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Sava Grozdev and Deko Dekov, a Survey of Mathematics Discovered International Journal of Computer Discovered Mathematics (IJCDM) ISSN 2367-7775 c IJCDM November 2015, Volume 0, No.0, pp.3-20. Received 15 August 2015. Published on-line 15 September 2015 web: http://www.journal-1.eu/ c The Author(s) This article is published with open access1. A Survey of Mathematics Discovered by Computers Sava Grozdeva and Deko Dekovb2 a VUZF University of Finance, Business and Entrepreneurship, Gusla Street 1, 1618 Sofia, Bulgaria e-mail: [email protected] bZahari Knjazheski 81, 6000 Stara Zagora, Bulgaria e-mail: [email protected] web: http://www.ddekov.eu/ Abstract. This survey presents results in mathematics discovered by computers. Keywords. mathematics discovered by computers, computer-discoverer, Eu- clidean geometry, triangle geometry, remarkable point, “Discoverer”. Mathematics Subject Classification (2010). 51-04, 68T01, 68T99. 1. Introduction This survey presents some results in mathematics discovered by computers. We could not find (March 2015) in the literature new theorems in mathematics, dis- covered by computers, different from the results discovered by the “Discoverer”. Hence, we present some results discovered by the computer program “Discoverer”. The computer program “Discoverer” is the first computer program, able easily to discover new theorems in mathematics, and possibly, the first computer program, able easily to discover new knowledge in science. The creation of the computer program “Discoverer” began in June 2012. The “Discoverer” is created by the authors - Sava Grozdev and Deko Dekov. In 2006 was created the prototype of the “Discoverer”, named the “Machine for Questions nd Answers”. The prototype has discovered a few thousands new theorems. The prototype of the “Discoverer” has been created by using the JavaScript. The “Discoverer” is created by using PHP and MySQL. 1This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. 2Corresponding author 3 4 A Survey of Mathematics Discovered by Computers The reader may find description of the “Discoverer” in the paper [20]. The “Discoverer” produces theorems by using natural language. The reader could use the theorems without changes. The “Discoverer” is a module system. Each module is independent from the others. Each module can be independently im- proved and extended. Also, we could add easily new modules. Hence, the “Dis- coverer” could be easily improved and extended, and any further extension will make it better. The “Discoverer” is in an early stage of development. We invite the interested persons and institutions to join the team and to work together with us on the “Discoverer”. In this survey we present some results discovered by the “Discoverer”. The reader interested better to understand the “Discoverer” has to read the Grozdev-Dekov papers. The results included in this paper present a small part of the abilities of the “Discoverer”. We hope that the included results will give to the reader the possibility to feel the flower of the “Discoverer”. For complete description of the abilities of the “Discoverer” the reader has to consult the Discoverer User Manual. The ideas of the “Discoverer” are effectively applicable in other areas of science, like biotechnology, medicine, biology, chemistry, physics, risk management, and so on. No doubt that the applications of the “Discoverer” in these areas will discover essential new results. Moreover, the “Discoverer” has the potential to extend a few times the current science. In Grozdev-Dekov papers the reader often will hear about barycentric coordinates. The homogeneous barycentric coordinates of a point are denoted (u : v : w). In the Grozdev-Dekov papers the same coordinates are named barycentric coordinates and are denoted by (u; v; w). In this journal the reader may see an introduc- tory paper about the barycentric coordinates by Francisco Javier Garc´ia Capit´an [5]. For more information about barycentric coordinates we refer the reader to [5],[73],[74],[2],[65], [66],[48],[48]. See also [54], Glossary. For some info about the Artificial Intelligence we refer the reader to [63],[64]. 2. The Simon-Newell prediction In 1958, in a seminal paper predicting future successes of artificial intelligence and operational research, Herbert Simon and Alan Newell [69] suggested that: “Within ten years a digital computer will discover an important mathematical theorem”. 3. The Paulson Criterion We need a criterion for possible realization of the Simon-Newell prediction. There are a few criteria. Below we consider the Paulson criterion. The Paulson criterion is as follows [67]: In order a theorem in mathematics to be accepted as a theorem discovered by a computer, the following data has to be published in a mathematical journal: (1) The statement of the theorem. (2) A statement that the result is discovered by a computer. (3) Direct or indirect statement that the theorem is new, not published before. Grozdev and Dekov 5 (4) The name of the computer program which has discovered the result. (5) The name of the authors who have created the computer program. The Strong Paulson criterion is as follows: The Paulson criterion plus (6) The basic ideas of the computer program have to be published. (7) If a number of theorems are published by the creators of the computer program, it should be clear that the theorems are not discovered by the people. The computer program “Discoverer” satisfies the Strong Paulson criterion. Note that description of “Discoverer” is published in [20]. Simon and Newell speak about “important” theorem. The criterion about impor- tance is not clear. We accept the following criterion: A new theorem is “important” if it generalizes published theorems, or it improves published theorems. Clearly, if a theorem solves a hypothesis, it also should be considered as “important”, but we do not include this case, because we speak about theorems whose statements are not known in advance. The computer program “Discoverer” satisfies the above criterion for “importance”. In March 2015 the predecessor of this journal, the “International Journal of Com- puter Generated Mathematics”, announced inquiry about the realization of the Simon-Newell prediction. About 50 experts in the area of the AI have been in- vited to submit a theorem which satisfies the Paulson criterion. The result of the inquiry is as follows: The number of theorems which satisfy the Paulsen crite- rion is zero (except for the theorems discovered by the “Discoverer”). The inquiry proved that the only computer program which is a candidate for realization of the Simon-Newell prediction is the “Discoverer”. The “Discoverer” realizes the Simon-Newell prediction. See [28] and the Grozdev-Dekov papers. Note that currently there are more than 100 papers containing approximately 10 000 new theorems discovered by the “Discoverer” and its prototype. The current capacity of the “Discoverer” is approximately 500 000 new theorems. After the next extension of the “Discoverer”, it is expected that it will be able to discover a few millions new theorems. But the value of the “Discoverer” is not in the number of discovered theorems. Simon and Newell speak about a separate theorem. The “Discoverer” discovers theories. See [14] and other Grozdev-Dekov papers. 4. The "Discoverer" improves the Steiner’s Construction of the Malfatti Circles The construction of the Malfatti circles is one of the famous mathematical prob- lems. The problem was posed by the Italian geometer Gian Francesco Malfatti in 1803 [60]. A simple construction with compass and ruler of the Malfatti circles has been published by the great Swiss geometer Jacob Steiner in 1826. [72], Mal- fatti circles, [70]. As far as the authors know, the improvement of the Steiner’s construction of the Malfatti circles, discovered by the “Discoverer” [25], is the first essential improvement of an important result in mathematics, discovered by a computer, and possibly, the first improvement of an important result in science, discovered by a computer. 6 A Survey of Mathematics Discovered by Computers C C OC VB I VA OA OB VC A B A B Figure 1 Figure 2 Given triangle ABC. The Malfatti circles are three circles inside a given triangle such that each circle is tangent to the other two and to two sides of the triangle. We denote by OA;OB and OC the centers of the Malfatti circles inscribed in angles A; B and C, respectively. The triangle OAOBOC is known as the Malfatti central triangle. Figure 1 illustrates the Malfatti circles and the Malfatti central triangle. Let I be the incenter of 4ABC and let VA;VB and VC be the incenters of the incircles c1; c2 and c3, inscribed in triangles BCI; CAI and ABI, respectively. Recall that 4VAVBVC is known as the de Villiers triangle. Figure 2 illustrates the de Viliers triangle. The mutual internal tangents to the circles c1; c2 and c3 concur in a point S, known as the Malfatti-Steiner Point. The Steiner’s construction of the Malfatti circles has the following five stages: Stage 1. Construct the internal angle bisectors and the incenter of 4ABC. Stage 2. Construct the de Villiers triangle. Stage 3. Construct the Malfatti-Steiner point S. Stage 4. Construct the Malfatti central triangle. Stage 5. Construct the Malfatti circles. The computer program “Discoverer” has discovered a number of theorems related to the Malfatti circles. Below we give three of these theorems [7]: Theorem 4.1. The Malfatti-Steiner Point is the Isogonal Conjugate of the In- C center with respect to the de Villiers Tri- angle. OC VB Theorem 4.2. The Malfatti-Steiner S VA Point is the Second Kenmotu Point of the I OA de Villiers Triangle. OB VC Theorem 4.3. The Malfatti-Steiner A B Point is the Perspector of the Malfatti Central Triangle and the de Villiers Tri- Figure 3 angle.
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