Cantor diagonalization

Cantor never assumed he had a surjective function f:N→(0,1). What diagonlaization proves - directly, and not by contradiction - is that any such function cannot be surjective. The contradiction he talked about, was that a listing can't be complete, and non-surjective, at the same time.

The proof again uses the Cantor diagonalization, and is structurally identical to the second argument above concerning languages of arithmetic. Let us suppose that some sentences of L express existential thoughts, of the form ∃xF(x), where F is a purely syntactic property of some L-sentences. If S is such an existential sentence, then it is ...Lembrem-se de se inscrever no canal e também de curtir o vídeo. Quanto mais curtida e mais inscritos, mais o sistema de busca do Youtube divulga o canal!Faça...Cool Math Episode 1: https://www.youtube.com/watch?v=WQWkG9cQ8NQ In the first episode we saw that the integers and rationals (numbers like 3/5) have the same...Apr 29, 2021 · Cantor Diagonalization. In summary, Cantor's diagonalization argument allows us to create a new number not on a given list by changing the first digit of the first number, the second digit of the second number, the third digit of the third number, etc.f. Apr 28, 2021. #1. $\begingroup$ I don't know to what Cantor diagonalization you're referring here: the only proof I know that the Cantor set is uncountable uses writing elements in base 3 and then an onto function. Cantor Diagonalization is used to show that the set of all real numbers in $\,[0,1]\,$ is uncountable. $\endgroup$ –The premise of the diagonal argument is that we can always find a digit b in the x th element of any given list of Q, which is different from the x th digit of that element q, and use it to construct a. However, when there exists a repeating sequence U, we need to ensure that b follows the pattern of U after the s th digit.

Cantor himself proved (before creating the diagonal proof) that the reals are uncountable by another method (based upon the fact that, in $\mathbb R$, every bounded monotonic sequence converges). There are other proofs that the reals are uncountable.Figure 1: Cantor's diagonal argument. In this gure we're identifying subsets of Nwith in nite binary sequences by letting the where the nth bit of the in nite binary sequence be 1 if nis an element of the set. This exact same argument generalizes to the following fact: Exercise 1.7. Show that for every set X, there is no surjection f: X!P(X).Cantor's Diagonal Argument (1891) Jørgen Veisdal. Jan 25, 2022. 7. "Diagonalization seems to show that there is an inexhaustibility phenomenon for definability similar to that for provability" — Franzén (2004) Colourized photograph of Georg Cantor and the first page of his 1891 paper introducing the diagonal argument.Disproving Cantor's diagonal argument. I am familiar with Cantor's diagonal argument and how it can be used to prove the uncountability of the set of real numbers. However I have an extremely simple objection to make. Given the following: Theorem: Every number with a finite number of digits has two representations in the set of rational numbers.In a recent analyst note, Pablo Zuanic from Cantor Fitzgerald offered an update on the performance of Canada’s cannabis Licensed Producers i... In a recent analyst note, Pablo Zuanic from Cantor Fitzgerald offered an update on the per...In set theory, Cantor’s diagonal argument, also called the diagonalisation argument, the diagonal slash argument, the anti-diagonal argument, the diagonal method, and Cantor’s diagonalization proof, was published in 1891 by Georg Cantor as a mathematical proof that there are infinite sets which cannot be put into one-to-one correspondence ...Return to Cantor's diagonal proof, and add to Cantor's 'diagonal rule' (R) the following rule (in a usual computer notation):. (R3) integer С; С := 1; for ...

Therefore Cantor's Diagonalization function result is not a new combination. Because the aleph0 long Cantor's Diagonalization function result cannot cover the 2^aleph0 list, it means that 2^aleph0 > aleph0, but we can define a map between any unique combination and some natural number, therefore 2^aleph0 = aleph0.A cantor or chanter is a person who leads people in singing or sometimes in prayer. In formal Jewish worship, a cantor is a person who sings solo verses or passages to which the choir or congregation responds. Overview. In Judaism, a cantor sings and leads congregants in prayer in Jewish religious services; sometimes called a hazzan.Cantor se aventuró a entrar en terrenos que otros temían pisar. Creía que el arte de preguntar era más valioso que resolver problemas y aunque fue rechazado en su época, sus ideas le han ...Cantor. The proof is often referred to as “Cantor’s diagonal argument” and applies in more general contexts than we will see in these notes. Georg Cantor : born in St Petersburg (1845), died in Halle (1918) Theorem 42 The open interval (0,1) is not a countable set. Dr Rachel Quinlan MA180/MA186/MA190 Calculus R is uncountable 144 / 1712. If x ∉ S x ∉ S, then x ∈ g(x) = S x ∈ g ( x) = S, i.e., x ∈ S x ∈ S, a contradiction. Therefore, no such bijection is possible. Cantor's theorem implies that there are infinitely many infinite cardinal numbers, and that there is no largest cardinal number. It also has the following interesting consequence:Suggested for: Cantor diagonalization argument B I have an issue with Cantor's diagonal argument. Jun 6, 2023; Replies 6 Views 595. I Cantor's diagonalization on the rationals. Aug 18, 2021; Replies 25 Views 2K. B Another consequence of Cantor's diagonal argument. Aug 23, 2020; 2. Replies 43 Views 3K.

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History. Cantor believed the continuum hypothesis to be true and for many years tried in vain to prove it. It became the first on David Hilbert's list of important open questions that was presented at the International Congress of Mathematicians in the year 1900 in Paris. Axiomatic set theory was at that point not yet formulated. Kurt Gödel proved in 1940 that the negation of the continuum ...An octagon has 20 diagonals. A shape’s diagonals are determined by counting its number of sides, subtracting three and multiplying that number by the original number of sides. This number is then divided by two to equal the number of diagon...Cantor's diagonalization argument proves the real numbers are not countable, so no matter how hard we try to arrange the real numbers into a list, it can't be done. This also means that it is impossible for a computer program to loop over all the real numbers; any attempt will cause certain numbers to never be reached by the program.Hurkyl, every non-zero decimal digit can be any number between 1 to 9, Because I use Cantor's function where the rules are: A) Every 0 in the original diagonal number is turned to 1 in Cantor's new number. B) Every non-zero in the original diagonal number is turned to 0 in Cantor's new number.Cantor's diagonal argument, the rational open interv al (0, 1) would be non-denumerable, and we would ha ve a contradiction in set theory , because Cantor also prov ed the set of the rational ...For the Cantor argument, view the matrix a countable list of (countably) infinite sequences, then use diagonalization to build a SEQUENCE which does not occur as a row is the matrix. So the countable list of sequences (i.e. rows) is missing a sequence, so you conclude the set of all possible (infinite) sequences is UNCOUNTABLE.

Math 323: Homework 10 Solutions David Glickenstein April 4, 2013 8.9a) The set of polynomials with integer coe¢ cients is countable. Proof. First consider the set Pto which diagonalization can be seen as a constructive procedure that does the following: Given binary vectors v 1;v 2;:::, nd a binary vector u such that u 6= v j for all j. Moreover, notice that Cantor's diagonal argument involves querying only a single entry per each of the input vectors v j (i.e. the \diagonal" entries v j(j)). Thus, it ...Download this stock image: Cantor's infinity diagonalisation proof. Diagram showing how the German mathematician Georg Cantor (1845-1918) used a ...In my understanding of Cantor's diagonal argument, we start by representing each of a set of real numbers as an infinite bit string. My question is: why can't we begin by representing each natural number as an infinite bit string? So that 0 = 00000000000..., 9 = 1001000000..., 255 = 111111110000000...., and so on.Cantor's diagonalisation can be rephrased as a selection of elements from the power set of a set (essentially part of Cantor's Theorem). If we consider the set of (positive) reals as subsets of the naturals (note we don't really need the digits to be ordered for this to work, it just makes a simpler presentation) and claim there is a surjection ...In Section 1, starting from effective Cantor style diagonalizations, i.e., diagonalizations over recursively presentable classes, we introduce the framework within which our diagonalization concepts will be developed. In Section 2 we introduce our first concept: P-l-diagonalizations (2.1). We show thatCantor diagonalization. In 2008, David Wolpert used Cantor diagonalization to challenge the idea of Laplace's demon. He did this by assuming that the demon is a computational device and showed that no two such devices can completely predict each other.An intuitive explanation to Cantor's theorem which really emphasizes the diagonal argument. Reasons I felt like making this are twofold: I found other explan...4 Answers Sorted by: 3 The goal is to construct a number that isn't on the list (and thereby derive a contradiction). If we just pick some random row on our list, then …Isabelle: That seems to be a formalization of Cantor's powerset argument, not his diagonal argument. Overall, this highlights a major problem with formalization of existing proofs. There is no way (at least no obvious way) to "prove", that a formal proof X actually is a formalization of some informal proof Y. X could be simply a different proof ...Yes, because Cantor's diagonal argument is a proof of non existence. To prove that something doesn't, or can't, exist, you have two options: Check every possible thing that could be it, and show that none of them are, Assume that the thing does exist, and show that this leads to a contradiction of the original assertion.In set theory, Cantor's diagonal argument, also called the diagonalisation argument, the diagonal slash argument, the anti-diagonal argument, the diagonal method, and Cantor's diagonalization proof, was published in 1891 by Georg Cantor as a mathematical proof that there are infinite sets which cannot be put into one-to-one correspondence with the infinite set of natural numbers.

37) #13) In class we used a Cantor diagonalization argument to prove that the set of all infinite sequences of 0's and 1's is uncountable. Give another proof by identifying this set with set of all functions from N to {0, 1}, denoted {0,1}N, and using Problem 2(b) and part (a) of this problem.

One way to make this observation precise is via category theory, where we can observe that Cantor's theorem holds in an arbitrary topos, and this has the benefit of also subsuming a variety of other diagonalization arguments (e.g. the uncomputability of the halting problem and Godel's incompleteness theorem).Albert R Meyer, March 4, 2015 Cantor.1 Mathematics for Computer Science MIT 6.042J/18.062J Uncountable Sets . Albert R Meyer, March 4, 2015 . Cantor.2 . Infinite Sizes . Are all sets the same size? NO! Cantor's Theorem shows how to keep finding bigger infinities. Albert R Meyer, March 4, 2015 . Cantor.3 . Countable Sets1. Supply a rebuttal to the following complaint about Cantor's Diagonalization Argument, i.e., the proof that (0,1) is uncountable. Complaint. Every rational number has a decimal expansion so we could apply the Cantor Diagonalization Argument to show that the set of rational numbers between 0 and 1 is also uncountable.2023. 4. 5. ... Why Cantor's diagonal argument is logically valid?, Problems with Cantor's diagonal argument and uncountable infinity, Cantors diagonal ...1. I'm trying to show that the interval (0, 1) is uncountable and I want to verify that my proof is correct. My solution: Suppose by way of contradiction that (0, 1) is countable. Then we can create a one-to-one correspondence between N and (0, 1). 1 → 0.a0, 0 a0, 1 a0, 2 a0, 3…. 2 → 0.a1, 0 a1, 1 a1, 2 a1, 3…. 3 → 0.a2, 0 a2, 1 a2, 2 ...2. CANTOR'S PROOF. We begin by brie y recalling one version of the Cantor diagonalization proof (see [2, p. 43 ]). For simplicity we show that the interval [0 ;1] is not countable. Assume to the contrary that there is a sequence x 1;x2;x3;::: that contains all numbers in [0 ;1] and express x i as the decimal: x i = 0 :ai1 ai2 ai3:::$\begingroup$ The first part (prove (0,1) real numbers is countable) does not need diagonalization method. I just use the definition of countable sets - A set S is countable if there exists an injective function f from S to the natural numbers.The second part (prove natural numbers is uncountable) is totally same as Cantor's diagonalization method, the only difference is that I just remove "0."The Cantor set has many de nitions and many di erent constructions. Although Cantor originally provided a purely abstract de nition, the most accessible is the Cantor middle-thirds or ternary set construction. Begin with the closed real interval [0,1] and divide it into three equal open subintervals. Remove the central open interval I 1 = (1 3, 2 3Cantor's diagonalization proof shows that the real numbers aren't countable. It's a proof by contradiction. You start out with stating that the reals are countable. By our definition of "countable", this means that there must exist some order that you can list them all in.Cantor's diagonal proof is not infinite in nature, and neither is a proof by induction an infinite proof. For Cantor's diagonal proof (I'll assume the variant where we show the set of reals between $0$ and $1$ is uncountable), we have the following claims:

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However, when Cantor considered an infinite series of decimal numbers, which includes irrational numbers like π,eand √2, this method broke down.He used several clever arguments (one being the "diagonal argument" explained in the box on the right) to show how it was always possible to construct a new decimal number that was missing from the original list, and so proved that the infinity ...Hurkyl, every non-zero decimal digit can be any number between 1 to 9, Because I use Cantor's function where the rules are: A) Every 0 in the original diagonal number is turned to 1 in Cantor's new number. B) Every non-zero in the original diagonal number is turned to 0 in Cantor's new number.11. Diagonalization. Cantor’s proof is often referred to as “Cantor’s diagonalization argument.” Explain why this is a reasonable name. 12. Digging through diagonals. First, consider the following infinite collection of real numbers.The Cantor diagonal method, also called the Cantor diagonal argument or Cantor's diagonal slash, is a clever technique used by Georg Cantor to show that the …Upon applying the Cantor diagonal argument to the enumerated list of all computable numbers, we produce a number not in it, but seems to be computable too, and that seems paradoxical. For clarity, let me state the argument formally. It suffices to consider the interval [0,1] only. Consider 0 ≤ a ≤ 1 0 ≤ a ≤ 1, and let it's decimal ...1,398. 1,643. Question that occurred to me, most applications of Cantors Diagonalization to Q would lead to the diagonal algorithm creating an irrational number so not part of Q and no problem. However, it should be possible to order Q so that each number in the diagonal is a sequential integer- say 0 to 9, then starting over.Georg Waldemar Cantor was born in Denmark and he was a man with a deep love of culture and the arts. Georg's mother, Maria Anna Böhm, was Russian and very musical. Certainly Georg inherited considerable musical and artistic talents from his parents being an outstanding violinist. Georg was brought up a Protestant, this being the religion of ...Conjuntos gerais. A forma generalizada do argumento da diagonalização foi usado por Cantor para provar o teorema de Cantor: para cada conjunto S o conjunto das partes de S, ou seja, o conjunto de todos os subconjuntos de S (aqui escrito como P (S)), tem uma cardinalidade maior do que o próprio S. Esta prova é dada da seguinte forma: Seja f ...Wikipedia> Cantor's diagonal argument. Wikipedia Cantor's diagonal argument. January 06, 2023. This article is about a concept in set and number theory. Not to be confused with matrix diagonalization. See ... ….

showed that Z and Q are counatble, while Cantor diagonalization showed that R is uncountable. Countable and uncountable sets De nition. Let A be a non-empty set. (a)If there is a surjective function f: N !A, i.e., A can be written in roster notation as A = fa 0;a 1;a 2;:::g, then A is countable. (b)Otherwise, A is uncountable.Background. Let be the set of natural numbers.A first-order theory in the language of arithmetic represents the computable function : if there exists a "graph" formula (,) in the language of such that for each () [(() =) (,)]Here is the numeral corresponding to the natural number , which is defined to be the th successor of presumed first numeral in .. The diagonal lemma also …The graphical shape of Cantor's pairing function, a diagonal progression, is a standard trick in working with infinite sequences and countability. The algebraic rules of this diagonal-shaped function can verify its validity for a range of polynomials, of which a quadratic will turn out to be the simplest, using the method of induction. Indeed ...I have a feeling it will require using the Cantor Diagonalization method - but I'm not sure how you would use it for this problem. computation-theory; countable; Share. Improve this question. Follow edited Dec 10, 2018 at 12:39. Cœur. 37.4k 25 25 gold badges 196 196 silver badges 267 267 bronze badges.In his diagonal argument (although I believe he originally presented another proof to the same end) Cantor allows himself to manipulate the number he is checking for (as opposed to check for a fixed number such as $\pi$), and I wonder if that involves some meta-mathematical issues.. Let me similarly check whether a number I define is among the natural numbers.First, the original form of Cantor's diagonal argument is introduced. Second, it is demonstrated that any natural number is finite, by a simple mathematical induction. Third, the concept of ...It does this by listing real numbers and making a rule that its nth column cannot have a digit in the corresponding nth row. This produces a ...Na teoria dos conjuntos, o argumento da diagonalização de Cantor, também chamada de argumento da diagonalização, foi publicado em 1891 por Georg Cantor como uma prova matemática de que existem conjuntos infinitos que não podem ser mapeados em uma correspondência um-para-um ao conjunto infinito de números naturais. [1] [2] ... Cantor diagonalization, Cantor's diagonal argument in the end demonstrates "If the integers and the real numbers have the same cardinality, then we get a paradox". Note the big If in the first part. Because the paradox is conditional on the assumption that integers and real numbers have the same cardinality, that assumption must be false and integers and real numbers ..., Wikipedia> Cantor's diagonal argument. Wikipedia Cantor's diagonal argument. January 06, 2023. This article is about a concept in set and number theory. Not to be confused with matrix diagonalization. See ..., In set theory, Cantor's diagonal argument, also called the diagonalisation argument, the diagonal slash argument, the anti-diagonal argument, the diagonal method, and Cantor's diagonalization proof, was published in 1891 by Georg Cantor as a mathematical proof that there are infinite sets which cannot be put into one-to-one correspondence with ..., Cantor shocked the world by showing that the real numbers are not countable… there are “more” of them than the integers! His proof was an ingenious use of a proof by contradiction . In fact, he could show that there exists infinities of many different “sizes”!, The 1891 proof of Cantor's theorem for infinite sets rested on a version of his so-called diagonalization argument, which he had earlier used to prove that the cardinality of the rational numbers is the same as the cardinality of the integers by putting them into a one-to-one correspondence. The notion that, in the case of infinite sets, the size of a set could be the same as one of its ..., Cantor's diagonal argument is clearer in a more algebraic form. Suppose f is a 1-1 mapping between the positive integers and the reals. Let d n be the function that returns the n-th digit of a real number. Now, let's construct a real number, r.For the n-th digit of r, select something different from d n (f(n)), and not 0 or 9. Now, suppose f(m) = r.Then, the m-th digit of r must be d m (r) = d ..., Let S be the subset of T that is mapped by f (n). (By the assumption, it is an improper subset and S = T .) Diagonalization constructs a new string t0 that is in T, but not in S. Step 3 contradicts the assumption in step 1, so that assumption is proven false. This is an invalid proof, but most people don’t seem to see what is wrong with it., 5.3 Diagonalization The goal here is to develop a useful factorization A PDP 1, when A is n n. We can use this to compute Ak quickly for large k. The matrix D is a diagonal matrix (i.e. entries off the main diagonal are all zeros). Dk is trivial to compute as the following example illustrates. EXAMPLE: Let D 50 04. Compute D2 and D3., 11. I cited the diagonal proof of the uncountability of the reals as an example of a `common false belief' in mathematics, not because there is anything wrong with the proof but because it is commonly believed to be Cantor's second proof. The stated purpose of the paper where Cantor published the diagonal argument is to prove the existence of ..., We reprove that the set of real numbers is uncountable using the diagonalization argument of Cantor (1891). We then use this same style of proof to prove tha..., Suppose that, in constructing the number M in the Cantor diagonalization argument, we declare that. the first digit to the right of the decimal point of M will be 7, and then the other digits are selected. as before (if the second digit of the second real number has a 2, we make the second digit of M a 4; otherwise, we make the second digit a 2 ..., 4 Answers. Definition - A set S S is countable iff there exists an injective function f f from S S to the natural numbers N N. Cantor's diagonal argument - Briefly, the Cantor's diagonal argument says: Take S = (0, 1) ⊂R S = ( 0, 1) ⊂ R and suppose that there exists an injective function f f from S S to N N. We prove that there exists an s ..., This paper reveals why Cantor's diagonalization argument fails to prove what it purportedly proves and the logical absurdity of "uncountable sets" that are deemed larger than the set of natural numbers. Cantor's diagonalization, Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack Exchange, Return to Cantor's diagonal proof, and add to Cantor's 'diagonal rule' (R) the following rule (in a usual computer notation):. (R3) integer С; С := 1; for ..., Georg Waldemar Cantor was born in Denmark and he was a man with a deep love of culture and the arts. Georg's mother, Maria Anna Böhm, was Russian and very musical. Certainly Georg inherited considerable musical and artistic talents from his parents being an outstanding violinist. Georg was brought up a Protestant, this being the religion of ..., Figure 4.21 shows how this relates to the diagonalization technique. The complement of A TM is Unrecognizable. Definition: A language is co-Turing-recognizable if it is the complement of a Turing-recognizable language. Theorem: A language is decidable iff it is Turing-recognizable and co-Turing-recognizable. Proof: A TM is Turing-recognizable., Since Cantor Diagonalization Method [1] depicted that there are uncountably and infinitely many real numbers in [a, b], and and are functions by extreme value the orem [ 2 ], A few pages in, the author claims that closed balls are both open and compact sets in the p -adic topology on Qp. I have not been able to verify this, and would like to understand it before proceeding further. For clarity, let a closed ball B(x, r) = {y ∈ Qp: | x − y | p ≤ p − r}. Then why is B(x, r) both open and compact in the p -adic ..., $\begingroup$ The idea of "diagonalization" is a bit more general then Cantor's diagonal argument. What they have in common is that you kind of have a bunch of things indexed by two positive integers, and one looks at those items indexed by pairs $(n,n)$. The "diagonalization" involved in Goedel's Theorem is the Diagonal Lemma., 37) #13) In class we used a Cantor diagonalization argument to prove that the set of all infinite sequences of 0's and 1's is uncountable. Give another proof by identifying this set with set of all functions from N to {0, 1}, denoted {0,1}N, and using Problem 2(b) and part (a) of this problem., The diagonal process was first used in its original form by G. Cantor. in his proof that the set of real numbers in the segment $ [ 0, 1 ] $ is not countable; the process is therefore also known as Cantor's diagonal process. A second form of the process is utilized in the theory of functions of a real or a complex variable in order to isolate ..., Abstract. We examine Cantor's Diagonal Argument (CDA). If the same basic assumptions and theorems found in many accounts of set theory are applied with a standard combinatorial formula a ..., Cantor's diagonalization is a way of creating a unique number given a countable list of all reals. I can see how Cantor's method creates a unique decimal string but I'm unsure if this decimal string corresponds to a unique number. Essentially this is because $1 = 0.\overline{999}$. Consider the list which contains all real numbers between $0 ..., A nonagon, or enneagon, is a polygon with nine sides and nine vertices, and it has 27 distinct diagonals. The formula for determining the number of diagonals of an n-sided polygon is n(n – 3)/2; thus, a nonagon has 9(9 – 3)/2 = 9(6)/2 = 54/..., Mar 6, 2022 · Cantor’s diagonal argument. The person who first used this argument in a way that featured some sort of a diagonal was Georg Cantor. He stated that there exist no bijections between infinite sequences of 0’s and 1’s (binary sequences) and natural numbers. In other words, there is no way for us to enumerate ALL infinite binary sequences. , Since there are countably many computable real numbers (see Alex's answer), our listing of "all the real numbers" may in fact include each of these without any problem. However, when you apply Cantor's diagonalisation argument to this list, you get a real number that is not on the list, and must therefore be uncomputable., The Cantor diagonal method, also called the Cantor diagonal argument or Cantor's diagonal slash, is a clever technique used by Georg Cantor to show that the integers and reals cannot be put into a one-to-one correspondence (i.e., the uncountably infinite set of real numbers is "larger" than the countably infinite set …, From Cantor's diagonalization proof, he showed that some infinities are larger than others. Is it possible that the universe which I am supposing is infinite in size is a larger infinity than the infinite matter-energy in the universe? Don't mix mathematical concepts with physical ones here. Cantor's proof is about sets of numbers and that's all., If a second grader were able to show an argument that something is wrong with Cantor's diagonalization, it would be no less true than if a PhD from the best university in the world made the same ..., Because the decimal expansion of any rational repeats, and the diagonal construction of x x does not repeat, and thus is not rational. There is no magic to the specific x x we picked; it would just as well to do a different base, like binary. x_1 = \sum_ {n \in \mathbb N} \Big ( 1 - \big\lfloor f' (n) 2^ {n}\big\rfloor\Big) 2^ {-n} x1 = n∈N ..., Euler, Newton, Gauss (order depending on the area of math in which you’re interested), Cantor (diagonalization IS computation, encompassing Turing and the nature of infinite sets/languages), Riemann/Cauchy (geometry/complex analysis respectively, basically foundations for all modern physics), 2. If x ∉ S x ∉ S, then x ∈ g(x) = S x ∈ g ( x) = S, i.e., x ∈ S x ∈ S, a contradiction. Therefore, no such bijection is possible. Cantor's theorem implies that there are infinitely many infinite cardinal numbers, and that there is no largest cardinal number. It also has the following interesting consequence: