Knowledge

Construction of the real numbers

Source πŸ“

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We shall not prove that any models of the axioms are isomorphic. Such a proof can be found in any number of modern analysis or set theory textbooks. We will sketch the basic definitions and properties of a number of constructions, however, because each of these is important for both mathematical and
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is finite. This defines an equivalence relation on the set of almost homomorphisms. Real numbers are defined as the equivalence classes of this relation. Alternatively, the almost homomorphisms taking only finitely many values form a subgroup, and the underlying additive group of the real number is
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between them. This results from the above definition and is independent of particular constructions. These isomorphisms allow identifying the results of the constructions, and, in practice, to forget which construction has been chosen.
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write: "Few mathematical structures have undergone as many revisions or have been presented in as many guises as the real numbers. Every generation reexamines the reals in the light of its values and mathematical objectives."
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the quotient group. To add real numbers defined this way we add the almost homomorphisms that represent them. Multiplication of real numbers corresponds to functional composition of almost homomorphisms. If
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Normally, metrics are defined with real numbers as values, but this does not make the construction/definition circular, since all numbers that are implied (even implicitly) are rational numbers.
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that does not contain any smaller complete ordered field. Such a definition does not prove that such a complete ordered field exists, and the existence proof consists of constructing a
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An advantage of this construction is that each real number corresponds to a unique cut. Furthermore, by relaxing the first two requirements of the definition of a cut, the
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all occurred within a few years of each other. Each has advantages and disadvantages. A major motivation in all three cases was the instruction of mathematics students.
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The article presents several such constructions. They are equivalent in the sense that, given the result of any two such constructions, there is a unique
6986: 6325:(meaning that no real number is infinitely large or infinitely small). This embedding is not unique, though it can be chosen in a canonical way. 6271:
of real numbers. This construction uses a non-principal ultrafilter over the set of natural numbers, the existence of which is guaranteed by the
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satisfies the first three axioms, but not the fourth. In other words, models of the rational numbers are also models of the first three axioms.
6309:. Hence the resulting field is an ordered field. Completeness can be proved in a similar way to the construction from the Cauchy sequences. 5094: 4388: 56:
of the real numbers consists of defining them as the elements of a complete ordered field. This means the following: The real numbers form a
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is represented by a Cauchy sequence of rational numbers. This representation is far from unique; every rational sequence that converges to
5484: 6898: 1168:, as it expresses a statement about collections of reals and not just individual such numbers. As such, the reals are not given by a 1305: 1687: 6433: 7645: 7597: 7506: 7456: 7398: 4550: 1295:{\displaystyle (\mathbb {R} ,0_{\mathbb {R} },1_{\mathbb {R} },+_{\mathbb {R} },\times _{\mathbb {R} },\leq _{\mathbb {R} })} 4193: 152:
an isomorphism, and thus, the real numbers can be used and manipulated, without referring to the method of construction.
6999: 4845:{\displaystyle A\times B:=\{a\times b:a\geq 0\land a\in A\land b\geq 0\land b\in B\}\cup \{x\in \mathrm {Q} :x<0\}} 2190:"If a set of reals precedes another set of reals, then there exists at least one real number separating the two sets." 7165: 6971: 6626: 5226: 4315: 6397: 6994: 6889:
As a reviewer of one noted: "The details are all included, but as usual they are tedious and not too instructive."
6524: 4257: 4306:, such a set can have no greatest element and thus fulfills the conditions for being a real number laid out above. 7435:
Knopfmacher, Arnold; Knopfmacher, John (1987). "A new construction of the real numbers (via infinite products)".
5052: 148:, which is proved by constructing such a structure. A consequence of the axioms is that this structure is unique 3024:. This reflects the observation that one can often use different sequences to approximate the same real number. 6947: 1402: 6963: 4472: 6593:.) Almost homomorphisms form an abelian group under pointwise addition. We say that two almost homomorphisms 6568: 6380: 6333:
A relatively less known construction allows to define real numbers using only the additive group of integers
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Comparison between real numbers is obtained by defining the following comparison between Cauchy sequences:
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The only real number axiom that does not follow easily from the definitions is the completeness of
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if and only if the difference between them tends to zero; that is, for every rational number
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The axiom is crucial in the characterization of the reals. For example, the totally
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can be translated to Cauchy sequences in a natural way. For example, the notation
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Addition and multiplication are compatible with the order. In other words,
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to converge is adding new points to the metric space in a process called
1891: 1079: 1038: 888: 36: 21: 17: 5172:{\displaystyle A/B:=\{a/b:a\in A\land b\in ({\textbf {Q}}\setminus B)\}} 4462:{\displaystyle A-B:=\{a-b:a\in A\land b\in ({\textbf {Q}}\setminus B)\}} 3684:. Real numbers can be constructed as Dedekind cuts of rational numbers. 3315:
This defines two Cauchy sequences of rationals, and so the real numbers
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Saying that any two models are isomorphic means that for any two models
7553: 7520:"A new approach to the real numbers (motivated by continued fractions)" 6387:
to give a Dedekind-complete ordered field by the IsarMathLib project.
4680:{\displaystyle -B:=\{a-b:a<0\land b\in ({\textbf {Q}}\setminus B)\}} 4234:
the rational numbers into the reals by identifying the rational number
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de Bruijn, N.G. (1977). "Construction of the system of real numbers".
7299: 7282: 4988:{\displaystyle A\times B=-(A\times -B)=-(-A\times B)=(-A\times -B)\,} 4231: 3628:
is that this construction can be used for every other metric spaces.
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became the basis for this construction. This construction has been
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that preserves both the field operations and the order. Explicitly,
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Abhandlungen der Braunschweigischen Wissenschaftlichen Gesellschaft
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Lectures on the Hyperreals: An introduction to nonstandard analysis
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that is compatible with the operations defined above, and the set
1192:. Any two models are isomorphic; so, the real numbers are unique 145: 6367:, naming them after ancient Greek astronomer and mathematician 7125:"Hyperreals and a Brief Introduction to Non-Standard Analysis" 6714:
denotes the real number represented by an almost homomorphism
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has no greatest element, i.e. that for any positive rational
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of rational numbers that fulfills the following conditions:
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of Cauchy sequences of rational numbers. That is, sequences
1389:{\displaystyle (S,0_{S},1_{S},+_{S},\times _{S},\leq _{S}),} 7411: 7334:
http://alexandria.tue.nl/repository/freearticles/597556.pdf
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contains no greatest element. In other words, there is no
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Faltin, F.; Metropolis, M.; Ross, B.; Rota, G.-C. (1975).
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relation on the set of real numbers constructed this way.
6359:, who attributes this construction to unpublished work by 6278:
It turns out that the maximal ideal respects the order on
3080:. Substituting a larger value if necessary, we may assume 1188:
that satisfies the above axioms. Several models are given
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to a positive number and then apply the definition above.
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Decidability of first-order theories of the real numbers
6847: 6514:{\displaystyle \{f(n+m)-f(m)-f(n):n,m\in \mathbb {Z} \}} 6379:, Eudoxus's treatment of quantity using the behavior of 6113:. Here a hyperrational is by definition a ratio of two 5037:
to positive numbers and then apply the definition above.
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Shenitzer, A (1987). "A topics course in mathematics".
7276:(2003). "A natural construction for the real numbers". 7194: 6903:
Pages displaying short descriptions of redirect targets
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Constructivism (mathematics)#Example from real analysis
6069: 4594:{\displaystyle \{x:x\in {\textbf {Q}}\land x\notin B\}} 1802:, denoted by the infix operator +, and the constant 1. 1681: 7449: 7434: 6876: 6872: 5066: 1696:
of the real numbers and their arithmetic was given by
7393:. New York: Oxford University Press US. p. 274. 7021: 6854:
A number of other constructions have been given, by:
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are equivalent, i.e., their difference converges to
2650:. Here the vertical bars denote the absolute value. 1137: 20:, there are several equivalent ways of defining the 7218: 6321:. The real numbers form a maximal subfield that is 4221:{\displaystyle x\leq y\Leftrightarrow x\subseteq y} 2536:of the rational numbers with respect to the metric 2444: 186:under addition and multiplication. In other words, 7490: 7206: 7182: 7094: 7092: 7090: 7088: 7086: 7029: 6827: 6798: 6778: 6758: 6726: 6706: 6679: 6611: 6585: 6557: 6513: 6422: 6347: 6301: 6263: 6238: 6206: 6183: 6163: 6132: 6101: 6058: 6034: 6014: 5984: 5951: 5931: 5910: 5883: 5862: 5830: 5777: 5741: 5714: 5693: 5660: 5639: 5619: 5598: 5565: 5545: 5461: 5438: 5414: 5390: 5362: 5341: 5320: 5215: 5194: 5171: 5083: 5029: 5008: 4987: 4888: 4867: 4844: 4720: 4679: 4593: 4539: 4515: 4491: 4461: 4372: 4294: 4246: 4220: 4178: 4154: 4134: 4106: 4080: 4054: 4028: 4007: 3981: 3955: 3929: 3893: 3872: 3840: 3817: 3793: 3773: 3753: 3733: 3700: 3620: 3598: 3060: 2914:with the equivalence class of the Cauchy sequence 2900: 2878: 2528: 2506: 2425: 2396: 2365: 2337: 2211: 2079: 2053: 1948: 1908: 1822: 1790: 1756: 1730: 1670: 1593: 1425: 1388: 1294: 1099: 1066: 1029: 1015:in the following sense: every non-empty subset of 982: 925: 863: 802: 737: 692: 663: 639: 605: 579: 538: 512: 475: 434: 373: 300: 215: 174: 125: 74: 7293:Arthan, R.D. (2004). "The Eudoxus Real Numbers". 7104: 5553:. It can be seen from the definitions above that 2598:of rational numbers such that for every rational 7632: 6920: 5473:As an example of a Dedekind cut representing an 4142:of real numbers as the set of all Dedekind cuts 3708:as the representative of any given Dedekind cut 3631: 3558:is the equivalence class of the Cauchy sequence 7450:Knopfmacher, Arnold; Knopfmacher, John (1988). 7083: 7047: 6806:takes an infinite number of positive values on 6680:{\displaystyle \{f(n)-g(n):n\in \mathbb {Z} \}} 5321:{\displaystyle A/B=-(A/{-B})=-(-A/B)=-A/{-B}\,} 4373:{\displaystyle A+B:=\{a+b:a\in A\land b\in B\}} 3901:is closed downwards. In other words, for all 3482:is monotonic increasing it is easy to see that 7148:Goldblatt, Robert (1998). "Exercise 5.7 (4)". 6423:{\displaystyle f:\mathbb {Z} \to \mathbb {Z} } 5870:but to show equality requires showing that if 3092:is non-empty, we can choose a rational number 98:of real numbers and denoted respectively with 7312:"Defining reals without the use of rationals" 6558:{\displaystyle f(n)=\lfloor \alpha n\rfloor } 4295:{\displaystyle \{x\in {\textbf {Q}}:x<q\}} 4254:with the set of all smaller rational numbers 2411:under addition with distinguished element 1. 2035:To clarify the above statement somewhat, let 7593:"The real numbers-a survey of constructions" 7343:Nederl. Akad. Wetensch. Verslag Afd. Natuurk 6674: 6630: 6552: 6543: 6508: 6437: 5540: 5494: 5166: 5112: 4839: 4813: 4807: 4747: 4674: 4622: 4588: 4554: 4456: 4404: 4367: 4331: 4289: 4261: 2450:historical reasons. The first three, due to 1006:(preservation of order under multiplication) 7272: 7200: 6317:Every ordered field can be embedded in the 5084:{\displaystyle A\geq 0{\mbox{ and }}B>0} 621:= 1. (existence of multiplicative inverses) 6329:Construction from integers (Eudoxus reals) 6218:hyperrational numbers. The quotient ring 3687:For convenience we may take the lower set 2861: 133:Moreover, the following properties called 7620: 7610: 7539: 7469: 7375: 7340: 7309: 7298: 7281: 7147: 7023: 6862: 6858: 6815: 6670: 6579: 6504: 6416: 6408: 6372: 6341: 6295: 6257: 6157: 6140:of all limited (i.e. finite) elements in 6109:from the rational numbers by means of an 6095: 5981: 5928: 5907: 5880: 5827: 5771: 5738: 5711: 5690: 5657: 5616: 5595: 5359: 5338: 5317: 5212: 5191: 5026: 5005: 4984: 4885: 4864: 3730: 3697: 3614: 3592: 3050: 2894: 2872: 2522: 2500: 2419: 2390: 2359: 2331: 2205: 2073: 2047: 1942: 1902: 1816: 1784: 1750: 1724: 1661: 1584: 1426:{\displaystyle f\colon \mathbb {R} \to S} 1413: 1283: 1268: 1253: 1238: 1223: 1210: 1090: 1060: 1023: 976: 919: 857: 796: 731: 686: 633: 599: 573: 532: 506: 469: 428: 367: 294: 209: 168: 68: 6961: 4492:{\displaystyle {\textbf {Q}}\setminus B} 3635: 2679:can be added and multiplied as follows: 2514:is defined as the completion of the set 1142:Axiom 4, which requires the order to be 957:. (preservation of order under addition) 491:. (existence of multiplicative identity) 47: 7409: 7316:Indagationes Mathematicae (Proceedings) 7224: 7122: 6586:{\displaystyle \alpha \in \mathbb {R} } 5831:{\displaystyle y={\frac {2x+2}{x+2}}\,} 5398:of real numbers has any upper bound in 3640:Dedekind used his cut to construct the 3347:. It is easy to prove, by induction on 7633: 7570: 7517: 7358:"The real numbers as a wreath product" 7292: 7255: 7212: 7188: 6867: 6842: 6376: 6356: 5999:system may be obtained by associating 3560:(3, 3.1, 3.14, 3.141, 3.1415, ...) 7598:Rocky Mountain Journal of Mathematics 7590: 7457:Rocky Mountain Journal of Mathematics 7386: 7110: 6964:"Interactive Notes for Real Analysis" 6926: 6883: 6363:, refers to this construction as the 5422:, then it has a least upper bound in 7488: 7420: 7098: 7053: 6962:Saunders, Bonnie (August 21, 2015). 6877:Knopfmacher & Knopfmacher (1988) 6873:Knopfmacher & Knopfmacher (1987) 6565:is an almost homomorphism for every 6078:, one constructs the hyperrationals 6070:Construction using hyperreal numbers 3930:{\displaystyle x,y\in {\textbf {Q}}} 3676:is nonempty and closed upwards, and 3120:. Now define sequences of rationals 2379:. 1 < 1 + 1. 1688:Tarski's axiomatization of the reals 1682:Tarski's axiomatization of the reals 7037:with respect to other metrics, see 6051: 5505: 5431: 5407: 5223:is negative, we use the identities 5152: 4896:is negative, we use the identities 4660: 4571: 4532: 4478: 4442: 4272: 4171: 4127: 3922: 3873:{\displaystyle r\neq {\textbf {Q}}} 3865: 3810: 3035:. It can be proved as follows: Let 3006:By construction, every real number 13: 6987:"Axioms of the Real Number System" 6029: 6009: 5481:. This can be defined by the set 4823: 4606:is a special case of subtraction: 3672:is nonempty and closed downwards, 3018:is a Cauchy sequence representing 2810:such that for all natural numbers 2611:such that for all natural numbers 2478:A standard procedure to force all 2474:Construction from Cauchy sequences 1115:, such that for every upper bound 24:. One of them is that they form a 14: 7657: 6972:University of Illinois at Chicago 6313:Construction from surreal numbers 5778:{\displaystyle y\times y<2\,.} 5349:to a non-negative number and/or 5157: 4665: 4483: 4447: 4302:. Since the rational numbers are 2908:by identifying a rational number 2886:can be considered as a subset of 1138:On the least upper bound property 520:, there exists an element − 457:0 is not equal to 1, and for all 7123:Krakoff, Gianni (June 8, 2015). 6995:University of California, Irvine 6828:{\displaystyle \mathbb {Z} ^{+}} 6302:{\displaystyle ^{*}\mathbb {Q} } 6164:{\displaystyle ^{*}\mathbb {Q} } 6102:{\displaystyle ^{*}\mathbb {Q} } 5985:{\displaystyle r<x\times x\,} 5694:{\displaystyle x\times x<2\,} 4190:on the real numbers as follows: 2445:Explicit constructions of models 413:of multiplication over addition) 7573:"Update on the efficient reals" 7571:Street, Ross (September 2003). 7497:. New York: Springer. pp.  7265: 7242: 7141: 7116: 5863:{\displaystyle A\times A\leq 2} 2186:Axiom 3 can then be stated as: 344:of addition and multiplication) 275:of addition and multiplication) 32:that satisfies the definition. 7542:The Mathematical Intelligencer 7489:Pugh, Charles Chapman (2002). 7071: 7059: 7009: 6979: 6955: 6948:University of Colorado Boulder 6932: 6753: 6747: 6701: 6695: 6657: 6651: 6642: 6636: 6537: 6531: 6485: 6479: 6470: 6464: 6455: 6443: 6412: 5627:is real requires showing that 5292: 5275: 5266: 5247: 5163: 5147: 4981: 4963: 4957: 4942: 4933: 4918: 4671: 4655: 4453: 4437: 4206: 3727: 3715: 2862:all axioms of the real numbers 1417: 1380: 1309: 1289: 1206: 554:) = 0. (existence of additive 1: 7518:Rieger, Georg Johann (1982). 6913: 6059:{\displaystyle {\textbf {Q}}} 5599:{\displaystyle A\times A=2\,} 5439:{\displaystyle {\textbf {R}}} 5415:{\displaystyle {\textbf {R}}} 4540:{\displaystyle {\textbf {Q}}} 4179:{\displaystyle {\textbf {Q}}} 4135:{\displaystyle {\textbf {R}}} 3818:{\displaystyle {\textbf {Q}}} 3632:Construction by Dedekind cuts 3584:An advantage of constructing 3463:is a smaller upper bound for 3061:{\displaystyle \mathbb {R} '} 1671:{\displaystyle \mathbb {R} .} 1594:{\displaystyle \mathbb {R} .} 1100:{\displaystyle \mathbb {R} ,} 7646:Constructivism (mathematics) 7423:"Cauchy's construction of R" 7390:What is Mathematics, Really? 7377:10.1016/0001-8708(75)90115-2 7328:10.1016/1385-7258(76)90055-X 7030:{\displaystyle \mathbb {Q} } 6348:{\displaystyle \mathbb {Z} } 6264:{\displaystyle \mathbb {R} } 5891:is any rational number with 3621:{\displaystyle \mathbb {Q} } 3599:{\displaystyle \mathbb {R} } 3571:(0, 0.9, 0.99, 0.999,...) 3387:is never an upper bound for 2901:{\displaystyle \mathbb {R} } 2879:{\displaystyle \mathbb {Q} } 2529:{\displaystyle \mathbb {Q} } 2507:{\displaystyle \mathbb {R} } 2426:{\displaystyle \mathbb {R} } 2397:{\displaystyle \mathbb {R} } 2366:{\displaystyle \mathbb {R} } 2338:{\displaystyle \mathbb {R} } 2212:{\displaystyle \mathbb {R} } 2080:{\displaystyle \mathbb {R} } 2054:{\displaystyle \mathbb {R} } 1949:{\displaystyle \mathbb {R} } 1909:{\displaystyle \mathbb {R} } 1890:. In other words, "<" is 1823:{\displaystyle \mathbb {R} } 1791:{\displaystyle \mathbb {R} } 1757:{\displaystyle \mathbb {R} } 1731:{\displaystyle \mathbb {R} } 1704:shown below and a mere four 1175: 1067:{\displaystyle \mathbb {R} } 1030:{\displaystyle \mathbb {R} } 983:{\displaystyle \mathbb {R} } 926:{\displaystyle \mathbb {R} } 864:{\displaystyle \mathbb {R} } 803:{\displaystyle \mathbb {R} } 738:{\displaystyle \mathbb {R} } 693:{\displaystyle \mathbb {R} } 640:{\displaystyle \mathbb {R} } 606:{\displaystyle \mathbb {R} } 580:{\displaystyle \mathbb {R} } 539:{\displaystyle \mathbb {R} } 513:{\displaystyle \mathbb {R} } 476:{\displaystyle \mathbb {R} } 435:{\displaystyle \mathbb {R} } 374:{\displaystyle \mathbb {R} } 301:{\displaystyle \mathbb {R} } 216:{\displaystyle \mathbb {R} } 175:{\displaystyle \mathbb {R} } 90:; the operations are called 75:{\displaystyle \mathbb {R} } 7: 7132:Department of Mathematics, 6892: 5573:is a real number, and that 3530:is a least upper bound for 2967:or there exists an integer 1700:, consisting of only the 8 10: 7662: 7493:Real Mathematical Analysis 6355:with different versions. 3569:states that the sequences 3514:is not an upper bound for 3033:least upper bound property 2804:, there exists an integer 2605:, there exists an integer 1685: 587:, there exists an element 7622:10.1216/RMJ-2015-45-3-737 7471:10.1216/RMJ-1988-18-4-813 7158:10.1007/978-1-4612-0615-6 5918:, then there is positive 5479:positive square root of 2 5462:{\displaystyle \bigcup S} 4721:{\displaystyle A,B\geq 0} 4693:is less straightforward. 3801:is any subset of the set 3656:in an ordered field is a 3041:be a non-empty subset of 2134:if and only if for every 2094:if and only if for every 1926:. More formally, for all 1692:An alternative synthetic 1052:is a non-empty subset of 450:. (existence of additive 155: 106:; the binary relation is 7310:de Bruijn, N.G. (1976). 7134:University of Washington 6015:{\displaystyle -\infty } 5911:{\displaystyle r<2\,} 5742:{\displaystyle x<y\,} 2860:can be shown to satisfy 2382:These axioms imply that 1852:. That is, "<" is an 1170:first-order logic theory 1157:of the rational numbers 1111:has a least upper bound 140:The existence of such a 7363:Advances in Mathematics 6035:{\displaystyle \infty } 6022:with the empty set and 4107:{\displaystyle y\leq x} 3734:{\displaystyle (A,B)\,} 1164:Note that the axiom is 7387:Hersh, Reuben (1997). 7254:(84j:26002) review of 7031: 6829: 6800: 6780: 6760: 6759:{\displaystyle 0\leq } 6728: 6708: 6681: 6613: 6587: 6559: 6521:is finite. (Note that 6515: 6424: 6349: 6303: 6265: 6240: 6208: 6185: 6165: 6134: 6103: 6060: 6036: 6016: 5986: 5953: 5933: 5912: 5885: 5864: 5832: 5779: 5743: 5716: 5701:, there is a rational 5695: 5662: 5641: 5621: 5600: 5567: 5547: 5463: 5440: 5416: 5392: 5364: 5343: 5322: 5217: 5196: 5173: 5085: 5031: 5010: 4989: 4890: 4869: 4846: 4722: 4681: 4595: 4541: 4517: 4493: 4463: 4374: 4296: 4248: 4222: 4180: 4156: 4136: 4108: 4082: 4081:{\displaystyle y\in r} 4056: 4055:{\displaystyle x\in r} 4030: 4009: 4008:{\displaystyle x\in r} 3983: 3982:{\displaystyle y\in r} 3957: 3956:{\displaystyle x<y} 3931: 3895: 3874: 3842: 3819: 3795: 3775: 3761:completely determines 3755: 3735: 3702: 3649: 3622: 3600: 3407:is an upper bound for 3364:is an upper bound for 3222:is an upper bound for 3074:be an upper bound for 3062: 2902: 2880: 2530: 2508: 2427: 2398: 2367: 2339: 2213: 2081: 2055: 1980:, then there exists a 1950: 1910: 1824: 1792: 1758: 1732: 1672: 1595: 1427: 1390: 1296: 1186:mathematical structure 1101: 1068: 1031: 984: 927: 865: 804: 739: 694: 665: 641: 607: 581: 540: 514: 477: 436: 375: 302: 217: 176: 127: 126:{\displaystyle \leq .} 76: 30:mathematical structure 26:complete ordered field 7591:Weiss, Ittay (2015). 7032: 7005:on December 26, 2010. 6882:For an overview, see 6830: 6801: 6781: 6761: 6729: 6709: 6682: 6614: 6588: 6560: 6516: 6425: 6350: 6304: 6266: 6241: 6209: 6186: 6166: 6135: 6104: 6061: 6037: 6017: 5987: 5954: 5934: 5913: 5886: 5865: 5833: 5780: 5744: 5717: 5696: 5663: 5642: 5622: 5601: 5568: 5548: 5464: 5441: 5417: 5393: 5378:. If a nonempty set 5365: 5344: 5323: 5218: 5197: 5174: 5086: 5046:in a similar manner: 5032: 5011: 4990: 4891: 4870: 4847: 4723: 4682: 4596: 4542: 4518: 4494: 4464: 4375: 4297: 4249: 4223: 4181: 4157: 4137: 4109: 4083: 4057: 4031: 4010: 3984: 3958: 3932: 3896: 3875: 3843: 3820: 3796: 3776: 3756: 3736: 3703: 3639: 3623: 3606:as the completion of 3601: 3063: 2903: 2881: 2767:Two Cauchy sequences 2531: 2509: 2428: 2399: 2368: 2340: 2214: 2082: 2056: 1951: 1911: 1825: 1793: 1759: 1733: 1673: 1596: 1428: 1391: 1297: 1182:model of real numbers 1102: 1069: 1032: 985: 928: 866: 805: 740: 695: 666: 664:{\displaystyle \leq } 642: 608: 582: 541: 515: 478: 437: 376: 303: 218: 177: 128: 77: 48:Axiomatic definitions 7410:IsarMathLib (2022). 7019: 6848:Faltin et al. (1975) 6810: 6790: 6770: 6738: 6718: 6692: 6627: 6597: 6569: 6525: 6434: 6398: 6337: 6282: 6253: 6222: 6198: 6175: 6144: 6124: 6082: 6046: 6026: 6003: 5997:extended real number 5963: 5943: 5922: 5895: 5874: 5842: 5789: 5753: 5726: 5705: 5672: 5651: 5631: 5610: 5577: 5557: 5485: 5450: 5426: 5402: 5382: 5353: 5332: 5227: 5206: 5185: 5095: 5053: 5020: 4999: 4900: 4879: 4858: 4732: 4700: 4610: 4551: 4527: 4507: 4473: 4389: 4316: 4258: 4238: 4194: 4166: 4146: 4122: 4092: 4066: 4040: 4020: 3993: 3967: 3941: 3905: 3885: 3854: 3832: 3805: 3785: 3765: 3745: 3712: 3691: 3610: 3588: 3181:consider the number 3045: 2890: 2868: 2850:equivalence relation 2518: 2496: 2415: 2386: 2355: 2327: 2201: 2069: 2043: 1938: 1898: 1812: 1780: 1746: 1720: 1657: 1580: 1403: 1306: 1203: 1148:Archimedean property 1086: 1056: 1019: 972: 915: 853: 792: 727: 682: 655: 629: 595: 569: 528: 502: 465: 424: 363: 290: 205: 164: 114: 64: 54:axiomatic definition 7421:Kemp, Todd (2016). 7015:For completions of 6843:Other constructions 6835:. This defines the 6612:{\displaystyle f,g} 6392:almost homomorphism 6239:{\displaystyle B/I} 5932:{\displaystyle x\,} 5884:{\displaystyle r\,} 5715:{\displaystyle y\,} 5661:{\displaystyle x\,} 5620:{\displaystyle A\,} 5363:{\displaystyle B\,} 5342:{\displaystyle A\,} 5216:{\displaystyle B\,} 5195:{\displaystyle A\,} 5030:{\displaystyle B\,} 5009:{\displaystyle A\,} 4889:{\displaystyle B\,} 4868:{\displaystyle A\,} 4501:relative complement 3701:{\displaystyle A\,} 3086:is rational. Since 2858:equivalence classes 2162: ≠  2154: ∈  2146: ≠  2138: ∈  2106: ∈  2098: ∈  1854:asymmetric relation 1166:nonfirstorderizable 137:must be satisfied. 60:, commonly denoted 7554:10.1007/bf03023955 7237:Faltin et al. 1975 7027: 6825: 6796: 6776: 6756: 6724: 6704: 6677: 6609: 6583: 6555: 6511: 6430:such that the set 6420: 6345: 6299: 6261: 6236: 6204: 6181: 6161: 6130: 6099: 6056: 6032: 6012: 5982: 5949: 5929: 5908: 5881: 5860: 5828: 5775: 5739: 5712: 5691: 5658: 5637: 5617: 5596: 5563: 5543: 5477:, we may take the 5459: 5436: 5412: 5388: 5360: 5339: 5318: 5213: 5192: 5169: 5081: 5070: 5027: 5006: 4985: 4886: 4865: 4842: 4718: 4677: 4591: 4537: 4513: 4489: 4459: 4370: 4292: 4244: 4218: 4176: 4152: 4132: 4104: 4078: 4062:such that for all 4052: 4026: 4005: 3979: 3953: 3927: 3891: 3870: 3838: 3815: 3791: 3771: 3751: 3731: 3698: 3650: 3618: 3596: 3518:and so neither is 3058: 2955:if and only if 2898: 2876: 2526: 2504: 2423: 2394: 2363: 2335: 2209: 2195:Axioms of addition 2077: 2051: 1984:such that for all 1946: 1906: 1820: 1788: 1754: 1728: 1668: 1591: 1423: 1386: 1292: 1097: 1064: 1045:. In other words, 1027: 980: 923: 861: 800: 735: 690: 671:. In other words, 661: 637: 603: 577: 536: 510: 473: 432: 371: 298: 213: 172: 123: 72: 7508:978-0-387-95297-0 7400:978-0-19-513087-4 7066:Math 25 Exercises 6799:{\displaystyle f} 6779:{\displaystyle f} 6727:{\displaystyle f} 6385:formally verified 6369:Eudoxus of Cnidus 6207:{\displaystyle I} 6184:{\displaystyle B} 6133:{\displaystyle B} 6076:hyperreal numbers 6053: 5952:{\displaystyle A} 5825: 5640:{\displaystyle A} 5566:{\displaystyle A} 5507: 5475:irrational number 5446:that is equal to 5433: 5409: 5391:{\displaystyle S} 5154: 5069: 4662: 4573: 4534: 4516:{\displaystyle B} 4480: 4444: 4274: 4247:{\displaystyle q} 4173: 4155:{\displaystyle A} 4129: 4029:{\displaystyle r} 3924: 3894:{\displaystyle r} 3867: 3841:{\displaystyle r} 3812: 3794:{\displaystyle r} 3774:{\displaystyle B} 3754:{\displaystyle A} 2961:is equivalent to 2653:Cauchy sequences 2435:Dedekind-complete 2263:, there exists a 1924:Dedekind-complete 1870:, there exists a 1768:, denoted by the 1706:primitive notions 1144:Dedekind-complete 1043:least upper bound 84:binary operations 7653: 7626: 7624: 7614: 7585: 7583: 7582: 7577: 7565: 7534: 7524: 7512: 7496: 7483: 7473: 7444: 7437:Nieuw Arch. Wisk 7429: 7427: 7415: 7404: 7381: 7379: 7350: 7331: 7304: 7302: 7287: 7285: 7274:A'Campo, Norbert 7259: 7246: 7240: 7234: 7228: 7222: 7216: 7210: 7204: 7198: 7192: 7186: 7180: 7179: 7145: 7139: 7138: 7129: 7120: 7114: 7108: 7102: 7096: 7081: 7075: 7069: 7063: 7057: 7051: 7045: 7036: 7034: 7033: 7028: 7026: 7013: 7007: 7006: 7004: 6998:. Archived from 6991: 6983: 6977: 6976: 6968: 6959: 6953: 6952: 6944: 6936: 6930: 6924: 6904: 6863:de Bruijn (1977) 6859:de Bruijn (1976) 6834: 6832: 6831: 6826: 6824: 6823: 6818: 6805: 6803: 6802: 6797: 6785: 6783: 6782: 6777: 6765: 6763: 6762: 6757: 6733: 6731: 6730: 6725: 6713: 6711: 6710: 6707:{\displaystyle } 6705: 6686: 6684: 6683: 6678: 6673: 6618: 6616: 6615: 6610: 6592: 6590: 6589: 6584: 6582: 6564: 6562: 6561: 6556: 6520: 6518: 6517: 6512: 6507: 6429: 6427: 6426: 6421: 6419: 6411: 6373:Shenitzer (1987) 6361:Stephen Schanuel 6354: 6352: 6351: 6346: 6344: 6308: 6306: 6305: 6300: 6298: 6293: 6292: 6270: 6268: 6267: 6262: 6260: 6245: 6243: 6242: 6237: 6232: 6213: 6211: 6210: 6205: 6190: 6188: 6187: 6182: 6170: 6168: 6167: 6162: 6160: 6155: 6154: 6139: 6137: 6136: 6131: 6117:. Consider the 6108: 6106: 6105: 6100: 6098: 6093: 6092: 6065: 6063: 6062: 6057: 6055: 6054: 6041: 6039: 6038: 6033: 6021: 6019: 6018: 6013: 5991: 5989: 5988: 5983: 5958: 5956: 5955: 5950: 5938: 5936: 5935: 5930: 5917: 5915: 5914: 5909: 5890: 5888: 5887: 5882: 5869: 5867: 5866: 5861: 5837: 5835: 5834: 5829: 5826: 5824: 5813: 5799: 5784: 5782: 5781: 5776: 5748: 5746: 5745: 5740: 5721: 5719: 5718: 5713: 5700: 5698: 5697: 5692: 5667: 5665: 5664: 5659: 5646: 5644: 5643: 5638: 5626: 5624: 5623: 5618: 5605: 5603: 5602: 5597: 5572: 5570: 5569: 5564: 5552: 5550: 5549: 5544: 5509: 5508: 5468: 5466: 5465: 5460: 5445: 5443: 5442: 5437: 5435: 5434: 5421: 5419: 5418: 5413: 5411: 5410: 5397: 5395: 5394: 5389: 5369: 5367: 5366: 5361: 5348: 5346: 5345: 5340: 5327: 5325: 5324: 5319: 5316: 5308: 5288: 5265: 5257: 5237: 5222: 5220: 5219: 5214: 5201: 5199: 5198: 5193: 5178: 5176: 5175: 5170: 5156: 5155: 5122: 5105: 5090: 5088: 5087: 5082: 5071: 5067: 5036: 5034: 5033: 5028: 5015: 5013: 5012: 5007: 4994: 4992: 4991: 4986: 4895: 4893: 4892: 4887: 4874: 4872: 4871: 4866: 4851: 4849: 4848: 4843: 4826: 4727: 4725: 4724: 4719: 4686: 4684: 4683: 4678: 4664: 4663: 4600: 4598: 4597: 4592: 4575: 4574: 4546: 4544: 4543: 4538: 4536: 4535: 4522: 4520: 4519: 4514: 4498: 4496: 4495: 4490: 4482: 4481: 4468: 4466: 4465: 4460: 4446: 4445: 4379: 4377: 4376: 4371: 4301: 4299: 4298: 4293: 4276: 4275: 4253: 4251: 4250: 4245: 4227: 4225: 4224: 4219: 4185: 4183: 4182: 4177: 4175: 4174: 4161: 4159: 4158: 4153: 4141: 4139: 4138: 4133: 4131: 4130: 4118:We form the set 4113: 4111: 4110: 4105: 4087: 4085: 4084: 4079: 4061: 4059: 4058: 4053: 4035: 4033: 4032: 4027: 4014: 4012: 4011: 4006: 3988: 3986: 3985: 3980: 3962: 3960: 3959: 3954: 3936: 3934: 3933: 3928: 3926: 3925: 3900: 3898: 3897: 3892: 3879: 3877: 3876: 3871: 3869: 3868: 3847: 3845: 3844: 3839: 3824: 3822: 3821: 3816: 3814: 3813: 3800: 3798: 3797: 3792: 3780: 3778: 3777: 3772: 3760: 3758: 3757: 3752: 3740: 3738: 3737: 3732: 3707: 3705: 3704: 3699: 3682:greatest element 3627: 3625: 3624: 3619: 3617: 3605: 3603: 3602: 3597: 3595: 3580: 3576: 3575:(1, 1, 1, 1,...) 3572: 3568: 3561: 3557: 3553: 3545:decimal notation 3539: 3535: 3529: 3523: 3517: 3513: 3502: 3496: 3481: 3468: 3462: 3448: 3438: 3434: 3412: 3406: 3398: 3392: 3386: 3375: 3369: 3363: 3352: 3346: 3330: 3311: 3290: 3270:. Otherwise set 3269: 3248: 3227: 3221: 3210: 3180: 3174: 3161: 3145: 3132: 3119: 3113: 3107: 3097: 3091: 3085: 3079: 3073: 3067: 3065: 3064: 3059: 3057: 3053: 3040: 3030: 3023: 3017: 3011: 3002: 2992: 2972: 2966: 2960: 2954: 2929: 2913: 2907: 2905: 2904: 2899: 2897: 2885: 2883: 2882: 2877: 2875: 2848:This defines an 2844: 2819: 2809: 2803: 2792: 2779: 2762: 2721: 2678: 2665: 2649: 2624: 2610: 2604: 2594: 2549: 2547: 2535: 2533: 2532: 2527: 2525: 2513: 2511: 2510: 2505: 2503: 2480:Cauchy sequences 2468:Karl Weierstrass 2460:Richard Dedekind 2432: 2430: 2429: 2424: 2422: 2406:linearly ordered 2403: 2401: 2400: 2395: 2393: 2372: 2370: 2369: 2364: 2362: 2351:. 1 βˆˆ  2344: 2342: 2341: 2336: 2334: 2313: <  2305: <  2293: <  2218: 2216: 2215: 2210: 2208: 2178: <  2170: <  2123:The real number 2114: <  2086: 2084: 2083: 2078: 2076: 2060: 2058: 2057: 2052: 2050: 2028: <  2020: <  1976: <  1955: 1953: 1952: 1947: 1945: 1915: 1913: 1912: 1907: 1905: 1886: <  1878: <  1866: <  1829: 1827: 1826: 1821: 1819: 1797: 1795: 1794: 1789: 1787: 1774:binary operation 1763: 1761: 1760: 1755: 1753: 1737: 1735: 1734: 1729: 1727: 1714:the real numbers 1677: 1675: 1674: 1669: 1664: 1652: 1646: 1640: 1614: 1600: 1598: 1597: 1592: 1587: 1575: 1569: 1563: 1524: 1483: 1467: 1441: 1432: 1430: 1429: 1424: 1416: 1395: 1393: 1392: 1387: 1379: 1378: 1366: 1365: 1353: 1352: 1340: 1339: 1327: 1326: 1301: 1299: 1298: 1293: 1288: 1287: 1286: 1273: 1272: 1271: 1258: 1257: 1256: 1243: 1242: 1241: 1228: 1227: 1226: 1213: 1106: 1104: 1103: 1098: 1093: 1073: 1071: 1070: 1065: 1063: 1036: 1034: 1033: 1028: 1026: 989: 987: 986: 981: 979: 932: 930: 929: 924: 922: 870: 868: 867: 862: 860: 809: 807: 806: 801: 799: 744: 742: 741: 736: 734: 699: 697: 696: 691: 689: 670: 668: 667: 662: 646: 644: 643: 638: 636: 612: 610: 609: 604: 602: 586: 584: 583: 578: 576: 545: 543: 542: 537: 535: 519: 517: 516: 511: 509: 482: 480: 479: 474: 472: 441: 439: 438: 433: 431: 380: 378: 377: 372: 370: 307: 305: 304: 299: 297: 222: 220: 219: 214: 212: 181: 179: 178: 173: 171: 132: 130: 129: 124: 105: 101: 81: 79: 78: 73: 71: 7661: 7660: 7656: 7655: 7654: 7652: 7651: 7650: 7631: 7630: 7629: 7580: 7578: 7575: 7522: 7509: 7425: 7401: 7268: 7263: 7262: 7247: 7243: 7235: 7231: 7223: 7219: 7211: 7207: 7199: 7195: 7187: 7183: 7168: 7146: 7142: 7127: 7121: 7117: 7109: 7105: 7097: 7084: 7076: 7072: 7064: 7060: 7052: 7048: 7022: 7020: 7017: 7016: 7014: 7010: 7002: 6989: 6985: 6984: 6980: 6966: 6960: 6956: 6942: 6938: 6937: 6933: 6925: 6921: 6916: 6902: 6895: 6845: 6819: 6814: 6813: 6811: 6808: 6807: 6791: 6788: 6787: 6771: 6768: 6767: 6739: 6736: 6735: 6719: 6716: 6715: 6693: 6690: 6689: 6669: 6628: 6625: 6624: 6598: 6595: 6594: 6578: 6570: 6567: 6566: 6526: 6523: 6522: 6503: 6435: 6432: 6431: 6415: 6407: 6399: 6396: 6395: 6371:. As noted by 6340: 6338: 6335: 6334: 6331: 6319:surreal numbers 6315: 6294: 6288: 6285: 6283: 6280: 6279: 6273:axiom of choice 6256: 6254: 6251: 6250: 6228: 6223: 6220: 6219: 6199: 6196: 6195: 6176: 6173: 6172: 6156: 6150: 6147: 6145: 6142: 6141: 6125: 6122: 6121: 6094: 6088: 6085: 6083: 6080: 6079: 6072: 6050: 6049: 6047: 6044: 6043: 6027: 6024: 6023: 6004: 6001: 6000: 5964: 5961: 5960: 5944: 5941: 5940: 5923: 5920: 5919: 5896: 5893: 5892: 5875: 5872: 5871: 5843: 5840: 5839: 5814: 5800: 5798: 5790: 5787: 5786: 5754: 5751: 5750: 5727: 5724: 5723: 5706: 5703: 5702: 5673: 5670: 5669: 5652: 5649: 5648: 5632: 5629: 5628: 5611: 5608: 5607: 5578: 5575: 5574: 5558: 5555: 5554: 5504: 5503: 5486: 5483: 5482: 5451: 5448: 5447: 5430: 5429: 5427: 5424: 5423: 5406: 5405: 5403: 5400: 5399: 5383: 5380: 5379: 5354: 5351: 5350: 5333: 5330: 5329: 5309: 5304: 5284: 5258: 5253: 5233: 5228: 5225: 5224: 5207: 5204: 5203: 5186: 5183: 5182: 5151: 5150: 5118: 5101: 5096: 5093: 5092: 5068: and  5065: 5054: 5051: 5050: 5021: 5018: 5017: 5000: 4997: 4996: 4901: 4898: 4897: 4880: 4877: 4876: 4859: 4856: 4855: 4822: 4733: 4730: 4729: 4701: 4698: 4697: 4659: 4658: 4611: 4608: 4607: 4570: 4569: 4552: 4549: 4548: 4531: 4530: 4528: 4525: 4524: 4508: 4505: 4504: 4477: 4476: 4474: 4471: 4470: 4441: 4440: 4390: 4387: 4386: 4317: 4314: 4313: 4271: 4270: 4259: 4256: 4255: 4239: 4236: 4235: 4195: 4192: 4191: 4186:, and define a 4170: 4169: 4167: 4164: 4163: 4147: 4144: 4143: 4126: 4125: 4123: 4120: 4119: 4093: 4090: 4089: 4067: 4064: 4063: 4041: 4038: 4037: 4021: 4018: 4017: 3994: 3991: 3990: 3968: 3965: 3964: 3942: 3939: 3938: 3921: 3920: 3906: 3903: 3902: 3886: 3883: 3882: 3864: 3863: 3855: 3852: 3851: 3833: 3830: 3829: 3809: 3808: 3806: 3803: 3802: 3786: 3783: 3782: 3766: 3763: 3762: 3746: 3743: 3742: 3713: 3710: 3709: 3692: 3689: 3688: 3634: 3613: 3611: 3608: 3607: 3591: 3589: 3586: 3585: 3578: 3574: 3570: 3563: 3562:. The equation 3559: 3555: 3548: 3537: 3531: 3525: 3519: 3515: 3512: 3504: 3498: 3495: 3483: 3479: 3470: 3464: 3450: 3440: 3436: 3432: 3423: 3414: 3408: 3402: 3394: 3388: 3385: 3377: 3371: 3365: 3362: 3354: 3348: 3344: 3332: 3328: 3316: 3310: 3301: 3292: 3289: 3280: 3271: 3268: 3259: 3250: 3247: 3238: 3229: 3223: 3220: 3212: 3208: 3199: 3190: 3182: 3176: 3169: 3163: 3156: 3150: 3143: 3134: 3130: 3121: 3115: 3109: 3099: 3093: 3087: 3081: 3075: 3069: 3049: 3048: 3046: 3043: 3042: 3036: 3028: 3019: 3013: 3007: 2994: 2991: 2982: 2974: 2968: 2962: 2956: 2952: 2943: 2934: 2915: 2909: 2893: 2891: 2888: 2887: 2871: 2869: 2866: 2865: 2839: 2830: 2821: 2811: 2805: 2798: 2790: 2781: 2777: 2768: 2760: 2751: 2742: 2733: 2724: 2719: 2710: 2701: 2692: 2683: 2676: 2667: 2663: 2654: 2644: 2635: 2626: 2612: 2606: 2599: 2592: 2583: 2574: 2565: 2539: 2537: 2521: 2519: 2516: 2515: 2499: 2497: 2494: 2493: 2476: 2464:Joseph Bertrand 2447: 2418: 2416: 2413: 2412: 2389: 2387: 2384: 2383: 2358: 2356: 2353: 2352: 2345:, <, +, 1): 2330: 2328: 2325: 2324: 2237:) = ( 2204: 2202: 2199: 2198: 2072: 2070: 2067: 2066: 2046: 2044: 2041: 2040: 1941: 1939: 1936: 1935: 1901: 1899: 1896: 1895: 1815: 1813: 1810: 1809: 1806:Axioms of order 1783: 1781: 1778: 1777: 1749: 1747: 1744: 1743: 1740:binary relation 1723: 1721: 1718: 1717: 1690: 1684: 1660: 1658: 1655: 1654: 1648: 1642: 1631: 1618: 1610: 1603: 1583: 1581: 1578: 1577: 1571: 1565: 1554: 1537: 1526: 1515: 1498: 1487: 1482: 1476: 1469: 1466: 1460: 1453: 1437: 1412: 1404: 1401: 1400: 1374: 1370: 1361: 1357: 1348: 1344: 1335: 1331: 1322: 1318: 1307: 1304: 1303: 1282: 1281: 1277: 1267: 1266: 1262: 1252: 1251: 1247: 1237: 1236: 1232: 1222: 1221: 1217: 1209: 1204: 1201: 1200: 1178: 1140: 1089: 1087: 1084: 1083: 1059: 1057: 1054: 1053: 1022: 1020: 1017: 1016: 1011:The order ≀ is 975: 973: 970: 969: 918: 916: 913: 912: 856: 854: 851: 850: 795: 793: 790: 789: 730: 728: 725: 724: 685: 683: 680: 679: 656: 653: 652: 649:totally ordered 632: 630: 627: 626: 598: 596: 593: 592: 572: 570: 567: 566: 531: 529: 526: 525: 505: 503: 500: 499: 468: 466: 463: 462: 427: 425: 422: 421: 366: 364: 361: 360: 293: 291: 288: 287: 208: 206: 203: 202: 167: 165: 162: 161: 158: 115: 112: 111: 103: 99: 88:binary relation 67: 65: 62: 61: 50: 12: 11: 5: 7659: 7649: 7648: 7643: 7628: 7627: 7605:(3): 737–762. 7587: 7586: 7567: 7566: 7536: 7535: 7514: 7513: 7507: 7485: 7484: 7464:(4): 813–824. 7446: 7445: 7431: 7430: 7417: 7416: 7406: 7405: 7399: 7383: 7382: 7370:(3): 278–304. 7352: 7351: 7337: 7336: 7322:(2): 100–108. 7306: 7305: 7289: 7288: 7269: 7267: 7264: 7261: 7260: 7241: 7229: 7217: 7205: 7193: 7181: 7166: 7140: 7115: 7103: 7082: 7070: 7058: 7046: 7025: 7008: 6978: 6954: 6940:"Real Numbers" 6931: 6918: 6917: 6915: 6912: 6911: 6910: 6905: 6894: 6891: 6880: 6879: 6870: 6865: 6844: 6841: 6822: 6817: 6795: 6786:is bounded or 6775: 6755: 6752: 6749: 6746: 6743: 6723: 6703: 6700: 6697: 6676: 6672: 6668: 6665: 6662: 6659: 6656: 6653: 6650: 6647: 6644: 6641: 6638: 6635: 6632: 6608: 6605: 6602: 6581: 6577: 6574: 6554: 6551: 6548: 6545: 6542: 6539: 6536: 6533: 6530: 6510: 6506: 6502: 6499: 6496: 6493: 6490: 6487: 6484: 6481: 6478: 6475: 6472: 6469: 6466: 6463: 6460: 6457: 6454: 6451: 6448: 6445: 6442: 6439: 6418: 6414: 6410: 6406: 6403: 6343: 6330: 6327: 6314: 6311: 6297: 6291: 6287: 6259: 6235: 6231: 6227: 6203: 6180: 6159: 6153: 6149: 6129: 6097: 6091: 6087: 6071: 6068: 6031: 6011: 6008: 5980: 5977: 5974: 5971: 5968: 5948: 5927: 5906: 5903: 5900: 5879: 5859: 5856: 5853: 5850: 5847: 5838:works. Then 5823: 5820: 5817: 5812: 5809: 5806: 5803: 5797: 5794: 5774: 5770: 5767: 5764: 5761: 5758: 5737: 5734: 5731: 5710: 5689: 5686: 5683: 5680: 5677: 5656: 5636: 5615: 5594: 5591: 5588: 5585: 5582: 5562: 5542: 5539: 5536: 5533: 5530: 5527: 5524: 5521: 5518: 5515: 5512: 5502: 5499: 5496: 5493: 5490: 5471: 5470: 5458: 5455: 5387: 5373: 5372: 5371: 5358: 5337: 5315: 5312: 5307: 5303: 5300: 5297: 5294: 5291: 5287: 5283: 5280: 5277: 5274: 5271: 5268: 5264: 5261: 5256: 5252: 5249: 5246: 5243: 5240: 5236: 5232: 5211: 5190: 5179: 5168: 5165: 5162: 5159: 5149: 5146: 5143: 5140: 5137: 5134: 5131: 5128: 5125: 5121: 5117: 5114: 5111: 5108: 5104: 5100: 5080: 5077: 5074: 5064: 5061: 5058: 5040: 5039: 5038: 5025: 5004: 4983: 4980: 4977: 4974: 4971: 4968: 4965: 4962: 4959: 4956: 4953: 4950: 4947: 4944: 4941: 4938: 4935: 4932: 4929: 4926: 4923: 4920: 4917: 4914: 4911: 4908: 4905: 4884: 4863: 4852: 4841: 4838: 4835: 4832: 4829: 4825: 4821: 4818: 4815: 4812: 4809: 4806: 4803: 4800: 4797: 4794: 4791: 4788: 4785: 4782: 4779: 4776: 4773: 4770: 4767: 4764: 4761: 4758: 4755: 4752: 4749: 4746: 4743: 4740: 4737: 4717: 4714: 4711: 4708: 4705: 4691:multiplication 4687: 4676: 4673: 4670: 4667: 4657: 4654: 4651: 4648: 4645: 4642: 4639: 4636: 4633: 4630: 4627: 4624: 4621: 4618: 4615: 4601: 4590: 4587: 4584: 4581: 4578: 4568: 4565: 4562: 4559: 4556: 4512: 4488: 4485: 4458: 4455: 4452: 4449: 4439: 4436: 4433: 4430: 4427: 4424: 4421: 4418: 4415: 4412: 4409: 4406: 4403: 4400: 4397: 4394: 4380: 4369: 4366: 4363: 4360: 4357: 4354: 4351: 4348: 4345: 4342: 4339: 4336: 4333: 4330: 4327: 4324: 4321: 4307: 4291: 4288: 4285: 4282: 4279: 4269: 4266: 4263: 4243: 4228: 4217: 4214: 4211: 4208: 4205: 4202: 4199: 4188:total ordering 4151: 4115: 4114: 4103: 4100: 4097: 4077: 4074: 4071: 4051: 4048: 4045: 4025: 4015: 4004: 4001: 3998: 3978: 3975: 3972: 3952: 3949: 3946: 3919: 3916: 3913: 3910: 3890: 3880: 3862: 3859: 3849: 3837: 3790: 3770: 3750: 3729: 3726: 3723: 3720: 3717: 3696: 3633: 3630: 3616: 3594: 3508: 3491: 3475: 3449:. Now suppose 3428: 3419: 3381: 3358: 3340: 3324: 3306: 3296: 3285: 3275: 3264: 3254: 3243: 3233: 3216: 3204: 3195: 3186: 3167: 3154: 3139: 3126: 3056: 3052: 2987: 2978: 2948: 2939: 2896: 2874: 2835: 2826: 2786: 2773: 2765: 2764: 2756: 2747: 2738: 2729: 2722: 2715: 2706: 2697: 2688: 2672: 2659: 2640: 2631: 2596: 2595: 2588: 2579: 2570: 2524: 2502: 2475: 2472: 2446: 2443: 2421: 2392: 2361: 2333: 2321:Axioms for one 2245:) +  2229: + ( 2207: 2192: 2191: 2184: 2183: 2120: 2119: 2075: 2049: 1944: 1904: 1818: 1786: 1770:infix operator 1752: 1726: 1694:axiomatization 1686:Main article: 1683: 1680: 1679: 1678: 1667: 1663: 1627: 1616:if and only if 1608: 1601: 1590: 1586: 1550: 1535: 1511: 1496: 1485: 1478: 1474: 1462: 1458: 1451: 1422: 1419: 1415: 1411: 1408: 1385: 1382: 1377: 1373: 1369: 1364: 1360: 1356: 1351: 1347: 1343: 1338: 1334: 1330: 1325: 1321: 1317: 1314: 1311: 1291: 1285: 1280: 1276: 1270: 1265: 1261: 1255: 1250: 1246: 1240: 1235: 1231: 1225: 1220: 1216: 1212: 1208: 1196:isomorphisms. 1177: 1174: 1146:, implies the 1139: 1136: 1135: 1134: 1133: 1132: 1096: 1092: 1062: 1025: 1009: 1008: 1007: 978: 958: 921: 894: 893: 892: 859: 839: 798: 774: 733: 713: 688: 660: 635: 624: 623: 622: 601: 575: 559: 534: 508: 492: 471: 455: 430: 414: 411:distributivity 369: 345: 296: 276: 211: 170: 157: 154: 122: 119: 96:multiplication 70: 49: 46: 9: 6: 4: 3: 2: 7658: 7647: 7644: 7642: 7639: 7638: 7636: 7623: 7618: 7613: 7608: 7604: 7600: 7599: 7594: 7589: 7588: 7574: 7569: 7568: 7563: 7559: 7555: 7551: 7547: 7543: 7538: 7537: 7532: 7528: 7521: 7516: 7515: 7510: 7504: 7500: 7495: 7494: 7487: 7486: 7481: 7477: 7472: 7467: 7463: 7459: 7458: 7453: 7448: 7447: 7442: 7438: 7433: 7432: 7424: 7419: 7418: 7413: 7412:"IsarMathLib" 7408: 7407: 7402: 7396: 7392: 7391: 7385: 7384: 7378: 7373: 7369: 7365: 7364: 7359: 7354: 7353: 7349:(9): 121–125. 7348: 7344: 7339: 7338: 7335: 7329: 7325: 7321: 7317: 7313: 7308: 7307: 7301: 7296: 7291: 7290: 7284: 7279: 7275: 7271: 7270: 7257: 7253: 7250: 7245: 7238: 7233: 7226: 7221: 7214: 7209: 7202: 7197: 7190: 7185: 7177: 7173: 7169: 7167:0-387-98464-X 7163: 7159: 7155: 7151: 7144: 7136: 7135: 7126: 7119: 7112: 7107: 7100: 7095: 7093: 7091: 7089: 7087: 7079: 7074: 7067: 7062: 7055: 7050: 7043: 7042:-adic numbers 7041: 7012: 7001: 6997: 6996: 6988: 6982: 6974: 6973: 6965: 6958: 6950: 6949: 6941: 6935: 6928: 6923: 6919: 6909: 6906: 6900: 6897: 6896: 6890: 6887: 6885: 6878: 6874: 6871: 6869: 6868:Rieger (1982) 6866: 6864: 6860: 6857: 6856: 6855: 6852: 6849: 6840: 6838: 6820: 6793: 6773: 6750: 6744: 6741: 6721: 6698: 6666: 6663: 6660: 6654: 6648: 6645: 6639: 6633: 6622: 6606: 6603: 6600: 6575: 6572: 6549: 6546: 6540: 6534: 6528: 6500: 6497: 6494: 6491: 6488: 6482: 6476: 6473: 6467: 6461: 6458: 6452: 6449: 6446: 6440: 6404: 6401: 6393: 6388: 6386: 6382: 6378: 6377:Arthan (2004) 6374: 6370: 6366: 6365:Eudoxus reals 6362: 6358: 6357:Arthan (2004) 6326: 6324: 6320: 6310: 6289: 6286: 6276: 6274: 6249: 6233: 6229: 6225: 6217: 6216:infinitesimal 6201: 6194: 6193:maximal ideal 6191:has a unique 6178: 6151: 6148: 6127: 6120: 6116: 6115:hyperintegers 6112: 6089: 6086: 6077: 6067: 6006: 5998: 5993: 5978: 5975: 5972: 5969: 5966: 5946: 5925: 5904: 5901: 5898: 5877: 5857: 5854: 5851: 5848: 5845: 5821: 5818: 5815: 5810: 5807: 5804: 5801: 5795: 5792: 5772: 5768: 5765: 5762: 5759: 5756: 5735: 5732: 5729: 5708: 5687: 5684: 5681: 5678: 5675: 5654: 5634: 5613: 5592: 5589: 5586: 5583: 5580: 5560: 5537: 5534: 5531: 5528: 5525: 5522: 5519: 5516: 5513: 5510: 5500: 5497: 5491: 5488: 5480: 5476: 5456: 5453: 5385: 5377: 5374: 5356: 5335: 5313: 5310: 5305: 5301: 5298: 5295: 5289: 5285: 5281: 5278: 5272: 5269: 5262: 5259: 5254: 5250: 5244: 5241: 5238: 5234: 5230: 5209: 5188: 5180: 5160: 5144: 5141: 5138: 5135: 5132: 5129: 5126: 5123: 5119: 5115: 5109: 5106: 5102: 5098: 5078: 5075: 5072: 5062: 5059: 5056: 5048: 5047: 5045: 5041: 5023: 5002: 4978: 4975: 4972: 4969: 4966: 4960: 4954: 4951: 4948: 4945: 4939: 4936: 4930: 4927: 4924: 4921: 4915: 4912: 4909: 4906: 4903: 4882: 4861: 4853: 4836: 4833: 4830: 4827: 4819: 4816: 4810: 4804: 4801: 4798: 4795: 4792: 4789: 4786: 4783: 4780: 4777: 4774: 4771: 4768: 4765: 4762: 4759: 4756: 4753: 4750: 4744: 4741: 4738: 4735: 4715: 4712: 4709: 4706: 4703: 4695: 4694: 4692: 4688: 4668: 4652: 4649: 4646: 4643: 4640: 4637: 4634: 4631: 4628: 4625: 4619: 4616: 4613: 4605: 4602: 4585: 4582: 4579: 4576: 4566: 4563: 4560: 4557: 4510: 4502: 4486: 4450: 4434: 4431: 4428: 4425: 4422: 4419: 4416: 4413: 4410: 4407: 4401: 4398: 4395: 4392: 4384: 4381: 4364: 4361: 4358: 4355: 4352: 4349: 4346: 4343: 4340: 4337: 4334: 4328: 4325: 4322: 4319: 4311: 4308: 4305: 4286: 4283: 4280: 4277: 4267: 4264: 4241: 4233: 4229: 4215: 4212: 4209: 4203: 4200: 4197: 4189: 4149: 4117: 4116: 4101: 4098: 4095: 4075: 4072: 4069: 4049: 4046: 4043: 4023: 4016: 4002: 3999: 3996: 3976: 3973: 3970: 3950: 3947: 3944: 3917: 3914: 3911: 3908: 3888: 3881: 3860: 3857: 3850: 3835: 3828: 3827: 3826: 3788: 3768: 3748: 3724: 3721: 3718: 3694: 3685: 3683: 3679: 3675: 3671: 3668:), such that 3667: 3663: 3659: 3655: 3647: 3643: 3638: 3629: 3582: 3566: 3551: 3546: 3541: 3540:is complete. 3534: 3528: 3522: 3511: 3507: 3501: 3494: 3490: 3486: 3478: 3474: 3467: 3461: 3457: 3453: 3447: 3443: 3431: 3427: 3422: 3418: 3411: 3405: 3399: 3397: 3391: 3384: 3380: 3374: 3368: 3361: 3357: 3351: 3343: 3339: 3335: 3327: 3323: 3319: 3313: 3309: 3305: 3299: 3295: 3288: 3284: 3278: 3274: 3267: 3263: 3257: 3253: 3246: 3242: 3236: 3232: 3226: 3219: 3215: 3207: 3203: 3198: 3194: 3189: 3185: 3179: 3173: 3166: 3160: 3153: 3147: 3142: 3138: 3129: 3125: 3118: 3112: 3106: 3102: 3096: 3090: 3084: 3078: 3072: 3054: 3039: 3034: 3025: 3022: 3016: 3010: 3004: 3001: 2997: 2990: 2986: 2981: 2977: 2971: 2965: 2959: 2951: 2947: 2942: 2938: 2931: 2927: 2923: 2919: 2912: 2863: 2859: 2855: 2851: 2846: 2843: 2838: 2834: 2829: 2825: 2818: 2814: 2808: 2801: 2796: 2789: 2785: 2776: 2772: 2759: 2755: 2750: 2746: 2741: 2737: 2732: 2728: 2723: 2718: 2714: 2709: 2705: 2700: 2696: 2691: 2687: 2682: 2681: 2680: 2675: 2671: 2662: 2658: 2651: 2648: 2643: 2639: 2634: 2630: 2623: 2619: 2615: 2609: 2602: 2591: 2587: 2582: 2578: 2573: 2569: 2564: 2563: 2562: 2560: 2556: 2551: 2546: 2542: 2491: 2489: 2485: 2481: 2471: 2469: 2465: 2461: 2457: 2456:Charles MΓ©ray 2453: 2442: 2440: 2436: 2410: 2409:abelian group 2407: 2380: 2378: 2374: 2350: 2346: 2323:(primitives: 2322: 2318: 2316: 2312: 2308: 2304: 2300: 2297: +  2296: 2292: 2289: +  2288: 2284: 2280: 2278: 2275: =  2274: 2271: +  2270: 2266: 2262: 2258: 2254: 2250: 2248: 2244: 2241: +  2240: 2236: 2233: +  2232: 2228: 2224: 2220: 2197:(primitives: 2196: 2189: 2188: 2187: 2181: 2177: 2173: 2169: 2165: 2161: 2157: 2153: 2149: 2145: 2141: 2137: 2133: 2129: 2126: 2122: 2121: 2117: 2113: 2109: 2105: 2101: 2097: 2093: 2090: 2089: 2088: 2065: βŠ†  2064: 2039: βŠ†  2038: 2033: 2031: 2027: 2023: 2019: 2015: 2012: β‰   2011: 2007: 2004: β‰   2003: 1999: 1996: βˆˆ  1995: 1991: 1988: βˆˆ  1987: 1983: 1979: 1975: 1971: 1968: βˆˆ  1967: 1963: 1960: βˆˆ  1959: 1956:, if for all 1934: βŠ†  1933: 1929: 1925: 1921: 1917: 1893: 1889: 1885: 1881: 1877: 1873: 1869: 1865: 1861: 1857: 1855: 1851: 1847: 1843: 1839: 1835: 1831: 1808:(primitives: 1807: 1803: 1801: 1775: 1771: 1767: 1741: 1715: 1711: 1707: 1703: 1699: 1698:Alfred Tarski 1695: 1689: 1665: 1651: 1645: 1638: 1634: 1630: 1625: 1621: 1617: 1613: 1606: 1602: 1588: 1574: 1568: 1561: 1557: 1553: 1548: 1544: 1540: 1533: 1529: 1522: 1518: 1514: 1509: 1505: 1501: 1494: 1490: 1486: 1481: 1472: 1465: 1456: 1452: 1449: 1445: 1440: 1436: 1435: 1434: 1420: 1409: 1406: 1399: 1383: 1375: 1371: 1367: 1362: 1358: 1354: 1349: 1345: 1341: 1336: 1332: 1328: 1323: 1319: 1315: 1312: 1278: 1274: 1263: 1259: 1248: 1244: 1233: 1229: 1218: 1214: 1197: 1195: 1191: 1187: 1183: 1173: 1171: 1167: 1162: 1160: 1156: 1155:ordered field 1151: 1149: 1145: 1130: 1126: 1122: 1118: 1114: 1110: 1094: 1081: 1077: 1051: 1047: 1046: 1044: 1040: 1039:bounded above 1014: 1010: 1005: 1001: 997: 993: 967: 963: 959: 956: 952: 948: 944: 940: 936: 910: 906: 902: 898: 897: 895: 890: 886: 882: 878: 874: 848: 844: 840: 837: 833: 829: 825: 821: 817: 813: 787: 783: 779: 775: 772: 768: 764: 760: 756: 752: 748: 722: 718: 714: 711: 707: 703: 677: 673: 672: 658: 650: 625: 620: 616: 590: 564: 560: 557: 553: 549: 523: 497: 493: 490: 486: 460: 456: 453: 449: 445: 419: 415: 412: 408: 404: 400: 396: 392: 388: 384: 358: 354: 350: 346: 343: 342:commutativity 339: 335: 331: 327: 323: 319: 315: 311: 285: 281: 277: 274: 273:associativity 270: 266: 262: 258: 254: 250: 246: 242: 238: 234: 230: 226: 200: 196: 192: 188: 187: 185: 160: 159: 153: 151: 147: 143: 138: 136: 120: 117: 109: 97: 93: 89: 85: 59: 55: 45: 42: 41:ordered field 38: 33: 31: 27: 23: 19: 7641:Real numbers 7602: 7596: 7579:. Retrieved 7548:(3): 44–52. 7545: 7541: 7530: 7526: 7492: 7461: 7455: 7440: 7436: 7389: 7367: 7361: 7346: 7342: 7319: 7315: 7300:math/0405454 7283:math/0301015 7266:Bibliography 7244: 7232: 7220: 7208: 7201:A'Campo 2003 7196: 7184: 7149: 7143: 7131: 7118: 7106: 7073: 7061: 7049: 7039: 7011: 7000:the original 6993: 6981: 6970: 6957: 6946: 6934: 6922: 6888: 6884:Weiss (2015) 6881: 6853: 6846: 6837:linear order 6734:we say that 6621:almost equal 6620: 6391: 6389: 6364: 6332: 6316: 6277: 6073: 6042:with all of 5994: 5472: 4499:denotes the 3848:is not empty 3686: 3680:contains no 3677: 3673: 3669: 3665: 3661: 3654:Dedekind cut 3651: 3646:real numbers 3583: 3549: 3542: 3532: 3526: 3520: 3509: 3505: 3499: 3492: 3488: 3484: 3476: 3472: 3465: 3459: 3455: 3451: 3445: 3441: 3429: 3425: 3420: 3416: 3409: 3403: 3400: 3395: 3389: 3382: 3378: 3372: 3366: 3359: 3355: 3349: 3341: 3337: 3333: 3325: 3321: 3317: 3314: 3307: 3303: 3297: 3293: 3286: 3282: 3276: 3272: 3265: 3261: 3255: 3251: 3244: 3240: 3234: 3230: 3224: 3217: 3213: 3205: 3201: 3196: 3192: 3187: 3183: 3177: 3171: 3164: 3158: 3151: 3148: 3146:as follows: 3140: 3136: 3127: 3123: 3116: 3110: 3104: 3100: 3094: 3088: 3082: 3076: 3070: 3037: 3026: 3020: 3014: 3008: 3005: 2999: 2995: 2993:for all 2988: 2984: 2979: 2975: 2969: 2963: 2957: 2949: 2945: 2940: 2936: 2932: 2925: 2921: 2917: 2910: 2853: 2847: 2841: 2836: 2832: 2827: 2823: 2816: 2812: 2806: 2799: 2794: 2787: 2783: 2774: 2770: 2766: 2757: 2753: 2748: 2744: 2739: 2735: 2730: 2726: 2716: 2712: 2707: 2703: 2698: 2694: 2689: 2685: 2673: 2669: 2660: 2656: 2652: 2646: 2641: 2637: 2632: 2628: 2621: 2617: 2613: 2607: 2600: 2597: 2589: 2585: 2580: 2576: 2571: 2567: 2554: 2552: 2544: 2540: 2492: 2484:metric space 2477: 2452:Georg Cantor 2448: 2381: 2376: 2375: 2348: 2347: 2320: 2319: 2314: 2310: 2306: 2302: 2298: 2294: 2290: 2286: 2282: 2281: 2276: 2272: 2268: 2264: 2260: 2256: 2252: 2251: 2246: 2242: 2238: 2234: 2230: 2226: 2222: 2221: 2219:, <, +): 2194: 2193: 2185: 2179: 2175: 2171: 2167: 2163: 2159: 2155: 2151: 2147: 2143: 2139: 2135: 2131: 2127: 2124: 2115: 2111: 2107: 2103: 2099: 2095: 2092:X precedes Y 2091: 2062: 2036: 2034: 2029: 2025: 2021: 2017: 2013: 2009: 2005: 2001: 1997: 1993: 1989: 1985: 1981: 1977: 1973: 1969: 1965: 1961: 1957: 1931: 1927: 1922:. "<" is 1919: 1918: 1887: 1883: 1879: 1875: 1871: 1867: 1863: 1859: 1858: 1849: 1845: 1841: 1837: 1833: 1832: 1805: 1804: 1799: 1765: 1713: 1691: 1649: 1643: 1636: 1632: 1628: 1623: 1619: 1611: 1604: 1572: 1566: 1559: 1555: 1551: 1546: 1542: 1538: 1531: 1527: 1520: 1516: 1512: 1507: 1503: 1499: 1492: 1488: 1479: 1470: 1463: 1454: 1438: 1198: 1181: 1179: 1163: 1158: 1152: 1141: 1128: 1124: 1120: 1116: 1112: 1108: 1075: 1049: 1012: 1003: 999: 995: 991: 965: 961: 954: 950: 946: 942: 938: 934: 908: 904: 900: 884: 880: 876: 872: 846: 842: 836:transitivity 831: 827: 823: 819: 815: 811: 785: 781: 777: 771:antisymmetry 766: 762: 758: 754: 750: 746: 720: 716: 705: 701: 675: 618: 614: 613:, such that 588: 562: 551: 547: 546:, such that 521: 495: 488: 484: 458: 447: 443: 417: 406: 402: 398: 394: 390: 386: 382: 356: 352: 348: 337: 333: 329: 325: 321: 317: 313: 309: 283: 279: 268: 264: 260: 256: 252: 248: 244: 240: 236: 232: 228: 224: 198: 194: 190: 139: 107: 95: 91: 51: 34: 22:real numbers 15: 7443:(5): 19–31. 7225:IsarMathLib 7213:Street 2003 7189:Arthan 2004 7068:ucdavis.edu 6623:if the set 6381:proportions 6323:Archimedean 6111:ultrafilter 5785:The choice 5328:to convert 4995:to convert 4383:Subtraction 3554:means that 3552:= 3.1415... 3175:. For each 3031:, i.e. the 2793:are called 2125:z separates 1844:, then not 1641:, for all 1396:there is a 1080:upper bound 998:, then 0 ≀ 710:reflexivity 37:isomorphism 18:mathematics 7635:Categories 7612:1506.03467 7581:2010-10-23 7533:: 205–217. 7256:Rieger1982 7111:Hersh 1997 7080:furman.edu 6927:Weiss 2015 6914:References 6246:gives the 6074:As in the 5181:if either 5042:We define 4854:if either 3937:such that 3642:irrational 3543:The usual 3098:such that 2973:such that 2820:, one has 2795:equivalent 2734:) × ( 2625:, one has 2488:completion 2267:such that 2255:. For all 2150:and every 2102:and every 1874:such that 1716:, denoted 1564:, for all 1448:surjective 561:For every 550:+ (− 494:For every 110:, denoted 108:inequality 7562:122199850 7480:122161507 7099:Pugh 2002 7054:Kemp 2016 6745:≤ 6667:∈ 6646:− 6576:∈ 6573:α 6553:⌋ 6547:α 6544:⌊ 6501:∈ 6474:− 6459:− 6413:→ 6394:be a map 6290:∗ 6152:∗ 6090:∗ 6030:∞ 6010:∞ 6007:− 5976:× 5855:≤ 5849:× 5760:× 5679:× 5584:× 5529:× 5523:∨ 5501:∈ 5454:⋃ 5311:− 5299:− 5279:− 5273:− 5260:− 5245:− 5158:∖ 5145:∈ 5139:∧ 5133:∈ 5060:≥ 4976:− 4973:× 4967:− 4952:× 4946:− 4940:− 4928:− 4925:× 4916:− 4907:× 4820:∈ 4811:∪ 4802:∈ 4796:∧ 4790:≥ 4784:∧ 4778:∈ 4772:∧ 4766:≥ 4754:× 4739:× 4713:≥ 4689:Defining 4666:∖ 4653:∈ 4647:∧ 4629:− 4614:− 4583:∉ 4577:∧ 4567:∈ 4484:∖ 4448:∖ 4435:∈ 4429:∧ 4423:∈ 4411:− 4396:− 4362:∈ 4356:∧ 4350:∈ 4268:∈ 4213:⊆ 4207:⇔ 4201:≤ 4099:≤ 4073:∈ 4047:∈ 4000:∈ 3974:∈ 3918:∈ 3861:≠ 3658:partition 3497:for some 3439:, and so 3108:for some 2439:divisible 1830:, <): 1444:injective 1418:→ 1410:: 1398:bijection 1372:≤ 1359:× 1279:≤ 1264:× 1176:On models 1074:, and if 990:, if 0 ≀ 659:≤ 142:structure 118:≤ 7332:also at 7078:1.2–Cuts 6893:See also 6171:. Then 5376:Supremum 5044:division 4604:Negation 4310:Addition 3741:, since 3660:of it, ( 3565:0.999... 3524:. Hence 3469:. Since 3393:for any 3370:for all 3055:′ 2433:is also 1800:addition 1772:<, a 1442:is both 1037:that is 1013:complete 994:and 0 ≀ 960:For all 899:For all 889:totality 841:For all 776:For all 715:For all 674:For all 556:inverses 452:identity 416:For all 347:For all 278:For all 189:For all 92:addition 86:and one 7176:1643950 6390:Let an 5016:and/or 2856:of all 2840:| < 2752:× 2645:| < 2557:be the 2377:Axiom 8 2349:Axiom 7 2301:, then 2283:Axiom 6 2253:Axiom 5 2223:Axiom 4 2016:, then 1930:,  1920:Axiom 3 1860:Axiom 2 1834:Axiom 1 1798:called 1764:called 1712:called 1078:has an 941:, then 826:, then 761:, then 565:β‰  0 in 146:theorem 7560:  7505:  7478:  7397:  7252:693180 7174:  7164:  6214:, the 4469:where 3503:. But 3228:, set 2944:) β‰₯ ( 2928:, ...) 2802:> 0 2603:> 0 2548:| 2538:| 1702:axioms 1041:has a 784:, and 487:Γ— 1 = 446:+ 0 = 355:, and 197:, and 156:Axioms 135:axioms 7607:arXiv 7576:(PDF) 7558:S2CID 7523:(PDF) 7501:–15. 7476:S2CID 7426:(PDF) 7295:arXiv 7278:arXiv 7128:(PDF) 7003:(PDF) 6990:(PDF) 6967:(PDF) 6943:(PDF) 6248:field 5959:with 5722:with 5668:with 5091:then 4728:then 4304:dense 4232:embed 3989:then 3963:, if 3487:< 3454:< 3401:Thus 3353:that 3211:. If 3103:< 2998:> 2815:> 2743:) = ( 2702:) = ( 2693:) + ( 2620:> 2593:,...) 2482:in a 2404:is a 2285:. If 2158:with 2142:with 2000:, if 1892:dense 1862:. If 1848:< 1840:< 1836:. If 1776:over 1766:order 1742:over 1477:) = 1 1461:) = 0 1194:up to 1190:below 1184:is a 1107:then 933:, if 810:, if 745:, if 401:) + ( 393:) = ( 259:) = ( 235:) = ( 184:field 182:is a 150:up to 144:is a 7503:ISBN 7395:ISBN 7162:ISBN 6619:are 6375:and 6119:ring 5970:< 5902:< 5766:< 5749:and 5733:< 5685:< 5535:< 5517:< 5076:> 4834:< 4641:< 4284:< 3948:< 3573:and 3536:and 3376:and 3331:and 3291:and 3249:and 3162:and 3149:Set 3133:and 3068:and 2780:and 2666:and 2553:Let 2466:and 2437:and 2174:and 2130:and 2061:and 2024:and 2008:and 1992:and 1964:and 1882:and 1738:, a 1708:: a 1647:and 1570:and 1541:) = 1525:and 1502:) = 1468:and 1446:and 1302:and 964:and 907:and 845:and 818:and 753:and 719:and 651:for 409:). ( 324:and 282:and 267:) Γ— 247:and 243:) + 102:and 94:and 7617:doi 7550:doi 7466:doi 7372:doi 7324:doi 7154:doi 6766:if 5939:in 5202:or 5049:if 4875:or 4696:if 4523:in 4503:of 4230:We 4162:of 3567:= 1 3435:is 3336:= ( 3320:= ( 3209:)/2 3191:= ( 3114:in 2983:β‰₯ 2559:set 2309:or 1894:in 1710:set 1653:in 1626:) ≀ 1576:in 1549:) Γ— 1510:) + 1119:of 1082:in 1048:If 968:in 911:in 887:. ( 879:or 849:in 834:. ( 788:in 769:. ( 723:in 708:. ( 678:in 647:is 591:in 524:in 498:in 461:in 420:in 385:Γ— ( 359:in 340:. ( 286:in 271:. ( 251:Γ— ( 227:+ ( 201:in 58:set 52:An 39:of 16:In 7637:: 7615:. 7603:45 7601:. 7595:. 7556:. 7544:. 7531:33 7529:. 7525:. 7499:11 7474:. 7462:18 7460:. 7454:. 7439:. 7368:16 7366:. 7360:. 7347:86 7345:. 7320:79 7318:. 7314:. 7249:MR 7172:MR 7170:. 7160:. 7130:. 7085:^ 7044:). 6992:. 6969:. 6945:. 6886:. 6875:, 6861:, 6275:. 6066:. 5992:. 5110::= 4745::= 4620::= 4547:, 4402::= 4385:. 4329::= 4312:. 4088:, 3664:, 3652:A 3644:, 3581:. 3458:= 3444:= 3424:βˆ’ 3312:. 3302:= 3300:+1 3281:= 3279:+1 3260:= 3258:+1 3239:= 3237:+1 3200:+ 3170:= 3157:= 3003:. 2930:. 2924:, 2920:, 2864:. 2845:. 2831:βˆ’ 2711:+ 2636:βˆ’ 2616:, 2584:, 2575:, 2543:βˆ’ 2490:. 2458:, 2441:. 2373:. 2317:. 2279:. 2259:, 2249:. 2225:. 2166:, 2110:, 2032:. 1972:, 1916:. 1856:. 1473:(1 1457:(0 1180:A 1172:. 1150:. 1127:≀ 1123:, 1002:Γ— 953:+ 949:≀ 945:+ 937:≀ 903:, 883:≀ 875:≀ 871:, 830:≀ 822:≀ 814:≀ 780:, 765:= 757:≀ 749:≀ 704:≀ 700:, 617:Γ— 483:, 442:, 405:Γ— 397:Γ— 389:+ 381:, 351:, 336:Γ— 332:= 328:Γ— 320:+ 316:= 312:+ 308:, 263:Γ— 255:Γ— 239:+ 231:+ 223:, 193:, 7625:. 7619:: 7609:: 7584:. 7564:. 7552:: 7546:9 7511:. 7482:. 7468:: 7441:4 7428:. 7414:. 7403:. 7380:. 7374:: 7330:. 7326:: 7303:. 7297:: 7286:. 7280:: 7258:. 7239:. 7227:. 7215:. 7203:. 7191:. 7178:. 7156:: 7137:. 7113:. 7101:. 7056:. 7040:p 7024:Q 6975:. 6951:. 6929:. 6821:+ 6816:Z 6794:f 6774:f 6754:] 6751:f 6748:[ 6742:0 6722:f 6702:] 6699:f 6696:[ 6675:} 6671:Z 6664:n 6661:: 6658:) 6655:n 6652:( 6649:g 6643:) 6640:n 6637:( 6634:f 6631:{ 6607:g 6604:, 6601:f 6580:R 6550:n 6541:= 6538:) 6535:n 6532:( 6529:f 6509:} 6505:Z 6498:m 6495:, 6492:n 6489:: 6486:) 6483:n 6480:( 6477:f 6471:) 6468:m 6465:( 6462:f 6456:) 6453:m 6450:+ 6447:n 6444:( 6441:f 6438:{ 6417:Z 6409:Z 6405:: 6402:f 6342:Z 6296:Q 6258:R 6234:I 6230:/ 6226:B 6202:I 6179:B 6158:Q 6128:B 6096:Q 6052:Q 5979:x 5973:x 5967:r 5947:A 5926:x 5905:2 5899:r 5878:r 5858:2 5852:A 5846:A 5822:2 5819:+ 5816:x 5811:2 5808:+ 5805:x 5802:2 5796:= 5793:y 5773:. 5769:2 5763:y 5757:y 5736:y 5730:x 5709:y 5688:2 5682:x 5676:x 5655:x 5635:A 5614:A 5593:2 5590:= 5587:A 5581:A 5561:A 5541:} 5538:2 5532:x 5526:x 5520:0 5514:x 5511:: 5506:Q 5498:x 5495:{ 5492:= 5489:A 5469:. 5457:S 5432:R 5408:R 5386:S 5357:B 5336:A 5314:B 5306:/ 5302:A 5296:= 5293:) 5290:B 5286:/ 5282:A 5276:( 5270:= 5267:) 5263:B 5255:/ 5251:A 5248:( 5242:= 5239:B 5235:/ 5231:A 5210:B 5189:A 5167:} 5164:) 5161:B 5153:Q 5148:( 5142:b 5136:A 5130:a 5127:: 5124:b 5120:/ 5116:a 5113:{ 5107:B 5103:/ 5099:A 5079:0 5073:B 5063:0 5057:A 5024:B 5003:A 4982:) 4979:B 4970:A 4964:( 4961:= 4958:) 4955:B 4949:A 4943:( 4937:= 4934:) 4931:B 4922:A 4919:( 4913:= 4910:B 4904:A 4883:B 4862:A 4840:} 4837:0 4831:x 4828:: 4824:Q 4817:x 4814:{ 4808:} 4805:B 4799:b 4793:0 4787:b 4781:A 4775:a 4769:0 4763:a 4760:: 4757:b 4751:a 4748:{ 4742:B 4736:A 4716:0 4710:B 4707:, 4704:A 4675:} 4672:) 4669:B 4661:Q 4656:( 4650:b 4644:0 4638:a 4635:: 4632:b 4626:a 4623:{ 4617:B 4589:} 4586:B 4580:x 4572:Q 4564:x 4561:: 4558:x 4555:{ 4533:Q 4511:B 4487:B 4479:Q 4457:} 4454:) 4451:B 4443:Q 4438:( 4432:b 4426:A 4420:a 4417:: 4414:b 4408:a 4405:{ 4399:B 4393:A 4368:} 4365:B 4359:b 4353:A 4347:a 4344:: 4341:b 4338:+ 4335:a 4332:{ 4326:B 4323:+ 4320:A 4290:} 4287:q 4281:x 4278:: 4273:Q 4265:x 4262:{ 4242:q 4216:y 4210:x 4204:y 4198:x 4172:Q 4150:A 4128:R 4102:x 4096:y 4076:r 4070:y 4050:r 4044:x 4024:r 4003:r 3997:x 3977:r 3971:y 3951:y 3945:x 3923:Q 3915:y 3912:, 3909:x 3889:r 3866:Q 3858:r 3836:r 3811:Q 3789:r 3769:B 3749:A 3728:) 3725:B 3722:, 3719:A 3716:( 3695:A 3678:A 3674:B 3670:A 3666:B 3662:A 3648:. 3615:Q 3593:R 3579:0 3556:Ο€ 3550:Ο€ 3538:≀ 3533:S 3527:u 3521:b 3516:S 3510:n 3506:l 3500:n 3493:n 3489:l 3485:b 3480:) 3477:n 3473:l 3471:( 3466:S 3460:l 3456:u 3452:b 3446:u 3442:l 3437:0 3433:) 3430:n 3426:l 3421:n 3417:u 3415:( 3410:S 3404:u 3396:n 3390:S 3383:n 3379:l 3373:n 3367:S 3360:n 3356:u 3350:n 3345:) 3342:n 3338:u 3334:u 3329:) 3326:n 3322:l 3318:l 3308:n 3304:u 3298:n 3294:u 3287:n 3283:m 3277:n 3273:l 3266:n 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237:x 233:z 229:y 225:x 210:R 199:z 195:y 191:x 169:R 121:. 104:Γ— 100:+ 69:R

Index

mathematics
real numbers
complete ordered field
mathematical structure
isomorphism
ordered field
axiomatic definition
set
binary operations
binary relation
axioms
structure
theorem
up to
field
associativity
commutativity
distributivity
identity
inverses
totally ordered
reflexivity
antisymmetry
transitivity
totality
bounded above
least upper bound
upper bound
Dedekind-complete
Archimedean property

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