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An oval (from Latin ovum 'egg') is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas of mathematics (projective geometry, technical drawing, etc.), it is given a more precise definition, which may include either one or two axes of symmetry of an ellipse. In common English, the term is used in a broader sense: any shape which reminds one of an egg. The three-dimensional version of an oval is called an ovoid.
Oval in geometry
[edit]
The term oval when used to describe curves in geometry is not well defined, except in the context of projective geometry. Many distinct curves are commonly called ovals or are said to have an "oval shape". Generally, to be called an oval, a plane curve should resemble the outline of an egg or an ellipse. In particular, these are common traits of ovals:
- they are differentiable (smooth-looking),[1] simple (not self-intersecting), convex, closed, plane curves;
- their shape does not depart much from that of an ellipse, and
- an oval would generally have an axis of symmetry, but this is not required.
Here are examples of ovals described elsewhere:
- Cassini ovals
- portions of some elliptic curves
- Moss's egg
- superellipse
- Cartesian oval
- stadium
An ovoid is the surface in 3-dimensional space generated by rotating an oval curve about one of its axes of symmetry. The adjectives ovoidal and ovate mean having the characteristic of being an ovoid, and are often used as synonyms for "egg-shaped".
Projective geometry
[edit]
- In a projective plane a set Ω of points is called an oval, if:
- Any line l meets Ω in at most two points, and
- For any point P ∈ Ω there exists exactly one tangent line t through P, i.e., t ∩ Ω = {P}.
For finite planes (i.e. the set of points is finite) there is a more convenient characterization:[2]
- For a finite projective plane of order n (i.e. any line contains n + 1 points) a set Ω of points is an oval if and only if |Ω| = n + 1 and no three points are collinear (on a common line).
An ovoid in a projective space is a set Ω of points such that:
- Any line intersects Ω in at most 2 points,
- The tangents at a point cover a hyperplane (and nothing more), and
- Ω contains no lines.
In the finite case only for dimension 3 there exist ovoids. A convenient characterization is:
- In a 3-dim. finite projective space of order n > 2 any pointset Ω is an ovoid if and only if |Ω| and no three points are collinear.[3]
Egg shape
[edit]The shape of an egg is approximated by the "long" half of a prolate spheroid, joined to a "short" half of a roughly spherical ellipsoid, or even a slightly oblate spheroid. These are joined at the equator and share a principal axis of rotational symmetry, as illustrated above. Although the term egg-shaped usually implies a lack of reflection symmetry across the equatorial plane, it may also refer to true prolate ellipsoids. It can also be used to describe the 2-dimensional figure that, if revolved around its major axis, produces the 3-dimensional surface.
Technical drawing
[edit]
In technical drawing, an oval is a figure that is constructed from two pairs of arcs, with two different radii (see image on the right). The arcs are joined at a point in which lines tangential to both joining arcs lie on the same line, thus making the joint smooth. Any point of an oval belongs to an arc with a constant radius (shorter or longer), but in an ellipse, the radius is continuously changing.
In common speech
[edit]In common speech, "oval" means a shape rather like an egg or an ellipse, which may be two-dimensional or three-dimensional. It also often refers to a figure that resembles two semicircles joined by a rectangle, like a cricket infield, speed skating rink or an athletics track. However, this is most correctly called a stadium.
The term "ellipse" is often used interchangeably with oval, but it has a more specific mathematical meaning.[4] The term "oblong" is also used to mean oval,[5] though in geometry an oblong refers to rectangle with unequal adjacent sides, not a curved figure.[6]
See also
[edit]- Ellipse
- Ellipsoidal dome
- Stadium (geometry)
- Vesica piscis – a pointed oval
- Symbolism of domes
Notes
[edit]- ^ If the property makes sense: on a differentiable manifold. In more general settings one might require only a unique tangent line at each point of the curve.
- ^ Dembowski 1968, p. 147
- ^ Dembowski 1968, p. 48
- ^ "Definition of ellipse in US English by Oxford Dictionaries". New Oxford American Dictionary. Oxford University Press. Archived from the original on September 27, 2016. Retrieved 9 July 2018.
- ^ "Definition of oblong in US English by Oxford Dictionaries". New Oxford American Dictionary. Oxford University Press. Archived from the original on September 24, 2016. Retrieved 9 July 2018.
- ^ "Definition of quadliraterals, Clark University, Dept. of Maths and Computer Science". Clark University, Definitions of quadrilaterals. Retrieved 21 October 2020.
- Dembowski, Peter (1968), Finite geometries, Ergebnisse der Mathematik und ihrer Grenzgebiete, Band 44, Berlin, New York: Springer-Verlag, ISBN 3-540-61786-8, MR 0233275
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from Grokipedia
An oval is a closed curve in a plane that resembles the outline of an egg, characterized by its smooth, elongated, and rounded form. Unlike a circle, it is flattened along one axis, often appearing egg-like or elliptical in shape.[1][2] The term "oval" originates from the Latin word ovum, meaning "egg," reflecting its resemblance to the natural contour of an egg.[3]
In mathematics, an oval is typically described as a simple, convex, closed curve, but it lacks a precise definition comparable to that of an ellipse, which is rigorously defined by the set of points where the sum of distances to two fixed foci remains constant.[1] Ovals may possess one or two axes of reflection symmetry, though they are not required to have bilateral symmetry like true ellipses.[4] This flexibility allows ovals to encompass a broader range of egg-shaped or stadium-like figures, including rounded rectangles in practical applications.[5]
Ovals appear extensively in geometry, art, architecture, and engineering due to their aesthetic and functional properties, such as providing smooth transitions and enclosing areas efficiently.[2] For instance, oval shapes are common in racetracks, where they facilitate continuous motion, and in design elements like mirrors or tabletops for their elegant curvature.[5] In three dimensions, the analogous form is an ovoid, extending the concept to solid objects like eggs or rugby balls.[1]
Definition and Properties
General Definition
An oval is a closed, plane curve that is smooth, convex, and without self-intersections, characterized by having pairs of parallel tangent lines at its points of maximum and minimum width. This geometric figure encloses a bounded region and resembles a rounded, elongated shape, often evoking the outline of an egg. Unlike more rigidly defined curves, the term "oval" applies broadly to such forms that maintain convexity, meaning any line segment connecting two points on the curve lies entirely within the enclosed area.[6] The word "oval" originates from the Latin ovum, meaning "egg," reflecting its association with egg-like contours. It entered English usage around the 1570s, initially describing shapes that are egg-shaped or elliptical in form.[7] This etymology underscores the intuitive, organic inspiration behind the term, distinguishing it from purely abstract mathematical constructs. In contrast to a circle, which is perfectly round with all points equidistant from the center, or an ellipse, a specific conic section defined by a constant sum of distances to two foci, an oval serves as a more general descriptor for any smooth, convex, egg-shaped curve.[1] Ellipses form a subset of ovals, sharing similar symmetry but adhering to precise conic properties. Visually, an oval typically exhibits symmetry about a major axis (longest diameter) and a minor axis (shortest diameter), though it need not conform to the exact proportional relationships of an ellipse and may feature only one axis of reflection symmetry in some cases.[4]Key Properties
Many ovals, particularly those with bilateral symmetry such as elliptical ovals, possess reflection symmetry across both their major and minor axes, meaning that the curve is mirror-symmetric with respect to these perpendicular lines passing through the center. In the case of elliptical ovals, this bilateral symmetry is complemented by 180-degree rotational symmetry around the center.[8] For symmetric ovals, the curvature varies continuously along its length, with the highest values typically occurring at the ends of the minor axis—where the curve bends most sharply—and the lowest at the ends of the major axis, reflecting the elongated nature of the shape. As convex, simple closed plane curves, ovals enclose a bounded interior region whose area can be computed using standard integration techniques, while their perimeter represents the total length of the boundary. By the Jordan curve theorem, every such oval divides the plane into exactly two connected components: a bounded interior and an unbounded exterior.[9] For ovals with two axes of symmetry, at the extremities—the endpoints of the major and minor axes—the tangent lines to the oval are parallel to each other, perpendicular to the respective axis. The corresponding normal lines, being perpendicular to these tangents by definition, align with the axes of symmetry at these points. For precise area calculations in elliptical cases, reference may be made to elliptic integrals, as detailed in the section on elliptical ovals.Geometric Forms
Elliptical Ovals
An ellipse is a conic section defined as the set of all points in a plane such that the sum of the distances from any point on the curve to two fixed points, called the foci, is constant and equal to , where is the semi-major axis length.[10][11] This constant sum distinguishes the ellipse as a closed, bounded curve among conic sections, serving as the primary mathematical model for elliptical ovals that are elongated and symmetric.[12] The formalization of the ellipse as a non-circular oval traces back to the Greek mathematician Apollonius of Perga, who in the 3rd century BCE systematically described conic sections in his eight-volume work Conics, introducing the term "ellipse" derived from the Greek for "deficiency" to reflect its geometric shortfall relative to a circle.[13][14] In standard position, centered at the origin with the major axis along the x-axis, the equation of an ellipse is given by where , denotes the semi-major axis, and the semi-minor axis, producing an elongated oval shape when significantly exceeds .[15][16] Key parameters characterizing an ellipse include the semi-major axis , semi-minor axis , eccentricity (which measures deviation from circularity, ranging from 0 for a circle to approaching 1 for highly elongated ovals), linear eccentricity (the distance from the center to each focus), and the directrix (a line at distance from the center, associated with the focus-directrix definition of conics).[17][11] Ellipses exhibit notable properties, including the reflection principle: a ray originating from one focus reflects off the ellipse's boundary at equal angles to the tangent, directing it precisely to the other focus, a consequence of the constant sum of distances.[18][19] The area enclosed by an ellipse is , scaling linearly with both axes.[20][21] For the perimeter, no elementary closed-form expression exists, but Ramanujan's second approximation provides high accuracy: where , offering relative errors typically below for most eccentricities.[22][23]Non-Elliptical Ovals
Non-elliptical ovals refer to closed curves that approximate the rounded, elongated form of ellipses but deviate from the precise conic section definition, often incorporating straight segments or higher-order parameters to achieve specific shapes for practical or aesthetic purposes.[24] These shapes maintain overall convexity and smoothness, similar to ellipses, but lack the defining property of a constant sum of distances to two foci, resulting in variable curvature and no fixed eccentricity under conic rules.[24] They are frequently employed in design and engineering where exact elliptical geometry is unnecessary or difficult to construct manually.[25] A prominent example is the stadium oval, also known as a capsule or racetrack shape, formed by two semicircles of equal radius connected by two parallel straight lines tangent to the semicircles.[26] This configuration yields a simple, symmetric oval with total length and width , where the straight segments span .[26] The stadium's hybrid nature—combining circular arcs and linear elements—facilitates easy construction using basic tools like compasses and straightedges, making it ideal for applications such as track layouts or boundary definitions in billiard dynamics.[27] Another key example is the superellipse, a generalization of the ellipse introduced by Gabriel Lamé in 1818, defined by the equation for , where and are semi-axes lengths.[28] For , the curve exhibits straighter sides and sharper corners compared to an ellipse (), creating a more rectangular or "pinched" appearance while remaining convex and smooth.[28] Superellipses are valued for their parametric flexibility, allowing shapes between ellipses and rectangles, and have been applied in industrial design, such as furniture and logos, due to their aesthetic balance.[29] Construction methods for non-elliptical ovals often prioritize practicality over conic precision. One approach involves multiple foci, where the curve is the locus of points with a constant summed distance to fixed points, termed an n-ellipse or polyellipse; this produces elongated, egg-like ovals with varying local eccentricity not bound by two-focus rules.[24] Parametric representations, such as those from hypocycloids—generated by a point on a small circle rolling inside a larger fixed circle—can yield oval-like curves for certain radius ratios, offering smooth, closed paths through trigonometric equations like , .[24] These methods enable approximations that are simpler to draw or compute than true ellipses, especially in artistic or mechanical contexts where asymmetry or straight segments enhance usability.[24] Unlike ellipses, which adhere to the constant sum property and uniform conic behavior, non-elliptical ovals exhibit heterogeneous curvature—flatter in some regions and more rounded in others—yet preserve closure and boundedness for practical simulations and constructions.[26] This variability makes them suitable for approximations in fields requiring deviated forms, such as racetrack design or parametric modeling, without the need for complex focal adjustments.[24]Advanced Mathematical Contexts
Projective Geometry
In projective geometry, ovals are understood as bounded conic sections that arise under projective transformations, which preserve incidence relations such as points lying on lines and lines intersecting at points, but not Euclidean distances or angles.[30] These transformations map any non-degenerate conic, including ellipses (which serve as the prototypical ovals), to another conic while maintaining their projective properties.[30] Specifically, an ellipse can be projected onto a hyperbola or parabola, depending on how the line at infinity interacts with the curve, though under the subclass of affine projections—which preserve parallelism and boundedness—the resulting figure remains a visually similar bounded oval.[31] A significant application in this context is Poncelet's porism, which describes closed polygonal chains inscribed in one conic and circumscribed about another, applicable to pairs of oval conics where such polygons exist infinitely many times starting from any point on the outer conic.[32] This theorem highlights the interrelations between conics under projective mappings, demonstrating how polygons tangent to an inner oval conic and vertex-bound to an outer one close after a fixed number of sides.[32] Dual conics further extend this framework, distinguishing point conics (loci of points satisfying a quadratic equation) from line conics (envelopes of tangent lines), both of which can produce oval envelopes when the dual structure yields bounded regions in the projective plane.[31] The dual of a point conic is its envelope of tangents, and for oval-like conics, this duality preserves the envelope's bounded, closed nature under projective equivalence.[30] Historically, the foundations for treating ovals within projective geometry were laid in the 17th century through extensions of Desargues' theorem (published 1648), which relates perspective triangles and their intersections, and Pascal's theorem (1640), which concerns hexagons inscribed in conics, both generalized to conic sections including ovals.[33] These theorems, pivotal in establishing projective invariance for conics, influenced modern applications such as shape recognition in computer vision, where projective transformations of oval conics enable robust detection of curved objects across varying viewpoints.[34]Other Oval Curves
The Cassini oval is a specialized quartic curve defined as the set of points in the plane where the product of the distances to two fixed foci, separated by distance , remains constant at .[35] Its Cartesian equation is given by For , the curve forms a single convex oval shape; as decreases toward , it pinches inward, resembling a peanut; and at , it bifurcates into a figure-eight lemniscate of Bernoulli.[35] These properties highlight the curve's algebraic degree of four and its sensitivity to parameter ratios, distinguishing it from conic sections.[35]Natural and Biological Ovals
Egg Shapes
An ovoid is an egg-shaped curve or solid that deviates from perfect symmetry, typically featuring asymmetry along its long axis with one more pointed end, known as the animal pole, and the opposite more rounded end, referred to as the vegetal pole. This polarity arises during oogenesis, where the animal pole corresponds to the region of active cell division and embryonic development, while the vegetal pole contains nutrient-rich yolk. In avian eggs, this asymmetry distinguishes ovoids from symmetric ellipses, enabling functional adaptations in reproduction and incubation.[36][37] Mathematical models of ovoids capture this asymmetry through combinations of basic geometric forms. Hügelschäffer's oval, developed in the mid-20th century, constructs the shape as the Newton transform of two circles, effectively blending an ellipse with a modified circular arc to replicate the pointed and blunt poles of bird eggs. This model excels for classical ovoid profiles, allowing precise parameterization by length , breadth , and a shift parameter for asymmetry. Alternatively, parametric equations such as introduce the necessary deviation from elliptical symmetry via the higher-order term, where and scale the axes and controls pointedness; these forms align well with empirical egg contours in biological studies.[38] Avian eggs exemplify ovoids, with the domestic chicken (Gallus gallus domesticus) producing eggs averaging 58 mm (5.8 cm) in length and 40 mm (4.0 cm) in maximum breadth. Their volume can be estimated using the formula , where with and in cm yielding cm³, resulting in approximately 47 cm³ for these dimensions—a value close to the typical 50–60 cm³ range for standard eggs, accounting for the ovoid's non-ellipsoidal form without overestimation.[40] Evolutionary pressures favor this asymmetry in birds: streamlined flight selects for more elliptical and asymmetric eggs to ease oviduct passage and reduce maternal weight, while the pointed end promotes rolling toward the nest center during incubation, enhancing survival. In contrast, some reptile species, such as certain turtles, lay more spherical eggs that minimize surface area for volume in buried clutches, highlighting ovoid specialization in oviparous birds.[41][42][43]Other Natural Occurrences
In plants, streamlined leaves, often elliptical or lanceolate, are prevalent in species such as willows (Salix spp.), where their shape minimizes wind resistance and enhances aerodynamic stability, reducing the risk of branch breakage during storms.[44][45] This form is often favored by natural selection in windy or exposed environments, as elongated or elliptical outlines allow better alignment with airflow compared to broader shapes. Similarly, seed pods exhibit oval configurations, as seen in acorns of oaks like the white oak (Quercus alba), whose ovoid nuts facilitate dispersal by rolling or animal transport while protecting the embryo.[46] Geologically, oval pebbles form through prolonged river erosion, where constant tumbling and collision with other stones and the riverbed abrade angular edges into smoother, convex shapes that offer minimal hydrodynamic resistance for downstream transport.[47][48] This physical abrasion process preferentially erodes protrusions, yielding oblate or ellipsoidal forms that are more stable in flowing water.[49] In cellular biology, many prokaryotic cells adopt oval shapes, such as coccobacilli (short, oval rods) in species like Haemophilus influenzae, where the dimensions optimize flagellar propulsion and nutrient uptake during motility in viscous environments.[50][51] Eukaryotic nuclei are frequently oval, as in fibroblasts, providing structural efficiency for chromosomal organization and division without excessive volume.[52] Astronomical bodies follow near-elliptical paths, as described by Kepler's first law, where planets orbit the Sun in ellipses with the central body at one focus, a shape arising from gravitational dynamics that balances orbital stability and energy conservation.[53] These oval occurrences in nature stem from processes like physical abrasion in geological settings, which sculpts efficient, low-drag forms, and natural selection in biological systems, favoring convex outlines that enhance survival through improved locomotion, dispersal, or environmental resilience.[47][45]Practical Applications
Technical Drawing
In technical drawing, ellipse templates are widely used tools consisting of pre-cut openings in plastic or acrylic sheets that allow draftsmen to trace elliptical shapes of various sizes and eccentricities with precision. These templates facilitate accurate representation of ovals in blueprints and schematics, particularly for components like pipe fittings or lens profiles.[54] Another manual method employs the trammel, a mechanism with two sliders mounted on perpendicular rods that trace elliptical points by maintaining constant sums of distances from two foci, enabling the construction of ovals without complex calculations. This technique, attributed to Archimedes, is effective for larger-scale drawings in drafting.[55] For approximating ovoid shapes, which deviate slightly from true ellipses, the concentric circle method involves drawing two overlapping circles with diameters matching the major and minor axes, then projecting radial lines to form the curve, providing a quick manual approximation suitable for preliminary designs.[56] Construction techniques include the four-center method, where an oval is approximated by drawing four circular arcs centered at points offset along the major and minor axes, offering a simple geometric solution for non-ideal ellipses in engineering sketches. In modern computer-aided design (CAD) software, algorithms utilizing Bézier curves simulate ovals by defining control points that generate smooth, parametric approximations of elliptical paths, allowing scalable and editable representations.[57][58] The International Organization for Standardization (ISO) 128 series establishes principles for representing lines and views in technical drawings, including guidelines for depicting curved forms like ovals to ensure clarity and uniformity in engineering documentation. Historically, 19th-century advancements in drafting tools included specialized oval protractors and templates that combined angular measurements with elliptical cutouts to aid architects and engineers in precise curve rendering.Sports and Engineering
In sports, ovals are prominently featured in track and field venues, where the standard 400-meter running track follows World Athletics specifications, consisting of two parallel straights each measuring 84.39 meters and two semicircular turns with a radius of 36.5 meters, enabling consistent lane distances and fair competition.[59] This configuration provides balanced flow for athletes, minimizing abrupt directional changes and promoting even pacing across distances like the 400-meter race. Horse racing tracks in the United States commonly adopt a one-mile dirt oval layout, with as of 2021 approximately 68% of North American dirt ovals measuring about one mile in circumference to standardize race distances and accommodate thoroughbred speeds up to 40 miles per hour.[60] Oval shapes also appear in motorsports, particularly in NASCAR, where tri-oval tracks such as Daytona International Speedway span 2.5 miles, featuring 31-degree banking in the turns, 18-degree banking in the tri-oval entrance, and 3-degree banking on the backstretch to enhance high-speed stability and overtaking opportunities for stock cars reaching over 200 miles per hour.[61] While FIFA mandates rectangular pitches for international soccer matches, measuring 100-110 meters in length and 64-75 meters in width, some multi-purpose stadiums with oval designs, such as those in Australia, adapt by marking rectangular fields within the oval turf to host adapted soccer events. The oval's advantages in sports venues include optimized circulation for continuous motion and reduced centrifugal forces compared to circular or irregular shapes, contributing to athlete and vehicle safety. In engineering, oval gears, also known as elliptical gears, enable variable speed transmission by altering the gear ratio during rotation, which is useful in applications requiring non-constant output speeds, such as certain pumps and machinery drives.[62] For pressure vessels, including boilers, ASME Boiler and Pressure Vessel Code Section VIII Division 1 specifies elliptical (ellipsoidal) heads, typically with a 2:1 semi-major to semi-minor axis ratio, to cap cylindrical shells efficiently under internal pressures up to several hundred psi, as these shapes distribute hoop and longitudinal stresses more evenly than flat or hemispherical alternatives.[63] Oval configurations in engineering components like pipes and vessels offer advantages in stress distribution by providing greater resistance to buckling and deformation under load while maintaining material efficiency, particularly in scenarios where space constraints favor elongated profiles over circular ones.[63]Cultural and Linguistic Usage
In Common Speech
In everyday language, the term "oval" often describes facial features considered aesthetically balanced and versatile, particularly in physiognomy where an oval face shape is associated with traits like diplomacy, leadership, and broad-mindedness.[64] This shape, slightly longer than wide with a narrower jawline relative to the cheekbones, is frequently praised in popular descriptions as an "ideal" form that suits various hairstyles and makeup styles.[65] In pharmaceuticals, oval tablets are commonly designed for ease of swallowing, as their elongated form reduces esophageal transit time compared to round pills of similar volume, making them preferable for patients with mild dysphagia.[66] Studies confirm that such shapes, especially when film-coated, improve swallowability by minimizing the risk of lodging in the throat.[67] Similarly, oval tables in conference or dining settings are chosen to facilitate smoother discussion flow, as their rounded ends promote inclusivity without a dominant "head" position, encouraging equal participation in conversations.[68] Idiomatic uses of "oval" extend to prominent cultural references, such as the Oval Office, the official workspace of the U.S. President in the White House, which derives its name from the room's elongated, oval-like shape established in 1909 during President William Howard Taft's expansion of the West Wing.[69] In motorsports slang, "go oval" refers to transitioning from road or street racing to oval track competitions, a phrase popularized in contexts like NASCAR where drivers adapt to the high-speed, circular demands of banked circuits.[70] Casual speech sometimes misapplies "oval" to astronomical phenomena, such as describing elliptical galaxies—which are technically ellipsoidal with smooth, featureless distributions of older stars—as "oval galaxies," an approximation that blurs the precise mathematical distinction between ovals and ellipses. This loose usage arises from visual similarities in their rounded-to-elongated profiles observed through telescopes.[72] In British English, "oval" regionally denotes cricket venues, most notably The Oval in London, a historic ground established in 1845 on former market garden land in Kennington, serving as the headquarters of Surrey County Cricket Club and host to international Test matches since 1880.[73] The site's name reflects its original oblong layout, which has become synonymous with elite cricket in colloquial parlance.[74] In Australian English, "oval" commonly refers to sports playing fields, particularly for Australian rules football (AFL) and cricket, which are characteristically oval in shape. AFL grounds are standardized as ovals measuring between 135–185 metres in length and 110–155 metres in width.[75] Cricket fields are also oval, as described in official accounts of the sport.[76] Examples include the Melbourne Cricket Ground, a prominent venue that exemplifies this usage in Australian sports culture.Symbolism and Representation
In religious iconography, the mandorla—an almond-shaped oval—serves as a powerful symbol enclosing sacred figures, representing the aura of divine light and the union of earthly and heavenly realms. This form, derived from the vesica piscis intersection of two circles, underscores themes of sacral glory and transcendence in Christian art, appearing prominently in depictions of Christ during the Transfiguration or Ascension.[77][78][79] During the Renaissance, oval elements enhanced artistic compositions, as seen in Titian's Vanity (c. 1515–1520), where a woman holds an ornate oval mirror reflecting jewels and an old woman, symbolizing introspection and the fleeting nature of beauty. Oval frames and mirrors in such portraits emphasized harmony and proportion, aligning with the period's revival of classical ideals.[80] Ovals broadly symbolize wholeness, eternity, and fertility across cultures, often evoking the egg's form as a vessel of life and renewal. In Celtic art, interlaced oval motifs within knots represent interconnected cycles of existence and creative energy. This fertility association extends to modern design, exemplified by the Oval Office in the White House, whose shape—modeled after 18th-century English saloons—conveys presidential authority, unity, and democratic power.[81][82][83] In photography, oval vignettes emerged in the mid-19th century with cartes de visite, where masked oval borders focused attention on subjects, creating an intimate, portrait-like effect amid the era's mass-produced images. Contemporary media leverages ovals in CGI for fluid, organic animations; their curved contours facilitate seamless motion without angular discontinuities, as in rendering planetary orbits or character paths in films.[84]References
- https://www.[researchgate](/page/ResearchGate).net/publication/259604597_The_mathematics_of_egg_shape
- https://science.[nasa](/page/NASA).gov/universe/galaxies/types/