 3298: 3294: 3290: 3286: 3283:→ such that 3282: 3278: 3274: 3270: 3266: 3256: 3254: 3250: 3246: 3242: 3238: 3234: 3230: 3226: 3222: 3218: 3214: 3210: 3206: 3202: 3198: 3194: 3190: 3187:Suppose that 3176: 3158: 3148: 3143: 3129: 3112: 3107: 3097: 3092: 3065: 3060: 3050: 3045: 3016: 3006: 3001: 2983: 2979: 2962: 2952: 2947: 2918: 2908: 2903: 2889: 2888: 2886: 2873: 2868: 2858: 2853: 2824: 2814: 2809: 2789: 2781: 2777: 2762: 2733: 2706: 2701: 2691: 2686: 2657: 2647: 2642: 2622: 2613: 2611: 2607: 2603: 2602:Marston Morse 2598: 2596: 2580: 2577: 2574: 2569: 2566: 2563: 2553: 2548: 2545: 2542: 2527: 2523: 2520:). Note that 2519: 2515: 2511: 2507: 2487: 2481: 2471: 2466: 2463: 2460: 2449: 2440: 2434: 2429: 2419: 2414: 2403: 2396: 2393: 2390: 2384: 2381: 2374: 2373: 2372: 2370: 2351: 2347: 2341: 2338: 2335: 2325: 2320: 2317: 2314: 2303: 2296: 2291: 2288: 2285: 2275: 2270: 2260: 2256: 2250: 2240: 2235: 2224: 2213: 2212: 2211: 2195: 2192: 2189: 2179: 2174: 2171: 2168: 2139: 2129: 2124: 2109: 2089: 2083: 2080: 2077: 2067: 2062: 2059: 2056: 2045: 2035: 2032: 2029: 2019: 2014: 1997: 1993: 1986: 1983: 1960: 1957: 1951: 1948: 1941: 1940: 1939: 1937: 1921: 1918: 1915: 1910: 1900: 1895: 1885: 1882: 1875: 1871: 1867: 1863: 1860:of dimension 1859: 1854: 1850: 1846: 1842: 1838: 1834: 1830: 1824: 1820: 1810: 1793: 1785: 1782: 1779: 1774: 1766: 1760: 1752: 1749: 1744: 1731: 1727: 1722: 1720: 1716: 1712: 1707: 1705: 1701: 1698: 1694: 1690: 1686: 1682: 1678: 1674: 1670: 1666: 1662: 1657: 1655: 1637: 1632: 1619: 1601: 1596: 1584: 1580: 1576: 1572: 1568: 1558: 1556: 1552: 1548: 1544: 1539: 1538: 1532: 1527: 1525: 1521: 1516: 1512: 1508: 1503: 1501: 1496: 1469: 1466: 1452: 1449:-dimensional 1448: 1444: 1440: 1436: 1432: 1428: 1424: 1420: 1416: 1412: 1402: 1387: 1384: 1380: 1377: 1355: 1345: 1340: 1312: 1309: 1305: 1302: 1281: 1278: 1269: 1249: 1244: 1215: 1198: 1171: 1167: 1164: 1155: 1148: 1147:connected sum 1131: 1128: 1124: 1121: 1113: 1109: 1105: 1100: 1098: 1094: 1090: 1086: 1082: 1079: 1078:pair of pants 1075: 1071: 1067: 1063: 1059: 1050: 1046: 1044: 1040: 1034: 1027: 1021: 1017: 1012: 1006: 1002: 1001:unit interval 992: 990: 986: 979: 975: 968: 964: 960: 956: 952: 948: 944: 939: 937: 933: 929: 925: 921: 917: 898: 895: 892: 889: 886: 860: 851: 845: 842: 836: 830: 827: 824: 814: 813: 812: 798: 789: 786: 783: 763: 754: 751: 748: 741: 725: 705: 685: 665: 642: 639: 636: 610: 607: 604: 601: 598: 595: 592: 589: 586: 576: 572: 569:-dimensional 553: 550: 547: 530: 513: 510: 499: 495: 479: 456: 436: 413: 407: 404: 399: 395: 391: 386: 376: 368: 364: 360: 357: 354: 349: 345: 331: 330: 329: 328: 324: 320: 304: 299: 285: 281: 277: 274: 270: 267: 264:-dimensional 263: 248: 246: 242: 238: 234: 230: 228: 223: 219: 215: 211: 207: 203: 202:homeomorphism 199: 195: 194:homeomorphism 191: 186: 172: 169: 166: 163: 160: 149: 145: 141: 137: 133: 129: 124: 122: 118: 114: 110: 105: 101: 97: 94: 90: 85: 83: 79: 75: 71: 67: 66: 61: 57: 54: 50: 46: 42: 34: 30: 26: 23:A cobordism ( 21: 9391:Publications 9256:Chern number 9246:Betti number 9224: 9129: / 9120:Key concepts 9068:Differential 8952: 8946: 8931: 8906: 8898: 8888: 8872: 8860: 8850: 8840: 8830: 8826: 8807: 8801: 8798:Milnor, John 8771: 8742: 8729: 8713: 8698: 8653: 8649: 8639: 8620: 8614: 8609:, chapter 12 8583: 8577: 8569: 8565: 8561: 8557: 8552: 8539: 8530: 8489: 8442: 8423: 8413: 8409: 8405: 8394: 8390: 8384: 8379: 8375: 8368: 8354: 8347: 8343: 8341:Thom spectra 8338: 8323: 8190: 8143: 8140: 7961: 7954: 7946: 7942: 7940: 7935: 7931: 7927: 7923: 7919: 7915: 7911: 7907: 7903: 7899: 7895: 7891: 7887: 7883: 7879: 7875: 7871: 7867: 7863: 7859: 7855: 7851: 7847: 7843: 7737: 7688: 7639: 7539: 7529: 7525: 7474: 7352: 7345: 7343: 7255: 7251: 7245: 7013: 6970: 6874: 6782: 6743: 6741: 6697: 6693: 6689: 6685: 6646: 6642: 6638: 6634: 6628: 6582: 6571: 6567: 6551: 6545: 6541: 6533: 6529: 6525: 6521: 6517: 6513: 6506: 6502: 6450: 6446: 6442: 6438: 6434: 6430: 6426: 6419: 6409: 6402: 6398: 6394: 6390: 6386: 6382: 6378: 6374: 6363:Grassmannian 6358: 6316: 6304: 6302: 6116: 6001: 5778: 5755: 5663: 5621: 5618: 5352: 5343: 5276: 5274: 5165: 5086: 4786: 4668: 4664: 4660: 4592: 4426: 4418: 4410: 4406: 4361: 4354: 4103: 4049: 3932: 3928: 3923:); it is an 3857: 3855: 3840: 3821: 3812: 3808: 3804: 3796: 3792: 3788: 3784: 3779: 3775: 3771: 3767: 3763: 3759: 3755: 3749: 3721: 3707:, alongside 3701:Thom complex 3686: 3663: 3653: 3649: 3645: 3637: 3635: 3583: 3579: 3575: 3518: 3514: 3344: 3336: 3332: 3328: 3324: 3320: 3316: 3312: 3308: 3304: 3300: 3296: 3292: 3288: 3284: 3280: 3276: 3272: 3268: 3264: 3262: 3252: 3248: 3244: 3240: 3236: 3232: 3228: 3224: 3220: 3216: 3212: 3208: 3204: 3200: 3196: 3188: 3186: 3175:Klein bottle 2794: 2627: 2599: 2594: 2525: 2521: 2517: 2513: 2509: 2505: 2503: 2368: 2366: 2106:obtained by 2105: 1935: 1869: 1865: 1861: 1857: 1855: 1848: 1844: 1840: 1836: 1832: 1828: 1822: 1818: 1816: 1723: 1708: 1696: 1688: 1684: 1680: 1676: 1672: 1668: 1664: 1660: 1658: 1582: 1564: 1554: 1550: 1546: 1542: 1530: 1528: 1523: 1519: 1514: 1510: 1504: 1499: 1498:The general 1497: 1446: 1438: 1434: 1430: 1426: 1422: 1418: 1414: 1410: 1408: 1111: 1107: 1103: 1101: 1096: 1092: 1088: 1084: 1080: 1073: 1069: 1065: 1057: 1055: 1042: 1038: 1032: 1025: 1019: 1015: 1010: 1004: 998: 988: 984: 977: 973: 966: 962: 958: 954: 950: 946: 942: 940: 935: 931: 927: 923: 919: 915: 875: 698:-manifolds 570: 536: 428: 322: 280:homeomorphic 268: 261: 259: 226: 222:Morse theory 187: 147: 143: 139: 135: 131: 127: 125: 103: 99: 95: 88: 86: 81: 73: 69: 63: 44: 38: 32: 28: 24: 9354:Wikiversity 9271:Key results 8869:"Cobordism" 8352:Thom spaces 6538:G-structure 6309:G-structure 5779:Therefore, 2610:John Milnor 2508:cobordism ( 2504:defines an 1934:define the 1715:normal maps 1581:called the 1579:graded ring 1571:G-structure 1405:Terminology 922:are called 229:-cobordisms 41:mathematics 9406:Categories 9200:CW complex 9141:Continuity 9131:Closed set 9090:cohomology 8911:S. Novikov 8768:Madsen, Ib 8689:References 8445:-cobordism 6562:spin group 6418:with maps 4840:such that 4478:. In 1954 4425:. Thus if 4102:for every 3782: â€Č âˆȘ 3770: â€Č; 3699:, via the 3457:and the 2- 3177:(Fig. 2c). 2506:elementary 1938:-manifold 1443:handlebody 1417:is called 1413:-manifold 740:embeddings 678:; closed 533:Cobordisms 327:half-space 251:Definition 9379:geometric 9374:algebraic 9225:Cobordism 9161:Hausdorff 9156:connected 9073:Geometric 9063:Continuum 9053:Algebraic 8997:B-Bordism 8969:0003-486X 8928:RenĂ© Thom 8879:EMS Press 8816:0013-8584 8810:: 16–23. 8720:EMS Press 8710:"bordism" 8670:0003-486X 8364:over the 8281:Ω 8240:∑ 8213:Ω 8157:Ω 8108:∗ 8100:↦ 8059:→ 8036:Ω 7930:, and to 7858:a closed 7810:Ω 7767:Ω 7749:Ω 7709:∗ 7700:Ω 7685:covariant 7655:∗ 7651:Ω 7606:Ω 7565:Ω 7507:→ 7490:Ω 7483:σ 7416:× 7413:⋯ 7410:× 7369:σ 7313:σ 7288:∈ 7248:signature 7194:Ω 7160:Ω 7128:Ω 7096:Ω 7064:Ω 7030:Ω 6988:∗ 6984:Ω 6942:Ω 6938:∈ 6849:⩾ 6843:∣ 6809:⊗ 6799:∗ 6795:Ω 6759:∗ 6755:Ω 6717:− 6711:⊔ 6684:, where − 6666:− 6660:⊔ 6596:∗ 6592:Ω 6520:), where 6479:→ 6467:~ 6464:ν 6265:⁡ 6245:χ 6242:↦ 6205:→ 6158:χ 6146:χ 6134:× 6125:χ 6069:∈ 6033:→ 6010:χ 5943:× 5940:⋯ 5937:× 5896:χ 5869:∈ 5853:⋯ 5807:→ 5787:χ 5735:χ 5721:⁡ 5707:− 5701:− 5682:∂ 5678:χ 5645:∈ 5633:χ 5546:⊕ 5275:For even 5189:∈ 5114:∈ 5060:∈ 5014:⋯ 4934:⋯ 4861:⋯ 4825:− 4812:≠ 4800:⩾ 4755:⋯ 4700:∈ 4644:− 4631:≠ 4570:− 4557:≠ 4545:⩾ 4502:∗ 4480:RenĂ© Thom 4452:∈ 4379:∈ 4321:⩾ 4314:⨁ 4305:∗ 4264:× 4135:× 4126:∂ 4117:⊔ 4087:∅ 4033:∅ 3973:⊔ 3900:Ω 3732:morphisms 3693:RenĂ© Thom 3606:× 3556:⊂ 3541:× 3486:× 3395:− 3380:× 3239: := 3223: := 3211: := 3149:× 3098:× 3051:× 3007:× 2953:× 2909:× 2859:× 2815:× 2692:× 2648:× 2606:RenĂ© Thom 2575:⊂ 2567:− 2554:× 2472:× 2435:× 2420:× 2404:∪ 2394:× 2339:− 2326:× 2300:∂ 2289:− 2276:× 2241:× 2221:∂ 2193:− 2180:× 2130:× 2081:− 2068:× 2033:− 2020:× 1998:φ 1994:∪ 1987:φ 1984:⁡ 1961:− 1916:⊂ 1901:× 1883:φ 1874:embedding 1775:∗ 1771:Ω 1745:∗ 1741:Ω 1633:∗ 1629:Ω 1597:∗ 1593:Ω 1543:Cobordism 1529:The term 1515:cobordism 1381:⊔ 1346:× 1306:⊔ 1274:# 1205:# 1160:# 1125:⊔ 1041:× {0} to 930:form the 924:cobordant 843:⊔ 822:∂ 796:∂ 793:↪ 787:: 761:∂ 758:↪ 752:: 575:quintuple 571:cobordism 517:∅ 508:∂ 477:∂ 405:⩾ 392:∣ 377:∈ 358:… 256:Manifolds 170:⊔ 158:∂ 128:cobordism 109:RenĂ© Thom 76:if their 74:cobordant 70:cobordism 68:, giving 56:manifolds 45:cobordism 9344:Wikibook 9322:Category 9210:Manifold 9178:Homotopy 9136:Interior 9127:Open set 9085:Homology 9034:Topology 8739:(1989). 8538:(1968). 8436:See also 7914: : 7870: : 7550:K-theory 6688:denotes 6631:oriented 6449:+1), an 5056:⟩ 4984:⟨ 4976:⟩ 4904:⟨ 3752:category 3724:category 3709:K-theory 3670:homology 3279: : 2616:Examples 1691:= U for 1567:oriented 1561:Variants 1507:fillings 1388:′ 1313:′ 1282:′ 1168:′ 1132:′ 995:Examples 934:of  266:manifold 93:manifold 82:boundary 62:(French 60:boundary 9369:general 9171:uniform 9151:compact 9102:Digital 8991:Bordism 8977:1970136 8678:1970136 8606:1886843 8360:of the 7896:bordant 7854:) with 7844:bordism 7801:. Then 7548:called 7351:, ..., 6971:of the 6369:of the 6361:to the 4482:proved 3836:functor 3766:) and ( 3728:objects 3660:History 3195:on an ( 2791:Fig. 2b 2783:Fig. 2a 2108:surgery 1872:and an 1721:class. 1719:bordism 1531:bordism 1511:Bordism 1045:× {1}. 983:, then 498:compact 276:locally 80:is the 53:compact 9364:Topics 9166:metric 9041:Fields 8975:  8967:  8917:  8814:  8786:  8751:  8676:  8668:  8627:  8604:  8594:  7949:has a 7894:) are 7540:Every 6564:, the 6560:, the 4225:, the 4106:since 3801:cospan 3678:p. 289 3421:sphere 3341:handle 3295:(1) = 3287:(0) = 2624:Fig. 1 1974:  1835:) = (∂ 1697:stably 1695:using 1064:, and 1062:circle 1035:× {1} 1028:× {0} 858:  738:; and 239:, and 224:, and 98:is an 9146:Space 8973:JSTOR 8674:JSTOR 8481:Notes 7532:= 1. 6373:: Îœ: 5087:with 4355:is a 3826:is a 3513:with 3459:torus 3191:is a 3128:torus 2369:trace 1843:) âˆȘ ( 573:is a 271:is a 220:with 8965:ISSN 8915:ISBN 8812:ISSN 8784:ISBN 8749:ISBN 8666:ISSN 8625:ISBN 8592:ISBN 8564:and 8428:and 8378:and 7886:), ( 7732:are 7683:are 7358:≄ 1 7246:The 6528:) → 6441:) → 6393:) → 5622:The 5239:the 5172:and 5164:the 3931:and 3574:and 2608:and 2367:The 1728:and 1675:and 1549:and 1537:bord 1513:and 1095:and 1087:and 1072:and 987:and 972:and 918:and 212:and 146:and 134:and 119:and 111:for 65:bord 8957:doi 8658:doi 8558:not 8410:MSO 8376:MSO 8336:). 7941:An 7934:on 7926:on 7736:in 7687:in 6700:is 6550:SO( 6262:dim 5718:dim 5168:th 4785:of 4417:of 4285:so 2839:or 1847:× ∂ 1409:An 1370:in 1056:If 1013:, ( 959:not 957:is 537:An 529:.) 200:or 192:or 39:In 9408:: 8971:. 8963:. 8953:72 8934:, 8930:, 8897:, 8887:, 8877:, 8871:, 8859:, 8849:, 8839:, 8831:31 8825:, 8806:. 8782:. 8778:: 8774:. 8728:, 8718:, 8712:, 8697:, 8672:. 8664:. 8654:72 8652:. 8648:. 8602:MR 8600:, 8590:, 8416:. 8414:MO 8406:MO 8393:= 8391:MO 8389:– 8380:MO 8369:BG 8355:MG 8344:MG 8299:pt 7953:∈ 7938:. 7918:→ 7906:, 7902:; 7890:, 7882:, 7874:→ 7850:, 7785:pt 7502:SO 7460:1. 7341:. 7203:SO 7169:SO 7137:SO 7105:SO 7073:SO 7039:SO 6993:SO 6954:SO 6804:SO 6764:SO 6739:. 6641:, 6637:, 6615:. 6580:. 6544:= 6514:BG 6443:BO 6435:BO 6427:BO 6425:→ 6416:+1 6408:→ 6395:BO 6385:, 6379:Gr 6377:→ 6103:1. 5987:1. 5776:. 5600:2. 5350:. 5272:. 4667:, 3822:A 3819:. 3811:← 3807:→ 3803:: 3795:, 3791:; 3774:, 3762:, 3758:; 3742:. 3719:. 3676:, 3652:, 3648:; 3582:× 3347:. 3319:, 3315:; 3291:, 3271:, 3267:; 3251:, 3247:; 2612:. 2604:, 2597:. 2516:, 2512:; 2385::= 1952::= 1868:+ 1864:= 1853:. 1839:× 1831:× 1827:∂( 1821:, 1706:. 1656:. 1526:. 1509:. 1110:, 1030:, 1023:; 1018:× 1007:= 938:. 914:. 776:, 718:, 317:A 247:. 185:. 150:, 126:A 123:. 43:, 35:). 31:, 27:; 9026:e 9019:t 9012:v 8979:. 8959:: 8923:. 8818:. 8808:8 8792:. 8757:. 8680:. 8660:: 8633:. 8570:W 8566:N 8562:M 8546:. 8513:) 8510:1 8507:+ 8504:n 8501:( 8443:h 8404:( 8402:∗ 8399:π 8397:( 8395:H 8371:n 8357:n 8348:G 8309:. 8306:) 8303:) 8295:( 8290:G 8285:q 8277:; 8274:X 8271:( 8266:p 8262:H 8256:n 8253:= 8250:q 8247:+ 8244:p 8236:= 8233:) 8230:X 8227:( 8222:G 8217:n 8191:X 8177:) 8174:X 8171:( 8166:n 8161:G 8119:] 8116:M 8113:[ 8104:f 8097:) 8094:f 8091:, 8088:M 8085:( 8078:) 8075:X 8072:( 8067:n 8063:H 8056:) 8053:X 8050:( 8045:G 8040:n 8029:{ 8003:Z 7982:2 7978:/ 7973:Z 7962:M 7960:( 7957:n 7955:H 7947:M 7943:n 7936:N 7932:g 7928:M 7924:f 7920:X 7916:W 7912:h 7908:N 7904:M 7900:W 7892:g 7888:N 7884:f 7880:M 7876:X 7872:M 7868:f 7864:M 7860:n 7856:M 7852:f 7848:M 7830:) 7827:X 7824:( 7819:G 7814:n 7789:) 7781:( 7776:G 7771:n 7763:= 7758:G 7753:n 7738:X 7720:) 7717:X 7714:( 7704:G 7689:X 7671:) 7668:X 7665:( 7660:G 7640:X 7626:) 7623:X 7620:( 7615:n 7610:G 7585:) 7582:X 7579:( 7574:G 7569:n 7530:i 7526:i 7511:Z 7497:i 7494:4 7486:: 7457:= 7453:) 7449:) 7445:C 7441:( 7434:k 7430:i 7426:2 7421:P 7407:) 7403:C 7399:( 7392:1 7388:i 7384:2 7379:P 7373:( 7355:k 7353:i 7349:1 7346:i 7325:. 7322:) 7319:M 7316:( 7292:Z 7285:) 7282:M 7279:( 7274:i 7271:2 7267:H 7256:M 7252:i 7227:. 7222:2 7217:Z 7212:= 7198:5 7186:, 7182:Z 7178:= 7164:4 7152:, 7149:0 7146:= 7132:3 7120:, 7117:0 7114:= 7100:2 7088:, 7085:0 7082:= 7068:1 7056:, 7052:Z 7048:= 7034:0 6949:i 6946:4 6934:] 6930:) 6926:C 6922:( 6917:i 6914:2 6909:P 6903:[ 6899:= 6894:i 6891:4 6887:y 6860:, 6856:] 6852:1 6846:i 6838:i 6835:4 6831:y 6826:[ 6821:Q 6817:= 6813:Q 6769:. 6744:M 6723:) 6720:M 6714:( 6708:M 6698:I 6694:M 6690:N 6686:N 6672:) 6669:N 6663:( 6657:M 6643:N 6639:M 6635:W 6601:G 6574:) 6572:k 6570:( 6568:U 6554:) 6552:k 6546:O 6542:G 6534:k 6532:( 6530:O 6526:k 6524:( 6522:G 6518:k 6516:( 6509:k 6507:X 6503:X 6487:k 6483:X 6476:M 6473:: 6451:X 6447:k 6445:( 6439:k 6437:( 6431:k 6429:( 6422:k 6420:X 6412:k 6410:X 6405:k 6403:X 6399:k 6397:( 6391:k 6387:n 6383:n 6381:( 6375:M 6359:M 6343:k 6340:+ 6337:n 6332:R 6317:M 6305:X 6274:) 6271:M 6268:( 6258:x 6254:) 6251:M 6248:( 6239:] 6236:M 6233:[ 6226:] 6223:x 6220:[ 6215:2 6210:F 6200:N 6192:{ 6167:) 6164:N 6161:( 6155:) 6152:M 6149:( 6143:= 6140:) 6137:N 6131:M 6128:( 6100:= 6097:i 6077:, 6073:N 6066:i 6046:2 6042:/ 6037:Z 6028:i 6025:2 6019:N 6013:: 5984:= 5980:) 5976:) 5972:R 5968:( 5961:k 5957:i 5953:2 5948:P 5934:) 5930:R 5926:( 5919:1 5915:i 5911:2 5906:P 5900:( 5873:N 5864:k 5860:i 5856:, 5850:, 5845:1 5841:i 5820:2 5816:/ 5811:Z 5802:i 5796:N 5790:: 5764:W 5739:W 5730:) 5724:W 5714:) 5710:1 5704:( 5698:1 5694:( 5690:= 5685:W 5664:M 5649:Z 5642:) 5639:M 5636:( 5596:/ 5591:Z 5587:= 5578:5 5572:N 5562:, 5559:2 5555:/ 5550:Z 5543:2 5539:/ 5534:Z 5530:= 5521:4 5515:N 5505:, 5502:0 5499:= 5490:3 5484:N 5474:, 5471:2 5467:/ 5462:Z 5458:= 5449:2 5443:N 5433:, 5430:0 5427:= 5418:1 5412:N 5402:, 5399:2 5395:/ 5390:Z 5386:= 5377:0 5371:N 5344:i 5329:] 5325:) 5321:R 5317:( 5312:i 5307:P 5301:[ 5297:= 5292:i 5288:x 5277:i 5254:2 5249:F 5226:) 5220:2 5215:F 5210:; 5207:M 5203:( 5197:n 5193:H 5186:] 5183:M 5180:[ 5166:i 5151:) 5145:2 5140:F 5135:; 5132:M 5128:( 5122:i 5118:H 5111:) 5108:M 5105:( 5100:i 5096:w 5070:2 5065:F 5052:] 5049:N 5046:[ 5043:, 5040:) 5037:N 5034:( 5027:k 5023:i 5018:w 5011:) 5008:N 5005:( 4998:1 4994:i 4989:w 4980:= 4972:] 4969:M 4966:[ 4963:, 4960:) 4957:M 4954:( 4947:k 4943:i 4938:w 4931:) 4928:M 4925:( 4918:1 4914:i 4909:w 4880:n 4877:= 4872:k 4868:i 4864:+ 4858:+ 4853:1 4849:i 4828:1 4820:j 4816:2 4809:i 4806:, 4803:1 4797:i 4787:k 4772:) 4766:k 4762:i 4758:, 4752:, 4747:1 4743:i 4738:( 4717:, 4712:n 4706:N 4697:] 4694:N 4691:[ 4688:= 4685:] 4682:M 4679:[ 4669:N 4665:M 4661:n 4647:1 4639:j 4635:2 4628:i 4606:i 4602:x 4577:] 4573:1 4565:j 4561:2 4554:i 4551:, 4548:1 4542:i 4538:| 4532:i 4528:x 4523:[ 4517:2 4512:F 4507:= 4496:N 4464:n 4458:N 4449:0 4446:= 4443:] 4440:M 4437:[ 4427:M 4419:M 4411:M 4407:n 4391:n 4385:N 4376:] 4373:M 4370:[ 4338:n 4332:N 4324:0 4318:n 4310:= 4299:N 4273:, 4270:] 4267:N 4261:M 4258:[ 4255:= 4252:] 4249:N 4246:[ 4243:] 4240:M 4237:[ 4211:2 4206:F 4182:n 4176:N 4153:) 4150:] 4147:1 4144:, 4141:0 4138:[ 4132:M 4129:( 4123:= 4120:M 4114:M 4104:M 4090:] 4084:[ 4081:= 4078:] 4075:M 4072:[ 4069:+ 4066:] 4063:M 4060:[ 4050:n 4036:] 4030:[ 4008:n 4002:N 3979:] 3976:N 3970:M 3967:[ 3964:= 3961:] 3958:N 3955:[ 3952:+ 3949:] 3946:M 3943:[ 3933:N 3929:M 3909:O 3904:n 3877:n 3871:N 3858:n 3813:N 3809:W 3805:M 3797:P 3793:M 3789:W 3785:N 3780:W 3776:P 3772:N 3768:W 3764:N 3760:M 3756:W 3654:N 3650:M 3646:W 3638:f 3621:. 3616:2 3611:D 3601:1 3596:D 3584:I 3580:M 3576:W 3562:, 3559:M 3551:2 3546:D 3536:0 3531:S 3519:M 3515:N 3501:, 3496:1 3491:S 3481:1 3476:S 3471:= 3468:N 3443:2 3438:S 3433:= 3430:M 3405:3 3400:D 3390:2 3385:D 3375:1 3370:S 3365:= 3362:W 3345:f 3337:M 3333:W 3329:f 3325:M 3321:N 3317:M 3313:W 3309:f 3305:W 3301:f 3297:N 3293:f 3289:M 3285:f 3281:W 3277:f 3273:N 3269:M 3265:W 3253:N 3249:M 3245:W 3241:f 3237:W 3233:p 3229:c 3227:( 3225:f 3221:M 3217:c 3215:( 3213:f 3209:N 3205:p 3201:c 3197:n 3189:f 3159:1 3154:S 3144:1 3139:S 3113:. 3108:1 3103:D 3093:1 3088:S 3066:, 3061:2 3056:D 3046:0 3041:S 3017:2 3012:D 3002:0 2997:S 2963:2 2958:D 2948:0 2943:S 2919:1 2914:D 2904:1 2899:S 2874:. 2869:1 2864:D 2854:1 2849:S 2825:2 2820:D 2810:0 2805:S 2763:1 2758:S 2734:1 2729:S 2707:. 2702:0 2697:S 2687:1 2682:D 2658:1 2653:D 2643:0 2638:S 2581:. 2578:N 2570:1 2564:q 2559:S 2549:1 2546:+ 2543:p 2538:D 2526:N 2522:M 2518:N 2514:M 2510:W 2488:) 2482:q 2477:D 2467:1 2464:+ 2461:p 2456:D 2450:( 2444:} 2441:1 2438:{ 2430:q 2425:D 2415:p 2410:S 2400:) 2397:I 2391:M 2388:( 2382:W 2352:. 2348:) 2342:1 2336:q 2331:S 2321:1 2318:+ 2315:p 2310:D 2304:( 2297:= 2292:1 2286:q 2281:S 2271:p 2266:S 2261:= 2257:) 2251:q 2246:D 2236:p 2231:S 2225:( 2196:1 2190:q 2185:S 2175:1 2172:+ 2169:p 2164:D 2140:q 2135:D 2125:p 2120:S 2090:) 2084:1 2078:q 2073:S 2063:1 2060:+ 2057:p 2052:D 2046:( 2036:1 2030:q 2025:S 2015:p 2010:S 2003:| 1990:) 1980:m 1977:i 1971:t 1968:n 1965:i 1958:M 1955:( 1949:N 1936:n 1922:, 1919:M 1911:q 1906:D 1896:p 1891:S 1886:: 1870:q 1866:p 1862:n 1858:M 1851:) 1849:Y 1845:X 1841:Y 1837:X 1833:Y 1829:X 1823:Y 1819:X 1797:) 1794:X 1791:( 1786:P 1783:O 1780:T 1767:, 1764:) 1761:X 1758:( 1753:L 1750:P 1689:G 1685:G 1681:G 1677:N 1673:M 1669:G 1665:W 1661:G 1638:G 1602:G 1551:N 1547:M 1483:) 1479:R 1475:( 1470:n 1467:2 1462:P 1447:n 1439:n 1435:n 1431:n 1427:M 1423:M 1415:M 1411:n 1385:M 1378:M 1356:n 1351:D 1341:0 1336:S 1310:M 1303:M 1279:M 1270:M 1250:. 1245:1 1240:S 1216:1 1211:S 1199:1 1194:S 1172:. 1165:M 1156:M 1129:M 1122:M 1112:M 1108:M 1104:n 1097:N 1093:M 1089:N 1085:M 1081:W 1074:N 1070:M 1066:N 1058:M 1043:M 1039:M 1033:M 1026:M 1020:I 1016:M 1011:M 1005:I 989:N 985:M 981:2 978:W 974:N 970:1 967:W 963:M 955:W 951:W 947:M 943:M 936:M 928:M 920:N 916:M 902:) 899:N 896:, 893:M 890:; 887:W 884:( 861:. 855:) 852:N 849:( 846:j 840:) 837:M 834:( 831:i 828:= 825:W 799:W 790:N 784:j 764:W 755:M 749:i 726:N 706:M 686:n 666:W 646:) 643:1 640:+ 637:n 634:( 614:) 611:j 608:, 605:i 602:, 599:N 596:, 593:M 590:; 587:W 584:( 557:) 554:1 551:+ 548:n 545:( 514:= 511:M 480:M 457:M 437:M 414:. 411:} 408:0 400:n 396:x 387:n 382:R 374:) 369:n 365:x 361:, 355:, 350:1 346:x 342:( 339:{ 323:M 305:. 300:n 295:R 269:M 262:n 227:h 173:N 167:M 164:= 161:W 148:N 144:M 140:W 136:N 132:M 104:W 100:n 96:W 89:n 33:N 29:M 25:W

Index


mathematics
equivalence relation
compact
manifolds
boundary
bord
disjoint union
manifold
René Thom
smooth manifolds
piecewise linear
topological manifolds
diffeomorphism
homeomorphism
diffeomorphism
homeomorphism
word problem for groups
geometric topology
algebraic topology
intimately connected
Morse theory
h-cobordisms
surgery theory
extraordinary cohomology theories
categories of cobordisms
topological quantum field theories
manifold
topological space
locally

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