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Compactly generated space

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By itself, Definition 3 is not quite as useful as the other two definitions as it lacks some of the properties implied by the others. For example, every quotient space of a space satisfying Definition 1 or Definition 2 is a space of the same kind. But that does not hold for Definition 3.
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section, there is no universally accepted definition in the literature for compactly generated spaces; but Definitions 1, 2, 3 from that section are some of the more commonly used. In order to express results in a more concise way, this section will make use of the abbreviations
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on a set induced by a family of functions from CG-1 spaces is also CG-1. And the same holds for CG-2. This follows by combining the results above for disjoint unions and quotient spaces, together with the behavior of final topologies under composition of functions.
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in a manner made precise below. There is in fact no commonly agreed upon definition for such spaces, as different authors use variations of the definition that are not exactly equivalent to each other. Also some authors include some separation axiom (like
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A quotient space of a CG-3 space is not CG-3 in general. In fact, every CG-2 space is a quotient space of a CG-3 space (namely, some locally compact Hausdorff space); but there are CG-2 spaces that are not CG-3. For a concrete example, the
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need not be a CW-complex. By contrast, the category of simplicial sets had many convenient properties, including being cartesian closed. The history of the study of repairing this situation is given in the article on the
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For coherent spaces, that corresponds to showing that the space is coherent with a subfamily of the family of subspaces. For example, this provides one way to show that locally compact spaces are compactly generated.
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Compactly generated Hausdorff spaces include the Hausdorff version of the various classes of spaces mentioned above as CG-1 or CG-2, namely Hausdorff sequential spaces, Hausdorff first countable spaces,
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In a CG-1 space, every closed set is CG-1. The same does not hold for open sets. For instance, as shown in the Examples section, there are many spaces that are not CG-1, but they are open in their
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The equivalence between conditions (1) and (2) follows from the fact that every inclusion from a subspace is a continuous map; and on the other hand, every continuous map
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to denote each of the three definitions unambiguously. This is summarized in the table below (see the Definitions section for other equivalent conditions for each).
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Informally, a space whose topology is determined by its compact subspaces, or equivalently in this case, by all continuous maps from arbitrary compact spaces.
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article, condition (1) is well-defined, even though the family of continuous maps from arbitrary compact Hausdorff spaces is not a set but a proper class.
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from the real line with the positive integers identified to a point is sequential. Both spaces are compactly generated Hausdorff, but their product
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Every CG-3 space is CG-2 and every CG-2 space is CG-1. The converse implications do not hold in general, as shown by some of the examples below.
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article, condition (2) is well-defined, even though the family of continuous maps from arbitrary compact spaces is not a set but a proper class.
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These ideas can be generalized to the non-Hausdorff case. This is useful since identification spaces of Hausdorff spaces need not be Hausdorff.
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of CG-1 spaces is CG-1. The same holds for CG-2. This is also an application of the results above for disjoint unions and quotient spaces.
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can also be defined by pairing the weak Hausdorff property with Definition 3, which may be easier to state and work with than Definition 2.
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is compactly generated according to one of the definitions in this article. Since compactly generated spaces are defined in terms of a
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These ideas generalize to the non-Hausdorff case; i.e. with a different definition of compactly generated spaces. This is useful since
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is given below. Another suggestion (1964) was to consider the usual Hausdorff spaces but use functions continuous on compact subsets.
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Subspaces of a compactly generated space are not compactly generated in general, even in the Hausdorff case. For example, the
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is in the sense of condition (3) in the corresponding article, namely each point has a local base of compact neighborhoods.)
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https://math.stackexchange.com/questions/4646084/unraveling-the-various-definitions-of-k-space-or-compactly-generated-space
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The continuous functions on compactly generated spaces are those that behave well on compact subsets. More precisely, let
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Informally, a space whose topology is determined by all continuous maps from arbitrary compact Hausdorff spaces.
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with respect to this family of maps. And other variations of the definition replace compact spaces with compact
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Every space satisfying Definition 3 also satisfies Definition 2. The converse is not true. For example, the
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Every space satisfying Definition 2 also satisfies Definition 1. The converse is not true. For example, the
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Definition 2 is the one more commonly used in algebraic topology. This definition is often paired with the
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for example all compact subspaces, or all compact Hausdorff subspaces. This corresponds to choosing a set
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in the literature. These definitions share a common structure, starting with a suitably specified family
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of two compactly generated spaces need not be compactly generated, even if both spaces are Hausdorff and
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space is CG-2. Conversely, every CG-2 space is the quotient space of a locally compact Hausdorff space.
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is also a quotient map on a locally compact Hausdorff space). The same is true more generally for every
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Below are some of the more commonly used definitions in more detail, in increasing order of specificity.
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Another choice is to take the family of all continuous maps from arbitrary spaces of a certain type into
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Topology same as final topology with respect to continuous maps from arbitrary compact Hausdorff spaces
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with the various maps in the family used to define the final topology. The specifics are as follows.
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of compactly generated Hausdorff spaces, which is in fact cartesian closed. These ideas extend on the
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for example all such maps from arbitrary compact spaces, or from arbitrary compact Hausdorff spaces.
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The motivation for their deeper study came in the 1960s from well known deficiencies of the usual
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is unambiguous and refers to a compactly generated space (in any of the definitions) that is also
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is compact, hence CG-1. But it is not CG-2 because open subspaces inherit the CG-2 property and
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For Hausdorff spaces the properties CG-1, CG-2, CG-3 are equivalent. Such spaces can be called
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is compact Hausdorff, hence compactly generated. Its subspace with all limit ordinals except
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As an additional general note, a sufficient condition that can be useful to show that a space
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while still containing the typical spaces of interest, which makes them convenient for use in
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However, in some cases the product of two compactly generated spaces is compactly generated:
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are the closed sets in its k-ification, with a corresponding characterization. In the space
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that is not CG-1 (for example the Arens-Fort space or an uncountable product of copies of
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does not satisfy Definition 3, because its compact Hausdorff subspaces are the singletons
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To provide examples of spaces that are not compactly generated, it is useful to examine
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with the family of its compact Hausdorff subspaces; namely, it satisfies the property:
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coincide, and the induced topologies on compact subsets are the same. It follows that
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The first suggestion (1962) to remedy this situation was to restrict oneself to the
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Informally, a space whose topology is determined by its compact Hausdorff subspaces.
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is compact and hence satisfies Definition 1, but it does not satisfies Definition 2.
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A quotient space of a CG-2 space is CG-2. In particular, every quotient space of a
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every closed set is CG-2; and so is every open set (because there is a quotient map
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Compactly generated spaces were developed to remedy some of the shortcomings of the
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of compactly generated spaces (like all CG-1 spaces or all CG-2 spaces), the usual
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is the quotient space of a weakly locally compact space, which can be taken as the
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For examples of spaces that are CG-1 and not CG-2, one can start with any space
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For Hausdorff spaces, all three definitions are equivalent. So the terminology
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Other examples of (Hausdorff) spaces that are not compactly generated include:
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with the family of its compact subspaces; namely, it satisfies the property:
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The one-point Lindelöfication of an uncountable discrete space (also called
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spaces, that is, spaces whose compact subspaces are all finite. If a space
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is equal to its k-ification; equivalently, if every k-open set is open in
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be a function from a topological space to another and suppose the domain
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The product of two first countable spaces is first countable, hence CG-2.
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is not CG-3, but is homeomorphic to the quotient of the compact interval
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Other definitions use a family of continuous maps from compact spaces to
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every open set is k-open and every closed set is k-closed. The space
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does belong to the expected category and is the categorical product.
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instead. On the other hand, it satisfies Definition 2 because it is
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with the family of its compact subspaces, meaning that for every set
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is CG-1. The corresponding statements also hold for CG-2 and CG-3.
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of a CG-1 space is CG-1. In particular, every quotient space of a
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Topology coherent with family of its compact Hausdorff subspaces
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set, that is, the intersection of an open set and a closed set.
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section for the meaning of the abbreviations CG-1, CG-2, CG-3.)
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spaces are CG-1, but not necessarily CG-2 (see examples below).
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has the discrete topology and the corresponding k-ification of
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and thus factors through the inclusion of the compact subspace
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These different choices for the family of continuous maps into
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is not always an identification map, and the usual product of
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spaces Definitions 2 and 3 are equivalent. Thus the category
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Lawson, J.; Madison, B. (1974). "Quotients of k-semigroups".
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The various definitions differ in their choice of the family
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to be compactly generated if its topology coincides with the
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is not compactly generated in general, so cannot serve as a
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if it satisfies any of the following equivalent conditions:
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if it satisfies any of the following equivalent conditions:
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category CGWH of compactly generated weak Hausdorff spaces
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category CGWH of compactly generated weak Hausdorff spaces
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of topological spaces is CG-1 if and only if each space
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is the discrete topology. Therefore, any anticompact T
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is the empty set or a single point, which is closed in
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its intersection with every compact Hausdorff subspace
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Topology coherent with family of its compact subspaces
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Pages displaying wikidata descriptions as a fallback
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Pages displaying wikidata descriptions as a fallback
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with objects the Hausdorff spaces. The functor from
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spaces the properties CG-2 and CG-3 are equivalent.
5841:{\displaystyle \mathbf {CGTop} \to \mathbf {Top} .} 3306:non-discrete space is not CG-1. Examples include: 688:. The open sets in the k-ification are called the 397:There are multiple (non-equivalent) definitions of 5990: 5970: 5946: 5919: 5883: 5840: 5782: 5759: 5739: 5705: 5677: 5643: 5605: 5576: 5535: 5515: 5492: 5460: 5440: 5417: 5397: 5374: 5348: 5325: 5298: 5262: 5242: 5222: 5199: 5166:that is compactly generated, sometimes called the 5158: 5134: 5102: 5063: 5039: 5019: 4999: 4964: 4941: 4914: 4885: 4843: 4823: 4801: 4766: 4746: 4705: 4685: 4663: 4634: 4589: 4569: 4546: 4526: 4498: 4478: 4438: 4399: 4336: 4306: 4238: 4133: 4101: 4055: 4028: 3997: 3970: 3924: 3867: 3828: 3808: 3782: 3762: 3730: 3689: 3658: 3631: 3550: 3530: 3510: 3490: 3463: 3443: 3421: 3393: 3364: 3294: 3274: 3250: 3181: 3161: 3138: 3112: 2964:, this property is most commonly coupled with the 2888:Compactly generated spaces were originally called 2858: 2823: 2783: 2757: 2731: 2687: 2643: 2614: 2594: 2568: 2548: 2506: 2441: 2414: 2390: 2355: 2335: 2315: 2276: 2256: 2227: 2204: 2180:with respect to the family of all continuous maps 2168: 2136: 2106: 2083: 2054: 2025: 2005: 1958: 1927: 1905: 1882: 1858:with respect to the family of all continuous maps 1846: 1822: 1793: 1773: 1747: 1727: 1694: 1662: 1612: 1585: 1565: 1531: 1507: 1476: 1452: 1429: 1406: 1373: 1353: 1327: 1307: 1273: 1253: 1230: 1206: 1183: 1157: 1125: 1102: 1079: 1059: 1035: 1003: 981: 955: 926: 906: 883: 855: 828: 796: 776: 737: 711: 680: 656: 636: 601: 577: 550: 526: 506: 471: 444: 421: 387: 360: 336: 268: 248: 228: 199: 179: 153: 129: 110: 49: 5614:with objects the compactly generated spaces, and 4534:in terms of the continuity of the composition of 4307:{\displaystyle Y=\mathbb {R} /\{1,2,3,\ldots \}} 3201:, is an example of CG-2 space that is not CG-3. 4754:is continuous for each compact Hausdorff space 1043:) if its topology is determined by all maps in 429:of continuous maps from some compact spaces to 6268:"The total negation of a topological property" 2799:to the quotient space of the compact interval 372:, that is, the collection of all open sets in 6739:reprint of 1978 ed.). Berlin, New York: 6460: 6400: 5007:denote the space of all continuous maps from 4851:is continuous if and only if the restriction 4016:space is CG-1. Conversely, every CG-1 space 1289:with that family of subspaces; namely, a set 8: 6298: 5194: 5181: 4862: 4611: 4301: 4277: 4233: 4193: 3098: 3092: 2778: 2772: 2752: 2746: 2726: 2717: 2711: 2702: 2682: 2670: 2235:In other words, it satisfies the condition: 1167:As for the different choices for the family 5468:was compactly generated to start with then 3882:In a CG-3 space, every closed set is CG-3. 2957:of Hausdorff spaces need not be Hausdorff. 6532: 6472: 6373: 6253: 6167: 6134: 6056: 3379:The product of uncountably many copies of 2831:obtained by identifying all the points in 6840:Convenient category of topological spaces 6448: 6334: 6283: 5983: 5963: 5938: 5932: 5908: 5896: 5861: 5859: 5824: 5804: 5802: 5772: 5752: 5720: 5718: 5692: 5690: 5658: 5656: 5621: 5619: 5592: 5590: 5557: 5555: 5528: 5505: 5473: 5453: 5430: 5410: 5387: 5382:One can show that the compact subsets of 5361: 5338: 5317: 5311: 5290: 5278: 5255: 5235: 5212: 5188: 5179: 5151: 5127: 5080: 5056: 5032: 5012: 4977: 4954: 4934: 4898: 4893:is continuous for each compact Hausdorff 4865: 4856: 4836: 4816: 4779: 4759: 4721: 4698: 4678: 4647: 4614: 4605: 4582: 4562: 4539: 4519: 4491: 4459: 4416: 4386: 4323: 4272: 4268: 4267: 4259: 4219: 4205: 4186: 4185: 4177: 4114: 4082: 4045: 4021: 3989: 3983: 3956: 3946: 3937: 3916: 3906: 3901: 3898: 3847: 3841: 3821: 3795: 3775: 3770:for some locally compact Hausdorff space 3743: 3720: 3681: 3675: 3650: 3644: 3620: 3592: 3586: 3543: 3523: 3503: 3480: 3456: 3437: 3436: 3434: 3414: 3387: 3386: 3384: 3358: 3357: 3355: 3287: 3267: 3243: 3174: 3151: 3125: 3090: 2836: 2804: 2770: 2744: 2700: 2662: 2627: 2607: 2581: 2561: 2535: 2499: 2434: 2407: 2368: 2348: 2328: 2295: 2289: 2269: 2243: 2217: 2185: 2161: 2129: 2096: 2067: 2038: 2018: 1986: 1951: 1920: 1895: 1863: 1839: 1806: 1786: 1760: 1740: 1714: 1687: 1655: 1601: 1600: 1598: 1578: 1557: 1556: 1547: 1546: 1544: 1523: 1522: 1520: 1500: 1469: 1445: 1419: 1395: 1394: 1386: 1366: 1340: 1320: 1294: 1266: 1243: 1222: 1221: 1219: 1196: 1175: 1174: 1172: 1138: 1115: 1092: 1072: 1051: 1050: 1048: 1027: 1026: 1024: 996: 968: 946: 945: 939: 919: 896: 876: 844: 843: 841: 809: 789: 756: 750: 724: 701: 673: 668:than (or equal to) the original topology 649: 614: 593: 592: 590: 567: 542: 541: 539: 519: 497: 496: 490: 460: 459: 457: 434: 413: 412: 410: 377: 353: 317: 261: 241: 212: 192: 166: 146: 122: 94: 42: 6657:. Chicago: University of Chicago Press. 6623:Categories for the Working Mathematician 6496: 6436: 6361: 6322: 5207:denote the family of compact subsets of 3231:are also Hausdorff compactly generated. 2999: 1515:is compactly generated (with respect to 6544: 6520: 6310: 6107: 6095: 6049: 4190: 1593:is compactly generated with respect to 6651:A Concise Course in Algebraic Topology 2732:{\displaystyle \{\emptyset ,\{1\},X\}} 1464:. Additionally, some authors require 1110:or if every k-closed set is closed in 6828:Compactly generated topological space 6424: 6412: 6207: 6147:compactly generated topological space 6122: 2622:for every compact Hausdorff subspace 308:General framework for the definitions 7: 6609:On the foundations of k-group theory 6508: 6484: 6385: 6220:Booth, Peter; Tillotson, J. (1980). 3705:, which is not compactly generated. 1484:to satisfy a separation axiom (like 1407:{\displaystyle K\in {\mathcal {C}}.} 1067:, in the sense that the topology on 3925:{\displaystyle {\coprod }_{i}X_{i}} 2968:property, so that one works in the 1631:compactly generated Hausdorff space 18:Compactly generated Hausdorff space 5543:(i.e., there are more open sets). 4886:{\displaystyle f\vert _{K}:K\to Y} 4635:{\displaystyle f\vert _{K}:K\to Y} 4365:The product of a CG-2 space and a 4354:The product of a CG-1 space and a 3338:The "Single ultrafilter topology". 2705: 2343:for every compact Hausdorff space 2212:from all compact Hausdorff spaces 25: 6630:(2nd ed.). Springer-Verlag. 5884:{\displaystyle \mathbf {CGHaus} } 5644:{\displaystyle \mathbf {CGHaus} } 5299:{\displaystyle A\cap K_{\alpha }} 4713:is continuous if and only if the 4597:is continuous if and only if the 3169:hence the singleton is closed in 3113:{\displaystyle \{x\}\subseteq X,} 3031: 3021: 3011: 1460:lead to different definitions of 65:if its topology is determined by 6626:. Graduate Texts in Mathematics 5877: 5874: 5871: 5868: 5865: 5862: 5831: 5828: 5825: 5817: 5814: 5811: 5808: 5805: 5740:{\displaystyle \mathbf {CGTop} } 5733: 5730: 5727: 5724: 5721: 5699: 5696: 5693: 5678:{\displaystyle \mathbf {CGTop} } 5671: 5668: 5665: 5662: 5659: 5637: 5634: 5631: 5628: 5625: 5622: 5599: 5596: 5593: 5577:{\displaystyle \mathbf {CGTop} } 5570: 5567: 5564: 5561: 5558: 3971:{\displaystyle (X_{i})_{i\in I}} 2981: 956:{\displaystyle T_{\mathcal {F}}} 507:{\displaystyle T_{\mathcal {F}}} 6349:"A note about the Arens' space" 6272:Illinois Journal of Mathematics 5200:{\displaystyle \{K_{\alpha }\}} 4747:{\displaystyle f\circ u:K\to Y} 4642:is continuous for each compact 2933:convenient categories of spaces 1613:{\displaystyle {\mathcal {G}}.} 934:together with the new topology 856:{\displaystyle {\mathcal {F}}.} 472:{\displaystyle {\mathcal {F}},} 6229:Pacific Journal of Mathematics 5914: 5901: 5821: 5706:{\displaystyle \mathbf {Top} } 5606:{\displaystyle \mathbf {Top} } 5230:We define the new topology on 5097: 5085: 4994: 4982: 4877: 4790: 4738: 4626: 4470: 4433: 4421: 4128: 4116: 4096: 4084: 3953: 3939: 3862: 3856: 3754: 3632:{\displaystyle \omega _{1}+1=} 3626: 3607: 3350:of uncountably many copies of 2905:category of topological spaces 2850: 2838: 2818: 2806: 2576:exactly when the intersection 2379: 2310: 2304: 2196: 2078: 2072: 2049: 2043: 1997: 1874: 1755:exactly when the intersection 1532:{\displaystyle {\mathcal {F}}} 1335:exactly when the intersection 1231:{\displaystyle {\mathcal {C}}} 1184:{\displaystyle {\mathcal {F}}} 1060:{\displaystyle {\mathcal {F}}} 1036:{\displaystyle {\mathcal {F}}} 820: 771: 765: 628: 616: 602:{\displaystyle {\mathcal {F}}} 551:{\displaystyle {\mathcal {F}}} 422:{\displaystyle {\mathcal {F}}} 331: 319: 289:category of topological spaces 81:In the simplest definition, a 27:Property of topological spaces 1: 6768:"The category of CGWH spaces" 6591:. Heldermann Verlag, Berlin. 6038:K-space (functional analysis) 4915:{\displaystyle K\subseteq X.} 4664:{\displaystyle K\subseteq X.} 3697:removed is isomorphic to the 3567: 3219:spaces, etc. In particular, 3044:compactly generated Hausdorff 2644:{\displaystyle K\subseteq X.} 1823:{\displaystyle K\subseteq X.} 1285:exactly when its topology is 229:{\displaystyle K\subseteq X.} 111:{\displaystyle A\subseteq X,} 6766:Strickland, Neil P. (2009). 6712:"Compactly generated spaces" 5122:Given any topological space 4439:{\displaystyle k(X\times Y)} 4344:is not compactly generated. 4040:of the compact subspaces of 3809:{\displaystyle U\subseteq X} 3444:{\displaystyle \mathbb {R} } 3394:{\displaystyle \mathbb {Z} } 3365:{\displaystyle \mathbb {R} } 3262:, every compact subspace of 3139:{\displaystyle K\subseteq X} 2549:{\displaystyle A\subseteq X} 2426:of compact Hausdorff spaces. 2257:{\displaystyle A\subseteq X} 1728:{\displaystyle A\subseteq X} 1308:{\displaystyle A\subseteq X} 1019:(with respect to the family 738:{\displaystyle U\subseteq X} 6732:Counterexamples in Topology 5448:is compactly generated. If 5326:{\displaystyle K_{\alpha }} 3690:{\displaystyle \omega _{1}} 3659:{\displaystyle \omega _{1}} 3085:(because given a singleton 1801:for every compact subspace 585:Since all the functions in 534:with respect to the family 207:for every compact subspace 6888: 6822:Compactly generated spaces 6778:Willard, Stephen (2004) . 6347:Ma, Dan (19 August 2010). 5500:Otherwise the topology on 4172:. For example, the space 3710:one-point compactification 3473:one-point compactification 3227:are compactly generated. 3068:Alexandrov-discrete spaces 2602:is open (resp. closed) in 2556:is open (resp. closed) in 2466:one-point compactification 2323:is open (resp. closed) in 2264:is open (resp. closed) in 1781:is open (resp. closed) in 1735:is open (resp. closed) in 1361:is open (resp. closed) in 1315:is open (resp. closed) in 6461:Lawson & Madison 1974 6401:Lawson & Madison 1974 6020:Countably generated space 5356:Denote this new space by 5142:we can define a possibly 4802:{\displaystyle u:K\to X.} 4400:{\displaystyle X\times Y} 4367:locally compact Hausdorff 4337:{\displaystyle X\times Y} 4067:locally compact Hausdorff 3868:{\displaystyle q^{-1}(U)} 3668:first uncountable ordinal 3217:locally compact Hausdorff 3062:are CG-2. This includes 2909:cartesian closed category 2688:{\displaystyle X=\{0,1\}} 2451:locally compact Hausdorff 2449:is a quotient space of a 2422:is a quotient space of a 2391:{\displaystyle f:K\to X.} 2363:and every continuous map 2316:{\displaystyle f^{-1}(A)} 1966:is a quotient space of a 1539:) is to find a subfamily 1462:compactly generated space 777:{\displaystyle f^{-1}(U)} 399:compactly generated space 293:cartesian closed category 83:compactly generated space 59:compactly generated space 6606:Lamartin, W. F. (1977), 6299:Steen & Seebach 1995 6029:Finitely generated space 5920:{\displaystyle k(Y^{X})} 5651:the full subcategory of 5584:the full subcategory of 5349:{\displaystyle \alpha .} 4479:{\displaystyle f:X\to Y} 4109:obtained by identifying 3763:{\displaystyle q:Y\to X} 3314:on an uncountable space. 2944:de Vries duality theorem 2892:, after the German word 2205:{\displaystyle f:K\to X} 2006:{\displaystyle f:K\to X} 1890:from all compact spaces 1883:{\displaystyle f:K\to X} 829:{\displaystyle f:K\to X} 6266:Bankston, Paul (1979). 6180:Hatcher, Allen (2001). 5523:is strictly finer than 4929:For topological spaces 4450:Continuity of functions 4411:. But its k-ification 4358:space is CG-1. (Here, 3538:is an open subspace of 2896:. They were studied by 2595:{\displaystyle A\cap K} 1774:{\displaystyle A\cap K} 1354:{\displaystyle A\cap K} 180:{\displaystyle A\cap K} 6727:Seebach, J. Arthur Jr. 6710:Rezk, Charles (2018). 6681:Upper Saddle River, NJ 6567:Topology and Groupoids 6415:, 5.9.1 (Corollary 2). 6301:, Example 114, p. 136. 6285:10.1215/ijm/1256048236 6241:10.2140/pjm.1980.88.35 5992: 5972: 5948: 5921: 5885: 5842: 5784: 5761: 5741: 5707: 5679: 5645: 5607: 5578: 5537: 5517: 5494: 5462: 5442: 5419: 5399: 5376: 5350: 5327: 5300: 5264: 5250:by declaring a subset 5244: 5224: 5201: 5160: 5136: 5104: 5103:{\displaystyle C(X,Y)} 5065: 5041: 5021: 5001: 5000:{\displaystyle C(X,Y)} 4966: 4943: 4916: 4887: 4845: 4831:is CG-3, the function 4825: 4803: 4768: 4748: 4707: 4693:is CG-2, the function 4687: 4665: 4636: 4591: 4577:is CG-1, the function 4571: 4548: 4528: 4510:, one can express the 4500: 4480: 4440: 4401: 4338: 4308: 4250:from the real line is 4240: 4135: 4103: 4057: 4030: 4014:weakly locally compact 3999: 3972: 3926: 3869: 3830: 3810: 3784: 3764: 3732: 3691: 3660: 3633: 3552: 3532: 3512: 3492: 3465: 3445: 3423: 3395: 3366: 3296: 3276: 3252: 3209:weakly locally compact 3183: 3163: 3140: 3114: 3077:Every CG-3 space is a 3064:first countable spaces 2946:. A definition of the 2860: 2859:{\displaystyle (0,1].} 2825: 2785: 2759: 2733: 2689: 2645: 2616: 2596: 2570: 2550: 2508: 2443: 2416: 2392: 2357: 2337: 2317: 2278: 2258: 2229: 2206: 2170: 2138: 2108: 2085: 2056: 2027: 2007: 1968:weakly locally compact 1960: 1929: 1907: 1884: 1848: 1824: 1795: 1775: 1749: 1729: 1696: 1664: 1614: 1587: 1567: 1533: 1509: 1478: 1454: 1431: 1408: 1375: 1355: 1329: 1309: 1275: 1255: 1232: 1208: 1185: 1159: 1127: 1104: 1081: 1061: 1037: 1005: 983: 957: 928: 908: 885: 857: 830: 798: 778: 739: 713: 682: 658: 638: 637:{\displaystyle (X,T),} 603: 579: 552: 528: 508: 473: 446: 423: 389: 362: 338: 270: 250: 230: 201: 181: 155: 131: 112: 51: 6388:, Proposition 3.4(3). 6015:Compact-open topology 6000:compact-open topology 5993: 5973: 5949: 5947:{\displaystyle Y^{X}} 5922: 5886: 5843: 5785: 5762: 5742: 5708: 5680: 5646: 5608: 5579: 5546:This construction is 5538: 5518: 5495: 5493:{\displaystyle kX=X.} 5463: 5443: 5420: 5400: 5377: 5351: 5328: 5301: 5265: 5245: 5225: 5202: 5174:of the topology. Let 5161: 5137: 5114:equivalence classes. 5105: 5066: 5049:compact-open topology 5042: 5022: 5002: 4967: 4944: 4917: 4888: 4846: 4826: 4804: 4769: 4749: 4708: 4688: 4666: 4637: 4592: 4572: 4549: 4529: 4501: 4481: 4441: 4402: 4339: 4309: 4241: 4136: 4134:{\displaystyle (0,1]} 4104: 4058: 4031: 4000: 3998:{\displaystyle X_{i}} 3973: 3927: 3870: 3831: 3811: 3785: 3765: 3733: 3692: 3661: 3634: 3553: 3533: 3513: 3493: 3466: 3446: 3424: 3396: 3372:(each with the usual 3367: 3297: 3277: 3253: 3225:topological manifolds 3184: 3164: 3141: 3115: 2955:identification spaces 2907:. This fails to be a 2861: 2826: 2786: 2784:{\displaystyle \{1\}} 2760: 2758:{\displaystyle \{0\}} 2734: 2690: 2646: 2617: 2597: 2571: 2551: 2509: 2479:property to form the 2444: 2417: 2393: 2358: 2338: 2318: 2279: 2259: 2230: 2207: 2171: 2139: 2109: 2086: 2057: 2028: 2013:from a compact space 2008: 1961: 1930: 1908: 1885: 1849: 1825: 1796: 1776: 1750: 1730: 1697: 1665: 1615: 1588: 1568: 1534: 1510: 1479: 1455: 1432: 1409: 1376: 1356: 1330: 1310: 1276: 1256: 1233: 1209: 1186: 1160: 1158:{\displaystyle kX=X.} 1128: 1105: 1082: 1062: 1038: 1006: 984: 958: 929: 909: 886: 858: 831: 799: 779: 740: 714: 683: 659: 639: 609:were continuous into 604: 580: 553: 529: 509: 474: 447: 424: 390: 363: 339: 337:{\displaystyle (X,T)} 271: 251: 231: 202: 182: 156: 132: 113: 52: 6427:, Proposition 5.9.1. 5982: 5962: 5931: 5895: 5858: 5801: 5771: 5751: 5717: 5689: 5655: 5618: 5589: 5554: 5527: 5504: 5472: 5452: 5429: 5409: 5386: 5360: 5337: 5310: 5277: 5254: 5234: 5211: 5178: 5150: 5126: 5079: 5055: 5031: 5011: 4976: 4953: 4933: 4897: 4855: 4835: 4815: 4778: 4758: 4720: 4697: 4677: 4646: 4604: 4581: 4561: 4538: 4518: 4490: 4458: 4415: 4385: 4322: 4258: 4176: 4144:More generally, any 4113: 4081: 4044: 4020: 3982: 3936: 3897: 3840: 3820: 3794: 3790:and for an open set 3774: 3742: 3719: 3674: 3643: 3585: 3542: 3522: 3502: 3479: 3455: 3433: 3413: 3383: 3354: 3312:cocountable topology 3286: 3266: 3258:is anticompact and T 3242: 3173: 3150: 3124: 3089: 2980:As explained in the 2835: 2803: 2769: 2743: 2699: 2661: 2626: 2606: 2580: 2560: 2534: 2498: 2494:A topological space 2457:As explained in the 2433: 2406: 2367: 2347: 2327: 2288: 2268: 2242: 2216: 2184: 2160: 2156:(1) The topology on 2128: 2124:A topological space 2095: 2084:{\displaystyle f(K)} 2066: 2055:{\displaystyle f(K)} 2037: 2033:has a compact image 2017: 1985: 1974:As explained in the 1950: 1919: 1894: 1862: 1838: 1834:(2) The topology on 1805: 1785: 1759: 1739: 1713: 1686: 1682:(1) The topology on 1654: 1650:A topological space 1597: 1577: 1543: 1519: 1499: 1468: 1444: 1418: 1385: 1365: 1339: 1319: 1293: 1265: 1242: 1218: 1195: 1171: 1137: 1114: 1091: 1071: 1047: 1023: 995: 967: 938: 918: 895: 875: 840: 808: 788: 749: 723: 700: 672: 648: 613: 589: 566: 538: 518: 489: 456: 433: 409: 376: 352: 316: 260: 240: 211: 191: 165: 145: 121: 93: 76:weak Hausdorff space 41: 6679:(Second ed.). 6535:, Proposition 1.11. 6499:, Proposition 1.11. 5375:{\displaystyle kX.} 5047:topologized by the 4774:and continuous map 4409:categorical product 3816:the restriction of 3046:without ambiguity. 2917:identification maps 2522:if its topology is 2516:compactly-generated 2176:coincides with the 2146:compactly-generated 1854:coincides with the 1672:compactly-generated 1283:compactly generated 1013:compactly generated 982:{\displaystyle kX.} 963:is usually denoted 644:the k-ification of 479:as detailed below. 85:is a space that is 6790:Dover Publications 6723:Steen, Lynn Arthur 6685:Prentice Hall, Inc 6618:Mac Lane, Saunders 6585:Engelking, Ryszard 6487:, Proposition 7.5. 6475:, Proposition 2.6. 6463:, Proposition 1.2. 6439:, Proposition 1.7. 6376:, Proposition 2.2. 6364:, Proposition 1.8. 6256:, Proposition 1.6. 6183:Algebraic Topology 6098:, Definition 43.8. 6083:10.1007/BF02194829 5988: 5968: 5944: 5917: 5881: 5852:exponential object 5838: 5783:{\displaystyle kX} 5780: 5757: 5737: 5703: 5675: 5641: 5603: 5574: 5533: 5516:{\displaystyle kX} 5513: 5490: 5458: 5441:{\displaystyle kX} 5438: 5415: 5398:{\displaystyle kX} 5395: 5372: 5346: 5323: 5296: 5260: 5240: 5223:{\displaystyle X.} 5220: 5197: 5156: 5132: 5110:are precisely the 5100: 5061: 5037: 5017: 4997: 4965:{\displaystyle Y,} 4962: 4939: 4912: 4883: 4841: 4821: 4799: 4764: 4744: 4703: 4683: 4661: 4632: 4587: 4567: 4544: 4524: 4496: 4476: 4436: 4397: 4373:When working in a 4334: 4304: 4236: 4131: 4099: 4056:{\displaystyle X.} 4053: 4026: 3995: 3968: 3922: 3865: 3826: 3806: 3780: 3760: 3731:{\displaystyle X,} 3728: 3687: 3656: 3629: 3558:that is not CG-2. 3548: 3528: 3508: 3491:{\displaystyle Y.} 3488: 3461: 3441: 3419: 3391: 3374:Euclidean topology 3362: 3292: 3272: 3248: 3179: 3162:{\displaystyle K;} 3159: 3136: 3110: 2962:algebraic topology 2948:exponential object 2856: 2821: 2781: 2755: 2729: 2685: 2641: 2612: 2592: 2566: 2546: 2504: 2439: 2412: 2388: 2353: 2333: 2313: 2274: 2254: 2228:{\displaystyle K.} 2225: 2202: 2166: 2134: 2107:{\displaystyle X.} 2104: 2081: 2052: 2023: 2003: 1956: 1943:of compact spaces. 1925: 1906:{\displaystyle K.} 1903: 1880: 1844: 1820: 1791: 1771: 1745: 1725: 1692: 1660: 1610: 1583: 1563: 1529: 1505: 1474: 1450: 1430:{\displaystyle X,} 1427: 1404: 1371: 1351: 1325: 1305: 1271: 1254:{\displaystyle X.} 1251: 1228: 1207:{\displaystyle X,} 1204: 1181: 1155: 1126:{\displaystyle X;} 1123: 1103:{\displaystyle X,} 1100: 1077: 1057: 1033: 1001: 979: 953: 924: 907:{\displaystyle X,} 904: 881: 853: 826: 794: 774: 735: 719:they are the sets 712:{\displaystyle X;} 709: 678: 654: 634: 599: 578:{\displaystyle T.} 575: 548: 524: 504: 469: 445:{\displaystyle X.} 442: 419: 388:{\displaystyle X.} 385: 358: 334: 297:algebraic topology 266: 246: 226: 197: 177: 151: 127: 108: 47: 6799:978-0-486-43479-7 6750:978-0-486-68735-3 6694:978-0-13-181629-9 6673:Munkres, James R. 6547:, Problem 43J(1). 6451:, Example 3.3.29. 6337:, Example 1.6.19. 6313:, Problem 43H(2). 6059:, Definition 1.1. 5991:{\displaystyle Y} 5971:{\displaystyle X} 5796:inclusion functor 5760:{\displaystyle X} 5536:{\displaystyle X} 5461:{\displaystyle X} 5418:{\displaystyle X} 5263:{\displaystyle A} 5243:{\displaystyle X} 5159:{\displaystyle X} 5135:{\displaystyle X} 5064:{\displaystyle X} 5040:{\displaystyle Y} 5020:{\displaystyle X} 4942:{\displaystyle X} 4844:{\displaystyle f} 4824:{\displaystyle X} 4767:{\displaystyle K} 4706:{\displaystyle f} 4686:{\displaystyle X} 4590:{\displaystyle f} 4570:{\displaystyle X} 4547:{\displaystyle f} 4527:{\displaystyle f} 4499:{\displaystyle X} 4316:quotient topology 4248:subspace topology 4029:{\displaystyle X} 3829:{\displaystyle q} 3783:{\displaystyle Y} 3712:, which is CG-1. 3551:{\displaystyle X} 3531:{\displaystyle Y} 3511:{\displaystyle X} 3464:{\displaystyle X} 3422:{\displaystyle Y} 3403:discrete topology 3295:{\displaystyle X} 3275:{\displaystyle X} 3251:{\displaystyle X} 3195:discrete topology 3182:{\displaystyle X} 3060:Sequential spaces 3040: 3039: 2913:cartesian product 2793:discrete topology 2615:{\displaystyle K} 2569:{\displaystyle X} 2507:{\displaystyle X} 2442:{\displaystyle X} 2415:{\displaystyle X} 2356:{\displaystyle K} 2336:{\displaystyle K} 2277:{\displaystyle X} 2169:{\displaystyle X} 2137:{\displaystyle X} 2026:{\displaystyle K} 1959:{\displaystyle X} 1928:{\displaystyle X} 1847:{\displaystyle X} 1794:{\displaystyle K} 1748:{\displaystyle X} 1695:{\displaystyle X} 1663:{\displaystyle X} 1586:{\displaystyle X} 1508:{\displaystyle X} 1477:{\displaystyle X} 1453:{\displaystyle X} 1374:{\displaystyle K} 1328:{\displaystyle X} 1274:{\displaystyle X} 1080:{\displaystyle X} 1004:{\displaystyle X} 927:{\displaystyle X} 884:{\displaystyle X} 797:{\displaystyle K} 681:{\displaystyle T} 657:{\displaystyle T} 527:{\displaystyle X} 361:{\displaystyle T} 346:topological space 269:{\displaystyle X} 249:{\displaystyle X} 200:{\displaystyle K} 154:{\displaystyle X} 130:{\displaystyle A} 50:{\displaystyle X} 36:topological space 16:(Redirected from 6879: 6867:General topology 6811: 6781:General Topology 6774: 6772: 6762: 6718: 6716: 6706: 6668: 6656: 6641: 6613: 6602: 6589:General Topology 6580: 6548: 6542: 6536: 6530: 6524: 6523:, Theorem 43.10. 6518: 6512: 6506: 6500: 6494: 6488: 6482: 6476: 6470: 6464: 6458: 6452: 6446: 6440: 6434: 6428: 6422: 6416: 6410: 6404: 6398: 6389: 6383: 6377: 6371: 6365: 6359: 6353: 6352: 6344: 6338: 6332: 6326: 6320: 6314: 6308: 6302: 6296: 6290: 6289: 6287: 6263: 6257: 6251: 6245: 6244: 6226: 6217: 6211: 6205: 6196: 6193:See the Appendix 6190: 6188: 6177: 6171: 6165: 6156: 6144: 6138: 6132: 6126: 6120: 6111: 6105: 6099: 6093: 6087: 6086: 6066: 6060: 6054: 6034: 6025: 5997: 5995: 5994: 5989: 5977: 5975: 5974: 5969: 5954:is the space of 5953: 5951: 5950: 5945: 5943: 5942: 5926: 5924: 5923: 5918: 5913: 5912: 5890: 5888: 5887: 5882: 5880: 5847: 5845: 5844: 5839: 5834: 5820: 5789: 5787: 5786: 5781: 5766: 5764: 5763: 5758: 5746: 5744: 5743: 5738: 5736: 5712: 5710: 5709: 5704: 5702: 5684: 5682: 5681: 5676: 5674: 5650: 5648: 5647: 5642: 5640: 5612: 5610: 5609: 5604: 5602: 5583: 5581: 5580: 5575: 5573: 5542: 5540: 5539: 5534: 5522: 5520: 5519: 5514: 5499: 5497: 5496: 5491: 5467: 5465: 5464: 5459: 5447: 5445: 5444: 5439: 5424: 5422: 5421: 5416: 5404: 5402: 5401: 5396: 5381: 5379: 5378: 5373: 5355: 5353: 5352: 5347: 5332: 5330: 5329: 5324: 5322: 5321: 5305: 5303: 5302: 5297: 5295: 5294: 5269: 5267: 5266: 5261: 5249: 5247: 5246: 5241: 5229: 5227: 5226: 5221: 5206: 5204: 5203: 5198: 5193: 5192: 5172: 5171: 5165: 5163: 5162: 5157: 5141: 5139: 5138: 5133: 5109: 5107: 5106: 5101: 5070: 5068: 5067: 5062: 5046: 5044: 5043: 5038: 5026: 5024: 5023: 5018: 5006: 5004: 5003: 4998: 4971: 4969: 4968: 4963: 4948: 4946: 4945: 4940: 4921: 4919: 4918: 4913: 4892: 4890: 4889: 4884: 4870: 4869: 4850: 4848: 4847: 4842: 4830: 4828: 4827: 4822: 4808: 4806: 4805: 4800: 4773: 4771: 4770: 4765: 4753: 4751: 4750: 4745: 4712: 4710: 4709: 4704: 4692: 4690: 4689: 4684: 4670: 4668: 4667: 4662: 4641: 4639: 4638: 4633: 4619: 4618: 4596: 4594: 4593: 4588: 4576: 4574: 4573: 4568: 4553: 4551: 4550: 4545: 4533: 4531: 4530: 4525: 4505: 4503: 4502: 4497: 4485: 4483: 4482: 4477: 4445: 4443: 4442: 4437: 4406: 4404: 4403: 4398: 4379:product topology 4343: 4341: 4340: 4335: 4313: 4311: 4310: 4305: 4276: 4271: 4245: 4243: 4242: 4237: 4223: 4209: 4189: 4140: 4138: 4137: 4132: 4108: 4106: 4105: 4102:{\displaystyle } 4100: 4075:Sierpiński space 4062: 4060: 4059: 4054: 4035: 4033: 4032: 4027: 4004: 4002: 4001: 3996: 3994: 3993: 3977: 3975: 3974: 3969: 3967: 3966: 3951: 3950: 3931: 3929: 3928: 3923: 3921: 3920: 3911: 3910: 3905: 3874: 3872: 3871: 3866: 3855: 3854: 3835: 3833: 3832: 3827: 3815: 3813: 3812: 3807: 3789: 3787: 3786: 3781: 3769: 3767: 3766: 3761: 3737: 3735: 3734: 3729: 3715:In a CG-2 space 3703:Arens-Fort space 3699:Fortissimo space 3696: 3694: 3693: 3688: 3686: 3685: 3665: 3663: 3662: 3657: 3655: 3654: 3638: 3636: 3635: 3630: 3625: 3624: 3597: 3596: 3557: 3555: 3554: 3549: 3537: 3535: 3534: 3529: 3517: 3515: 3514: 3509: 3497: 3495: 3494: 3489: 3470: 3468: 3467: 3462: 3450: 3448: 3447: 3442: 3440: 3428: 3426: 3425: 3420: 3400: 3398: 3397: 3392: 3390: 3371: 3369: 3368: 3363: 3361: 3326:Arens-Fort space 3319:Fortissimo space 3301: 3299: 3298: 3293: 3281: 3279: 3278: 3273: 3257: 3255: 3254: 3249: 3199:Sierpiński space 3193:spaces have the 3188: 3186: 3185: 3180: 3168: 3166: 3165: 3160: 3145: 3143: 3142: 3137: 3119: 3117: 3116: 3111: 3006:Meaning summary 3000: 2940:full subcategory 2865: 2863: 2862: 2857: 2830: 2828: 2827: 2824:{\displaystyle } 2822: 2790: 2788: 2787: 2782: 2764: 2762: 2761: 2756: 2738: 2736: 2735: 2730: 2694: 2692: 2691: 2686: 2656:Sierpiński space 2650: 2648: 2647: 2642: 2621: 2619: 2618: 2613: 2601: 2599: 2598: 2593: 2575: 2573: 2572: 2567: 2555: 2553: 2552: 2547: 2513: 2511: 2510: 2505: 2470:Arens-Fort space 2448: 2446: 2445: 2440: 2421: 2419: 2418: 2413: 2397: 2395: 2394: 2389: 2362: 2360: 2359: 2354: 2342: 2340: 2339: 2334: 2322: 2320: 2319: 2314: 2303: 2302: 2283: 2281: 2280: 2275: 2263: 2261: 2260: 2255: 2234: 2232: 2231: 2226: 2211: 2209: 2208: 2203: 2175: 2173: 2172: 2167: 2143: 2141: 2140: 2135: 2113: 2111: 2110: 2105: 2090: 2088: 2087: 2082: 2061: 2059: 2058: 2053: 2032: 2030: 2029: 2024: 2012: 2010: 2009: 2004: 1965: 1963: 1962: 1957: 1934: 1932: 1931: 1926: 1912: 1910: 1909: 1904: 1889: 1887: 1886: 1881: 1853: 1851: 1850: 1845: 1829: 1827: 1826: 1821: 1800: 1798: 1797: 1792: 1780: 1778: 1777: 1772: 1754: 1752: 1751: 1746: 1734: 1732: 1731: 1726: 1701: 1699: 1698: 1693: 1669: 1667: 1666: 1661: 1633: 1632: 1619: 1617: 1616: 1611: 1606: 1605: 1592: 1590: 1589: 1584: 1572: 1570: 1569: 1564: 1562: 1561: 1552: 1551: 1538: 1536: 1535: 1530: 1528: 1527: 1514: 1512: 1511: 1506: 1483: 1481: 1480: 1475: 1459: 1457: 1456: 1451: 1436: 1434: 1433: 1428: 1413: 1411: 1410: 1405: 1400: 1399: 1380: 1378: 1377: 1372: 1360: 1358: 1357: 1352: 1334: 1332: 1331: 1326: 1314: 1312: 1311: 1306: 1280: 1278: 1277: 1272: 1260: 1258: 1257: 1252: 1238:of subspaces of 1237: 1235: 1234: 1229: 1227: 1226: 1213: 1211: 1210: 1205: 1190: 1188: 1187: 1182: 1180: 1179: 1164: 1162: 1161: 1156: 1133:or in short, if 1132: 1130: 1129: 1124: 1109: 1107: 1106: 1101: 1086: 1084: 1083: 1078: 1066: 1064: 1063: 1058: 1056: 1055: 1042: 1040: 1039: 1034: 1032: 1031: 1010: 1008: 1007: 1002: 988: 986: 985: 980: 962: 960: 959: 954: 952: 951: 950: 933: 931: 930: 925: 913: 911: 910: 905: 890: 888: 887: 882: 869: 868: 862: 860: 859: 854: 849: 848: 835: 833: 832: 827: 803: 801: 800: 795: 783: 781: 780: 775: 764: 763: 744: 742: 741: 736: 718: 716: 715: 710: 694: 693: 687: 685: 684: 679: 663: 661: 660: 655: 643: 641: 640: 635: 608: 606: 605: 600: 598: 597: 584: 582: 581: 576: 557: 555: 554: 549: 547: 546: 533: 531: 530: 525: 513: 511: 510: 505: 503: 502: 501: 478: 476: 475: 470: 465: 464: 451: 449: 448: 443: 428: 426: 425: 420: 418: 417: 394: 392: 391: 386: 367: 365: 364: 359: 343: 341: 340: 335: 282:Hausdorff spaces 275: 273: 272: 267: 255: 253: 252: 247: 235: 233: 232: 227: 206: 204: 203: 198: 186: 184: 183: 178: 160: 158: 157: 152: 136: 134: 133: 128: 117: 115: 114: 109: 56: 54: 53: 48: 21: 6887: 6886: 6882: 6881: 6880: 6878: 6877: 6876: 6872:Homotopy theory 6857: 6856: 6818: 6816:Further reading 6800: 6777: 6770: 6765: 6751: 6741:Springer-Verlag 6721: 6714: 6709: 6695: 6671: 6665: 6654: 6644: 6638: 6616: 6605: 6599: 6583: 6578: 6560: 6557: 6552: 6551: 6543: 6539: 6533:Strickland 2009 6531: 6527: 6519: 6515: 6507: 6503: 6495: 6491: 6483: 6479: 6473:Strickland 2009 6471: 6467: 6459: 6455: 6447: 6443: 6435: 6431: 6423: 6419: 6411: 6407: 6399: 6392: 6384: 6380: 6374:Strickland 2009 6372: 6368: 6360: 6356: 6346: 6345: 6341: 6333: 6329: 6321: 6317: 6309: 6305: 6297: 6293: 6265: 6264: 6260: 6254:Strickland 2009 6252: 6248: 6224: 6219: 6218: 6214: 6206: 6199: 6186: 6179: 6178: 6174: 6170:, Lemma 1.4(c). 6168:Strickland 2009 6166: 6159: 6145: 6141: 6135:Strickland 2009 6133: 6129: 6121: 6114: 6106: 6102: 6094: 6090: 6071:Semigroup Forum 6068: 6067: 6063: 6057:Strickland 2009 6055: 6051: 6046: 6032: 6023: 6011: 5980: 5979: 5960: 5959: 5956:continuous maps 5934: 5929: 5928: 5904: 5893: 5892: 5856: 5855: 5799: 5798: 5769: 5768: 5749: 5748: 5715: 5714: 5687: 5686: 5653: 5652: 5616: 5615: 5587: 5586: 5552: 5551: 5525: 5524: 5502: 5501: 5470: 5469: 5450: 5449: 5427: 5426: 5407: 5406: 5384: 5383: 5358: 5357: 5335: 5334: 5333:for each index 5313: 5308: 5307: 5286: 5275: 5274: 5252: 5251: 5232: 5231: 5209: 5208: 5184: 5176: 5175: 5169: 5168: 5148: 5147: 5124: 5123: 5120: 5077: 5076: 5073:path components 5053: 5052: 5029: 5028: 5009: 5008: 4974: 4973: 4951: 4950: 4931: 4930: 4927: 4895: 4894: 4861: 4853: 4852: 4833: 4832: 4813: 4812: 4776: 4775: 4756: 4755: 4718: 4717: 4695: 4694: 4675: 4674: 4644: 4643: 4610: 4602: 4601: 4579: 4578: 4559: 4558: 4536: 4535: 4516: 4515: 4488: 4487: 4456: 4455: 4452: 4413: 4412: 4383: 4382: 4360:locally compact 4356:locally compact 4320: 4319: 4256: 4255: 4252:first countable 4174: 4173: 4162: 4111: 4110: 4079: 4078: 4042: 4041: 4018: 4017: 3985: 3980: 3979: 3952: 3942: 3934: 3933: 3912: 3900: 3895: 3894: 3888: 3843: 3838: 3837: 3818: 3817: 3792: 3791: 3772: 3771: 3740: 3739: 3717: 3716: 3677: 3672: 3671: 3646: 3641: 3640: 3616: 3588: 3583: 3582: 3576: 3564: 3540: 3539: 3520: 3519: 3500: 3499: 3477: 3476: 3453: 3452: 3431: 3430: 3411: 3410: 3401:(each with the 3381: 3380: 3352: 3351: 3305: 3284: 3283: 3264: 3263: 3261: 3240: 3239: 3192: 3171: 3170: 3148: 3147: 3122: 3121: 3087: 3086: 3082: 2978: 2886: 2833: 2832: 2801: 2800: 2767: 2766: 2741: 2740: 2697: 2696: 2659: 2658: 2624: 2623: 2604: 2603: 2578: 2577: 2558: 2557: 2532: 2531: 2496: 2495: 2489: 2431: 2430: 2424:topological sum 2404: 2403: 2365: 2364: 2345: 2344: 2325: 2324: 2291: 2286: 2285: 2266: 2265: 2240: 2239: 2214: 2213: 2182: 2181: 2158: 2157: 2126: 2125: 2119: 2093: 2092: 2064: 2063: 2035: 2034: 2015: 2014: 1983: 1982: 1948: 1947: 1941:topological sum 1917: 1916: 1892: 1891: 1860: 1859: 1836: 1835: 1803: 1802: 1783: 1782: 1757: 1756: 1737: 1736: 1711: 1710: 1684: 1683: 1652: 1651: 1645: 1630: 1629: 1595: 1594: 1575: 1574: 1541: 1540: 1517: 1516: 1497: 1496: 1466: 1465: 1442: 1441: 1416: 1415: 1383: 1382: 1363: 1362: 1337: 1336: 1317: 1316: 1291: 1290: 1263: 1262: 1240: 1239: 1216: 1215: 1193: 1192: 1169: 1168: 1135: 1134: 1112: 1111: 1089: 1088: 1069: 1068: 1045: 1044: 1021: 1020: 993: 992: 965: 964: 941: 936: 935: 916: 915: 893: 892: 873: 872: 866: 865: 863:Similarly, the 838: 837: 806: 805: 786: 785: 752: 747: 746: 721: 720: 698: 697: 691: 690: 670: 669: 646: 645: 611: 610: 587: 586: 564: 563: 536: 535: 516: 515: 492: 487: 486: 454: 453: 431: 430: 407: 406: 374: 373: 350: 349: 314: 313: 310: 305: 258: 257: 238: 237: 209: 208: 189: 188: 163: 162: 161:if and only if 143: 142: 119: 118: 91: 90: 72:Hausdorff space 39: 38: 28: 23: 22: 15: 12: 11: 5: 6885: 6883: 6875: 6874: 6869: 6859: 6858: 6855: 6854: 6849: 6837: 6825: 6817: 6814: 6813: 6812: 6798: 6775: 6763: 6749: 6719: 6707: 6693: 6669: 6663: 6642: 6636: 6614: 6603: 6597: 6581: 6576: 6556: 6553: 6550: 6549: 6537: 6525: 6513: 6511:, section 3.5. 6501: 6489: 6477: 6465: 6453: 6449:Engelking 1989 6441: 6429: 6417: 6405: 6390: 6378: 6366: 6354: 6339: 6335:Engelking 1989 6327: 6315: 6303: 6291: 6278:(2): 241–252. 6258: 6246: 6212: 6210:, section 5.9. 6197: 6172: 6157: 6139: 6127: 6125:, p. 182. 6112: 6110:, p. 283. 6100: 6088: 6061: 6048: 6047: 6045: 6042: 6041: 6040: 6035: 6026: 6017: 6010: 6007: 5987: 5967: 5941: 5937: 5916: 5911: 5907: 5903: 5900: 5879: 5876: 5873: 5870: 5867: 5864: 5837: 5833: 5830: 5827: 5823: 5819: 5816: 5813: 5810: 5807: 5779: 5776: 5756: 5735: 5732: 5729: 5726: 5723: 5701: 5698: 5695: 5673: 5670: 5667: 5664: 5661: 5639: 5636: 5633: 5630: 5627: 5624: 5601: 5598: 5595: 5572: 5569: 5566: 5563: 5560: 5532: 5512: 5509: 5489: 5486: 5483: 5480: 5477: 5457: 5437: 5434: 5414: 5394: 5391: 5371: 5368: 5365: 5345: 5342: 5320: 5316: 5293: 5289: 5285: 5282: 5272:if and only if 5259: 5239: 5219: 5216: 5196: 5191: 5187: 5183: 5155: 5144:finer topology 5131: 5119: 5116: 5099: 5096: 5093: 5090: 5087: 5084: 5060: 5036: 5016: 4996: 4993: 4990: 4987: 4984: 4981: 4961: 4958: 4938: 4926: 4923: 4911: 4908: 4905: 4902: 4882: 4879: 4876: 4873: 4868: 4864: 4860: 4840: 4820: 4798: 4795: 4792: 4789: 4786: 4783: 4763: 4743: 4740: 4737: 4734: 4731: 4728: 4725: 4702: 4682: 4660: 4657: 4654: 4651: 4631: 4628: 4625: 4622: 4617: 4613: 4609: 4586: 4566: 4543: 4523: 4508:final topology 4495: 4475: 4472: 4469: 4466: 4463: 4451: 4448: 4435: 4432: 4429: 4426: 4423: 4420: 4396: 4393: 4390: 4371: 4370: 4369:space is CG-2. 4363: 4352: 4333: 4330: 4327: 4303: 4300: 4297: 4294: 4291: 4288: 4285: 4282: 4279: 4275: 4270: 4266: 4263: 4235: 4232: 4229: 4226: 4222: 4218: 4215: 4212: 4208: 4204: 4201: 4198: 4195: 4192: 4188: 4184: 4181: 4161: 4158: 4146:final topology 4130: 4127: 4124: 4121: 4118: 4098: 4095: 4092: 4089: 4086: 4052: 4049: 4038:disjoint union 4025: 4010:quotient space 3992: 3988: 3965: 3962: 3959: 3955: 3949: 3945: 3941: 3919: 3915: 3909: 3904: 3892:disjoint union 3887: 3884: 3877:locally closed 3864: 3861: 3858: 3853: 3850: 3846: 3825: 3805: 3802: 3799: 3779: 3759: 3756: 3753: 3750: 3747: 3727: 3724: 3684: 3680: 3653: 3649: 3628: 3623: 3619: 3615: 3612: 3609: 3606: 3603: 3600: 3595: 3591: 3575: 3572: 3563: 3560: 3547: 3527: 3507: 3487: 3484: 3460: 3439: 3418: 3407: 3406: 3389: 3377: 3360: 3340: 3339: 3336: 3329: 3322: 3315: 3303: 3291: 3271: 3259: 3247: 3205:Compact spaces 3190: 3178: 3158: 3155: 3135: 3132: 3129: 3109: 3106: 3103: 3100: 3097: 3094: 3080: 3054:weak Hausdorff 3038: 3037: 3034: 3028: 3027: 3024: 3018: 3017: 3014: 3008: 3007: 3004: 2977: 2974: 2966:weak Hausdorff 2960:In modern-day 2885: 2882: 2874:weak Hausdorff 2855: 2852: 2849: 2846: 2843: 2840: 2820: 2817: 2814: 2811: 2808: 2780: 2777: 2774: 2754: 2751: 2748: 2728: 2725: 2722: 2719: 2716: 2713: 2710: 2707: 2704: 2695:with topology 2684: 2681: 2678: 2675: 2672: 2669: 2666: 2652: 2651: 2640: 2637: 2634: 2631: 2611: 2591: 2588: 2585: 2565: 2545: 2542: 2539: 2503: 2488: 2485: 2477:weak Hausdorff 2459:final topology 2455: 2454: 2438: 2427: 2411: 2400: 2399: 2398: 2387: 2384: 2381: 2378: 2375: 2372: 2352: 2332: 2312: 2309: 2306: 2301: 2298: 2294: 2273: 2253: 2250: 2247: 2224: 2221: 2201: 2198: 2195: 2192: 2189: 2178:final topology 2165: 2133: 2118: 2115: 2103: 2100: 2080: 2077: 2074: 2071: 2051: 2048: 2045: 2042: 2022: 2002: 1999: 1996: 1993: 1990: 1976:final topology 1972: 1971: 1955: 1944: 1937:quotient space 1924: 1913: 1902: 1899: 1879: 1876: 1873: 1870: 1867: 1856:final topology 1843: 1832: 1831: 1830: 1819: 1816: 1813: 1810: 1790: 1770: 1767: 1764: 1744: 1724: 1721: 1718: 1691: 1659: 1644: 1641: 1609: 1604: 1582: 1560: 1555: 1550: 1526: 1504: 1490:weak Hausdorff 1473: 1449: 1426: 1423: 1403: 1398: 1393: 1390: 1370: 1350: 1347: 1344: 1324: 1304: 1301: 1298: 1270: 1250: 1247: 1225: 1203: 1200: 1178: 1154: 1151: 1148: 1145: 1142: 1122: 1119: 1099: 1096: 1076: 1054: 1030: 1000: 978: 975: 972: 949: 944: 923: 903: 900: 880: 852: 847: 825: 822: 819: 816: 813: 793: 773: 770: 767: 762: 759: 755: 734: 731: 728: 708: 705: 677: 653: 633: 630: 627: 624: 621: 618: 596: 574: 571: 558:is called the 545: 523: 500: 495: 484:final topology 468: 463: 441: 438: 416: 384: 381: 357: 333: 330: 327: 324: 321: 309: 306: 304: 301: 278:final topology 265: 245: 225: 222: 219: 216: 196: 176: 173: 170: 150: 126: 107: 104: 101: 98: 67:compact spaces 46: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 6884: 6873: 6870: 6868: 6865: 6864: 6862: 6853: 6850: 6848: 6846: 6841: 6838: 6836: 6834: 6829: 6826: 6823: 6820: 6819: 6815: 6809: 6805: 6801: 6795: 6791: 6787: 6786:Mineola, N.Y. 6783: 6782: 6776: 6769: 6764: 6760: 6756: 6752: 6746: 6742: 6738: 6734: 6733: 6728: 6724: 6720: 6713: 6708: 6704: 6700: 6696: 6690: 6686: 6682: 6678: 6674: 6670: 6666: 6664:0-226-51183-9 6660: 6653: 6652: 6647: 6646:May, J. Peter 6643: 6639: 6637:0-387-98403-8 6633: 6629: 6625: 6624: 6619: 6615: 6611: 6610: 6604: 6600: 6598:3-88538-006-4 6594: 6590: 6586: 6582: 6579: 6577:1-4196-2722-8 6573: 6570:, Booksurge, 6569: 6568: 6563: 6562:Brown, Ronald 6559: 6558: 6554: 6546: 6541: 6538: 6534: 6529: 6526: 6522: 6517: 6514: 6510: 6505: 6502: 6498: 6497:Lamartin 1977 6493: 6490: 6486: 6481: 6478: 6474: 6469: 6466: 6462: 6457: 6454: 6450: 6445: 6442: 6438: 6437:Lamartin 1977 6433: 6430: 6426: 6421: 6418: 6414: 6409: 6406: 6402: 6397: 6395: 6391: 6387: 6382: 6379: 6375: 6370: 6367: 6363: 6362:Lamartin 1977 6358: 6355: 6350: 6343: 6340: 6336: 6331: 6328: 6324: 6323:Lamartin 1977 6319: 6316: 6312: 6307: 6304: 6300: 6295: 6292: 6286: 6281: 6277: 6273: 6269: 6262: 6259: 6255: 6250: 6247: 6242: 6238: 6234: 6230: 6223: 6216: 6213: 6209: 6204: 6202: 6198: 6194: 6185: 6184: 6176: 6173: 6169: 6164: 6162: 6158: 6155: 6153: 6148: 6143: 6140: 6136: 6131: 6128: 6124: 6119: 6117: 6113: 6109: 6104: 6101: 6097: 6092: 6089: 6084: 6080: 6076: 6072: 6065: 6062: 6058: 6053: 6050: 6043: 6039: 6036: 6030: 6027: 6021: 6018: 6016: 6013: 6012: 6008: 6006: 6003: 6001: 5985: 5965: 5957: 5939: 5935: 5909: 5905: 5898: 5853: 5848: 5835: 5797: 5793: 5792:right adjoint 5777: 5774: 5754: 5613: 5550:. We denote 5549: 5544: 5530: 5510: 5507: 5487: 5484: 5481: 5478: 5475: 5455: 5435: 5432: 5412: 5392: 5389: 5369: 5366: 5363: 5343: 5340: 5318: 5314: 5306:is closed in 5291: 5287: 5283: 5280: 5273: 5270:to be closed 5257: 5237: 5217: 5214: 5189: 5185: 5173: 5153: 5145: 5129: 5117: 5115: 5113: 5094: 5091: 5088: 5082: 5074: 5071:is CG-1, the 5058: 5050: 5034: 5014: 4991: 4988: 4985: 4979: 4959: 4956: 4936: 4925:Miscellaneous 4924: 4922: 4909: 4906: 4903: 4900: 4880: 4874: 4871: 4866: 4858: 4838: 4818: 4809: 4796: 4793: 4787: 4784: 4781: 4761: 4741: 4735: 4732: 4729: 4726: 4723: 4716: 4700: 4680: 4671: 4658: 4655: 4652: 4649: 4629: 4623: 4620: 4615: 4607: 4600: 4584: 4564: 4555: 4541: 4521: 4513: 4509: 4493: 4473: 4467: 4464: 4461: 4449: 4447: 4430: 4427: 4424: 4418: 4410: 4394: 4391: 4388: 4380: 4376: 4368: 4364: 4361: 4357: 4353: 4350: 4349: 4348: 4345: 4331: 4328: 4325: 4317: 4298: 4295: 4292: 4289: 4286: 4283: 4280: 4273: 4264: 4261: 4253: 4249: 4230: 4227: 4224: 4220: 4216: 4213: 4210: 4206: 4202: 4199: 4196: 4182: 4179: 4171: 4167: 4159: 4157: 4155: 4150: 4147: 4142: 4125: 4122: 4119: 4093: 4090: 4087: 4076: 4070: 4068: 4063: 4050: 4047: 4039: 4023: 4015: 4011: 4006: 3990: 3986: 3963: 3960: 3957: 3947: 3943: 3917: 3913: 3907: 3902: 3893: 3885: 3883: 3880: 3878: 3859: 3851: 3848: 3844: 3823: 3803: 3800: 3797: 3777: 3757: 3751: 3748: 3745: 3725: 3722: 3713: 3711: 3706: 3704: 3700: 3682: 3678: 3669: 3651: 3647: 3621: 3617: 3613: 3610: 3604: 3601: 3598: 3593: 3589: 3581: 3580:ordinal space 3573: 3571: 3569: 3561: 3559: 3545: 3525: 3505: 3485: 3482: 3474: 3458: 3416: 3404: 3378: 3375: 3349: 3345: 3344: 3343: 3337: 3334: 3330: 3327: 3323: 3320: 3316: 3313: 3309: 3308: 3307: 3289: 3269: 3245: 3237: 3232: 3230: 3226: 3222: 3221:metric spaces 3218: 3212: 3210: 3206: 3202: 3200: 3196: 3176: 3156: 3153: 3133: 3130: 3127: 3107: 3104: 3101: 3095: 3084: 3075: 3073: 3072:finite spaces 3069: 3065: 3061: 3057: 3055: 3050: 3047: 3045: 3035: 3033: 3030: 3029: 3025: 3023: 3020: 3019: 3015: 3013: 3010: 3009: 3005: 3002: 3001: 2998: 2996: 2992: 2988: 2983: 2975: 2973: 2971: 2967: 2963: 2958: 2956: 2951: 2949: 2945: 2941: 2936: 2934: 2930: 2928: 2922: 2918: 2914: 2910: 2906: 2901: 2899: 2895: 2891: 2883: 2881: 2879: 2875: 2872:However, for 2870: 2866: 2853: 2847: 2844: 2841: 2815: 2812: 2809: 2798: 2794: 2775: 2749: 2723: 2720: 2714: 2708: 2679: 2676: 2673: 2667: 2664: 2657: 2638: 2635: 2632: 2629: 2609: 2589: 2586: 2583: 2563: 2543: 2540: 2537: 2529: 2528: 2527: 2525: 2521: 2517: 2501: 2492: 2486: 2484: 2482: 2478: 2473: 2471: 2467: 2462: 2460: 2452: 2436: 2428: 2425: 2409: 2401: 2385: 2382: 2376: 2373: 2370: 2350: 2330: 2307: 2299: 2296: 2292: 2284:exactly when 2271: 2251: 2248: 2245: 2237: 2236: 2222: 2219: 2199: 2193: 2190: 2187: 2179: 2163: 2155: 2154: 2153: 2151: 2147: 2131: 2122: 2117:Definition 2 2116: 2114: 2101: 2098: 2075: 2069: 2046: 2040: 2020: 2000: 1994: 1991: 1988: 1979: 1977: 1969: 1953: 1945: 1942: 1938: 1922: 1914: 1900: 1897: 1877: 1871: 1868: 1865: 1857: 1841: 1833: 1817: 1814: 1811: 1808: 1788: 1768: 1765: 1762: 1742: 1722: 1719: 1716: 1708: 1707: 1705: 1689: 1681: 1680: 1679: 1677: 1673: 1657: 1648: 1642: 1640: 1638: 1634: 1625: 1622: 1607: 1580: 1553: 1502: 1493: 1491: 1487: 1471: 1463: 1447: 1438: 1424: 1421: 1401: 1391: 1388: 1368: 1348: 1345: 1342: 1322: 1302: 1299: 1296: 1288: 1284: 1268: 1248: 1245: 1201: 1198: 1165: 1152: 1149: 1146: 1143: 1140: 1120: 1117: 1097: 1094: 1074: 1018: 1014: 998: 989: 976: 973: 970: 942: 921: 901: 898: 878: 870: 867:k-closed sets 850: 823: 817: 814: 811: 791: 768: 760: 757: 753: 732: 729: 726: 706: 703: 695: 675: 667: 651: 631: 625: 622: 619: 572: 569: 561: 521: 493: 485: 480: 466: 439: 436: 404: 400: 395: 382: 379: 371: 355: 347: 328: 325: 322: 307: 302: 300: 298: 294: 290: 285: 283: 279: 263: 243: 223: 220: 217: 214: 194: 174: 171: 168: 148: 140: 124: 105: 102: 99: 96: 88: 84: 79: 77: 73: 68: 64: 60: 44: 37: 33: 19: 6844: 6832: 6780: 6730: 6676: 6650: 6627: 6621: 6608: 6588: 6566: 6545:Willard 2004 6540: 6528: 6521:Willard 2004 6516: 6504: 6492: 6480: 6468: 6456: 6444: 6432: 6420: 6408: 6403:, p. 3. 6381: 6369: 6357: 6342: 6330: 6325:, p. 8. 6318: 6311:Willard 2004 6306: 6294: 6275: 6271: 6261: 6249: 6235:(1): 35–53. 6232: 6228: 6215: 6192: 6182: 6175: 6151: 6142: 6130: 6108:Munkres 2000 6103: 6096:Willard 2004 6091: 6074: 6070: 6064: 6052: 6004: 5891:is given by 5849: 5545: 5167: 5121: 4928: 4810: 4672: 4556: 4453: 4372: 4359: 4346: 4254:; the space 4163: 4151: 4143: 4141:to a point. 4071: 4064: 4007: 3932:of a family 3889: 3881: 3714: 3707: 3577: 3565: 3408: 3341: 3333:Appert space 3235: 3233: 3229:CW complexes 3213: 3203: 3189:). Finite T 3076: 3058: 3051: 3048: 3043: 3041: 3003:Abbreviation 2994: 2990: 2986: 2979: 2959: 2952: 2937: 2926: 2921:CW-complexes 2911:, the usual 2902: 2893: 2889: 2887: 2871: 2867: 2797:homeomorphic 2653: 2519: 2515: 2493: 2490: 2487:Definition 3 2474: 2463: 2456: 2149: 2145: 2123: 2120: 1980: 1973: 1675: 1671: 1649: 1646: 1643:Definition 1 1628: 1626: 1623: 1494: 1461: 1439: 1282: 1166: 1016: 1012: 990: 864: 689: 559: 481: 402: 398: 396: 311: 286: 256:and declare 82: 80: 62: 58: 57:is called a 29: 5747:that takes 5170:k-ification 5118:K-ification 4715:composition 4599:restriction 3236:anticompact 2982:Definitions 784:is open in 692:k-open sets 560:k-ification 303:Definitions 187:is open in 6861:Categories 6555:References 6425:Brown 2006 6413:Brown 2006 6208:Brown 2006 6123:Brown 2006 5548:functorial 4512:continuity 4170:sequential 3562:Properties 3498:The space 3451:) and let 2884:Motivation 2514:is called 2144:is called 1670:is called 1573:such that 1381:for every 1261:The space 1011:is called 991:The space 804:for every 745:such that 6729:(1995) . 6509:Rezk 2018 6485:Rezk 2018 6386:Rezk 2018 5998:with the 5822:→ 5341:α 5319:α 5292:α 5284:∩ 5190:α 4904:⊆ 4878:→ 4791:→ 4739:→ 4727:∘ 4653:⊆ 4627:→ 4471:→ 4428:× 4392:× 4329:× 4314:with the 4299:… 4246:with the 4231:… 4191:∖ 4154:wedge sum 3961:∈ 3903:∐ 3886:Quotients 3849:− 3801:⊆ 3755:→ 3679:ω 3648:ω 3618:ω 3590:ω 3574:Subspaces 3566:(See the 3131:⊆ 3102:⊆ 2706:∅ 2633:⊆ 2587:∩ 2541:⊆ 2380:→ 2297:− 2249:⊆ 2197:→ 1998:→ 1875:→ 1812:⊆ 1766:∩ 1720:⊆ 1637:Hausdorff 1554:⊆ 1486:Hausdorff 1392:∈ 1346:∩ 1300:⊆ 821:→ 758:− 730:⊆ 218:⊆ 172:∩ 100:⊆ 6703:42683260 6677:Topology 6675:(2000). 6648:(1999). 6620:(1998). 6587:(1989). 6564:(2006), 6077:: 1–18. 6009:See also 5112:homotopy 4375:category 4160:Products 3568:Examples 2976:Examples 2898:Hurewicz 2890:k-spaces 2524:coherent 1704:coherent 1287:coherent 1281:is then 370:topology 348:, where 87:coherent 32:topology 6842:at the 6830:at the 6759:0507446 6149:at the 5794:to the 4166:product 3666:is the 3471:be the 3348:product 2894:kompakt 2520:k-space 2468:of the 2150:k-space 1676:k-space 1017:k-space 403:k-space 368:is the 63:k-space 6808:115240 6806:  6796:  6757:  6747:  6701:  6691:  6661:  6634:  6595:  6574:  5927:where 5051:. If 3639:where 2530:a set 2453:space. 2238:a set 1970:space. 1709:a set 6771:(PDF) 6737:Dover 6715:(PDF) 6655:(PDF) 6225:(PDF) 6187:(PDF) 6044:Notes 5958:from 3083:space 2518:or a 2148:or a 2091:into 1939:of a 1935:is a 1674:or a 1015:or a 666:finer 344:be a 6804:OCLC 6794:ISBN 6745:ISBN 6699:OCLC 6689:ISBN 6659:ISBN 6632:ISBN 6593:ISBN 6572:ISBN 5850:The 5405:and 4972:let 4949:and 4164:The 3890:The 3346:The 3331:The 3324:The 3310:The 3223:and 3207:and 3052:For 3032:CG-3 3022:CG-2 3012:CG-1 2995:CG-3 2991:CG-2 2987:CG-1 2878:CGWH 2765:and 2429:(3) 2402:(2) 1946:(4) 1915:(3) 482:The 312:Let 139:open 34:, a 6847:Lab 6835:Lab 6280:doi 6237:doi 6154:Lab 6079:doi 5978:to 5854:in 5790:is 5767:to 5713:to 5146:on 5075:in 5027:to 4811:If 4673:If 4557:If 4514:of 4381:on 3836:to 3475:of 2931:on 2929:Lab 2915:of 1702:is 1488:or 871:in 836:in 696:in 664:is 562:of 514:on 401:or 141:in 137:is 74:or 61:or 30:In 6863:: 6802:. 6792:. 6788:: 6784:. 6755:MR 6753:. 6743:. 6725:; 6697:. 6687:. 6683:: 6393:^ 6276:23 6274:. 6270:. 6233:88 6231:. 6227:. 6200:^ 6160:^ 6115:^ 6073:. 6002:. 4152:A 4008:A 3405:). 3376:). 3321:). 3074:. 3070:, 3066:, 2993:, 2989:, 2972:. 2935:. 2483:. 1639:. 299:. 284:. 6845:n 6833:n 6810:. 6773:. 6761:. 6735:( 6717:. 6705:. 6667:. 6640:. 6628:5 6601:. 6351:. 6288:. 6282:: 6243:. 6239:: 6195:) 6191:( 6189:. 6152:n 6137:. 6085:. 6081:: 6075:9 5986:Y 5966:X 5940:X 5936:Y 5915:) 5910:X 5906:Y 5902:( 5899:k 5878:s 5875:u 5872:a 5869:H 5866:G 5863:C 5836:. 5832:p 5829:o 5826:T 5818:p 5815:o 5812:T 5809:G 5806:C 5778:X 5775:k 5755:X 5734:p 5731:o 5728:T 5725:G 5722:C 5700:p 5697:o 5694:T 5672:p 5669:o 5666:T 5663:G 5660:C 5638:s 5635:u 5632:a 5629:H 5626:G 5623:C 5600:p 5597:o 5594:T 5571:p 5568:o 5565:T 5562:G 5559:C 5531:X 5511:X 5508:k 5488:. 5485:X 5482:= 5479:X 5476:k 5456:X 5436:X 5433:k 5413:X 5393:X 5390:k 5370:. 5367:X 5364:k 5344:. 5315:K 5288:K 5281:A 5258:A 5238:X 5218:. 5215:X 5195:} 5186:K 5182:{ 5154:X 5130:X 5098:) 5095:Y 5092:, 5089:X 5086:( 5083:C 5059:X 5035:Y 5015:X 4995:) 4992:Y 4989:, 4986:X 4983:( 4980:C 4960:, 4957:Y 4937:X 4910:. 4907:X 4901:K 4881:Y 4875:K 4872:: 4867:K 4863:| 4859:f 4839:f 4819:X 4797:. 4794:X 4788:K 4785:: 4782:u 4762:K 4742:Y 4736:K 4733:: 4730:u 4724:f 4701:f 4681:X 4659:. 4656:X 4650:K 4630:Y 4624:K 4621:: 4616:K 4612:| 4608:f 4585:f 4565:X 4542:f 4522:f 4494:X 4474:Y 4468:X 4465:: 4462:f 4434:) 4431:Y 4425:X 4422:( 4419:k 4395:Y 4389:X 4332:Y 4326:X 4302:} 4296:, 4293:3 4290:, 4287:2 4284:, 4281:1 4278:{ 4274:/ 4269:R 4265:= 4262:Y 4234:} 4228:, 4225:3 4221:/ 4217:1 4214:, 4211:2 4207:/ 4203:1 4200:, 4197:1 4194:{ 4187:R 4183:= 4180:X 4129:] 4126:1 4123:, 4120:0 4117:( 4097:] 4094:1 4091:, 4088:0 4085:[ 4051:. 4048:X 4024:X 3991:i 3987:X 3964:I 3958:i 3954:) 3948:i 3944:X 3940:( 3918:i 3914:X 3908:i 3863:) 3860:U 3857:( 3852:1 3845:q 3824:q 3804:X 3798:U 3778:Y 3758:X 3752:Y 3749:: 3746:q 3726:, 3723:X 3683:1 3652:1 3627:] 3622:1 3614:, 3611:0 3608:[ 3605:= 3602:1 3599:+ 3594:1 3546:X 3526:Y 3506:X 3486:. 3483:Y 3459:X 3438:R 3417:Y 3388:Z 3359:R 3335:. 3328:. 3304:1 3290:X 3270:X 3260:1 3246:X 3191:1 3177:X 3157:; 3154:K 3134:X 3128:K 3108:, 3105:X 3099:} 3096:x 3093:{ 3081:1 3079:T 2927:n 2854:. 2851:] 2848:1 2845:, 2842:0 2839:( 2819:] 2816:1 2813:, 2810:0 2807:[ 2779:} 2776:1 2773:{ 2753:} 2750:0 2747:{ 2727:} 2724:X 2721:, 2718:} 2715:1 2712:{ 2709:, 2703:{ 2683:} 2680:1 2677:, 2674:0 2671:{ 2668:= 2665:X 2639:. 2636:X 2630:K 2610:K 2590:K 2584:A 2564:X 2544:X 2538:A 2502:X 2437:X 2410:X 2386:. 2383:X 2377:K 2374:: 2371:f 2351:K 2331:K 2311:) 2308:A 2305:( 2300:1 2293:f 2272:X 2252:X 2246:A 2223:. 2220:K 2200:X 2194:K 2191:: 2188:f 2164:X 2132:X 2102:. 2099:X 2079:) 2076:K 2073:( 2070:f 2050:) 2047:K 2044:( 2041:f 2021:K 2001:X 1995:K 1992:: 1989:f 1954:X 1923:X 1901:. 1898:K 1878:X 1872:K 1869:: 1866:f 1842:X 1818:. 1815:X 1809:K 1789:K 1769:K 1763:A 1743:X 1723:X 1717:A 1690:X 1658:X 1608:. 1603:G 1581:X 1559:F 1549:G 1525:F 1503:X 1472:X 1448:X 1425:, 1422:X 1402:. 1397:C 1389:K 1369:K 1349:K 1343:A 1323:X 1303:X 1297:A 1269:X 1249:. 1246:X 1224:C 1202:, 1199:X 1177:F 1153:. 1150:X 1147:= 1144:X 1141:k 1121:; 1118:X 1098:, 1095:X 1075:X 1053:F 1029:F 999:X 977:. 974:X 971:k 948:F 943:T 922:X 902:, 899:X 879:X 851:. 846:F 824:X 818:K 815:: 812:f 792:K 772:) 769:U 766:( 761:1 754:f 733:X 727:U 707:; 704:X 676:T 652:T 632:, 629:) 626:T 623:, 620:X 617:( 595:F 573:. 570:T 544:F 522:X 499:F 494:T 467:, 462:F 440:. 437:X 415:F 383:. 380:X 356:T 332:) 329:T 326:, 323:X 320:( 264:X 244:X 224:. 221:X 215:K 195:K 175:K 169:A 149:X 125:A 106:, 103:X 97:A 45:X 20:)

Index

Compactly generated Hausdorff space
topology
topological space
compact spaces
Hausdorff space
weak Hausdorff space
coherent
open
final topology
Hausdorff spaces
category of topological spaces
cartesian closed category
algebraic topology
topological space
topology
final topology
finer
coherent
Hausdorff
weak Hausdorff
Hausdorff
coherent
final topology
quotient space
topological sum
weakly locally compact
final topology
final topology
topological sum
locally compact Hausdorff

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