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Field of sets

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the open complexes generate all the complexes as a Boolean algebra. These related representations provide a well defined mathematical apparatus for studying the relationship between truth modalities (possibly true vs necessarily true, studied in modal logic) and notions of provability and refutability (studied in intuitionistic logic) and is thus deeply connected to the theory of
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sets trivially form a topological field of sets as each clopen set is its own interior and closure. The Stone representation of a Boolean algebra can be regarded as such a topological field of sets, however in general the topology of a topological field of sets can differ from the topology generated
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Every interior algebra can be represented as a topological field of sets with the underlying Boolean algebra of the interior algebra corresponding to the complexes of the topological field of sets and the interior and closure operators of the interior algebra corresponding to those of the topology.
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can be represented by a topological field of sets with the underlying lattice of the Heyting algebra corresponding to the lattice of complexes of the topological field of sets that are open in the topology. Moreover the topological field of sets representing a Heyting algebra may be chosen so that
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and provide a generalization of the Stone representation of Boolean algebras. Given an interior algebra we can form the Stone representation of its underlying Boolean algebra and then extend this to a topological field of sets by taking the topology generated by the complexes corresponding to the
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onto the two element Boolean algebra and form complexes by associating each element of the Boolean algebra with the set of such homomorphisms that map it to the top element. (The approach is equivalent as the ultrafilters of a Boolean algebra are precisely the pre-images of the top elements under
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and that an atom is below an element of a finite Boolean algebra if and only if that element is contained in the ultrafilter corresponding to the atom. This leads us to construct a representation of a Boolean algebra by taking its set of ultrafilters and forming complexes by associating with each
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In the case of Boolean algebras which are not complete and atomic we can still generalize the power set representation by considering fields of sets instead of whole power sets. To do this we first observe that the atoms of a finite Boolean algebra correspond to its
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Like the topological fields of sets, preorder fields play an important role in the representation theory of interior algebras. Every interior algebra can be represented as a preorder field with its interior and closure operators corresponding to those of the
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generated by the complexes of a field of sets. (It is just one of notable topologies on the given set of points; it often happens that another topology is given, with quite different properties, in particular, not zero-dimensional). Given a field of sets
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after the mathematicians who first generalized Stone's result for Boolean algebras to interior algebras and should not be confused with the Stone topology of the underlying Boolean algebra of the interior algebra which will be a finer topology).
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of the topology of the Stone representation.) While representation of modal algebras by general modal frames is possible for any normal modal algebra, it is only in the case of interior algebras (which correspond to the modal logic
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If a topological field of sets is both compact and algebraic then its topology is compact and its compact open sets are precisely the open complexes. Moreover, the open complexes form a base for the topology.
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of the interior algebra (which form a base for a topology). These complexes are then precisely the open complexes and the construction produces a Stone field representing the interior algebra - the
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element of the Boolean algebra the set of ultrafilters containing that element. This construction does indeed produce a representation of the Boolean algebra as a field of sets and is known as the
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simply for the underlying set of a probability space, particularly in the case where every subset is an event.) Measure spaces and probability spaces play a foundational role in
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theories are always algebraic, the complexes determining the preorder being the sets of possible worlds in which the sentences of the theory closed under necessity hold.
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these homomorphisms.) With this approach one sees that Stone representation can also be regarded as a generalization of the representation of finite Boolean algebras by
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of the Boolean algebra. The clopen sets of the Stone space are then precisely the complexes of the Stone representation. The area of mathematics known as
982:{\displaystyle F_{1}\cap \cdots \cap F_{n}\in {\mathcal {F}}{\text{ for all integers }}n\geq 1{\text{ and all }}F_{1},\ldots ,F_{n}\in {\mathcal {F}}.} 860:{\displaystyle F_{1}\cup \cdots \cup F_{n}\in {\mathcal {F}}{\text{ for all integers }}n\geq 1{\text{ and all }}F_{1},\ldots ,F_{n}\in {\mathcal {F}}.} 3241:
which already have a topology associated with them - this should not be confused with the topology generated by taking arbitrary unions of complexes.
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by taking arbitrary unions of complexes and in general the complexes of a topological field of sets need not be open or closed in the topology.
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is founded on the fact that the Stone representation of a Boolean algebra can be recovered purely from the corresponding Stone space whence a
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Every (normal) Boolean algebra with operators can be represented as a field of sets on a relational structure in the sense that it is
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The representation of interior algebras by preorder fields can be generalized to a representation theorem for arbitrary (normal)
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The Stone representation of a Boolean algebra is always separative and compact; the corresponding Boolean space is known as the
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we obtain an alternative representation of the interior algebra as a topological field of sets. (The topology of this "
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Similarly to topological fields of sets, preorder fields arise naturally in modal logic where the points represent the
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The listed statements are equivalent if (1) and (2) hold. The equivalence of statements (a) and (b) follows from
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which are fields of sets with an additional accessibility relation providing representations of modal algebras.
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respectively. Topological fields of sets representing these algebraic structures provide a related topological
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we often deal with measure spaces and probability spaces derived from rich mathematical structures such as
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Topological fields of sets play a fundamental role in the representation theory of interior algebras and
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theorem provides a Stone-type duality between countably complete Boolean algebras (which may be called
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and represent properties of outcomes for which we wish to assign probabilities. (Many use the term
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i.e. the closure and interior of every complex is also a complex. In other words,
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and represent potential outcomes while the measurable sets (complexes) are called
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of Boolean algebras. Every Boolean algebra can be represented as a field of sets.
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Topological fields of sets that are separative, compact and algebraic are called
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Handbook of Modal Logic, Volume 3 of Studies in Logic and Practical Reasoning
5110: 5024: 5013: 4983: – topology in which the intersection of any family of open sets is open 3917: 3042: 3010: 2945: 2862: 1992: 1260: 27:"Set algebra" redirects here. For the basic properties and laws of sets, see 4857:
and relations as operators can be viewed as a special case of relations. If
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the intersection of all the complexes contained in the filter is non-empty.
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Algebraic concept in measure theory, also referred to as an algebra of sets
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if and only if there is a base for its topology consisting of complexes.
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is both separative and compact (in which case it is described as being
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is the topology formed by taking arbitrary unions of complexes. Then
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This construction can be generalized to fields of sets on arbitrary
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on a relational structure, is the Boolean algebra with operators
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can be represented as a power set – the power set of its set of
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Patrick Blackburn, Johan F.A.K. van Benthem, Frank Wolter ed.,
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was first used in the case where the algebraic structure was a
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Fields of sets in the representation theory of Boolean algebras
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Assuming that (1) holds, this condition (2) is equivalent to:
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Complex algebras and fields of sets on relational structures
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A separative compact algebraic preorder field is said to be
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Separative and compact fields of sets: towards Stone duality
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that is an atom; the latter means that a nonempty subset of
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as an element, and is closed under the operations of taking
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if the following additional condition (4) is satisfied:
5101: – Family closed under subsets and countable unions 3480:. These two classes of algebraic structures provide the 5179:(3rd ed.). Cambridge: Cambridge University Press. 5070:
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which determines the preorder in the following manner:
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of this set and its power set) is a field of sets. If
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Any/both of the following equivalent conditions hold:
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that establishes a one-to-one correspondence between
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may be infinite) admits a representation of the form
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Any/all of the following equivalent conditions hold:
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exists between Boolean algebras and Boolean spaces.
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Stone's representation theorem for Boolean algebras
4992: – Identities and relationships involving sets 4951:to the complex algebra corresponding to the field. 3030:If an algebra over a set is closed under countable 2505:
Stone's representation theorem for Boolean algebras
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In other words, for all 3292:{\displaystyle (X,{\mathcal {T}},{\mathcal {F}})} 3049:. The complexes of a measurable space are called 2072:{\displaystyle S=f^{-1}=\{x\in X\mid f(x)\in B\}} 7707: 7692:{\displaystyle {\mathcal {F}}\neq \varnothing .} 5062: – Family of sets closed under intersection 3045:and the corresponding field of sets is called a 5113: – Relationship between certain categories 2629:{\displaystyle \mathbf {X} =(X,{\mathcal {F}})} 556:{\displaystyle \varnothing \in {\mathcal {F}}.} 5684:{\displaystyle \varnothing \in {\mathcal {F}}} 4167:{\displaystyle (X,(R_{i})_{I},{\mathcal {F}})} 3916:of the theory. They are a special case of the 5302: 3375:is a field of sets which is closed under the 3244: 2587:These definitions arise from considering the 2404:In other words: the atoms are a partition of 263:Fields of sets play an essential role in the 4929:{\displaystyle {\mathcal {C}}(\mathbf {X} )} 3885: 3842: 3802: 3759: 2507:and an example of a completion procedure in 2066: 2033: 5618:{\displaystyle A_{1}\cup A_{2}\cup \cdots } 5569:{\displaystyle A_{1}\cap A_{2}\cap \cdots } 3936:) if and only if it has a set of complexes 3202:and call its underlying measurable space a 2468:is the corresponding canonical surjection. 224:Fields of sets should not be confused with 5309: 5295: 5095: – Algebraic structure of set algebra 3206:. The points of a sample space are called 2526:Alternatively one can consider the set of 2483:can be constructed more generally for any 5651:{\displaystyle \Omega \in {\mathcal {F}}} 5396: 5171: 3532:Algebraic fields of sets and Stone fields 3612:{\displaystyle (X,\leq ,{\mathcal {F}})} 3021:Fields of sets with additional structure 2224:of the given field of sets, and defines 1100:itself as a field of sets. Elements of 7635:{\displaystyle A,B,A_{1},A_{2},\ldots } 4966:where a subset of a group was called a 3924:Algebraic and canonical preorder fields 3107:{\displaystyle (X,{\mathcal {F}},\mu )} 1578: 14: 7708: 3536:A topological field of sets is called 3491:(a formal mathematical abstraction of 7527:is a semiring where every complement 7255:{\displaystyle {\mathcal {F}}\colon } 5342:{\displaystyle {\mathcal {F}}\colon } 5089: – Function from sets to numbers 4230:i.e. a set with an indexed family of 2671:the corresponding topological space, 1636:(or, somewhat pedantically, the pair 4962:and has its origins in 19th century 4068:. The preorder fields obtained from 3431:forms a subalgebra of the power set 1417:Closed under countable intersections 591:{\displaystyle X\in {\mathcal {F}}.} 7220: 7213: 7175: 7154: 7147: 7140: 7121: 7114: 7083: 7055: 7048: 7041: 7025: 6930: 6851: 6832: 6794: 6787: 6767: 6760: 6753: 6723: 6716: 6688: 6681: 6674: 6655: 6648: 6641: 6634: 6627: 6620: 6613: 6606: 6599: 6577: 6570: 6549: 6542: 6535: 6528: 6521: 6499: 6485: 6478: 6464: 6457: 6450: 6443: 6424: 6403: 6389: 6382: 6375: 6368: 6349: 6314: 6307: 6300: 6293: 6225: 6218: 6211: 6189: 6182: 6144: 6130: 6101: 6080: 6013: 5981: 5927: 5878: 5871: 5847: 5798: 5791: 5719: 5712: 5159:Algebraic Polymodal Logic: A Survey 4009:{\displaystyle S\in {\mathcal {A}}} 3722:{\displaystyle S\in {\mathcal {F}}} 3467:{\displaystyle (X,{\mathcal {T}}).} 2354:{\displaystyle A\in {\mathcal {F}}} 2102:{\displaystyle S\in {\mathcal {F}}} 1069:{\displaystyle X\in {\mathcal {F}}} 414:that has the following properties: 236:. Similarly the term "algebra over 24: 7675: 7651: 7566: 7546:{\displaystyle \Omega \setminus A} 7534: 7500: 7389: 7345: 7276: 7244: 7227: 7206: 7168: 7161: 7128: 7076: 7069: 7062: 7009: 6994: 6987: 6980: 6973: 6970: 6967: 6960: 6953: 6946: 6914: 6899: 6892: 6885: 6878: 6875: 6872: 6865: 6858: 6816: 6801: 6780: 6777: 6774: 6737: 6730: 6709: 6702: 6695: 6662: 6584: 6563: 6556: 6506: 6492: 6471: 6431: 6417: 6410: 6396: 6356: 6342: 6335: 6328: 6321: 6274: 6267: 6260: 6253: 6246: 6239: 6232: 6196: 6137: 6094: 6087: 6059: 6052: 6045: 5974: 5967: 5960: 5953: 5946: 5934: 5920: 5913: 5906: 5899: 5892: 5885: 5854: 5840: 5833: 5826: 5819: 5812: 5805: 5775: 5768: 5761: 5754: 5747: 5740: 5733: 5726: 5676: 5643: 5635: 5520:{\displaystyle \Omega \setminus A} 5508: 5363: 5331: 5277: 5253: 4910: 4866: 4630: 4409: 4383: 4359: 4332: 4263:{\displaystyle (X,{\mathcal {F}})} 4252: 4156: 4112:. For this we consider structures 4001: 3945: 3826: 3823: 3743: 3740: 3737: 3714: 3684:{\displaystyle (X,{\mathcal {F}})} 3673: 3601: 3568: 3453: 3416: 3388: 3368:{\displaystyle (X,{\mathcal {F}})} 3357: 3328:{\displaystyle (X,{\mathcal {T}})} 3317: 3281: 3271: 3143:{\displaystyle (X,{\mathcal {F}})} 3132: 3090: 2960: 2874: 2716: 2700:{\displaystyle (X,{\mathcal {T}})} 2689: 2618: 2346: 2094: 1949: 1814: 1798:{\displaystyle (X,{\mathcal {F}})} 1787: 1550: 1494: 1442: 1396: 1340: 1288: 1230: 1210:{\displaystyle (X,{\mathcal {F}})} 1199: 1133: 1085: 1061: 1003: 971: 913: 849: 791: 727: 703: 656: 632: 580: 545: 483: 465: 346: 304:{\displaystyle (X,{\mathcal {F}})} 293: 120: 78:{\displaystyle (X,{\mathcal {F}})} 67: 25: 7732: 7683: 7537: 7471: 5511: 5482: 5208: 3986:if and only if for every complex 3026:Sigma algebras and measure spaces 870:Closed under finite intersections 454: 7221: 7214: 7207: 7176: 7169: 7162: 7155: 7148: 7141: 7122: 7115: 7084: 7077: 7070: 7063: 7056: 7049: 7042: 7026: 6988: 6981: 6974: 6961: 6954: 6947: 6931: 6893: 6886: 6879: 6866: 6859: 6852: 6833: 6795: 6788: 6781: 6768: 6761: 6754: 6738: 6731: 6724: 6717: 6710: 6703: 6696: 6689: 6682: 6675: 6656: 6649: 6642: 6635: 6628: 6621: 6614: 6607: 6600: 6578: 6571: 6564: 6557: 6550: 6543: 6536: 6529: 6522: 6500: 6493: 6486: 6479: 6472: 6465: 6458: 6451: 6444: 6425: 6418: 6411: 6404: 6397: 6390: 6383: 6376: 6369: 6350: 6343: 6336: 6329: 6322: 6315: 6308: 6301: 6294: 6275: 6268: 6261: 6254: 6247: 6240: 6233: 6226: 6219: 6212: 6190: 6183: 6138: 6131: 6095: 6088: 6081: 6060: 6053: 6046: 5975: 5968: 5961: 5954: 5947: 5928: 5921: 5914: 5907: 5900: 5893: 5886: 5879: 5872: 5848: 5841: 5834: 5827: 5820: 5813: 5806: 5799: 5792: 5776: 5769: 5762: 5755: 5748: 5741: 5734: 5727: 5720: 5713: 4919: 4368: 4286: 4278:) determined by a field of sets 2983: 2927: 2897: 2844: 2814: 2785: 2748: 2654: 2600: 2559:if and only if for every proper 1046:(with the same identity element 7577:{\displaystyle {\mathcal {F}}.} 7511:{\displaystyle {\mathcal {F}}.} 4219:{\displaystyle (X,(R_{i})_{I})} 4110:Boolean algebras with operators 3908:of a theory in the modal logic 2937:{\displaystyle T(\mathbf {X} )} 2854:{\displaystyle T(\mathbf {X} )} 2795:{\displaystyle T(\mathbf {X} )} 2758:{\displaystyle T(\mathbf {X} )} 2664:{\displaystyle T(\mathbf {X} )} 7659:{\displaystyle {\mathcal {F}}} 7284:{\displaystyle {\mathcal {F}}} 6168:{\displaystyle A_{i}\nearrow } 6162: 6037:{\displaystyle A_{i}\nearrow } 6031: 6005:{\displaystyle A_{i}\searrow } 5999: 5371:{\displaystyle {\mathcal {F}}} 5261:{\displaystyle {\mathcal {F}}} 5235:, Encyclopedia of Mathematics. 5195:Interior Algebras and Topology 5131: 5031:List of Boolean algebra topics 4923: 4915: 4874:{\displaystyle {\mathcal {F}}} 4829: 4791: 4693: 4661: 4444: 4435: 4421: 4378: 4372: 4364: 4337: 4293: 4257: 4241: 4213: 4204: 4190: 4181: 4161: 4142: 4128: 4119: 3953:{\displaystyle {\mathcal {A}}} 3836: 3830: 3753: 3747: 3678: 3662: 3638: 3626: 3606: 3584: 3562:McKinsey–Tarski Stone topology 3523:Given a topological space the 3458: 3442: 3424:{\displaystyle {\mathcal {F}}} 3396:{\displaystyle {\mathcal {T}}} 3362: 3346: 3322: 3306: 3286: 3260: 3137: 3121: 3101: 3079: 2968:{\displaystyle {\mathcal {F}}} 2931: 2923: 2882:{\displaystyle {\mathcal {F}}} 2848: 2840: 2789: 2781: 2752: 2744: 2724:{\displaystyle {\mathcal {T}}} 2694: 2678: 2658: 2650: 2623: 2607: 2260: 2254: 2057: 2051: 2027: 2021: 1957:{\displaystyle {\mathcal {F}}} 1924: 1875: 1856: 1822:{\displaystyle {\mathcal {F}}} 1792: 1776: 1662: 1643: 1238:{\displaystyle {\mathcal {F}}} 1204: 1188: 1141:{\displaystyle {\mathcal {F}}} 1093:{\displaystyle {\mathcal {F}}} 1011:{\displaystyle {\mathcal {F}}} 354:{\displaystyle {\mathcal {F}}} 298: 282: 270: 128:{\displaystyle {\mathcal {F}}} 72: 56: 13: 1: 5166:Varieties of complex algebras 5148: 2640:for a topology. We denote by 258:algebras over fields or rings 7480:{\displaystyle B\setminus A} 7421:{\displaystyle \varnothing } 6122:{\displaystyle A\subseteq B} 5491:{\displaystyle B\setminus A} 5403:{\displaystyle \,\supseteq } 4998: – mathematical concept 2990:{\displaystyle \mathbf {X} } 2904:{\displaystyle \mathbf {X} } 2821:{\displaystyle \mathbf {X} } 920: for all integers  798: for all integers  7: 7222: 7215: 7156: 7149: 7142: 7123: 7116: 7057: 7050: 7043: 7027: 6932: 6853: 6834: 6796: 6789: 6769: 6762: 6755: 6725: 6718: 6690: 6683: 6676: 6657: 6650: 6643: 6636: 6629: 6622: 6615: 6608: 6601: 6579: 6572: 6551: 6544: 6537: 6530: 6523: 6501: 6487: 6480: 6466: 6459: 6452: 6445: 6426: 6405: 6391: 6384: 6377: 6370: 6351: 6316: 6309: 6302: 6295: 6227: 6220: 6213: 6191: 6184: 6132: 6082: 5929: 5880: 5873: 5849: 5800: 5793: 5721: 5714: 5221:Encyclopedia of Mathematics 5021: – Algebraic structure 4973: 3928:A preorder field is called 10: 7737: 7642:are arbitrary elements of 7444: 7208: 7170: 7163: 7078: 7071: 7064: 6989: 6982: 6975: 6962: 6955: 6948: 6894: 6887: 6880: 6867: 6860: 6782: 6739: 6732: 6711: 6704: 6697: 6565: 6558: 6494: 6473: 6419: 6412: 6398: 6344: 6337: 6330: 6323: 6276: 6269: 6262: 6255: 6248: 6241: 6234: 6139: 6096: 6089: 6061: 6054: 6047: 5976: 5969: 5962: 5955: 5948: 5922: 5915: 5908: 5901: 5894: 5887: 5842: 5835: 5828: 5821: 5814: 5807: 5777: 5770: 5763: 5756: 5749: 5742: 5735: 5728: 5241: 4881:is the whole power set of 4093:Alexandrov bi-coreflection 3859: there exists a  3776: there exists a  3403:or equivalently under the 3245:Topological fields of sets 3150:is a measurable space and 2555:A field of sets is called 2544:A field of sets is called 2161:{\displaystyle B\subset Y} 2135:{\displaystyle B\in 2^{Y}} 748:Closed under finite unions 275:A field of sets is a pair 26: 5025:𝜆-system (Dynkin system) 4089:Alexandrov representation 3914:Lindenbaum–Tarski algebra 3644:{\displaystyle (X,\leq )} 3251:topological field of sets 3065:) and measurable spaces. 1881:{\displaystyle (Y,2^{Y})} 1668:{\displaystyle (Y,2^{Y})} 1076:). Many authors refer to 5124: 4569:is an operator of arity 4270:is a field of sets. The 2481:power set representation 2471:Similarly, every finite 2200:To this end one chooses 1933:{\displaystyle f:X\to Y} 7666:and it is assumed that 7461:where every complement 7395:{\displaystyle \Omega } 7351:{\displaystyle \Omega } 7235:Is necessarily true of 5462:{\displaystyle A\cup B} 5433:{\displaystyle A\cap B} 5322:Is necessarily true of 5283:{\displaystyle \Omega } 4954:(Historically the term 4718: there exist  4513:is a relation of arity 4479:{\displaystyle i\in I,} 3979:{\displaystyle x\leq y} 3063:abstract sigma algebras 2865:with compact open sets 1253: 1152:and are said to be the 7693: 7660: 7636: 7578: 7547: 7512: 7481: 7422: 7396: 7352: 7285: 7256: 7197: 7105: 7018: 6923: 6825: 6169: 6123: 6038: 6006: 5685: 5652: 5619: 5570: 5521: 5492: 5463: 5434: 5404: 5372: 5343: 5284: 5262: 4930: 4895: 4875: 4841: 4639: 4583: 4563: 4536: 4507: 4480: 4451: 4344: 4264: 4220: 4168: 4062: 4061:{\displaystyle y\in S} 4036: 4035:{\displaystyle x\in S} 4010: 3980: 3954: 3892: 3809: 3723: 3685: 3645: 3613: 3468: 3425: 3397: 3369: 3329: 3293: 3188: 3164: 3144: 3108: 2991: 2969: 2938: 2905: 2883: 2855: 2822: 2796: 2767:zero-dimensional space 2759: 2725: 2701: 2665: 2630: 2577: 2462: 2438: 2418: 2395: 2375: 2355: 2325: 2324:{\displaystyle x\in X} 2299: 2298:{\displaystyle x\in A} 2273: 2272:{\displaystyle f(x)=A} 2238: 2214: 2192: 2191:{\displaystyle 2^{n}.} 2162: 2136: 2103: 2073: 1985: 1958: 1934: 1908:; it means a function 1902: 1882: 1843: 1823: 1799: 1763: 1736: 1709: 1689: 1669: 1630: 1600: 1562: 1503: 1446: 1408: 1349: 1292: 1239: 1211: 1173: 1142: 1114: 1094: 1070: 1040: 1012: 983: 861: 739: 668: 592: 557: 522: 495: 437: 407: 382: 355: 328: 305: 250: 207: 175: 153: 129: 102: 79: 47:mathematical structure 7694: 7661: 7637: 7579: 7553:is equal to a finite 7548: 7513: 7487:is equal to a finite 7482: 7423: 7397: 7353: 7286: 7257: 7198: 7196:{\displaystyle \cap } 7106: 7104:{\displaystyle \cup } 7019: 6924: 6826: 6170: 6124: 6039: 6007: 5686: 5653: 5620: 5571: 5522: 5493: 5464: 5435: 5405: 5373: 5344: 5285: 5263: 4931: 4896: 4876: 4842: 4778: such that  4640: 4584: 4564: 4562:{\displaystyle f_{i}} 4537: 4508: 4506:{\displaystyle R_{i}} 4481: 4452: 4345: 4265: 4221: 4169: 4063: 4037: 4011: 3981: 3955: 3893: 3810: 3724: 3686: 3646: 3614: 3469: 3426: 3398: 3370: 3330: 3294: 3189: 3165: 3145: 3109: 2992: 2970: 2939: 2906: 2884: 2856: 2823: 2797: 2760: 2726: 2702: 2666: 2636:the complexes form a 2631: 2578: 2503:. It is the basis of 2463: 2444:is the corresponding 2439: 2419: 2401:cannot be a complex. 2396: 2376: 2356: 2326: 2300: 2274: 2239: 2220:to be the set of all 2215: 2193: 2163: 2137: 2104: 2074: 1986: 1984:{\displaystyle 2^{Y}} 1959: 1935: 1903: 1883: 1844: 1824: 1800: 1764: 1762:{\displaystyle 2^{n}} 1737: 1735:{\displaystyle 2^{Y}} 1710: 1690: 1670: 1631: 1629:{\displaystyle 2^{Y}} 1601: 1583:For an arbitrary set 1563: 1504: 1426: 1409: 1350: 1272: 1240: 1212: 1174: 1143: 1115: 1095: 1071: 1041: 1013: 984: 862: 740: 669: 593: 558: 523: 496: 438: 408: 383: 356: 329: 306: 265:representation theory 251: 208: 176: 154: 130: 103: 80: 49:consisting of a pair 7670: 7646: 7588: 7561: 7531: 7495: 7465: 7412: 7386: 7342: 7271: 7239: 7187: 7095: 6998: 6903: 6805: 6149: 6107: 6018: 5986: 5665: 5632: 5583: 5534: 5505: 5476: 5447: 5418: 5393: 5358: 5326: 5274: 5248: 4938:full complex algebra 4905: 4885: 4861: 4851:algebraic structures 4648: 4593: 4573: 4546: 4535:{\displaystyle n+1,} 4517: 4490: 4461: 4354: 4282: 4276:algebra of complexes 4238: 4228:relational structure 4178: 4116: 4046: 4020: 3990: 3964: 3940: 3918:general modal frames 3819: 3733: 3703: 3691:is a field of sets. 3659: 3623: 3581: 3558:Stone representation 3497:intuitionistic logic 3439: 3411: 3383: 3343: 3303: 3257: 3235:inner product spaces 3187:{\displaystyle \mu } 3178: 3163:{\displaystyle \mu } 3154: 3118: 3076: 2979: 2955: 2917: 2893: 2869: 2834: 2810: 2775: 2738: 2711: 2675: 2644: 2596: 2567: 2501:Stone representation 2452: 2428: 2408: 2385: 2365: 2335: 2309: 2283: 2248: 2228: 2204: 2172: 2146: 2113: 2083: 1999: 1968: 1944: 1912: 1892: 1853: 1833: 1809: 1773: 1746: 1719: 1699: 1679: 1640: 1613: 1587: 1579:Stone representation 1513: 1423: 1359: 1269: 1225: 1185: 1160: 1128: 1104: 1080: 1050: 1030: 998: 876: 754: 686: 677:Closed under binary 615: 606:Closed under binary 569: 534: 512: 448: 427: 394: 369: 341: 318: 279: 240: 194: 165: 143: 115: 92: 53: 5173:Johnstone, Peter T. 4981:Alexandrov topology 4234:defined on it, and 4085:Alexandrov topology 3697:Alexandrov topology 3518:intermediate logics 3482:algebraic semantics 3229:In applications to 3196:probability measure 1742:is finite (namely, 1695:is finite (namely, 934: and all  812: and all  710: for all  639: for all  472: for all  7689: 7656: 7632: 7574: 7543: 7508: 7477: 7418: 7392: 7348: 7281: 7252: 7193: 7101: 7014: 6919: 6821: 6165: 6119: 6034: 6002: 5681: 5648: 5615: 5566: 5517: 5488: 5459: 5430: 5400: 5368: 5339: 5280: 5258: 5075:Probability theory 4926: 4891: 4871: 4837: 4635: 4579: 4559: 4532: 4503: 4476: 4447: 4340: 4260: 4216: 4164: 4081:canonical preorder 4058: 4032: 4006: 3976: 3950: 3888: 3805: 3719: 3681: 3641: 3609: 3503:for these logics. 3464: 3421: 3393: 3365: 3325: 3289: 3239:topological groups 3224:probability theory 3184: 3174:defined on it. If 3160: 3140: 3104: 3041:), it is called a 3034:(hence also under 2987: 2965: 2934: 2901: 2879: 2851: 2818: 2792: 2755: 2721: 2697: 2661: 2626: 2573: 2458: 2434: 2414: 2391: 2371: 2351: 2321: 2295: 2269: 2234: 2210: 2188: 2158: 2132: 2099: 2069: 1981: 1954: 1930: 1898: 1878: 1839: 1819: 1795: 1759: 1732: 1705: 1685: 1665: 1626: 1599:{\displaystyle Y,} 1596: 1558: 1499: 1404: 1345: 1235: 1207: 1172:{\displaystyle X.} 1169: 1138: 1124:while elements of 1110: 1090: 1066: 1036: 1008: 979: 857: 735: 664: 588: 553: 518: 491: 433: 406:{\displaystyle X,} 403: 381:{\displaystyle X,} 378: 351: 324: 301: 246: 206:{\displaystyle X,} 203: 182:that contains the 171: 149: 125: 98: 75: 7704: 7703: 5216:"Algebra of sets" 4894:{\displaystyle X} 4779: 4719: 4582:{\displaystyle n} 3874: 3860: 3791: 3777: 3405:interior operator 3337:topological space 3200:probability space 2576:{\displaystyle X} 2490:Boolean algebra. 2461:{\displaystyle f} 2437:{\displaystyle Y} 2417:{\displaystyle X} 2394:{\displaystyle A} 2374:{\displaystyle A} 2237:{\displaystyle f} 2213:{\displaystyle Y} 1901:{\displaystyle Y} 1842:{\displaystyle X} 1708:{\displaystyle n} 1688:{\displaystyle Y} 1113:{\displaystyle X} 1039:{\displaystyle X} 1022:of the power set 935: 921: 813: 799: 711: 640: 521:{\displaystyle X} 473: 436:{\displaystyle X} 327:{\displaystyle X} 249:{\displaystyle X} 234:fields in physics 174:{\displaystyle X} 152:{\displaystyle X} 101:{\displaystyle X} 16:(Redirected from 7728: 7721:Families of sets 7698: 7696: 7695: 7690: 7679: 7678: 7665: 7663: 7662: 7657: 7655: 7654: 7641: 7639: 7638: 7633: 7625: 7624: 7612: 7611: 7583: 7581: 7580: 7575: 7570: 7569: 7552: 7550: 7549: 7544: 7517: 7515: 7514: 7509: 7504: 7503: 7486: 7484: 7483: 7478: 7458: 7446:Additionally, a 7440: 7429: 7428: 7427: 7425: 7424: 7419: 7403: 7402: 7401: 7399: 7398: 7393: 7377: 7376: 7368: 7367: 7359: 7358: 7357: 7355: 7354: 7349: 7331: 7330: 7322: 7321: 7313: 7312: 7304: 7295: 7294: 7290: 7288: 7287: 7282: 7280: 7279: 7263: 7262: 7261: 7259: 7258: 7253: 7248: 7247: 7225: 7224: 7218: 7217: 7211: 7210: 7204: 7202: 7200: 7199: 7194: 7183:(even arbitrary 7180: 7173: 7172: 7166: 7165: 7159: 7158: 7152: 7151: 7145: 7144: 7137: 7126: 7125: 7119: 7118: 7112: 7110: 7108: 7107: 7102: 7091:(even arbitrary 7088: 7081: 7080: 7074: 7073: 7067: 7066: 7060: 7059: 7053: 7052: 7046: 7045: 7038: 7030: 7029: 7023: 7021: 7020: 7015: 7013: 7012: 6992: 6991: 6985: 6984: 6978: 6977: 6965: 6964: 6958: 6957: 6951: 6950: 6943: 6935: 6934: 6928: 6926: 6925: 6920: 6918: 6917: 6897: 6896: 6890: 6889: 6883: 6882: 6870: 6869: 6863: 6862: 6856: 6855: 6848: 6845: 6837: 6836: 6830: 6828: 6827: 6822: 6820: 6819: 6799: 6798: 6792: 6791: 6785: 6784: 6772: 6771: 6765: 6764: 6758: 6757: 6750: 6742: 6741: 6735: 6734: 6728: 6727: 6721: 6720: 6714: 6713: 6707: 6706: 6700: 6699: 6693: 6692: 6686: 6685: 6679: 6678: 6671: 6660: 6659: 6653: 6652: 6646: 6645: 6639: 6638: 6632: 6631: 6625: 6624: 6618: 6617: 6611: 6610: 6604: 6603: 6596: 6593: 6582: 6581: 6575: 6574: 6568: 6567: 6561: 6560: 6554: 6553: 6547: 6546: 6540: 6539: 6533: 6532: 6526: 6525: 6518: 6517: 6504: 6503: 6497: 6496: 6490: 6489: 6483: 6482: 6476: 6475: 6469: 6468: 6462: 6461: 6455: 6454: 6448: 6447: 6440: 6429: 6428: 6422: 6421: 6415: 6414: 6408: 6407: 6401: 6400: 6394: 6393: 6387: 6386: 6380: 6379: 6373: 6372: 6365: 6354: 6353: 6347: 6346: 6340: 6339: 6333: 6332: 6326: 6325: 6319: 6318: 6312: 6311: 6305: 6304: 6298: 6297: 6290: 6289: 6288:(Measure theory) 6279: 6278: 6272: 6271: 6265: 6264: 6258: 6257: 6251: 6250: 6244: 6243: 6237: 6236: 6230: 6229: 6223: 6222: 6216: 6215: 6208: 6207: 6194: 6193: 6187: 6186: 6174: 6172: 6171: 6166: 6161: 6160: 6142: 6141: 6135: 6134: 6128: 6126: 6125: 6120: 6099: 6098: 6092: 6091: 6085: 6084: 6077: 6076: 6072: 6064: 6063: 6057: 6056: 6050: 6049: 6043: 6041: 6040: 6035: 6030: 6029: 6011: 6009: 6008: 6003: 5998: 5997: 5979: 5978: 5972: 5971: 5965: 5964: 5958: 5957: 5951: 5950: 5943: 5932: 5931: 5925: 5924: 5918: 5917: 5911: 5910: 5904: 5903: 5897: 5896: 5890: 5889: 5883: 5882: 5876: 5875: 5869: 5867: 5864: 5852: 5851: 5845: 5844: 5838: 5837: 5831: 5830: 5824: 5823: 5817: 5816: 5810: 5809: 5803: 5802: 5796: 5795: 5789: 5780: 5779: 5773: 5772: 5766: 5765: 5759: 5758: 5752: 5751: 5745: 5744: 5738: 5737: 5731: 5730: 5724: 5723: 5717: 5716: 5710: 5707: 5698: 5691: 5690: 5688: 5687: 5682: 5680: 5679: 5658: 5657: 5655: 5654: 5649: 5647: 5646: 5625: 5624: 5622: 5621: 5616: 5608: 5607: 5595: 5594: 5576: 5575: 5573: 5572: 5567: 5559: 5558: 5546: 5545: 5527: 5526: 5524: 5523: 5518: 5498: 5497: 5495: 5494: 5489: 5469: 5468: 5466: 5465: 5460: 5440: 5439: 5437: 5436: 5431: 5411: 5409: 5407: 5406: 5401: 5382: 5381: 5377: 5375: 5374: 5369: 5367: 5366: 5350: 5349: 5348: 5346: 5345: 5340: 5335: 5334: 5311: 5304: 5297: 5290: 5289: 5287: 5286: 5281: 5267: 5265: 5264: 5259: 5257: 5256: 5239: 5238: 5229: 5204:, Elsevier, 2006 5193:Naturman, C.A., 5190: 5142: 5139:De Morgan's laws 5135: 5071: 5066:Preordered field 5059: 5053: 5050: 5041: 5019:Interior algebra 5007: 5001: 4986: 4935: 4933: 4932: 4927: 4922: 4914: 4913: 4900: 4898: 4897: 4892: 4880: 4878: 4877: 4872: 4870: 4869: 4846: 4844: 4843: 4838: 4836: 4832: 4822: 4821: 4803: 4802: 4790: 4789: 4780: 4777: 4775: 4774: 4762: 4761: 4743: 4742: 4730: 4729: 4720: 4717: 4692: 4691: 4673: 4672: 4660: 4659: 4644: 4642: 4641: 4636: 4634: 4633: 4624: 4623: 4605: 4604: 4588: 4586: 4585: 4580: 4568: 4566: 4565: 4560: 4558: 4557: 4541: 4539: 4538: 4533: 4512: 4510: 4509: 4504: 4502: 4501: 4485: 4483: 4482: 4477: 4456: 4454: 4453: 4448: 4443: 4442: 4433: 4432: 4387: 4386: 4371: 4363: 4362: 4349: 4347: 4346: 4341: 4336: 4335: 4326: 4325: 4320: 4316: 4315: 4289: 4269: 4267: 4266: 4261: 4256: 4255: 4225: 4223: 4222: 4217: 4212: 4211: 4202: 4201: 4173: 4171: 4170: 4165: 4160: 4159: 4150: 4149: 4140: 4139: 4067: 4065: 4064: 4059: 4041: 4039: 4038: 4033: 4015: 4013: 4012: 4007: 4005: 4004: 3985: 3983: 3982: 3977: 3959: 3957: 3956: 3951: 3949: 3948: 3906:Kripke semantics 3897: 3895: 3894: 3889: 3875: 3873: with  3872: 3861: 3858: 3829: 3814: 3812: 3811: 3806: 3792: 3790: with  3789: 3778: 3775: 3746: 3728: 3726: 3725: 3720: 3718: 3717: 3690: 3688: 3687: 3682: 3677: 3676: 3650: 3648: 3647: 3642: 3618: 3616: 3615: 3610: 3605: 3604: 3514:modal companions 3478:Heyting algebras 3473: 3471: 3470: 3465: 3457: 3456: 3433:interior algebra 3430: 3428: 3427: 3422: 3420: 3419: 3402: 3400: 3399: 3394: 3392: 3391: 3377:closure operator 3374: 3372: 3371: 3366: 3361: 3360: 3334: 3332: 3331: 3326: 3321: 3320: 3298: 3296: 3295: 3290: 3285: 3284: 3275: 3274: 3193: 3191: 3190: 3185: 3169: 3167: 3166: 3161: 3149: 3147: 3146: 3141: 3136: 3135: 3113: 3111: 3110: 3105: 3094: 3093: 3047:measurable space 2996: 2994: 2993: 2988: 2986: 2974: 2972: 2971: 2966: 2964: 2963: 2943: 2941: 2940: 2935: 2930: 2910: 2908: 2907: 2902: 2900: 2888: 2886: 2885: 2880: 2878: 2877: 2860: 2858: 2857: 2852: 2847: 2827: 2825: 2824: 2819: 2817: 2801: 2799: 2798: 2793: 2788: 2764: 2762: 2761: 2756: 2751: 2730: 2728: 2727: 2722: 2720: 2719: 2706: 2704: 2703: 2698: 2693: 2692: 2670: 2668: 2667: 2662: 2657: 2635: 2633: 2632: 2627: 2622: 2621: 2603: 2582: 2580: 2579: 2574: 2467: 2465: 2464: 2459: 2443: 2441: 2440: 2435: 2423: 2421: 2420: 2415: 2400: 2398: 2397: 2392: 2380: 2378: 2377: 2372: 2360: 2358: 2357: 2352: 2350: 2349: 2330: 2328: 2327: 2322: 2304: 2302: 2301: 2296: 2278: 2276: 2275: 2270: 2243: 2241: 2240: 2235: 2219: 2217: 2216: 2211: 2197: 2195: 2194: 2189: 2184: 2183: 2167: 2165: 2164: 2159: 2141: 2139: 2138: 2133: 2131: 2130: 2108: 2106: 2105: 2100: 2098: 2097: 2078: 2076: 2075: 2070: 2020: 2019: 1990: 1988: 1987: 1982: 1980: 1979: 1963: 1961: 1960: 1955: 1953: 1952: 1939: 1937: 1936: 1931: 1907: 1905: 1904: 1899: 1887: 1885: 1884: 1879: 1874: 1873: 1848: 1846: 1845: 1840: 1828: 1826: 1825: 1820: 1818: 1817: 1804: 1802: 1801: 1796: 1791: 1790: 1768: 1766: 1765: 1760: 1758: 1757: 1741: 1739: 1738: 1733: 1731: 1730: 1715:-element), then 1714: 1712: 1711: 1706: 1694: 1692: 1691: 1686: 1674: 1672: 1671: 1666: 1661: 1660: 1635: 1633: 1632: 1627: 1625: 1624: 1605: 1603: 1602: 1597: 1567: 1565: 1564: 1559: 1554: 1553: 1538: 1537: 1525: 1524: 1508: 1506: 1505: 1500: 1498: 1497: 1482: 1481: 1469: 1468: 1456: 1455: 1445: 1440: 1413: 1411: 1410: 1405: 1400: 1399: 1384: 1383: 1371: 1370: 1354: 1352: 1351: 1346: 1344: 1343: 1328: 1327: 1315: 1314: 1302: 1301: 1291: 1286: 1244: 1242: 1241: 1236: 1234: 1233: 1221:and the algebra 1216: 1214: 1213: 1208: 1203: 1202: 1181:A field of sets 1178: 1176: 1175: 1170: 1147: 1145: 1144: 1139: 1137: 1136: 1119: 1117: 1116: 1111: 1099: 1097: 1096: 1091: 1089: 1088: 1075: 1073: 1072: 1067: 1065: 1064: 1045: 1043: 1042: 1037: 1017: 1015: 1014: 1009: 1007: 1006: 994:In other words, 988: 986: 985: 980: 975: 974: 965: 964: 946: 945: 936: 933: 922: 919: 917: 916: 907: 906: 888: 887: 866: 864: 863: 858: 853: 852: 843: 842: 824: 823: 814: 811: 800: 797: 795: 794: 785: 784: 766: 765: 744: 742: 741: 736: 731: 730: 712: 709: 707: 706: 673: 671: 670: 665: 660: 659: 641: 638: 636: 635: 597: 595: 594: 589: 584: 583: 562: 560: 559: 554: 549: 548: 527: 525: 524: 519: 500: 498: 497: 492: 487: 486: 474: 471: 469: 468: 442: 440: 439: 434: 412: 410: 409: 404: 387: 385: 384: 379: 360: 358: 357: 352: 350: 349: 333: 331: 330: 325: 311:consisting of a 310: 308: 307: 302: 297: 296: 260:in ring theory. 255: 253: 252: 247: 212: 210: 209: 204: 180: 178: 177: 172: 158: 156: 155: 150: 134: 132: 131: 126: 124: 123: 107: 105: 104: 99: 85:consisting of a 84: 82: 81: 76: 71: 70: 21: 7736: 7735: 7731: 7730: 7729: 7727: 7726: 7725: 7716:Boolean algebra 7706: 7705: 7699: 7674: 7673: 7671: 7668: 7667: 7650: 7649: 7647: 7644: 7643: 7620: 7616: 7607: 7603: 7589: 7586: 7585: 7584: 7565: 7564: 7562: 7559: 7558: 7532: 7529: 7528: 7518: 7499: 7498: 7496: 7493: 7492: 7466: 7463: 7462: 7456: 7437: 7435: 7432: 7413: 7410: 7409: 7407: 7406: 7387: 7384: 7383: 7381: 7380: 7374: 7372: 7371: 7365: 7363: 7362: 7343: 7340: 7339: 7337: 7335: 7334: 7328: 7326: 7325: 7319: 7317: 7316: 7310: 7308: 7307: 7301: 7298: 7275: 7274: 7272: 7269: 7268: 7266: 7265: 7264: 7243: 7242: 7240: 7237: 7236: 7234: 7233: 7188: 7185: 7184: 7182: 7181: 7136:Closed Topology 7135: 7096: 7093: 7092: 7090: 7089: 7036: 7008: 7007: 6999: 6996: 6995: 6941: 6913: 6912: 6904: 6901: 6900: 6846: 6843: 6815: 6814: 6806: 6803: 6802: 6748: 6669: 6594: 6591: 6515: 6513: 6438: 6363: 6287: 6285: 6205: 6203: 6176: 6156: 6152: 6150: 6147: 6146: 6108: 6105: 6104: 6103: 6075:(Dynkin System) 6074: 6073: 6070: 6025: 6021: 6019: 6016: 6015: 5993: 5989: 5987: 5984: 5983: 5941: 5865: 5862: 5860: 5785: 5705: 5703: 5694: 5675: 5674: 5666: 5663: 5662: 5661: 5642: 5641: 5633: 5630: 5629: 5628: 5603: 5599: 5590: 5586: 5584: 5581: 5580: 5579: 5554: 5550: 5541: 5537: 5535: 5532: 5531: 5530: 5506: 5503: 5502: 5501: 5477: 5474: 5473: 5472: 5448: 5445: 5444: 5443: 5419: 5416: 5415: 5414: 5394: 5391: 5390: 5388: 5385: 5362: 5361: 5359: 5356: 5355: 5353: 5352: 5351: 5330: 5329: 5327: 5324: 5323: 5321: 5320: 5315: 5275: 5272: 5271: 5252: 5251: 5249: 5246: 5245: 5242: 5233:Algebra of sets 5214: 5211: 5187: 5164:Goldblatt, R., 5151: 5146: 5145: 5136: 5132: 5127: 5122: 5069: 5057: 5051: 5048: 5047: – theorem 5039: 5005: 4999: 4990:Algebra of sets 4984: 4976: 4918: 4909: 4908: 4906: 4903: 4902: 4886: 4883: 4882: 4865: 4864: 4862: 4859: 4858: 4817: 4813: 4798: 4794: 4785: 4781: 4776: 4770: 4766: 4757: 4753: 4738: 4734: 4725: 4721: 4716: 4703: 4699: 4687: 4683: 4668: 4664: 4655: 4651: 4649: 4646: 4645: 4629: 4628: 4619: 4615: 4600: 4596: 4594: 4591: 4590: 4574: 4571: 4570: 4553: 4549: 4547: 4544: 4543: 4518: 4515: 4514: 4497: 4493: 4491: 4488: 4487: 4462: 4459: 4458: 4438: 4434: 4428: 4424: 4382: 4381: 4367: 4358: 4357: 4355: 4352: 4351: 4331: 4330: 4321: 4311: 4307: 4303: 4302: 4285: 4283: 4280: 4279: 4272:complex algebra 4251: 4250: 4239: 4236: 4235: 4207: 4203: 4197: 4193: 4179: 4176: 4175: 4155: 4154: 4145: 4141: 4135: 4131: 4117: 4114: 4113: 4106: 4047: 4044: 4043: 4021: 4018: 4017: 4000: 3999: 3991: 3988: 3987: 3965: 3962: 3961: 3944: 3943: 3941: 3938: 3937: 3926: 3902:possible worlds 3871: 3857: 3822: 3820: 3817: 3816: 3788: 3774: 3736: 3734: 3731: 3730: 3713: 3712: 3704: 3701: 3700: 3672: 3671: 3660: 3657: 3656: 3624: 3621: 3620: 3600: 3599: 3582: 3579: 3578: 3571: 3569:Preorder fields 3534: 3509:Heyting algebra 3493:epistemic logic 3452: 3451: 3440: 3437: 3436: 3415: 3414: 3412: 3409: 3408: 3387: 3386: 3384: 3381: 3380: 3356: 3355: 3344: 3341: 3340: 3316: 3315: 3304: 3301: 3300: 3280: 3279: 3270: 3269: 3258: 3255: 3254: 3247: 3179: 3176: 3175: 3155: 3152: 3151: 3131: 3130: 3119: 3116: 3115: 3089: 3088: 3077: 3074: 3073: 3051:measurable sets 3028: 3023: 2982: 2980: 2977: 2976: 2975:if and only if 2959: 2958: 2956: 2953: 2952: 2926: 2918: 2915: 2914: 2896: 2894: 2891: 2890: 2889:if and only if 2873: 2872: 2870: 2867: 2866: 2843: 2835: 2832: 2831: 2813: 2811: 2808: 2807: 2806:if and only if 2804:Hausdorff space 2784: 2776: 2773: 2772: 2747: 2739: 2736: 2735: 2715: 2714: 2712: 2709: 2708: 2688: 2687: 2676: 2673: 2672: 2653: 2645: 2642: 2641: 2617: 2616: 2599: 2597: 2594: 2593: 2568: 2565: 2564: 2541: 2473:Boolean algebra 2453: 2450: 2449: 2429: 2426: 2425: 2409: 2406: 2405: 2386: 2383: 2382: 2381:different from 2366: 2363: 2362: 2345: 2344: 2336: 2333: 2332: 2310: 2307: 2306: 2284: 2281: 2280: 2249: 2246: 2245: 2229: 2226: 2225: 2205: 2202: 2201: 2179: 2175: 2173: 2170: 2169: 2147: 2144: 2143: 2126: 2122: 2114: 2111: 2110: 2093: 2092: 2084: 2081: 2080: 2012: 2008: 2000: 1997: 1996: 1975: 1971: 1969: 1966: 1965: 1948: 1947: 1945: 1942: 1941: 1913: 1910: 1909: 1893: 1890: 1889: 1869: 1865: 1854: 1851: 1850: 1834: 1831: 1830: 1813: 1812: 1810: 1807: 1806: 1786: 1785: 1774: 1771: 1770: 1753: 1749: 1747: 1744: 1743: 1726: 1722: 1720: 1717: 1716: 1700: 1697: 1696: 1680: 1677: 1676: 1656: 1652: 1641: 1638: 1637: 1620: 1616: 1614: 1611: 1610: 1588: 1585: 1584: 1581: 1576: 1549: 1548: 1533: 1529: 1520: 1516: 1514: 1511: 1510: 1493: 1492: 1477: 1473: 1464: 1460: 1451: 1447: 1441: 1430: 1424: 1421: 1420: 1395: 1394: 1379: 1375: 1366: 1362: 1360: 1357: 1356: 1339: 1338: 1323: 1319: 1310: 1306: 1297: 1293: 1287: 1276: 1270: 1267: 1266: 1229: 1228: 1226: 1223: 1222: 1219:σ-field of sets 1198: 1197: 1186: 1183: 1182: 1161: 1158: 1157: 1154:admissible sets 1132: 1131: 1129: 1126: 1125: 1105: 1102: 1101: 1084: 1083: 1081: 1078: 1077: 1060: 1059: 1051: 1048: 1047: 1031: 1028: 1027: 1024:Boolean algebra 1002: 1001: 999: 996: 995: 970: 969: 960: 956: 941: 937: 932: 918: 912: 911: 902: 898: 883: 879: 877: 874: 873: 848: 847: 838: 834: 819: 815: 810: 796: 790: 789: 780: 776: 761: 757: 755: 752: 751: 726: 725: 708: 702: 701: 687: 684: 683: 655: 654: 637: 631: 630: 616: 613: 612: 579: 578: 570: 567: 566: 544: 543: 535: 532: 531: 530:as an element: 513: 510: 509: 482: 481: 470: 464: 463: 449: 446: 445: 428: 425: 424: 421:complementation 395: 392: 391: 370: 367: 366: 345: 344: 342: 339: 338: 319: 316: 315: 292: 291: 280: 277: 276: 273: 241: 238: 237: 195: 192: 191: 166: 163: 162: 144: 141: 140: 119: 118: 116: 113: 112: 93: 90: 89: 66: 65: 54: 51: 50: 35: 32: 29:Algebra of sets 23: 22: 15: 12: 11: 5: 7734: 7724: 7723: 7718: 7702: 7701: 7688: 7685: 7682: 7677: 7653: 7631: 7628: 7623: 7619: 7615: 7610: 7606: 7602: 7599: 7596: 7593: 7573: 7568: 7555:disjoint union 7542: 7539: 7536: 7525: 7507: 7502: 7489:disjoint union 7476: 7473: 7470: 7452: 7442: 7441: 7430: 7417: 7404: 7391: 7378: 7369: 7360: 7347: 7332: 7323: 7314: 7305: 7296: 7278: 7251: 7246: 7230: 7229: 7226: 7219: 7212: 7205: 7192: 7174: 7167: 7160: 7153: 7146: 7139: 7131: 7130: 7127: 7120: 7113: 7100: 7082: 7075: 7068: 7061: 7054: 7047: 7040: 7032: 7031: 7024: 7011: 7006: 7003: 6993: 6986: 6979: 6972: 6969: 6966: 6959: 6952: 6945: 6942:Filter subbase 6937: 6936: 6929: 6916: 6911: 6908: 6898: 6891: 6884: 6877: 6874: 6871: 6864: 6857: 6850: 6839: 6838: 6831: 6818: 6813: 6810: 6800: 6793: 6786: 6779: 6776: 6773: 6766: 6759: 6752: 6744: 6743: 6736: 6729: 6722: 6715: 6708: 6701: 6694: 6687: 6680: 6673: 6665: 6664: 6661: 6654: 6647: 6640: 6633: 6626: 6619: 6612: 6605: 6598: 6587: 6586: 6583: 6576: 6569: 6562: 6555: 6548: 6541: 6534: 6527: 6520: 6509: 6508: 6505: 6498: 6491: 6484: 6477: 6470: 6463: 6456: 6449: 6442: 6434: 6433: 6430: 6423: 6416: 6409: 6402: 6395: 6388: 6381: 6374: 6367: 6359: 6358: 6355: 6348: 6341: 6334: 6327: 6320: 6313: 6306: 6299: 6292: 6281: 6280: 6273: 6266: 6259: 6252: 6245: 6238: 6231: 6224: 6217: 6210: 6206:(Order theory) 6199: 6198: 6195: 6188: 6181: 6164: 6159: 6155: 6143: 6136: 6129: 6118: 6115: 6112: 6100: 6093: 6086: 6079: 6066: 6065: 6058: 6051: 6044: 6033: 6028: 6024: 6012: 6001: 5996: 5992: 5980: 5973: 5966: 5959: 5952: 5945: 5942:Monotone class 5937: 5936: 5933: 5926: 5919: 5912: 5905: 5898: 5891: 5884: 5877: 5870: 5857: 5856: 5853: 5846: 5839: 5832: 5825: 5818: 5811: 5804: 5797: 5790: 5782: 5781: 5774: 5767: 5760: 5753: 5746: 5739: 5732: 5725: 5718: 5711: 5700: 5699: 5692: 5678: 5673: 5670: 5659: 5645: 5640: 5637: 5626: 5614: 5611: 5606: 5602: 5598: 5593: 5589: 5577: 5565: 5562: 5557: 5553: 5549: 5544: 5540: 5528: 5516: 5513: 5510: 5499: 5487: 5484: 5481: 5470: 5458: 5455: 5452: 5441: 5429: 5426: 5423: 5412: 5399: 5383: 5365: 5338: 5333: 5317: 5316: 5314: 5313: 5306: 5299: 5291: 5279: 5255: 5237: 5236: 5230: 5210: 5209:External links 5207: 5206: 5205: 5198: 5191: 5185: 5169: 5162: 5150: 5147: 5144: 5143: 5129: 5128: 5126: 5123: 5121: 5120: 5114: 5108: 5102: 5096: 5090: 5084: 5078: 5072: 5063: 5054: 5045:Monotone class 5042: 5036:Measure theory 5033: 5028: 5022: 5016: 5011: 5002: 4993: 4987: 4977: 4975: 4972: 4925: 4921: 4917: 4912: 4890: 4868: 4835: 4831: 4828: 4825: 4820: 4816: 4812: 4809: 4806: 4801: 4797: 4793: 4788: 4784: 4773: 4769: 4765: 4760: 4756: 4752: 4749: 4746: 4741: 4737: 4733: 4728: 4724: 4715: 4712: 4709: 4706: 4702: 4698: 4695: 4690: 4686: 4682: 4679: 4676: 4671: 4667: 4663: 4658: 4654: 4632: 4627: 4622: 4618: 4614: 4611: 4608: 4603: 4599: 4578: 4556: 4552: 4531: 4528: 4525: 4522: 4500: 4496: 4475: 4472: 4469: 4466: 4457:where for all 4446: 4441: 4437: 4431: 4427: 4423: 4420: 4417: 4414: 4411: 4408: 4405: 4402: 4399: 4396: 4393: 4390: 4385: 4380: 4377: 4374: 4370: 4366: 4361: 4339: 4334: 4329: 4324: 4319: 4314: 4310: 4306: 4301: 4298: 4295: 4292: 4288: 4259: 4254: 4249: 4246: 4243: 4215: 4210: 4206: 4200: 4196: 4192: 4189: 4186: 4183: 4163: 4158: 4153: 4148: 4144: 4138: 4134: 4130: 4127: 4124: 4121: 4105: 4102: 4091:" is just the 4057: 4054: 4051: 4031: 4028: 4025: 4003: 3998: 3995: 3975: 3972: 3969: 3947: 3925: 3922: 3887: 3884: 3881: 3878: 3870: 3867: 3864: 3856: 3853: 3850: 3847: 3844: 3841: 3838: 3835: 3832: 3828: 3825: 3804: 3801: 3798: 3795: 3787: 3784: 3781: 3773: 3770: 3767: 3764: 3761: 3758: 3755: 3752: 3749: 3745: 3742: 3739: 3716: 3711: 3708: 3680: 3675: 3670: 3667: 3664: 3653:preordered set 3640: 3637: 3634: 3631: 3628: 3608: 3603: 3598: 3595: 3592: 3589: 3586: 3575:preorder field 3570: 3567: 3533: 3530: 3463: 3460: 3455: 3450: 3447: 3444: 3418: 3390: 3364: 3359: 3354: 3351: 3348: 3324: 3319: 3314: 3311: 3308: 3288: 3283: 3278: 3273: 3268: 3265: 3262: 3246: 3243: 3226:respectively. 3220:measure theory 3198:we speak of a 3183: 3159: 3139: 3134: 3129: 3126: 3123: 3103: 3100: 3097: 3092: 3087: 3084: 3081: 3027: 3024: 3022: 3019: 3003: 3002: 2985: 2962: 2933: 2929: 2925: 2922: 2912: 2899: 2876: 2850: 2846: 2842: 2839: 2829: 2828:is separative. 2816: 2791: 2787: 2783: 2780: 2770: 2754: 2750: 2746: 2743: 2718: 2696: 2691: 2686: 2683: 2680: 2660: 2656: 2652: 2649: 2625: 2620: 2615: 2612: 2609: 2606: 2602: 2585: 2584: 2572: 2553: 2550:differentiated 2540: 2537: 2457: 2433: 2413: 2390: 2370: 2348: 2343: 2340: 2331:and a complex 2320: 2317: 2314: 2294: 2291: 2288: 2268: 2265: 2262: 2259: 2256: 2253: 2233: 2209: 2187: 2182: 2178: 2157: 2154: 2151: 2129: 2125: 2121: 2118: 2096: 2091: 2088: 2068: 2065: 2062: 2059: 2056: 2053: 2050: 2047: 2044: 2041: 2038: 2035: 2032: 2029: 2026: 2023: 2018: 2015: 2011: 2007: 2004: 1978: 1974: 1951: 1929: 1926: 1923: 1920: 1917: 1897: 1877: 1872: 1868: 1864: 1861: 1858: 1838: 1829:finite, while 1816: 1794: 1789: 1784: 1781: 1778: 1756: 1752: 1729: 1725: 1704: 1684: 1664: 1659: 1655: 1651: 1648: 1645: 1623: 1619: 1595: 1592: 1580: 1577: 1575: 1572: 1571: 1570: 1569: 1568: 1557: 1552: 1547: 1544: 1541: 1536: 1532: 1528: 1523: 1519: 1496: 1491: 1488: 1485: 1480: 1476: 1472: 1467: 1463: 1459: 1454: 1450: 1444: 1439: 1436: 1433: 1429: 1418: 1414: 1403: 1398: 1393: 1390: 1387: 1382: 1378: 1374: 1369: 1365: 1342: 1337: 1334: 1331: 1326: 1322: 1318: 1313: 1309: 1305: 1300: 1296: 1290: 1285: 1282: 1279: 1275: 1264: 1232: 1206: 1201: 1196: 1193: 1190: 1168: 1165: 1135: 1109: 1087: 1063: 1058: 1055: 1035: 1005: 992: 991: 990: 989: 978: 973: 968: 963: 959: 955: 952: 949: 944: 940: 931: 928: 925: 915: 910: 905: 901: 897: 894: 891: 886: 882: 871: 867: 856: 851: 846: 841: 837: 833: 830: 827: 822: 818: 809: 806: 803: 793: 788: 783: 779: 775: 772: 769: 764: 760: 749: 745: 734: 729: 724: 721: 718: 715: 705: 700: 697: 694: 691: 681: 674: 663: 658: 653: 650: 647: 644: 634: 629: 626: 623: 620: 610: 600: 599: 598: 587: 582: 577: 574: 552: 547: 542: 539: 529: 517: 501: 490: 485: 480: 477: 467: 462: 459: 456: 453: 443: 432: 402: 399: 377: 374: 348: 323: 300: 295: 290: 287: 284: 272: 269: 245: 202: 199: 170: 148: 122: 97: 74: 69: 64: 61: 58: 33: 9: 6: 4: 3: 2: 7733: 7722: 7719: 7717: 7714: 7713: 7711: 7700: 7686: 7680: 7629: 7626: 7621: 7617: 7613: 7608: 7604: 7600: 7597: 7594: 7591: 7571: 7556: 7540: 7526: 7524: 7521: 7505: 7490: 7474: 7468: 7460: 7453: 7451: 7448: 7443: 7439: 7431: 7415: 7405: 7379: 7370: 7366:intersections 7361: 7333: 7324: 7315: 7311:intersections 7306: 7303: 7297: 7293: 7292:closed under: 7249: 7232: 7231: 7190: 7179: 7138: 7133: 7132: 7098: 7087: 7039: 7037:Open Topology 7034: 7033: 7004: 7001: 6944: 6939: 6938: 6909: 6906: 6849: 6847:(Filter base) 6841: 6840: 6811: 6808: 6751: 6746: 6745: 6672: 6667: 6666: 6597: 6589: 6588: 6519: 6511: 6510: 6441: 6436: 6435: 6366: 6361: 6360: 6291: 6283: 6282: 6209: 6201: 6200: 6180: 6157: 6153: 6116: 6113: 6110: 6078: 6068: 6067: 6026: 6022: 5994: 5990: 5944: 5939: 5938: 5868: 5859: 5858: 5788: 5784: 5783: 5709: 5702: 5701: 5697: 5693: 5671: 5668: 5660: 5638: 5627: 5612: 5609: 5604: 5600: 5596: 5591: 5587: 5578: 5563: 5560: 5555: 5551: 5547: 5542: 5538: 5529: 5514: 5500: 5485: 5479: 5471: 5456: 5453: 5450: 5442: 5427: 5424: 5421: 5413: 5410: 5397: 5384: 5380: 5379:closed under: 5336: 5319: 5318: 5312: 5307: 5305: 5300: 5298: 5293: 5292: 5269: 5240: 5234: 5231: 5227: 5223: 5222: 5217: 5213: 5212: 5203: 5199: 5196: 5192: 5188: 5186:0-521-33779-8 5182: 5178: 5174: 5170: 5167: 5163: 5160: 5156: 5155:Goldblatt, R. 5153: 5152: 5140: 5134: 5130: 5118: 5115: 5112: 5111:Stone duality 5109: 5106: 5103: 5100: 5097: 5094: 5091: 5088: 5085: 5082: 5079: 5076: 5073: 5067: 5064: 5061: 5055: 5046: 5043: 5037: 5034: 5032: 5029: 5026: 5023: 5020: 5017: 5015: 5014:General frame 5012: 5009: 5003: 4997: 4994: 4991: 4988: 4982: 4979: 4978: 4971: 4969: 4965: 4961: 4957: 4952: 4950: 4945: 4943: 4942:power algebra 4939: 4888: 4856: 4852: 4847: 4833: 4826: 4823: 4818: 4814: 4810: 4807: 4804: 4799: 4795: 4786: 4782: 4771: 4767: 4763: 4758: 4754: 4750: 4747: 4744: 4739: 4735: 4731: 4726: 4722: 4713: 4710: 4707: 4704: 4700: 4696: 4688: 4684: 4680: 4677: 4674: 4669: 4665: 4656: 4652: 4625: 4620: 4616: 4612: 4609: 4606: 4601: 4597: 4576: 4554: 4550: 4529: 4526: 4523: 4520: 4498: 4494: 4473: 4470: 4467: 4464: 4439: 4429: 4425: 4418: 4415: 4412: 4406: 4400: 4397: 4394: 4391: 4388: 4375: 4327: 4322: 4317: 4312: 4308: 4304: 4299: 4296: 4290: 4277: 4273: 4247: 4244: 4233: 4229: 4208: 4198: 4194: 4187: 4184: 4151: 4146: 4136: 4132: 4125: 4122: 4111: 4101: 4099: 4094: 4090: 4086: 4082: 4078: 4073: 4071: 4055: 4052: 4049: 4029: 4026: 4023: 3996: 3993: 3973: 3970: 3967: 3935: 3931: 3921: 3919: 3915: 3911: 3907: 3903: 3898: 3882: 3879: 3876: 3868: 3865: 3862: 3854: 3851: 3848: 3845: 3839: 3833: 3799: 3796: 3793: 3785: 3782: 3779: 3771: 3768: 3765: 3762: 3756: 3750: 3709: 3706: 3698: 3692: 3668: 3665: 3654: 3635: 3632: 3629: 3596: 3593: 3590: 3587: 3576: 3566: 3563: 3559: 3555: 3554:open elements 3550: 3545: 3541: 3539: 3529: 3526: 3521: 3519: 3515: 3510: 3504: 3502: 3498: 3494: 3490: 3487: 3483: 3479: 3474: 3461: 3448: 3445: 3434: 3406: 3378: 3352: 3349: 3338: 3312: 3309: 3276: 3266: 3263: 3252: 3242: 3240: 3236: 3232: 3227: 3225: 3221: 3217: 3213: 3209: 3208:sample points 3205: 3201: 3197: 3194:is in fact a 3181: 3173: 3157: 3127: 3124: 3098: 3095: 3085: 3082: 3071: 3070:measure space 3066: 3064: 3060: 3056: 3052: 3048: 3044: 3043:sigma algebra 3040: 3039:intersections 3037: 3033: 3018: 3016: 3012: 3011:Stone duality 3008: 3000: 2951: 2947: 2946:Boolean space 2920: 2913: 2864: 2863:compact space 2837: 2830: 2805: 2778: 2771: 2768: 2741: 2734: 2733: 2732: 2684: 2681: 2647: 2639: 2613: 2610: 2604: 2590: 2570: 2562: 2558: 2554: 2551: 2547: 2543: 2542: 2536: 2534: 2529: 2528:homomorphisms 2524: 2522: 2521:Dedekind cuts 2519:, similar to 2518: 2514: 2510: 2506: 2502: 2497: 2491: 2489: 2486: 2482: 2478: 2474: 2469: 2455: 2447: 2431: 2411: 2402: 2388: 2368: 2341: 2338: 2318: 2315: 2312: 2292: 2289: 2286: 2266: 2263: 2257: 2251: 2231: 2223: 2207: 2198: 2185: 2180: 2176: 2155: 2152: 2149: 2127: 2123: 2119: 2116: 2089: 2086: 2063: 2060: 2054: 2048: 2045: 2042: 2039: 2036: 2030: 2024: 2016: 2013: 2009: 2005: 2002: 1994: 1993:inverse image 1976: 1972: 1927: 1921: 1918: 1915: 1895: 1870: 1866: 1862: 1859: 1836: 1782: 1779: 1754: 1750: 1727: 1723: 1702: 1682: 1657: 1653: 1649: 1646: 1621: 1617: 1609: 1593: 1590: 1555: 1545: 1542: 1539: 1534: 1530: 1526: 1521: 1517: 1489: 1486: 1483: 1478: 1474: 1470: 1465: 1461: 1457: 1452: 1448: 1437: 1434: 1431: 1427: 1416: 1415: 1401: 1391: 1388: 1385: 1380: 1376: 1372: 1367: 1363: 1335: 1332: 1329: 1324: 1320: 1316: 1311: 1307: 1303: 1298: 1294: 1283: 1280: 1277: 1273: 1262: 1259:Closed under 1258: 1257: 1256: 1254: 1252: 1250: 1249: 1220: 1194: 1191: 1179: 1166: 1163: 1155: 1151: 1123: 1107: 1056: 1053: 1033: 1025: 1021: 976: 966: 961: 957: 953: 950: 947: 942: 938: 929: 926: 923: 908: 903: 899: 895: 892: 889: 884: 880: 869: 868: 854: 844: 839: 835: 831: 828: 825: 820: 816: 807: 804: 801: 786: 781: 777: 773: 770: 767: 762: 758: 747: 746: 732: 722: 719: 716: 713: 698: 695: 692: 689: 680: 679:intersections 676: 675: 661: 651: 648: 645: 642: 627: 624: 621: 618: 609: 605: 604: 603: 601: 585: 575: 572: 564: 563: 550: 540: 537: 515: 508:(or contains 507: 504:Contains the 503: 502: 488: 478: 475: 460: 457: 451: 430: 422: 419:Closed under 418: 417: 416: 415: 413: 400: 397: 390:algebra over 375: 372: 364: 337: 321: 314: 288: 285: 268: 266: 261: 259: 243: 235: 231: 227: 222: 220: 219:intersections 217:, and finite 216: 200: 197: 189: 185: 181: 168: 161:algebra over 146: 138: 111: 95: 88: 62: 59: 48: 44: 43:field of sets 40: 30: 19: 7520: 7447: 7445: 7436:Intersection 6512: 5219: 5201: 5194: 5177:Stone spaces 5176: 5165: 5158: 5133: 5087:Set function 5081:Ring of sets 4996:Boolean ring 4967: 4964:group theory 4955: 4953: 4946: 4941: 4937: 4936:is called a 4853:having both 4848: 4589:and for all 4275: 4271: 4107: 4097: 4088: 4076: 4074: 4069: 3933: 3929: 3927: 3909: 3901: 3899: 3693: 3577:is a triple 3574: 3572: 3561: 3557: 3549:Stone fields 3548: 3546: 3542: 3537: 3535: 3522: 3505: 3488: 3475: 3253:is a triple 3250: 3248: 3228: 3216:sample space 3215: 3211: 3207: 3204:sample space 3203: 3199: 3072:is a triple 3069: 3067: 3062: 3050: 3046: 3029: 3004: 2998: 2765:is always a 2586: 2556: 2549: 2545: 2533:truth tables 2525: 2509:order theory 2500: 2496:ultrafilters 2492: 2480: 2470: 2446:quotient set 2403: 2305:for a point 2199: 1888:with finite 1582: 1246: 1245:is called a 1218: 1217:is called a 1180: 1153: 1149: 1121: 993: 389: 274: 262: 223: 160: 42: 36: 7557:of sets in 7523:semialgebra 7491:of sets in 7336:complements 7329:complements 5866:(Semifield) 5863:Semialgebra 5099:Sigma-ideal 3486:modal logic 3007:Stone space 2999:descriptive 2950:clopen sets 2911:is compact. 1148:are called 1120:are called 271:Definitions 230:ring theory 188:complements 39:mathematics 18:Set algebra 7710:Categories 6670:Dual ideal 6595:(𝜎-Field) 6592:𝜎-Algebra 5149:References 4949:isomorphic 2546:separative 2142:(that is, 1020:subalgebra 388:called an 159:called an 7684:∅ 7681:≠ 7630:… 7538:∖ 7535:Ω 7472:∖ 7416:∅ 7408:contains 7390:Ω 7382:contains 7373:countable 7364:countable 7346:Ω 7250:: 7191:∩ 7099:∪ 7002:∅ 6907:∅ 6844:Prefilter 6809:∅ 6177:they are 6163:↗ 6114:⊆ 6071:𝜆-system 6032:↗ 6000:↘ 5672:∈ 5669:∅ 5639:∈ 5636:Ω 5613:⋯ 5610:∪ 5597:∪ 5564:⋯ 5561:∩ 5548:∩ 5512:∖ 5509:Ω 5483:∖ 5454:∪ 5425:∩ 5398:⊇ 5337:: 5278:Ω 5244:Families 5226:EMS Press 5093:σ-algebra 4855:operators 4808:… 4764:∈ 4748:… 4732:∈ 4708:∈ 4678:… 4626:∈ 4610:… 4468:∈ 4410:∅ 4404:′ 4398:∪ 4392:∩ 4232:relations 4077:canonical 4053:∈ 4027:∈ 3997:∈ 3971:≤ 3930:algebraic 3880:≤ 3866:∈ 3849:∈ 3797:≤ 3783:∈ 3766:∈ 3710:∈ 3636:≤ 3594:≤ 3538:algebraic 3501:semantics 3182:μ 3158:μ 3099:μ 3036:countable 2511:based on 2342:∈ 2316:∈ 2290:∈ 2279:whenever 2153:⊂ 2120:∈ 2090:∈ 2061:∈ 2046:∣ 2040:∈ 2014:− 1925:→ 1608:power set 1546:∈ 1543:… 1490:∈ 1487:⋯ 1484:∩ 1471:∩ 1443:∞ 1428:⋂ 1392:∈ 1389:… 1336:∈ 1333:⋯ 1330:∪ 1317:∪ 1289:∞ 1274:⋃ 1261:countable 1248:σ-algebra 1150:complexes 1057:∈ 967:∈ 951:… 927:≥ 909:∈ 896:∩ 893:⋯ 890:∩ 845:∈ 829:… 805:≥ 787:∈ 774:∪ 771:⋯ 768:∪ 723:∈ 699:∈ 693:∩ 652:∈ 628:∈ 622:∪ 576:∈ 541:∈ 538:∅ 506:empty set 479:∈ 461:∈ 455:∖ 232:nor with 184:empty set 7450:semiring 7438:Property 7327:relative 7302:downward 7300:directed 7005:∉ 6910:∉ 6812:∉ 6514:Algebra 6179:disjoint 6145:only if 6014:only if 5982:only if 5787:Semiring 5387:Directed 5175:(1982). 4974:See also 4042:implies 3484:for the 3059:Sikorski 2589:topology 2485:complete 1509:for all 1355:for all 1018:forms a 7459:-system 7267:or, is 6516:(Field) 6439:𝜎-Ring 6102:only if 5708:-system 5354:or, is 5268:of sets 5228:, 2001 5105:𝜎-ring 5060:-system 4968:complex 4956:complex 3904:in the 3231:Physics 3172:measure 3015:duality 2557:compact 2517:filters 363:subsets 213:finite 137:subsets 7434:Finite 7375:unions 7320:unions 7318:finite 7309:finite 7228:Never 7129:Never 6749:Filter 6663:Never 6585:Never 6507:Never 6432:Never 6364:δ-Ring 6357:Never 6197:Never 5935:Never 5855:Never 5696:F.I.P. 5183:  5006:δ 4174:where 3619:where 3525:clopen 3507:Every 3495:) and 3299:where 3212:events 3114:where 3055:Loomis 3053:. The 3032:unions 2707:where 2561:filter 2513:ideals 2488:atomic 2448:; and 2079:where 1263:unions 1122:points 608:unions 336:family 334:and a 226:fields 215:unions 110:family 108:and a 7454:is a 6971:Never 6968:Never 6876:Never 6873:Never 6778:Never 6775:Never 6286:Ring 6204:Ring 5270:over 5125:Notes 5008:-ring 4960:group 4901:then 4542:then 4226:is a 3934:tight 3651:is a 3335:is a 3170:is a 2948:with 2944:is a 2861:is a 2802:is a 2563:over 2477:atoms 2222:atoms 1805:with 45:is a 5181:ISBN 4274:(or 3932:(or 3815:and 3655:and 3339:and 3222:and 2638:base 2548:(or 2109:and 1991:via 1964:and 1606:its 41:, a 7338:in 5389:by 4970:.) 4940:or 4486:if 3516:of 3435:on 3379:of 3237:or 2515:or 2244:by 1419:: 1265:: 1156:of 1026:of 872:: 750:: 682:: 611:: 423:in 365:of 361:of 313:set 228:in 190:in 139:of 135:of 87:set 37:In 7712:: 7519:A 6175:or 5224:, 5218:, 5157:, 4944:. 4098:S4 4070:S4 4016:, 3910:S4 3729:: 3573:A 3520:. 3489:S4 3249:A 3068:A 2535:. 2523:. 2424:; 1995:: 1458::= 1304::= 444:: 221:. 7687:. 7676:F 7652:F 7627:, 7622:2 7618:A 7614:, 7609:1 7605:A 7601:, 7598:B 7595:, 7592:A 7572:. 7567:F 7541:A 7506:. 7501:F 7475:A 7469:B 7457:π 7277:F 7245:F 7203:) 7111:) 7010:F 6915:F 6817:F 6158:i 6154:A 6117:B 6111:A 6027:i 6023:A 5995:i 5991:A 5706:π 5677:F 5644:F 5605:2 5601:A 5592:1 5588:A 5556:2 5552:A 5543:1 5539:A 5515:A 5486:A 5480:B 5457:B 5451:A 5428:B 5422:A 5364:F 5332:F 5310:e 5303:t 5296:v 5254:F 5189:. 5058:π 4924:) 4920:X 4916:( 4911:C 4889:X 4867:F 4834:} 4830:) 4827:x 4824:, 4819:n 4815:x 4811:, 4805:, 4800:1 4796:x 4792:( 4787:i 4783:R 4772:n 4768:S 4759:n 4755:x 4751:, 4745:, 4740:1 4736:S 4727:1 4723:x 4714:: 4711:X 4705:x 4701:{ 4697:= 4694:) 4689:n 4685:S 4681:, 4675:, 4670:1 4666:S 4662:( 4657:i 4653:f 4631:F 4621:n 4617:S 4613:, 4607:, 4602:1 4598:S 4577:n 4555:i 4551:f 4530:, 4527:1 4524:+ 4521:n 4499:i 4495:R 4474:, 4471:I 4465:i 4445:) 4440:I 4436:) 4430:i 4426:f 4422:( 4419:, 4416:X 4413:, 4407:, 4401:, 4395:, 4389:, 4384:F 4379:( 4376:= 4373:) 4369:X 4365:( 4360:C 4338:) 4333:F 4328:, 4323:I 4318:) 4313:i 4309:R 4305:( 4300:, 4297:X 4294:( 4291:= 4287:X 4258:) 4253:F 4248:, 4245:X 4242:( 4214:) 4209:I 4205:) 4199:i 4195:R 4191:( 4188:, 4185:X 4182:( 4162:) 4157:F 4152:, 4147:I 4143:) 4137:i 4133:R 4129:( 4126:, 4123:X 4120:( 4056:S 4050:y 4030:S 4024:x 4002:A 3994:S 3974:y 3968:x 3946:A 3886:} 3883:y 3877:x 3869:S 3863:y 3855:: 3852:X 3846:x 3843:{ 3840:= 3837:) 3834:S 3831:( 3827:l 3824:C 3803:} 3800:x 3794:y 3786:S 3780:y 3772:: 3769:X 3763:x 3760:{ 3757:= 3754:) 3751:S 3748:( 3744:t 3741:n 3738:I 3715:F 3707:S 3679:) 3674:F 3669:, 3666:X 3663:( 3639:) 3633:, 3630:X 3627:( 3607:) 3602:F 3597:, 3591:, 3588:X 3585:( 3462:. 3459:) 3454:T 3449:, 3446:X 3443:( 3417:F 3389:T 3363:) 3358:F 3353:, 3350:X 3347:( 3323:) 3318:T 3313:, 3310:X 3307:( 3287:) 3282:F 3277:, 3272:T 3267:, 3264:X 3261:( 3138:) 3133:F 3128:, 3125:X 3122:( 3102:) 3096:, 3091:F 3086:, 3083:X 3080:( 3057:- 3001:) 2984:X 2961:F 2932:) 2928:X 2924:( 2921:T 2898:X 2875:F 2849:) 2845:X 2841:( 2838:T 2815:X 2790:) 2786:X 2782:( 2779:T 2769:. 2753:) 2749:X 2745:( 2742:T 2717:T 2695:) 2690:T 2685:, 2682:X 2679:( 2659:) 2655:X 2651:( 2648:T 2624:) 2619:F 2614:, 2611:X 2608:( 2605:= 2601:X 2571:X 2456:f 2432:Y 2412:X 2389:A 2369:A 2347:F 2339:A 2319:X 2313:x 2293:A 2287:x 2267:A 2264:= 2261:) 2258:x 2255:( 2252:f 2232:f 2208:Y 2186:. 2181:n 2177:2 2156:Y 2150:B 2128:Y 2124:2 2117:B 2095:F 2087:S 2067:} 2064:B 2058:) 2055:x 2052:( 2049:f 2043:X 2037:x 2034:{ 2031:= 2028:] 2025:B 2022:[ 2017:1 2010:f 2006:= 2003:S 1977:Y 1973:2 1950:F 1928:Y 1922:X 1919:: 1916:f 1896:Y 1876:) 1871:Y 1867:2 1863:, 1860:Y 1857:( 1837:X 1815:F 1793:) 1788:F 1783:, 1780:X 1777:( 1755:n 1751:2 1728:Y 1724:2 1703:n 1683:Y 1663:) 1658:Y 1654:2 1650:, 1647:Y 1644:( 1622:Y 1618:2 1594:, 1591:Y 1556:. 1551:F 1540:, 1535:2 1531:F 1527:, 1522:1 1518:F 1495:F 1479:2 1475:F 1466:1 1462:F 1453:i 1449:F 1438:1 1435:= 1432:i 1402:. 1397:F 1386:, 1381:2 1377:F 1373:, 1368:1 1364:F 1341:F 1325:2 1321:F 1312:1 1308:F 1299:i 1295:F 1284:1 1281:= 1278:i 1231:F 1205:) 1200:F 1195:, 1192:X 1189:( 1167:. 1164:X 1134:F 1108:X 1086:F 1062:F 1054:X 1034:X 1004:F 977:. 972:F 962:n 958:F 954:, 948:, 943:1 939:F 930:1 924:n 914:F 904:n 900:F 885:1 881:F 855:. 850:F 840:n 836:F 832:, 826:, 821:1 817:F 808:1 802:n 792:F 782:n 778:F 763:1 759:F 733:. 728:F 720:G 717:, 714:F 704:F 696:G 690:F 662:. 657:F 649:G 646:, 643:F 633:F 625:G 619:F 586:. 581:F 573:X 551:. 546:F 528:) 516:X 489:. 484:F 476:F 466:F 458:F 452:X 431:X 401:, 398:X 376:, 373:X 347:F 322:X 299:) 294:F 289:, 286:X 283:( 244:X 201:, 198:X 169:X 147:X 121:F 96:X 73:) 68:F 63:, 60:X 57:( 31:. 20:)

Index

Set algebra
Algebra of sets
mathematics
mathematical structure
set
family
subsets
empty set
complements
unions
intersections
fields
ring theory
fields in physics
algebras over fields or rings
representation theory
set
family
subsets
complementation
empty set
unions
intersections
subalgebra
Boolean algebra
σ-algebra
countable
power set
inverse image
atoms

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