James A. D. W. Anderson

Last updated

James A. D. W. Anderson
Born1958 (age 6364)
Alma mater University of Reading
Known forComputer algebra
Division by zero
Transreal arithmetic
Scientific career
Institutions University of Reading
Doctoral advisor Geoffrey Daniel Sullivan

James Arthur Dean Wallace Anderson, known as James Anderson, is a retired member of academic staff in the School of Systems Engineering at the University of Reading, England, where he used to teach compilers, algorithms, fundamentals of computer science and computer algebra, programming and computer graphics. [1]

Contents

Anderson quickly gained publicity in December 2006 in the United Kingdom when the regional BBC South Today reported his claim of "having solved a 1200 year old problem", namely that of division by zero. However, commentators quickly responded that his ideas are just a variation of the standard IEEE 754 concept of NaN (Not a Number), which has been commonly employed on computers in floating point arithmetic for many years. [2]

Dr Anderson defended against the criticism of his claims on BBC Berkshire on 12 December 2006, saying, "If anyone doubts me I can hit them over the head with a computer that does it." [3]

Anderson was banned from teaching transreal arithmetic at the University of Reading in 2019 when he was reported to have been teaching it during a class "Fundamentals of Computer Science". Anderson's nullity and transreal arithmetic are unaccepted by mathematicians and computer scientists alike, and is not a fundamental part of computer science. Shortly after, he quit, around the end of 2019. [ citation needed ]

Research and background

Anderson was a member of the British Computer Society, the British Machine Vision Association, Eurographics, and the British Society for the Philosophy of Science. [4] He was also a teacher in the Computer Science department (School of Systems Engineering) at the University of Reading. [1] He was a psychology graduate who worked in the Electrical and Electronic Engineering departments at the University of Sussex and Plymouth Polytechnic (now the University of Plymouth). His doctorate is from the University of Reading for (in Anderson's words) "developing a canonical description of the perspective transformations in whole numbered dimensions".

He has written multiple papers on division by zero [5] [6] and has invented what he calls the "Perspex machine".

Anderson claims that "mathematical arithmetic is sociologically invalid" and that IEEE floating-point arithmetic, with NaN, is also faulty. [7]

Transreal arithmetic

Zero divided by zero
In mathematical analysis, the following limits can be found:

is also an indeterminate form. See exponentiation.

In IEEE floating-point arithmetic:
by definition

In several computer programming languages, including C's pow function, is defined to be , as that is the most convenient value for numerical analysis programs, since it makes (and many other functions) continuous at zero, with the notable exception of . [8]

In transreal arithmetic:
by definition
by Anderson's proof, reported on by the BBC, that:

Anderson's transreal numbers were first mentioned in a 1997 publication, [9] and made well known on the Internet in 2006, but not accepted as useful by the mathematics community. These numbers are used in his concept of transreal arithmetic and the Perspex machine. According to Anderson, transreal numbers include all of the real numbers, plus three others: infinity (), negative infinity () and "nullity" (), a number that lies outside the affinely extended real number line. (Nullity, confusingly, has an existing mathematical meaning.)

Anderson intends the axioms of transreal arithmetic to complement the axioms of standard arithmetic; they are supposed to produce the same result as standard arithmetic for all calculations where standard arithmetic defines a result. In addition, they are intended to define a consistent numeric result for the calculations which are undefined in standard arithmetic, such as division by zero. [10]

Transreal arithmetic and other arithmetics

"Transreal arithmetic" is derived from projective geometry [9] but produces results similar to IEEE floating point arithmetic, a floating point arithmetic commonly used on computers. IEEE floating point arithmetic, like transreal arithmetic, uses affine infinity (two separate infinities, one positive and one negative) rather than projective infinity (a single unsigned infinity, turning the number line into a loop).

Here are some identities in transreal arithmetic with the IEEE equivalents:

Transreal arithmeticIEEE standard floating point arithmetic
( may or may not be identical)
( may or may not be identical)
(i.e. applying unary negation to a NaN yields the identical NaN)

The main difference is that IEEE arithmetic replaces the real (and transreal) number zero with positive and negative zero. (This is so that it can preserve the sign of a nonzero real number whose absolute value has been rounded down to zero. See also infinitesimal.) Division of any non-zero finite number by zero results in either positive or negative infinity.

Another difference between transreal and IEEE floating-point operations is that nullity compares equal to nullity, whereas NaN does not compare equal to NaN. This is due to nullity being a number, whereas NaN is an indeterminate value. It is easy to see that nullity is not an indeterminate value. For example, the numerator of nullity is zero, but the numerator of an indeterminate value is indeterminate. Thus nullity and indeterminant have different properties, which is to say they are not the same! In IEEE, the inequality is because two expressions which both fail to have a numerical value cannot be numerically equivalent.

Anderson's analysis of the properties of transreal algebra is given in his paper on "perspex machines". [11]

Due to the more expansive definition of numbers in transreal arithmetic, several identities and theorems which apply to all numbers in standard arithmetic are not universal in transreal arithmetic. For instance, in transreal arithmetic, is not true for all , since . That problem is addressed in ref. [11] pg. 7. Similarly, it is not always the case in transreal arithmetic that a number can be cancelled with its reciprocal to yield . Cancelling zero with its reciprocal in fact yields nullity.

Examining the axioms provided by Anderson, [10] it is easy to see that any arithmetical term, being a sum, difference, product, or quotient, which contains an occurrence of the constant is provably equivalent to . This is to say that nullity is absorptive over these arithmetical operations. Formally, let be any arithmetical term with a sub-arithmetical-term , then is a theorem of the theory proposed by Anderson.

Media coverage

Anderson's transreal arithmetic, and concept of "nullity" in particular, were introduced to the public by the BBC with its report in December 2006 [5] where Anderson was featured on a BBC television segment teaching schoolchildren about his concept of "nullity". The report implied that Anderson had discovered the solution to division by zero, rather than simply attempting to formalize it. The report also suggested that Anderson was the first to solve this problem, when in fact the result of zero divided by zero has been expressed formally in a number of different ways (for example, NaN).

The BBC was criticized for irresponsible journalism, but the producers of the segment defended the BBC, stating that the report was a light-hearted look at a mathematical problem aimed at a mainstream, regional audience for BBC South Today rather than at a global audience of mathematicians. The BBC later posted a follow-up giving Anderson's response to many claims that the theory is flawed. [3]

Applications

Anderson has been trying to market his ideas for transreal arithmetic and "Perspex machines" to investors. He claims that his work can produce computers which run "orders of magnitude faster than today's computers". [7] [12] He has also claimed that it can help solve such problems as quantum gravity, [7] the mind-body connection, [13] consciousness [13] and free will. [13]

See also

Related Research Articles

An axiom, postulate, or assumption is a statement that is taken to be true, to serve as a premise or starting point for further reasoning and arguments. The word comes from the Ancient Greek word ἀξίωμα (axíōma), meaning 'that which is thought worthy or fit' or 'that which commends itself as evident'.

<span class="mw-page-title-main">Floating-point arithmetic</span> Computer approximation for real numbers

In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can be represented as a base-ten floating-point number:

IEEE 754-1985 was an industry standard for representing floating-point numbers in computers, officially adopted in 1985 and superseded in 2008 by IEEE 754-2008, and then again in 2019 by minor revision IEEE 754-2019. During its 23 years, it was the most widely used format for floating-point computation. It was implemented in software, in the form of floating-point libraries, and in hardware, in the instructions of many CPUs and FPUs. The first integrated circuit to implement the draft of what was to become IEEE 754-1985 was the Intel 8087.

<span class="mw-page-title-main">Multiplication</span> Arithmetical operation

Multiplication is one of the four elementary mathematical operations of arithmetic, with the other ones being addition, subtraction, and division. The result of a multiplication operation is called a product.

In mathematical logic, the Peano axioms, also known as the Dedekind–Peano axioms or the Peano postulates, are axioms for the natural numbers presented by the 19th century Italian mathematician Giuseppe Peano. These axioms have been used nearly unchanged in a number of metamathematical investigations, including research into fundamental questions of whether number theory is consistent and complete.

In computing, NaN, standing for Not a Number, is a member of a numeric data type that can be interpreted as a value that is undefined or unrepresentable, especially in floating-point arithmetic. Systematic use of NaNs was introduced by the IEEE 754 floating-point standard in 1985, along with the representation of other non-finite quantities such as infinities.

Double-precision floating-point format is a floating-point number format, usually occupying 64 bits in computer memory; it represents a wide dynamic range of numeric values by using a floating radix point.

In classical deductive logic, a consistent theory is one that does not lead to a logical contradiction. The lack of contradiction can be defined in either semantic or syntactic terms. The semantic definition states that a theory is consistent if it has a model, i.e., there exists an interpretation under which all formulas in the theory are true. This is the sense used in traditional Aristotelian logic, although in contemporary mathematical logic the term satisfiable is used instead. The syntactic definition states a theory is consistent if there is no formula such that both and its negation are elements of the set of consequences of . Let be a set of closed sentences and the set of closed sentences provable from under some formal deductive system. The set of axioms is consistent when for no formula .

<span class="mw-page-title-main">Rounding</span> Replacing a number with a simpler value

Rounding means replacing a number with an approximate value that has a shorter, simpler, or more explicit representation. For example, replacing $23.4476 with $23.45, the fraction 312/937 with 1/3, or the expression 2 with 1.414.

<span class="mw-page-title-main">Division by zero</span> Class of mathematical expression

In mathematics, division by zero is division where the divisor (denominator) is zero. Such a division can be formally expressed as , where a is the dividend (numerator). In ordinary arithmetic, the expression has no meaning, as there is no number that, when multiplied by 0, gives a ; thus, division by zero is undefined. Since any number multiplied by zero is zero, the expression is also undefined; when it is the form of a limit, it is an indeterminate form. Historically, one of the earliest recorded references to the mathematical impossibility of assigning a value to is contained in Anglo-Irish philosopher George Berkeley's criticism of infinitesimal calculus in 1734 in The Analyst.

In axiomatic set theory and the branches of mathematics and philosophy that use it, the axiom of infinity is one of the axioms of Zermelo–Fraenkel set theory. It guarantees the existence of at least one infinite set, namely a set containing the natural numbers. It was first published by Ernst Zermelo as part of his set theory in 1908.

The IEEE Standard for Floating-Point Arithmetic is a technical standard for floating-point arithmetic established in 1985 by the Institute of Electrical and Electronics Engineers (IEEE). The standard addressed many problems found in the diverse floating-point implementations that made them difficult to use reliably and portably. Many hardware floating-point units use the IEEE 754 standard.

Internal set theory (IST) is a mathematical theory of sets developed by Edward Nelson that provides an axiomatic basis for a portion of the nonstandard analysis introduced by Abraham Robinson. Instead of adding new elements to the real numbers, Nelson's approach modifies the axiomatic foundations through syntactic enrichment. Thus, the axioms introduce a new term, "standard", which can be used to make discriminations not possible under the conventional ZFC axioms for sets. Thus, IST is an enrichment of ZFC: all axioms of ZFC are satisfied for all classical predicates, while the new unary predicate "standard" satisfies three additional axioms I, S, and T. In particular, suitable nonstandard elements within the set of real numbers can be shown to have properties that correspond to the properties of infinitesimal and unlimited elements.

In mathematical logic, New Foundations (NF) is an axiomatic set theory, conceived by Willard Van Orman Quine as a simplification of the theory of types of Principia Mathematica. Quine first proposed NF in a 1937 article titled "New Foundations for Mathematical Logic"; hence the name. Much of this entry discusses NFU, an important variant of NF due to Jensen (1969) and clarified by Holmes (1998). In 1940 and in a revision in 1951, Quine introduced an extension of NF sometimes called "Mathematical Logic" or "ML", that included proper classes as well as sets.

The term arithmetic underflow is a condition in a computer program where the result of a calculation is a number of more precise absolute value than the computer can actually represent in memory on its central processing unit (CPU).

In mathematics, Robinson arithmetic is a finitely axiomatized fragment of first-order Peano arithmetic (PA), first set out by R. M. Robinson in 1950. It is usually denoted Q. Q is almost PA without the axiom schema of mathematical induction. Q is weaker than PA but it has the same language, and both theories are incomplete. Q is important and interesting because it is a finitely axiomatized fragment of PA that is recursively incompletable and essentially undecidable.

In mathematical logic, Heyting arithmetic is an axiomatization of arithmetic in accordance with the philosophy of intuitionism. It is named after Arend Heyting, who first proposed it.

Signed zero is zero with an associated sign. In ordinary arithmetic, the number 0 does not have a sign, so that −0, +0 and 0 are identical. However, in computing, some number representations allow for the existence of two zeros, often denoted by −0 and +0, regarded as equal by the numerical comparison operations but with possible different behaviors in particular operations. This occurs in the sign and magnitude and ones' complement signed number representations for integers, and in most floating-point number representations. The number 0 is usually encoded as +0, but can be represented by either +0 or −0.

Single-precision floating-point format is a computer number format, usually occupying 32 bits in computer memory; it represents a wide dynamic range of numeric values by using a floating radix point.

<span class="mw-page-title-main">Division by infinity</span>

In mathematics, division by infinity is division where the divisor (denominator) is infinity. In ordinary arithmetic, this does not have a well-defined meaning, since infinity is a mathematical concept that does not correspond to a specific number, and moreover, there is no nonzero real number that, when added to itself an infinite number of times, gives a finite number. However, "dividing by infinity" can be given meaning as an informal way of expressing the limit of dividing a number by larger and larger divisors.

References

  1. 1 2 "Computer Science at Reading - Dr. James Anderson". University of Reading . Retrieved 28 February 2011.
  2. Mark C. Chu-Carroll (7 December 2006). "Nullity: The Nonsense Number". Good Math, Bad Math. Archived from the original on 9 December 2006. Retrieved 7 December 2006.
  3. 1 2 "Nullity is a number, and that makes a difference". BBC News . 12 December 2006. Retrieved 12 December 2006.
  4. "About the Ambient & Pervasive Intelligence Research Group". University of Reading . Retrieved 16 January 2007.
  5. 1 2 Ben Moore; Ollie Williams (7 December 2006). "1200-year-old problem "easy"". BBC News . Schoolchildren from Caversham have become the first to learn a brand new theory that dividing by zero is possible using a new number—"nullity". But the suggestion has left many mathematicians cold..
  6. "Professor Comes Up With a Way to Divide by Zero". Slashdot . Retrieved 7 December 2006.
  7. 1 2 3 Dr James A.D.W. Anderson. "Transreal Computing Research and Portfolio – Company Showcase" (PDF). Archived from the original (PDF) on 23 January 2007. Retrieved 11 December 2006.
  8. John Benito (April 2003). "Rationale for International Standard – Programming Languages – C" (PDF). Revision 5.10: 182.{{cite journal}}: Cite journal requires |journal= (help)
  9. 1 2 Anderson, James A. D. W. (1997). "Representing Geometrical Knowledge". Philosophical Transactions of the Royal Society of London, Series B. 352 (1358): 1129–39. Bibcode:1997RSPTB.352.1129A. doi:10.1098/rstb.1997.0096. PMC   1692011 . PMID   9304680.
  10. 1 2 J. A. D. W. Anderson (2006). "Perspex Machine VIII: Axioms of Transreal Arithmetic" (PDF). In Longin Jan Latecki; David M. Mount; Angela Y. Wu (eds.). Vision Geometry XV: Proceedings of SPIE. Vol. 6499.
  11. 1 2 J. A. D. W. Anderson (2006). "Perspex Machine IX: Transreal Analysis" (PDF). In Longin Jan Latecki; David M. Mount; Angela Y. Wu. (eds.). Vision Geometry XV: Proceedings of SPIE. Vol. 6499.
  12. "Transreal Computing Ltd". Archived from the original on 8 January 2007. Retrieved 12 December 2006.
  13. 1 2 3 "Home". bookofparagon.com.

Further reading