A Multi Foci Closed Curve: Cassini Oval, Its Properties and Applications
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
[Math.AG] 1 Nov 2005 Where Uoopimgop Hscntuto Ensahlmrhcperio Holomorphic a Defines Construction This Group
A COMPACTIFICATION OF M3 VIA K3 SURFACES MICHELA ARTEBANI Abstract. S. Kond¯odefined a birational period map from the moduli space of genus three curves to a moduli space of degree four polarized K3 surfaces. In this paper we extend the period map to a surjective morphism on a suitable compactification of M3 and describe its geometry. Introduction 14 Let V =| OP2 (4) |=∼ P be the space of plane quartics and V0 be the open subvariety of smooth curves. The degree four cyclic cover of the plane branched along a curve C ∈ V0 is a K3 surface equipped with an order four non-symplectic automorphism group. This construction defines a holomorphic period map: P0 : V0 −→ M, where V0 is the geometric quotient of V0 by the action of P GL(3) and M is a moduli space of polarized K3 surfaces. In [15] S. Kond¯oshows that P0 gives an isomorphism between V0 and the com- plement of two irreducible divisors Dn, Dh in M. Moreover, he proves that the generic points in Dn and Dh correspond to plane quartics with a node and to smooth hyperelliptic genus three curves respectively. The moduli space M is an arithmetic quotient of a six dimensional complex ball, hence a natural compactification is given by the Baily-Borel compactification M∗ (see [1]). On the other hand, geometric invariant theory provides a compact pro- jective variety V containing V0 as a dense subset, given by the categorical quotient of the semistable locus in V for the natural action of P GL(3). In this paper we prove that the map P0 can be extended to a holomorphic surjective map P : V −→M∗ on the blowing-up V of V in the point v0 corresponding to the orbit of double arXiv:math/0511031v1 [math.AG] 1 Nov 2005 e conics. -
Shadow of a Cubic Surface
Faculteit B`etawetenschappen Shadow of a cubic surface Bachelor Thesis Rein Janssen Groesbeek Wiskunde en Natuurkunde Supervisors: Dr. Martijn Kool Departement Wiskunde Dr. Thomas Grimm ITF June 2020 Abstract 3 For a smooth cubic surface S in P we can cast a shadow from a point P 2 S that does not lie on one of the 27 lines of S onto a hyperplane H. The closure of this shadow is a smooth quartic curve. Conversely, from every smooth quartic curve we can reconstruct a smooth cubic surface whose closure of the shadow is this quartic curve. We will also present an algorithm to reconstruct the cubic surface from the bitangents of a quartic curve. The 27 lines of S together with the tangent space TP S at P are in correspondence with the 28 bitangents or hyperflexes of the smooth quartic shadow curve. Then a short discussion on F-theory is given to relate this geometry to physics. Acknowledgements I would like to thank Martijn Kool for suggesting the topic of the shadow of a cubic surface to me and for the discussions on this topic. Also I would like to thank Thomas Grimm for the suggestions on the applications in physics of these cubic surfaces. Finally I would like to thank the developers of Singular, Sagemath and PovRay for making their software available for free. i Contents 1 Introduction 1 2 The shadow of a smooth cubic surface 1 2.1 Projection of the first polar . .1 2.2 Reconstructing a cubic from the shadow . .5 3 The 27 lines and the 28 bitangents 9 3.1 Theorem of the apparent boundary . -
Combination of Cubic and Quartic Plane Curve
IOSR Journal of Mathematics (IOSR-JM) e-ISSN: 2278-5728,p-ISSN: 2319-765X, Volume 6, Issue 2 (Mar. - Apr. 2013), PP 43-53 www.iosrjournals.org Combination of Cubic and Quartic Plane Curve C.Dayanithi Research Scholar, Cmj University, Megalaya Abstract The set of complex eigenvalues of unistochastic matrices of order three forms a deltoid. A cross-section of the set of unistochastic matrices of order three forms a deltoid. The set of possible traces of unitary matrices belonging to the group SU(3) forms a deltoid. The intersection of two deltoids parametrizes a family of Complex Hadamard matrices of order six. The set of all Simson lines of given triangle, form an envelope in the shape of a deltoid. This is known as the Steiner deltoid or Steiner's hypocycloid after Jakob Steiner who described the shape and symmetry of the curve in 1856. The envelope of the area bisectors of a triangle is a deltoid (in the broader sense defined above) with vertices at the midpoints of the medians. The sides of the deltoid are arcs of hyperbolas that are asymptotic to the triangle's sides. I. Introduction Various combinations of coefficients in the above equation give rise to various important families of curves as listed below. 1. Bicorn curve 2. Klein quartic 3. Bullet-nose curve 4. Lemniscate of Bernoulli 5. Cartesian oval 6. Lemniscate of Gerono 7. Cassini oval 8. Lüroth quartic 9. Deltoid curve 10. Spiric section 11. Hippopede 12. Toric section 13. Kampyle of Eudoxus 14. Trott curve II. Bicorn curve In geometry, the bicorn, also known as a cocked hat curve due to its resemblance to a bicorne, is a rational quartic curve defined by the equation It has two cusps and is symmetric about the y-axis. -
FINITE FOURIER SERIES and OVALS in PG(2, 2H)
J. Aust. Math. Soc. 81 (2006), 21-34 FINITE FOURIER SERIES AND OVALS IN PG(2, 2h) J. CHRIS FISHERY and BERNHARD SCHMIDT (Received 2 April 2004; revised 7 May 2005) Communicated by L. Batten Abstract We propose the use of finite Fourier series as an alternative means of representing ovals in projective planes of even order. As an example to illustrate the method's potential, we show that the set [w1 + wy' + w ~y' : 0 < j < 2;'| c GF(22/1) forms an oval if w is a primitive (2h + l)sl root of unity in GF(22'') and GF(22'') is viewed as an affine plane over GF(2;'). For the verification, we only need some elementary 'trigonometric identities' and a basic irreducibility lemma that is of independent interest. Finally, we show that our example is the Payne oval when h is odd, and the Adelaide oval when h is even. 2000 Mathematics subject classification: primary 51E20, 05B25. 1. Introduction In any finite projective plane of order q, an oval is a set of q + 1 points, no three of which are collinear. In the classical plane PG(2, q) over GF(g), a nondegenerate conic is the prototypical oval. If the order of a plane is even, then the tangents to an oval all pass through a point that is called the nucleus of the oval. We call an oval together with its nucleus a hyperoval. During the 1950s Beniamino Segre proved that in PG(2, q), (1) when q is odd, then there exist no ovals other than the conies, and (2) when q — 2\ coordinates may be chosen so that the points of a hyperoval are the elements of the set {(*, f{x), 1) | JC G GF(<?)} U {(0, 1,0), (1,0, 0)}, where / is a permutation polynomial of degree at most q — 2 for which /(0) = 0, /(I) = 1, and with the additional property that for all 5 in GF(^), the function /,. -
Parametric Representations of Polynomial Curves Using Linkages
Parabola Volume 52, Issue 1 (2016) Parametric Representations of Polynomial Curves Using Linkages Hyung Ju Nam1 and Kim Christian Jalosjos2 Suppose that you want to draw a large perfect circle on a piece of fabric. A simple technique might be to use a length of string and a pen as indicated in Figure1: tie a knot at one end (A) of the string, push a pin through the knot to make the center of the circle, tie a pen at the other end (B) of the string, and rotate around the pin while holding the string tight. Figure 1: Drawing a perfect circle Figure 2: Pantograph On the other hand, you may think about duplicating or enlarging a map. You might use a pantograph, which is a mechanical linkage connecting rods based on parallelo- grams. Figure2 shows a draftsman’s pantograph 3 reproducing a map outline at 2.5 times the size of the original. As we may observe from the above examples, a combination of two or more points and rods creates a mechanism to transmit motion. In general, a linkage is a system of interconnected rods for transmitting or regulating the motion of a mechanism. Link- ages are present in every corner of life, such as the windshield wiper linkage of a car4, the pop-up plug of a bathroom sink5, operating mechanism for elevator doors6, and many mechanical devices. See Figure3 for illustrations. 1Hyung Ju Nam is a junior at Washburn Rural High School in Kansas, USA. 2Kim Christian Jalosjos is a sophomore at Washburn Rural High School in Kansas, USA. -
Some Curves and the Lengths of Their Arcs Amelia Carolina Sparavigna
Some Curves and the Lengths of their Arcs Amelia Carolina Sparavigna To cite this version: Amelia Carolina Sparavigna. Some Curves and the Lengths of their Arcs. 2021. hal-03236909 HAL Id: hal-03236909 https://hal.archives-ouvertes.fr/hal-03236909 Preprint submitted on 26 May 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Some Curves and the Lengths of their Arcs Amelia Carolina Sparavigna Department of Applied Science and Technology Politecnico di Torino Here we consider some problems from the Finkel's solution book, concerning the length of curves. The curves are Cissoid of Diocles, Conchoid of Nicomedes, Lemniscate of Bernoulli, Versiera of Agnesi, Limaçon, Quadratrix, Spiral of Archimedes, Reciprocal or Hyperbolic spiral, the Lituus, Logarithmic spiral, Curve of Pursuit, a curve on the cone and the Loxodrome. The Versiera will be discussed in detail and the link of its name to the Versine function. Torino, 2 May 2021, DOI: 10.5281/zenodo.4732881 Here we consider some of the problems propose in the Finkel's solution book, having the full title: A mathematical solution book containing systematic solutions of many of the most difficult problems, Taken from the Leading Authors on Arithmetic and Algebra, Many Problems and Solutions from Geometry, Trigonometry and Calculus, Many Problems and Solutions from the Leading Mathematical Journals of the United States, and Many Original Problems and Solutions. -
Tropical Curves
Tropical Curves Nathan Pflueger 24 February 2011 Abstract A tropical curve is a graph with specified edge lengths, some of which may be infinite. Various facts and attributes about algebraic curves have analogs for tropical curves. In this article, we focus on divisors and linear series, and prove the Riemann-Roch formula for divisors on tropical curves. We describe two ways in which algebraic curves may be transformed into tropical curves: by aboemas and by specialization on arithmetic surfaces. We discuss how the study of linear series on tropical curves can be used to obtain results about linear series on algebraic curves, and summarize several recent applications. Contents 1 Introduction 2 2 From curves to graphs 3 2.1 Amoebas of plane curves . .3 2.2 Curves over the field of Puiseux series . .4 2.3 Specialization . .5 3 Metric graphs and tropical curves 6 4 Divisors and linear equivalence on tropical curves 9 4.1 The Riemann-Roch criterion . 12 4.2 Tropical Riemann-Roch . 14 5 Tropical plane curves 17 5.1 Tropical algebra and tropical projective space . 17 5.2 Tropical curves in R2 ................................... 18 5.3 Calculation of the genus . 23 5.4 Stable intersection and the tropical B´ezouttheorem . 24 5.5 Classical B´ezoutfrom tropical B´ezout . 29 5.6 Enumerative geometry of tropical plane curves . 31 6 Tropical curves via specialization 32 6.1 The specialization map and specialization lemma . 32 6.2 The canonical divisor of a graph is canonical . 34 6.3 A tropical proof of the Brill-Noether theorem . 34 1 1 Introduction The origins of tropical geometry lie in the study of tropical algebra, whose basic object is the set R [ {−∞} equipped with the operations x ⊕ y = max(x; y) and x ⊗ y = x + y. -
Apollonius Representation and Complex Geometry of Entangled Qubit States
APOLLONIUS REPRESENTATION AND COMPLEX GEOMETRY OF ENTANGLED QUBIT STATES A Thesis Submitted to the Graduate School of Engineering and Sciences of Izmir˙ Institute of Technology in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in Mathematics by Tugçe˜ PARLAKGÖRÜR July 2018 Izmir˙ We approve the thesis of Tugçe˜ PARLAKGÖRÜR Examining Committee Members: Prof. Dr. Oktay PASHAEV Department of Mathematics, Izmir˙ Institute of Technology Prof. Dr. Zafer GEDIK˙ Faculty of Engineering and Natural Sciences, Sabancı University Asst. Prof. Dr. Fatih ERMAN Department of Mathematics, Izmir˙ Institute of Technology 02 July 2018 Prof. Dr. Oktay PASHAEV Supervisor, Department of Mathematics Izmir˙ Institute of Technology Prof. Dr. Engin BÜYÜKA¸SIK Prof. Dr. Aysun SOFUOGLU˜ Head of the Department of Dean of the Graduate School of Mathematics Engineering and Sciences ACKNOWLEDGMENTS It is a great pleasure to acknowledge my deepest thanks and gratitude to my su- pervisor Prof. Dr. Oktay PASHAEV for his unwavering support, help, recommendations and guidance throughout this master thesis. I started this journey many years ago and he was supported me with his immense knowledge as a being teacher, friend, colleague and father. Under his supervisory, I discovered scientific world which is limitless, even the small thing creates the big problem to solve and it causes a discovery. Every discov- ery contains difficulties, but thanks to him i always tried to find good side of science. In particular, i would like to thank him for constructing a different life for me. I sincerely thank to Prof. Dr. Zafer GEDIK˙ and Asst. Prof. Dr. Fatih ERMAN for being a member of my thesis defence committee, their comments and supports. -
Dissertation Hyperovals, Laguerre Planes And
DISSERTATION HYPEROVALS, LAGUERRE PLANES AND HEMISYSTEMS { AN APPROACH VIA SYMMETRY Submitted by Luke Bayens Department of Mathematics In partial fulfillment of the requirements For the Degree of Doctor of Philosophy Colorado State University Fort Collins, Colorado Spring 2013 Doctoral Committee: Advisor: Tim Penttila Jeff Achter Willem Bohm Chris Peterson ABSTRACT HYPEROVALS, LAGUERRE PLANES AND HEMISYSTEMS { AN APPROACH VIA SYMMETRY In 1872, Felix Klein proposed the idea that geometry was best thought of as the study of invariants of a group of transformations. This had a profound effect on the study of geometry, eventually elevating symmetry to a central role. This thesis embodies the spirit of Klein's Erlangen program in the modern context of finite geometries { we employ knowledge about finite classical groups to solve long-standing problems in the area. We first look at hyperovals in finite Desarguesian projective planes. In the last 25 years a number of infinite families have been constructed. The area has seen a lot of activity, motivated by links with flocks, generalized quadrangles, and Laguerre planes, amongst others. An important element in the study of hyperovals and their related objects has been the determination of their groups { indeed often the only way of distinguishing them has been via such a calculation. We compute the automorphism group of the family of ovals constructed by Cherowitzo in 1998, and also obtain general results about groups acting on hyperovals, including a classification of hyperovals with large automorphism groups. We then turn our attention to finite Laguerre planes. We characterize the Miquelian Laguerre planes as those admitting a group containing a non-trivial elation and acting tran- sitively on flags, with an additional hypothesis { a quasiprimitive action on circles for planes of odd order, and insolubility of the group for planes of even order. -
Isoptics of a Closed Strictly Convex Curve. - II Rendiconti Del Seminario Matematico Della Università Di Padova, Tome 96 (1996), P
RENDICONTI del SEMINARIO MATEMATICO della UNIVERSITÀ DI PADOVA W. CIESLAK´ A. MIERNOWSKI W. MOZGAWA Isoptics of a closed strictly convex curve. - II Rendiconti del Seminario Matematico della Università di Padova, tome 96 (1996), p. 37-49 <http://www.numdam.org/item?id=RSMUP_1996__96__37_0> © Rendiconti del Seminario Matematico della Università di Padova, 1996, tous droits réservés. L’accès aux archives de la revue « Rendiconti del Seminario Matematico della Università di Padova » (http://rendiconti.math.unipd.it/) implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/conditions). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit conte- nir la présente mention de copyright. Article numérisé dans le cadre du programme Numérisation de documents anciens mathématiques http://www.numdam.org/ Isoptics of a Closed Strictly Convex Curve. - II. W. CIE015BLAK (*) - A. MIERNOWSKI (**) - W. MOZGAWA(**) 1. - Introduction. ’ This article is concerned with some geometric properties of isoptics which complete and deepen the results obtained in our earlier paper [3]. We therefore begin by recalling the basic notions and necessary results concerning isoptics. An a-isoptic Ca of a plane, closed, convex curve C consists of those points in the plane from which the curve is seen under the fixed angle .7r - a. We shall denote by C the set of all plane, closed, strictly convex curves. Choose an element C and a coordinate system with the ori- gin 0 in the interior of C. Let p(t), t E [ 0, 2~c], denote the support func- tion of the curve C. -
Some Well Known Curves Some Well Known Curves
Dr. Sk Amanathulla Asst. Prof., Raghunathpur College Some Well Known Curves Some well known curves Circle: Cartesian equation: x2 y 2 a 2 Polar equation: ra Parametric equation: x acos t , y a sin t ,0 t 2 Pedal equation: pr Parabola: Cartesian equation: y2 4 ax Polar equation: l 1 cos (focus as pole) r Parametric equation: x at2 , y 2 at , t Pedal equation: p2 ar (focus as pole) Intrinsic equation: s alog cot cos ec a cot cos ec Parabola: Cartesian equation: x2 4 ay Polar equation: l 1 sin (focus as pole) r Parametric equation: x2 at , y at2 , t Pedal equation: (focus as pole) Intrinsic equation: s alog sce tan a tan sec Page 1 of 7 Dr. Sk Amanathulla Asst. Prof., Raghunathpur College Some Well Known Curves Ellipse: xy22 Cartesian equation: 1 ab22 Polar equation: l 1e cos (focus as pole) r Parametric equation: x acos t , y b sin t ,0 t 2 ba2 2 Pedal equation: 1 pr2 Hyperbola: xy22 Cartesian equation: 1 ab22 l Polar equation: 1e cos r Parametric equation: x acosh t , y b sinh t , t ba2 2 Pedal equation: 1 pr2 Rectangular hyperbola: Cartesian equation: xy c2 Polar equation: rc22sin 2 2 Parametric equation: c x ct,, y t t Pedal equation: pr 2 c2 Page 2 of 7 Dr. Sk Amanathulla Asst. Prof., Raghunathpur College Some Well Known Curves Cycloid: Parametric equation: x a t sin t , y a 1 cos t 02t Intrinsic equation: sa4 sin Inverted cycloid: Parametric equation: x a t sin t , y a 1 cos t 02t Intrinsic equation: sa 4 sin Asteroid: 2 2 2 Cartesian equation: x3 y 3 a 3 Parametric equation: x acos33 t , y a sin t 0 t 2 Pedal equation: r2 a 23 p 2 Intrinsic equation: 4sa 3 cos 2 0 Page 3 of 7 Dr. -
Chapter 5 Manifolds, Tangent Spaces, Cotangent
Chapter 5 Manifolds, Tangent Spaces, Cotangent Spaces, Submanifolds, Manifolds With Boundary 5.1 Charts and Manifolds In Chapter 1 we defined the notion of a manifold embed- ded in some ambient space, RN . In order to maximize the range of applications of the the- ory of manifolds it is necessary to generalize the concept of a manifold to spaces that are not a priori embedded in some RN . The basic idea is still that, whatever a manifold is, it is atopologicalspacethatcanbecoveredbyacollectionof open subsets, U↵,whereeachU↵ is isomorphic to some “standard model,” e.g.,someopensubsetofEuclidean space, Rn. 293 294 CHAPTER 5. MANIFOLDS, TANGENT SPACES, COTANGENT SPACES Of course, manifolds would be very dull without functions defined on them and between them. This is a general fact learned from experience: Geom- etry arises not just from spaces but from spaces and interesting classes of functions between them. In particular, we still would like to “do calculus” on our manifold and have good notions of curves, tangent vec- tors, di↵erential forms, etc. The small drawback with the more general approach is that the definition of a tangent vector is more abstract. We can still define the notion of a curve on a manifold, but such a curve does not live in any given Rn,soitit not possible to define tangent vectors in a simple-minded way using derivatives. 5.1. CHARTS AND MANIFOLDS 295 Instead, we have to resort to the notion of chart. This is not such a strange idea. For example, a geography atlas gives a set of maps of various portions of the earth and this provides a very good description of what the earth is, without actually imagining the earth embedded in 3-space.