Knowledge

Sphere

Source 📝

5677: 5676: 5724: 1661: 49: 4584: 4687: 4888: 268: 4576: 4205: 2817: 4629: 3888: 4614:) consists of circles and/or points if not empty. For example, the diagram to the right shows the intersection of a sphere and a cylinder, which consists of two circles. If the cylinder radius were that of the sphere, the intersection would be a single circle. If the cylinder radius were larger than that of the sphere, the intersection would be empty. 2536: 1602: 1792:
of that sphere (having the height and diameter equal to the diameter of the sphere). This may be proved by inscribing a cone upside down into semi-sphere, noting that the area of a cross section of the cone plus the area of a cross section of the sphere is the same as the area of the cross section of
4142:
in space. Hence, bending a surface will not alter the Gaussian curvature, and other surfaces with constant positive Gaussian curvature can be obtained by cutting a small slit in the sphere and bending it. All these other surfaces would have boundaries, and the sphere is the only surface that lacks a
3891:
A normal vector to a sphere, a normal plane and its normal section. The curvature of the curve of intersection is the sectional curvature. For the sphere each normal section through a given point will be a circle of the same radius: the radius of the sphere. This means that every point on the sphere
6421:
More significantly, Vitruvius (On Architecture, Vitr. 9.8) associated conical sundials with Dionysodorus (early 2nd century bce), and Dionysodorus, according to Eutocius of Ascalon (c. 480–540 ce), used conic sections to complete a solution for Archimedes' problem of cutting a sphere by a plane so
5631:
defines the sphere in book XI, discusses various properties of the sphere in book XII, and shows how to inscribe the five regular polyhedra within a sphere in book XIII. Euclid does not include the area and volume of a sphere, only a theorem that the volume of a sphere varies as the third power of
4602:
Circles on the sphere are, like circles in the plane, made up of all points a certain distance from a fixed point on the sphere. The intersection of a sphere and a plane is a circle, a point, or empty. Great circles are the intersection of the sphere with a plane passing through the center of a
3878:
determined by the original two spheres. In this definition a sphere is allowed to be a plane (infinite radius, center at infinity) and if both the original spheres are planes then all the spheres of the pencil are planes, otherwise there is only one plane (the radical plane) in the pencil.
3565:
The sphere has the smallest surface area of all surfaces that enclose a given volume, and it encloses the largest volume among all closed surfaces with a given surface area. The sphere therefore appears in nature: for example, bubbles and small water drops are roughly spherical because the
2446: 4092:
minimizes its surface area for that volume. A freely floating soap bubble therefore approximates a sphere (though such external forces as gravity will slightly distort the bubble's shape). It can also be seen in planets and stars where gravity minimizes surface area for large celestial
860: 4019:
For a given normal section exists a circle of curvature that equals the sectional curvature, is tangent to the surface, and the center lines of which lie along on the normal line. For example, the two centers corresponding to the maximum and minimum sectional curvatures are called the
3555: 1768: 2812:{\displaystyle V=\int _{0}^{2\pi }\int _{0}^{\pi }\int _{0}^{r}r'^{2}\sin \theta \,dr'\,d\theta \,d\varphi =2\pi \int _{0}^{\pi }\int _{0}^{r}r'^{2}\sin \theta \,dr'\,d\theta =4\pi \int _{0}^{r}r'^{2}\,dr'\ ={\frac {4}{3}}\pi r^{3}.} 1448: 4069:
are curves on a surface that give the shortest distance between two points. They are a generalization of the concept of a straight line in the plane. For the sphere the geodesics are great circles. Many other surfaces share this
3983:
is at right angles to the surface because on the sphere these are the lines radiating out from the center of the sphere. The intersection of a plane that contains the normal with the surface will form a curve that is called a
4157:
Rotating around any axis a unit sphere at the origin will map the sphere onto itself. Any rotation about a line through the origin can be expressed as a combination of rotations around the three-coordinate axis (see
2243: 3716:
of the intersecting spheres. Although the radical plane is a real plane, the circle may be imaginary (the spheres have no real point in common) or consist of a single point (the spheres are tangent at that point).
682: 3642: 649: 2232: 3288: 2525: 1003: 5072: 4348:, this curvature is independent of the sphere's embedding in 3-dimensional space. Also following from Gauss, a sphere cannot be mapped to a plane while maintaining both areas and angles. Therefore, any 4419: 5714: 1928: 1985: 3072: 1453: 3128: 5657:
Archimedes wrote about the problem of dividing a sphere into segments whose volumes are in a given ratio, but did not solve it. A solution by means of the parabola and hyperbola was given by
2967:
can be thought of as the summation of the surface area of an infinite number of spherical shells of infinitesimal thickness concentrically stacked inside one another from radius 0 to radius
5232: 4076:
Of all the solids having a given volume, the sphere is the one with the smallest surface area; of all solids having a given surface area, the sphere is the one having the greatest volume.
3698:. More generally, a sphere is uniquely determined by four conditions such as passing through a point, being tangent to a plane, etc. This property is analogous to the property that three 2058: 4978: 3724:
determined by the tangent planes to the spheres at that point. Two spheres intersect at the same angle at all points of their circle of intersection. They intersect at right angles (are
5147: 1181: 3198: 5723: 3861: 4504: 1436: 4664:
which are aligned directly East–West. For any other bearing, a loxodrome spirals infinitely around each pole. For the Earth modeled as a sphere, or for a general sphere given a
2140: 4777: 4287: – on the sphere, the distance between them is exactly half the length of the circumference. Any other (i.e., not antipodal) pair of distinct points on a sphere 3357: 394:). In geometry unrelated to astronomical bodies, geocentric terminology should be used only for illustration and noted as such, unless there is no chance of misunderstanding. 1309: 281:
is the sphere's radius; any line from the center to a point on the sphere is also called a radius. 'Radius' is used in two senses: as a line segment and also as its length.
3405: 2943: 4138:
is the product of the two principal curvatures. It is an intrinsic property that can be determined by measuring length and angles and is independent of how the surface is
3449: 1258: 1211: 1109: 1032: 4056:* For the sphere the center of every osculating circle is at the center of the sphere and the focal surface forms a single point. This property is unique to the sphere. 5661:. A similar problem – to construct a segment equal in volume to a given segment, and in surface to another segment – was solved later by 4722: 1641: 4746: 1062: 1377: 1285: 4815: 1682: 1597:{\displaystyle {\begin{aligned}x&=x_{0}+r\sin \theta \;\cos \varphi \\y&=y_{0}+r\sin \theta \;\sin \varphi \\z&=z_{0}+r\cos \theta \,\end{aligned}}} 6609: 2971:. At infinitesimal thickness the discrepancy between the inner and outer surface area of any given shell is infinitesimal, and the elemental volume at radius 4009:
For the sphere the curvatures of all normal sections are equal, so every point is an umbilic. The sphere and plane are the only surfaces with this property.
3957:
The width of a surface is the distance between pairs of parallel tangent planes. Numerous other closed convex surfaces have constant width, for example the
348:
is not perfectly spherical, terms borrowed from geography are convenient to apply to the sphere. A particular line passing through its center defines an
4235:; the defining characteristic of a great circle is that the plane containing all its points also passes through the center of the sphere. Measuring by 3917:
The points on the sphere are all the same distance from a fixed point. Also, the ratio of the distance of its points from two fixed points is constant.
2441:{\displaystyle V=\pi \left_{-r}^{r}=\pi \left(r^{3}-{\frac {r^{3}}{3}}\right)-\pi \left(-r^{3}+{\frac {r^{3}}{3}}\right)={\frac {4}{3}}\pi r^{3}.} 4107:
is the average of the two principal curvatures, which is constant because the two principal curvatures are constant at all points of the sphere.
855:{\displaystyle x_{0}={\frac {-b}{a}},\quad y_{0}={\frac {-c}{a}},\quad z_{0}={\frac {-d}{a}},\quad \rho ={\frac {b^{2}+c^{2}+d^{2}-ae}{a^{2}}}.} 3992:. For most points on most surfaces, different sections will have different curvatures; the maximum and minimum values of these are called the 3921:
The first part is the usual definition of the sphere and determines it uniquely. The second part can be easily deduced and follows a similar
3908:
describe eleven properties of the sphere and discuss whether these properties uniquely determine the sphere. Several properties hold for the
6577: 5555:
space, it is not mentioned in the definition and notation. The same applies for the radius if it is taken to equal one, as in the case of a
3583: 4162:). Therefore, a three-parameter family of rotations exists such that each rotation transforms the sphere onto itself; this family is the 6064: 6602: 4174:-axes and rotations around the origin). Circular cylinders are the only surfaces with two-parameter families of rigid motions and the 528: 4031:
For most surfaces the focal surface forms two sheets that are each a surface and meet at umbilical points. Several cases are special:
2151: 442:
has not always been maintained and especially older mathematical references talk about a sphere as a solid. The distinction between "
3213: 6010: 2464: 871: 6387: 4983: 3705:
Consequently, a sphere is uniquely determined by (that is, passes through) a circle and a point not in the plane of that circle.
5258:
is a sphere that has been stretched or compressed in one or more directions. More exactly, it is the image of a sphere under an
294:. Diameters are the longest line segments that can be drawn between two points on the sphere: their length is twice the radius, 4365: 1882: 6595: 6521: 6494: 6459: 6407: 6331: 6157: 5425:-sphere. The ordinary sphere is a 2-sphere, because it is a 2-dimensional surface which is embedded in 3-dimensional space. 1939: 6433: 4250:
hold true for spherical geometry as well, but not all do because the sphere fails to satisfy some of classical geometry's
3027: 4281:
Any pair of points on a sphere that lie on a straight line through the sphere's center (i.e., the diameter) are called
3083: 150: 3728:) if and only if the square of the distance between their centers is equal to the sum of the squares of their radii. 1785:
first derived this formula by showing that the volume inside a sphere is twice the volume between the sphere and the
87: 5153: 4121:
surface that lacks boundary or singularities with constant positive mean curvature. Other such immersed surfaces as
4907: 2880: ≈ 0.5236. For example, a sphere with diameter 1 m has 52.4% the volume of a cube with edge length 1 6582: 4006:
are equal. Umbilical points can be thought of as the points where the surface is closely approximated by a sphere.
3709: 2000: 4915: 6887: 6882: 5080: 4166:. The plane is the only other surface with a three-parameter family of transformations (translations along the 1114: 3143: 2955:
cylinder is area-preserving. Another approach to obtaining the formula comes from the fact that it equals the
3737: 1337:
is the equation of a plane. Thus, a plane may be thought of as a sphere of infinite radius whose center is a
6892: 4652:, the angle between its tangent and due North, is constant. Loxodromes project to straight lines under the 3786: 3712:, it can be seen that two spheres intersect in a circle and the plane containing that circle is called the 6587: 4450: 6902: 6748: 5838: 4665: 1382: 6216: 2089: 6897: 6473:
The Mathematical Universe: An Alphabetical Journey Through the Great Proofs, Problems and Personalities
5858: 5642: 4782: 4753: 3965:
of the boundary of its orthogonal projection on to a plane. Each of these properties implies the other.
4606:
More complicated surfaces may intersect a sphere in circles, too: the intersection of a sphere with a
3311: 5651: 3550:{\displaystyle A=\int _{0}^{2\pi }\int _{0}^{\pi }r^{2}\sin \theta \,d\theta \,d\varphi =4\pi r^{2}.} 1290: 430:
includes the sphere: a closed ball is the union of the open ball and the sphere, and a sphere is the
17: 54: 6784: 6552: 5935: 4510: 4216: 4099:
The sphere has the smallest total mean curvature among all convex solids with a given surface area.
4081: 3368: 2906: 1794: 5654:
was the first to state that, for a given surface area, the sphere is the solid of maximum volume.
4239:
shows that the shortest path between two points lying on the sphere is the shorter segment of the
6857: 6788: 6120: 5808: 5479: 4549: 4533: 3680: 183: 31: 1216: 1190: 1067: 1011: 5823: 5744: 4895:
If a sphere is intersected by another surface, there may be more complicated spherical curves.
4318: 4259: 1439: 419: 6478: 6399: 5990:
The distance between two non-distinct points (i.e., a point and itself) on the sphere is zero.
4707: 1626: 6724: 6666: 5903: 5701:
experiment, and differs in shape from a perfect sphere by no more than 40 atoms (less than 10
5259: 4868: 4731: 4607: 4560: 4426: 4175: 3574: 3422: 2452: 1608: 1041: 6470: 5448: 1356: 326:, and spheres in this article have their center at the origin unless a center is mentioned. 284:
If a radius is extended through the center to the opposite side of the sphere, it creates a
6846: 6821: 6513: 6482: 5920: 5845:
self-portrait drawing illustrating reflection and the optical properties of a mirror sphere
5647: 5627: 5440: 4657: 4649: 4163: 3672: 1865: 1763:{\displaystyle V={\frac {4}{3}}\pi r^{3}={\frac {\pi }{6}}\ d^{3}\approx 0.5236\cdot d^{3}} 1263: 381: 77: 4227:. On the sphere, points are defined in the usual sense. The analogue of the "line" is the 335:
on the sphere has the same center and radius as the sphere, and divides it into two equal
8: 6816: 6810: 5930: 5873: 5444: 5074:
is not just one or two circles. It is the solution of the non-linear system of equations
4794: 4653: 4564: 4529: 4314: 4003: 3993: 3934: 3926: 3909: 3905: 2951:
first derived this formula from the fact that the projection to the lateral surface of a
2080: 1789: 1350: 503: 431: 173: 6486: 4861: 6711: 6320: 5914: 5614: 5563: 5552: 4786: 4661: 4597: 4552:
with possible self-intersections but without creating any creases, in a process called
4334: 4271: 4255: 4247: 4224: 4199: 4135: 1673: 447: 414: 387: 6058: 322:). For convenience, spheres are often taken to have their center at the origin of the 6917: 6912: 6690: 6517: 6506: 6490: 6471: 6455: 6403: 6348: 6327: 6179: 6153: 5813: 5774: 5764: 5633: 4537: 4441: 4345: 4310: 4275: 3980: 1813:
disks of infinitesimally small thickness stacked side by side and centered along the
1798: 1338: 659: 470: 458: 323: 288:. Like the radius, the length of a diameter is also called the diameter, and denoted 201: 187: 70: 30:
This article is about the concept in three-dimensional geometry. For other uses, see
6351: 6233: 5977:
It does not matter which direction is chosen, the distance is the sphere's radius ×
4857:
The intersection of a sphere with a quadratic cone whose vertex is the sphere center
3922: 1660: 6907: 6672: 6395: 6228: 5769: 5606: 5573: 4872: 4850: 4669: 4437: 4220: 4153:
The sphere is transformed into itself by a three-parameter family of rigid motions.
2828: 1802: 451: 355: 350: 236: 228: 212: 92: 3912:, which can be thought of as a sphere with infinite radius. These properties are: 6774: 5863: 5853: 5848: 5779: 5698: 5687: 5462:
The sphere is the inverse image of a one-point set under the continuous function
4879:
Many theorems relating to planar conic sections also extend to spherical conics.
4846: 4836: 4553: 4282: 4122: 4089: 4042: 4035: 3998: 3567: 1806: 655: 405: 345: 305: 220: 6736: 4536:
states that the hemisphere is the optimal (least area) isometric filling of the
4266:
are defined between great circles. Spherical trigonometry differs from ordinary
6372: 5898: 5888: 5784: 5759: 5730: 5285: 5238: 4422: 4349: 4330: 4295: 4104: 3721: 2456: 398: 165: 66: 5547:
If the center is a distinguished point that is considered to be the origin of
6876: 6837: 6793: 6779: 6677: 6315: 6068:. Vol. 25 (11th ed.). Cambridge University Press. pp. 647–648. 6053: 5908: 5868: 5803: 5754: 5456: 5452: 5437: 4842: 4518: 4514: 4050: 4025: 3962: 3958: 3901: 3725: 3671:; this is very similar to the traditional definition of a sphere as given in 256: 240: 146: 6182: 2862:
is the diameter of the sphere and also the length of a side of the cube and
48: 6684: 6617: 6422:
that the ratio of the resulting volumes would be the same as a given ratio.
5940: 5883: 5878: 5828: 5729:
Deck of playing cards illustrating engineering instruments, England, 1702.
5691: 5658: 5497: 5491: 4820: 4360: 4267: 4240: 4232: 4208: 4159: 4144: 3418: 2952: 2893: 1786: 331: 101: 6543:
Higher Geometry / An Introduction to Advanced Methods in Analytic Geometry
4002:. At an umbilic all the sectional curvatures are equal; in particular the 1810: 211:. Spheres and nearly-spherical shapes also appear in nature and industry. 5893: 5842: 5556: 5402: 4824: 4085: 312: 216: 208: 5709:
scientists had created even more nearly perfect spheres, accurate to 0.3
3866:
is also the equation of a sphere for arbitrary values of the parameters
2831:
in a cube can be approximated as 52.4% of the volume of the cube, since
5925: 5683: 5637: 5602: 4882: 4725: 4637: 4623: 4294:
segment it into one minor (i.e., shorter) and one major (i.e., longer)
4236: 3684: 2956: 2948: 1782: 4548:
Remarkably, it is possible to turn an ordinary sphere inside out in a
3637:{\displaystyle \mathrm {SSA} ={\frac {A}{V\rho }}={\frac {3}{r\rho }}} 6852: 6741: 6356: 6187: 5833: 5818: 5706: 5694: 5281: 5255: 4701: 4251: 4147:
is an example of a surface with constant negative Gaussian curvature.
4139: 4118: 4066: 3720:
The angle between two spheres at a real point of intersection is the
3699: 401: 377: 232: 224: 155: 4700:
Another kind of spherical spiral is the Clelia curve, for which the
4686: 4681: 4583: 6729: 5798: 5429: 5387: 5275: 4270:
in many respects. For example, the sum of the interior angles of a
4228: 4179: 3695: 3688: 3668: 3440: 654:
Since it can be expressed as a quadratic polynomial, a sphere is a
386:. Small circles on the sphere that are parallel to the equator are 285: 200:. The earliest known mentions of spheres appear in the work of the 161: 6434:
New Scientist | Technology | Roundest objects in the world created
6318:; Cohn-Vossen, Stephan (1952). "Eleven properties of the sphere". 6314: 4887: 267: 5662: 5595: 5263: 5262:. An ellipsoid bears the same relationship to the sphere that an 4084:. These properties define the sphere uniquely and can be seen in 3972: 3887: 3676: 3652: 372: 248: 4575: 3663:
A sphere can be constructed as the surface formed by rotating a
644:{\displaystyle (x-x_{0})^{2}+(y-y_{0})^{2}+(z-z_{0})^{2}=r^{2}.} 457:
Small spheres or balls are sometimes called spherules (e.g., in
5682:
An image of one of the most accurate human-made spheres, as it
5358: 4559:
The antipodal quotient of the sphere is the surface called the
4204: 3930: 3664: 2227:{\displaystyle V=\int _{-r}^{r}\pi \left(r^{2}-x^{2}\right)dx,} 1669: 443: 197: 169: 113: 3874:. The set of all spheres satisfying this equation is called a 3573:
The surface area relative to the mass of a ball is called the
3283:{\displaystyle {\frac {4}{3}}\pi r^{3}=\int _{0}^{r}A(r)\,dr.} 1933:
The total volume is the summation of all incremental volumes:
6643: 6057: 4263: 4046: 2520:{\displaystyle dV=r^{2}\sin \theta \,dr\,d\theta \,d\varphi } 998:{\displaystyle f(x,y,z)=a(x^{2}+y^{2}+z^{2})+2(bx+cy+dz)+e=0} 4628: 4587:
Coaxial intersection of a sphere and a cylinder: two circles
3694:
A sphere is uniquely determined by four points that are not
3293:
Differentiating both sides of this equation with respect to
1676:, but classically referred to as the volume of a sphere) is 5610: 5566:, even a large sphere may be an empty set. For example, in 5314:)-dimensional Euclidean space that are at a fixed distance 5067:{\displaystyle \;(y-y_{0})^{2}+z^{2}=a^{2},\;y_{0}\neq 0\;} 3996:. Any closed surface will have at least four points called 370:). The great circle equidistant to the poles is called the 252: 244: 3943:
The contours and plane sections of the sphere are circles.
6147: 5412:-sphere of unit radius centered at the origin is denoted 4414:{\displaystyle dA=r^{2}\sin \theta \,d\theta \,d\varphi } 4143:
boundary with constant, positive Gaussian curvature. The
3683:. Replacing the circle with an ellipse rotated about its 397:
Mathematicians consider a sphere to be a two-dimensional
6346: 5636:. The volume and area formulas were first determined in 4038:
one sheet forms a curve and the other sheet is a surface
3577:
and can be expressed from the above stated equations as
3414:
is now considered to be the fixed radius of the sphere.
3077:
The total volume is the summation of all shell volumes:
2827:
For most practical purposes, the volume inside a sphere
1923:{\displaystyle \delta V\approx \pi y^{2}\cdot \delta x.} 6618:
Compact topological surfaces and their immersions in 3D
5705:
nm) of thickness. It was announced on 1 July 2008 that
4853:
curve which can be defined in several equivalent ways.
304:. Two points on the sphere connected by a diameter are 5968:
is being considered as a variable in this computation.
5625:
The geometry of the sphere was studied by the Greeks.
5322:
is, as before, a positive real number. In particular:
5280:
Spheres can be generalized to spaces of any number of
1980:{\displaystyle V\approx \sum \pi y^{2}\cdot \delta x.} 376:. Great circles through the poles are called lines of 358:). The sphere-axis intersection defines two antipodal 5156: 5083: 4986: 4918: 4797: 4756: 4734: 4710: 4453: 4368: 3789: 3586: 3452: 3371: 3314: 3216: 3146: 3086: 3030: 2909: 2539: 2467: 2246: 2154: 2092: 2003: 1942: 1885: 1685: 1629: 1451: 1385: 1359: 1293: 1266: 1219: 1193: 1117: 1070: 1044: 1014: 874: 685: 531: 422:
that includes the volume contained by the sphere. An
207:
The sphere is a fundamental object in many fields of
4883:
Intersection of a sphere with a more general surface
4781:. Clelia curves project to straight lines under the 4509:
This equation reflects that the position vector and
4131:
The sphere has constant positive Gaussian curvature.
3691:; rotated about the minor axis, an oblate spheroid. 2975:
is simply the product of the surface area at radius
1607:
The symbols used here are the same as those used in
434:
of a (closed or open) ball. The distinction between
219:
take a spherical shape in equilibrium. The Earth is
4819:) is a special case. Clelia curves approximate the 4188: 3067:{\displaystyle \delta V\approx A(r)\cdot \delta r.} 3002:) equals the product of the surface area at radius 2963:because the total volume inside a sphere of radius 6535:(Third American ed.), Oxford University Press 6505: 6319: 6173: 6171: 6169: 5226: 5141: 5066: 4972: 4809: 4771: 4740: 4716: 4610:whose axis contains the center of the sphere (are 4498: 4413: 4182:are the only surfaces with a one-parameter family. 3855: 3636: 3549: 3399: 3351: 3282: 3192: 3122: 3066: 2937: 2811: 2519: 2440: 2226: 2134: 2052: 1979: 1922: 1762: 1635: 1596: 1430: 1371: 1303: 1279: 1252: 1205: 1175: 1103: 1056: 1026: 997: 854: 643: 4567:with antipodal points of the equator identified. 4088:: a soap bubble will enclose a fixed volume, and 3953:The sphere has constant width and constant girth. 3123:{\displaystyle V\approx \sum A(r)\cdot \delta r.} 1183:and the equation is said to be the equation of a 6874: 3710:common solutions of the equations of two spheres 6550: 6177: 6166: 4867:The locus of points whose sum or difference of 4517:to each other. Furthermore, the outward-facing 4274:always exceeds 180 degrees. Also, any two 3780:are the equations of two distinct spheres then 5334:: a 0-sphere consists of two discrete points, 5227:{\displaystyle (y-y_{0})^{2}+z^{2}-a^{2}=0\ .} 4436:A sphere of any radius centered at zero is an 4062:All geodesics of the sphere are closed curves. 4015:The sphere does not have a surface of centers. 2959:of the formula for the volume with respect to 255:used in sports and toys are spherical, as are 6603: 6221:Bulletin of the American Mathematical Society 5390:is a sphere in 4-dimensional Euclidean space. 4912:The intersection of the sphere with equation 3738:Pencil (mathematics) § Pencil of spheres 3702:points determine a unique circle in a plane. 3658: 4024:, and the set of all such centers forms the 2053:{\displaystyle V=\int _{-r}^{r}\pi y^{2}dx.} 1864:) equals the product of the cross-sectional 6326:(2nd ed.). Chelsea. pp. 215–231. 4973:{\displaystyle \;x^{2}+y^{2}+z^{2}=r^{2}\;} 4864:whose axis passes through the sphere center 4660:which are aligned directly North–South and 3882: 1260:is an equation of a sphere whose center is 6610: 6596: 6578:Mathematica/Uniform Spherical Distribution 6079: 6077: 6075: 6025: 6023: 5318:from a central point of that space, where 5063: 5046: 4987: 4969: 4919: 4521:is equal to the position vector scaled by 3947:This property defines the sphere uniquely. 2237:which can be evaluated to give the result 1793:the circumscribing cylinder, and applying 1672:inside a sphere (that is, the volume of a 1540: 1491: 47: 6530: 6232: 6202: 6107: 5478:is also bounded, so it is compact by the 5142:{\displaystyle x^{2}+y^{2}+z^{2}-r^{2}=0} 4603:sphere: others are called small circles. 4483: 4470: 4457: 4404: 4397: 3518: 3511: 3439:. The total area can thus be obtained by 3270: 3180: 2765: 2719: 2707: 2637: 2630: 2618: 2510: 2503: 2496: 1797:. This formula can also be derived using 1589: 1176:{\displaystyle P_{0}=(x_{0},y_{0},z_{0})} 6503: 6392:Oxford Research Encyclopedia of Classics 6284: 6095: 6052: 4886: 4685: 4627: 4582: 4574: 4324: 4203: 3886: 3193:{\displaystyle V=\int _{0}^{r}A(r)\,dr.} 1994:approaches zero, this equation becomes: 1659: 266: 6400:10.1093/acrefore/9780199381135.013.8161 6143: 6141: 6121:"The volume of a sphere – Math Central" 6072: 6020: 5947: 4113:The sphere has constant mean curvature. 3988:and the curvature of this curve is the 3137:approaches zero this equation becomes: 27:Set of points equidistant from a center 14: 6875: 6468: 6449: 6386:Fried, Michael N. (25 February 2019). 6302: 6278: 6266: 6254: 6029: 6013:, Henry George Liddell, Robert Scott, 5715:to find a new global standard kilogram 4563:, which can also be thought of as the 3933:. This second part also holds for the 3675:. Since a circle is a special type of 2451:An alternative formula is found using 1849:Proof of sphere volume, using calculus 6591: 6540: 6385: 6347: 6290: 6178: 6083: 5713:nm, as part of an international hunt 5690:in the background. This sphere was a 4860:The intersection of a sphere with an 4579:Plane section of a sphere: one circle 4570: 4193: 3856:{\displaystyle sf(x,y,z)+tg(x,y,z)=0} 3667:one half revolution about any of its 2987:Proof of surface area, using calculus 6148:E.J. Borowski; J.M. Borwein (1989). 6138: 6048: 6046: 6044: 6042: 6040: 6038: 4891:General intersection sphere-cylinder 4499:{\displaystyle x\,dx+y\,dy+z\,dz=0.} 4352:introduces some form of distortion. 3731: 426:excludes the sphere itself, while a 408:. They draw a distinction between a 262: 5447:. A topological sphere need not be 4830: 4301:have the minor arc's length be the 4278:spherical triangles are congruent. 2079:to the origin; hence, applying the 2067:, a right-angled triangle connects 1431:{\displaystyle (x_{0},y_{0},z_{0})} 1318:in the above equation is zero then 1008:has no real points as solutions if 251:smoothly in any direction, so most 24: 6443: 5613:is a sphere in geometry using the 5451:; if it is smooth, it need not be 5421:and is often referred to as "the" 5375:: a 2-sphere is an ordinary sphere 5244: 3594: 3591: 3588: 3362:This is generally abbreviated as: 2135:{\displaystyle y^{2}=r^{2}-x^{2}.} 1655: 176:that are all at the same distance 25: 6929: 6571: 6551:John C. Polking (15 April 1999). 6150:Collins Dictionary of Mathematics 6035: 5917:of a curve of constant precession 5745:Ball (mathematics) § Regions 5269: 4772:{\displaystyle \varphi =c\theta } 2979:and the infinitesimal thickness. 1664:Sphere and circumscribed cylinder 1034:and is called the equation of an 6508:Advanced Engineering Mathematics 6450:Albert, Abraham Adrian (2016) , 5722: 5675: 5485: 4675: 4668:, such a loxodrome is a kind of 4309:Spherical geometry is a form of 4189:Treatment by area of mathematics 3961:. The girth of a surface is the 3679:, a sphere is a special type of 3570:locally minimizes surface area. 3352:{\displaystyle 4\pi r^{2}=A(r).} 3017:) and the thickness of a shell ( 1837:, assuming the sphere of radius 271:Two orthogonal radii of a sphere 6427: 6379: 6365: 6340: 6308: 6296: 6272: 6260: 6248: 6234:10.1090/S0002-9904-1978-14553-4 6208: 6196: 5984: 5971: 5959: 4980:and the cylinder with equation 4862:elliptic or hyperbolic cylinder 3655:(the ratio of mass to volume). 2887: 1781:is the diameter of the sphere. 1304:{\displaystyle {\sqrt {\rho }}} 781: 749: 717: 418:, which is a three-dimensional 235:. Manufactured items including 6217:"The isoperimetric inequality" 6152:. Collins. pp. 141, 149. 6113: 6101: 6089: 6004: 5632:its diameter, probably due to 5177: 5157: 5008: 4988: 4748:are in a linear relationship, 3844: 3826: 3814: 3796: 3687:, the shape becomes a prolate 3343: 3337: 3267: 3261: 3177: 3171: 3105: 3099: 3049: 3043: 2145:Using this substitution gives 1425: 1386: 1241: 1223: 1170: 1131: 1092: 1074: 980: 953: 944: 905: 896: 878: 616: 596: 584: 564: 552: 532: 315:is a sphere with unit radius ( 247:are based on spheres. Spheres 221:often approximated as a sphere 168:analogue to a two-dimensional 13: 1: 6541:Woods, Frederick S. (1961) , 6214: 5997: 5249: 4421:. This can be found from the 4291:lie on a unique great circle, 4125:have constant mean curvature. 3400:{\displaystyle A=4\pi r^{2},} 2938:{\displaystyle A=4\pi r^{2}.} 1650: 1344: 6583:Surface area of sphere proof 6553:"The Geometry of the Sphere" 6477:. New York: Wiley. pp.  6322:Geometry and the Imagination 5455:to the Euclidean sphere (an 4908:Sphere–cylinder intersection 4656:. Two special cases are the 4617: 3979:At any point on a surface a 3898:Geometry and the Imagination 464: 202:ancient Greek mathematicians 172:. Formally, a sphere is the 7: 5839:Hand with Reflecting Sphere 5791: 5436:-sphere is an example of a 5307:, is the set of points in ( 4666:spherical coordinate system 4543: 4305:between them on the sphere. 3971:All points of a sphere are 3892:will be an umbilical point. 1841:is centered at the origin. 1805:) to sum the volumes of an 1438:can be parameterized using 1353:for the sphere with radius 231:is an important concept in 10: 6934: 6512:(3rd ed.), New York: 5859:Homotopy groups of spheres 5742: 5738: 5668: 5643:On the Sphere and Cylinder 5620: 5489: 5273: 4905: 4834: 4783:equirectangular projection 4679: 4621: 4595: 4591: 4243:that includes the points. 4197: 3735: 3659:Other geometric properties 3421:on the sphere is given in 2998:, the incremental volume ( 2884:m, or about 0.524 m. 1860:, the incremental volume ( 1253:{\displaystyle f(x,y,z)=0} 1206:{\displaystyle \rho >0} 1104:{\displaystyle f(x,y,z)=0} 1027:{\displaystyle \rho <0} 186:. That given point is the 149: 29: 6830: 6802: 6767: 6758: 6704: 6659: 6630: 6623: 6215:Osserman, Robert (1978). 5588:can be written as sum of 1668:In three dimensions, the 112: 100: 86: 76: 62: 46: 41: 6504:Kreyszig, Erwin (1972), 6469:Dunham, William (1997). 5952: 5936:Volume-equivalent radius 4717:{\displaystyle \varphi } 4217:Euclidean plane geometry 4082:isoperimetric inequality 4053:both sheets form curves. 3883:Properties of the sphere 1636:{\displaystyle \varphi } 6749:Sphere with three holes 6452:Solid Analytic Geometry 6065:Encyclopædia Britannica 6015:A Greek-English Lexicon 5809:Alexander horned sphere 5511:, the sphere of center 4741:{\displaystyle \theta } 4550:three-dimensional space 4534:filling area conjecture 4337:at each point equal to 4117:The sphere is the only 3681:ellipsoid of revolution 1440:trigonometric functions 1187:. Finally, in the case 1064:, the only solution of 1057:{\displaystyle \rho =0} 473:, a sphere with center 184:three-dimensional space 32:Sphere (disambiguation) 6533:Mathematical Snapshots 6531:Steinhaus, H. (1969), 6125:mathcentral.uregina.ca 5824:Directional statistics 5228: 5143: 5068: 4974: 4892: 4869:great-circle distances 4811: 4773: 4742: 4718: 4697: 4633: 4588: 4580: 4513:at a point are always 4500: 4415: 4319:non-Euclidean geometry 4313:, which together with 4260:spherical trigonometry 4215:The basic elements of 4212: 4176:surfaces of revolution 3893: 3857: 3638: 3551: 3401: 3353: 3284: 3194: 3124: 3068: 2939: 2896:of a sphere of radius 2813: 2521: 2442: 2228: 2136: 2054: 1981: 1924: 1764: 1665: 1637: 1598: 1432: 1373: 1372:{\displaystyle r>0} 1305: 1281: 1254: 1207: 1177: 1105: 1058: 1028: 999: 856: 645: 420:manifold with boundary 272: 182:from a given point in 55:perspective projection 6888:Differential topology 6883:Differential geometry 6667:Real projective plane 6652:Pretzel (genus 3) ... 6557:www.math.csi.cuny.edu 5904:Spherical coordinates 5576:, a sphere of radius 5522:is the set of points 5496:More generally, in a 5401:are sometimes called 5260:affine transformation 5229: 5144: 5069: 4975: 4890: 4812: 4774: 4743: 4719: 4689: 4631: 4608:surface of revolution 4586: 4578: 4561:real projective plane 4501: 4427:spherical coordinates 4416: 4325:Differential geometry 4207: 3890: 3858: 3639: 3575:specific surface area 3552: 3423:spherical coordinates 3402: 3354: 3285: 3195: 3125: 3069: 2940: 2814: 2522: 2453:spherical coordinates 2443: 2229: 2137: 2055: 1982: 1925: 1795:Cavalieri's principle 1765: 1663: 1638: 1609:spherical coordinates 1599: 1433: 1374: 1306: 1282: 1280:{\displaystyle P_{0}} 1255: 1208: 1178: 1106: 1059: 1029: 1000: 857: 669:be real numbers with 646: 404:in three-dimensional 275:As mentioned earlier 270: 6822:Euler characteristic 5948:Notes and references 5921:Spherical polyhedron 5648:method of exhaustion 5582:is nonempty only if 5441:topological manifold 5154: 5081: 4984: 4916: 4795: 4754: 4732: 4708: 4451: 4366: 4164:rotation group SO(3) 4004:principal curvatures 3994:principal curvatures 3787: 3584: 3450: 3369: 3312: 3214: 3144: 3084: 3028: 2994:At any given radius 2907: 2537: 2465: 2244: 2152: 2090: 2001: 1940: 1883: 1683: 1627: 1449: 1383: 1357: 1291: 1287:and whose radius is 1264: 1217: 1191: 1115: 1068: 1042: 1012: 872: 683: 529: 6893:Elementary geometry 6487:1994muaa.book.....D 5931:Tennis ball theorem 5874:Napkin ring problem 5480:Heine–Borel theorem 5472:, so it is closed; 4845:on the sphere is a 4810:{\displaystyle c=1} 4690:Clelia spiral with 4654:Mercator projection 4571:Curves on a sphere 4565:Northern Hemisphere 4530:Riemannian geometry 4355:A sphere of radius 4315:hyperbolic geometry 4246:Many theorems from 3927:Apollonius of Perga 3906:Stephan Cohn-Vossen 3491: 3476: 3417:Alternatively, the 3257: 3167: 2749: 2682: 2667: 2593: 2578: 2563: 2313: 2178: 2081:Pythagorean theorem 2027: 1872:and its thickness ( 1615:is constant, while 1351:parametric equation 388:circles of latitude 190:of the sphere, and 6903:Homogeneous spaces 6649:Number 8 (genus 2) 6349:Weisstein, Eric W. 6180:Weisstein, Eric W. 5915:tangent indicatrix 5615:Chebyshev distance 5357:: a 1-sphere is a 5266:does to a circle. 5224: 5139: 5064: 4970: 4893: 4807: 4769: 4738: 4714: 4698: 4634: 4598:Circle of a sphere 4589: 4581: 4496: 4411: 4335:Gaussian curvature 4272:spherical triangle 4256:parallel postulate 4248:classical geometry 4213: 4200:Spherical geometry 4194:Spherical geometry 4136:Gaussian curvature 3894: 3853: 3634: 3547: 3477: 3459: 3397: 3349: 3280: 3243: 3190: 3153: 3120: 3064: 2935: 2809: 2735: 2668: 2653: 2579: 2564: 2546: 2517: 2438: 2256: 2224: 2161: 2132: 2050: 2010: 1977: 1920: 1777:is the radius and 1760: 1666: 1643:varies from 0 to 2 1633: 1594: 1592: 1428: 1369: 1301: 1277: 1250: 1203: 1173: 1101: 1054: 1024: 995: 865:Then the equation 852: 641: 273: 6898:Elementary shapes 6870: 6869: 6866: 6865: 6700: 6699: 6523:978-0-471-50728-4 6496:978-0-471-17661-9 6461:978-0-486-81026-3 6409:978-0-19-938113-5 6352:"Spheric section" 6333:978-0-8284-1087-8 6159:978-0-00-434347-1 5913:Spherical helix, 5814:Celestial spheres 5775:Spherical segment 5765:Spherical polygon 5634:Eudoxus of Cnidus 5628:Euclid's Elements 5241:and the diagram) 5220: 4823:of satellites in 4728:(or polar angle) 4538:Riemannian circle 4442:differential form 4440:of the following 4346:Theorema Egregium 4344:. As per Gauss's 4311:elliptic geometry 4303:shortest distance 3876:pencil of spheres 3732:Pencil of spheres 3708:By examining the 3673:Euclid's Elements 3632: 3614: 3562: 3561: 3301:as a function of 3225: 2824: 2823: 2791: 2779: 2420: 2402: 2353: 2293: 1799:integral calculus 1730: 1726: 1700: 1619:varies from 0 to 1339:point at infinity 1299: 847: 776: 744: 712: 660:algebraic surface 471:analytic geometry 459:Martian spherules 324:coordinate system 263:Basic terminology 166:three-dimensional 164:object that is a 139: 138: 71:Algebraic surface 16:(Redirected from 6925: 6785:Triangulatedness 6765: 6764: 6628: 6627: 6624:Without boundary 6612: 6605: 6598: 6589: 6588: 6567: 6565: 6563: 6546: 6536: 6526: 6511: 6500: 6476: 6464: 6437: 6431: 6425: 6424: 6418: 6416: 6388:"conic sections" 6383: 6377: 6376: 6369: 6363: 6362: 6361: 6344: 6338: 6337: 6325: 6312: 6306: 6300: 6294: 6288: 6282: 6276: 6270: 6264: 6258: 6252: 6246: 6245: 6243: 6241: 6236: 6212: 6206: 6200: 6194: 6193: 6192: 6175: 6164: 6163: 6145: 6136: 6135: 6133: 6131: 6117: 6111: 6105: 6099: 6093: 6087: 6081: 6070: 6069: 6061: 6050: 6033: 6027: 6018: 6008: 5991: 5988: 5982: 5975: 5969: 5967: 5963: 5770:Spherical sector 5726: 5712: 5704: 5679: 5607:taxicab geometry 5593: 5587: 5581: 5574:Euclidean metric 5571: 5550: 5543: 5525: 5521: 5514: 5510: 5477: 5471: 5469: 5435: 5424: 5420: 5419: 5411: 5400: 5385: 5384: 5374: 5373: 5356: 5355: 5346: 5340: 5333: 5332: 5321: 5317: 5313: 5306: 5305: 5295: 5290: 5233: 5231: 5230: 5225: 5218: 5211: 5210: 5198: 5197: 5185: 5184: 5175: 5174: 5148: 5146: 5145: 5140: 5132: 5131: 5119: 5118: 5106: 5105: 5093: 5092: 5073: 5071: 5070: 5065: 5056: 5055: 5042: 5041: 5029: 5028: 5016: 5015: 5006: 5005: 4979: 4977: 4976: 4971: 4968: 4967: 4955: 4954: 4942: 4941: 4929: 4928: 4841:The analog of a 4831:Spherical conics 4818: 4816: 4814: 4813: 4808: 4780: 4778: 4776: 4775: 4770: 4747: 4745: 4744: 4739: 4723: 4721: 4720: 4715: 4696: 4670:spherical spiral 4648:is a path whose 4524: 4505: 4503: 4502: 4497: 4438:integral surface 4432: 4420: 4418: 4417: 4412: 4387: 4386: 4358: 4343: 4329:The sphere is a 4284:antipodal points 4254:, including the 4173: 4169: 4123:minimal surfaces 4080:It follows from 4036:channel surfaces 3999:umbilical points 3990:normal curvature 3981:normal direction 3873: 3869: 3862: 3860: 3859: 3854: 3779: 3760: 3650: 3643: 3641: 3640: 3635: 3633: 3631: 3620: 3615: 3613: 3602: 3597: 3556: 3554: 3553: 3548: 3543: 3542: 3501: 3500: 3490: 3485: 3475: 3467: 3438: 3413: 3406: 3404: 3403: 3398: 3393: 3392: 3358: 3356: 3355: 3350: 3330: 3329: 3304: 3300: 3296: 3289: 3287: 3286: 3281: 3256: 3251: 3239: 3238: 3226: 3218: 3206: 3199: 3197: 3196: 3191: 3166: 3161: 3136: 3133:In the limit as 3129: 3127: 3126: 3121: 3073: 3071: 3070: 3065: 3020: 3016: 3005: 3001: 2997: 2983: 2982: 2978: 2974: 2970: 2966: 2962: 2944: 2942: 2941: 2936: 2931: 2930: 2899: 2883: 2879: 2877: 2876: 2873: 2870: 2869: 2861: 2857: 2853: 2851: 2850: 2847: 2844: 2843: 2818: 2816: 2815: 2810: 2805: 2804: 2792: 2784: 2777: 2776: 2764: 2763: 2762: 2748: 2743: 2718: 2697: 2696: 2695: 2681: 2676: 2666: 2661: 2629: 2608: 2607: 2606: 2592: 2587: 2577: 2572: 2562: 2554: 2526: 2524: 2523: 2518: 2486: 2485: 2447: 2445: 2444: 2439: 2434: 2433: 2421: 2413: 2408: 2404: 2403: 2398: 2397: 2388: 2383: 2382: 2359: 2355: 2354: 2349: 2348: 2339: 2334: 2333: 2312: 2307: 2299: 2295: 2294: 2289: 2288: 2279: 2271: 2270: 2233: 2231: 2230: 2225: 2214: 2210: 2209: 2208: 2196: 2195: 2177: 2172: 2141: 2139: 2138: 2133: 2128: 2127: 2115: 2114: 2102: 2101: 2078: 2074: 2070: 2066: 2059: 2057: 2056: 2051: 2040: 2039: 2026: 2021: 1993: 1990:In the limit as 1986: 1984: 1983: 1978: 1964: 1963: 1929: 1927: 1926: 1921: 1907: 1906: 1875: 1871: 1866:area of the disk 1863: 1859: 1845: 1844: 1840: 1836: 1826: 1816: 1803:disk integration 1780: 1776: 1769: 1767: 1766: 1761: 1759: 1758: 1740: 1739: 1728: 1727: 1719: 1714: 1713: 1701: 1693: 1646: 1642: 1640: 1639: 1634: 1622: 1618: 1614: 1603: 1601: 1600: 1595: 1593: 1573: 1572: 1524: 1523: 1475: 1474: 1437: 1435: 1434: 1429: 1424: 1423: 1411: 1410: 1398: 1397: 1378: 1376: 1375: 1370: 1336: 1317: 1310: 1308: 1307: 1302: 1300: 1295: 1286: 1284: 1283: 1278: 1276: 1275: 1259: 1257: 1256: 1251: 1212: 1210: 1209: 1204: 1182: 1180: 1179: 1174: 1169: 1168: 1156: 1155: 1143: 1142: 1127: 1126: 1110: 1108: 1107: 1102: 1063: 1061: 1060: 1055: 1036:imaginary sphere 1033: 1031: 1030: 1025: 1004: 1002: 1001: 996: 943: 942: 930: 929: 917: 916: 861: 859: 858: 853: 848: 846: 845: 836: 826: 825: 813: 812: 800: 799: 789: 777: 772: 764: 759: 758: 745: 740: 732: 727: 726: 713: 708: 700: 695: 694: 675: 668: 650: 648: 647: 642: 637: 636: 624: 623: 614: 613: 592: 591: 582: 581: 560: 559: 550: 549: 521: 501: 497: 356:axis of rotation 321: 306:antipodal points 303: 293: 280: 237:pressure vessels 229:celestial sphere 196:is the sphere's 195: 181: 159: 153: 135: 133: 131: 130: 127: 124: 108: 95: 51: 39: 38: 21: 6933: 6932: 6928: 6927: 6926: 6924: 6923: 6922: 6873: 6872: 6871: 6862: 6826: 6803:Characteristics 6798: 6760: 6754: 6696: 6655: 6619: 6616: 6574: 6561: 6559: 6524: 6497: 6462: 6446: 6444:Further reading 6441: 6440: 6432: 6428: 6414: 6412: 6410: 6384: 6380: 6371: 6370: 6366: 6345: 6341: 6334: 6313: 6309: 6301: 6297: 6289: 6285: 6277: 6273: 6265: 6261: 6253: 6249: 6239: 6237: 6213: 6209: 6201: 6197: 6176: 6167: 6160: 6146: 6139: 6129: 6127: 6119: 6118: 6114: 6106: 6102: 6098:, p. 342). 6094: 6090: 6082: 6073: 6051: 6036: 6028: 6021: 6009: 6005: 6000: 5995: 5994: 5989: 5985: 5976: 5972: 5965: 5964: 5960: 5955: 5950: 5945: 5864:Homotopy sphere 5854:Homology sphere 5849:Hoberman sphere 5794: 5789: 5780:Spherical wedge 5747: 5741: 5734: 5727: 5718: 5710: 5702: 5699:Gravity Probe B 5680: 5671: 5623: 5605:is a sphere in 5589: 5583: 5577: 5567: 5548: 5527: 5523: 5516: 5512: 5500: 5494: 5488: 5473: 5465: 5463: 5433: 5422: 5417: 5413: 5409: 5395: 5382: 5378: 5371: 5367: 5353: 5349: 5342: 5335: 5330: 5326: 5319: 5315: 5308: 5303: 5299: 5293: 5288: 5278: 5272: 5252: 5247: 5245:Generalizations 5206: 5202: 5193: 5189: 5180: 5176: 5170: 5166: 5155: 5152: 5151: 5127: 5123: 5114: 5110: 5101: 5097: 5088: 5084: 5082: 5079: 5078: 5051: 5047: 5037: 5033: 5024: 5020: 5011: 5007: 5001: 4997: 4985: 4982: 4981: 4963: 4959: 4950: 4946: 4937: 4933: 4924: 4920: 4917: 4914: 4913: 4910: 4902:sphere–cylinder 4885: 4871:from a pair of 4847:spherical conic 4839: 4837:Spherical conic 4833: 4796: 4793: 4792: 4790: 4787:Viviani's curve 4755: 4752: 4751: 4749: 4733: 4730: 4729: 4709: 4706: 4705: 4691: 4684: 4678: 4626: 4620: 4600: 4594: 4573: 4554:sphere eversion 4546: 4522: 4452: 4449: 4448: 4433:held constant. 4430: 4382: 4378: 4367: 4364: 4363: 4356: 4338: 4327: 4202: 4196: 4191: 4171: 4167: 4090:surface tension 3986:normal section, 3885: 3871: 3867: 3788: 3785: 3784: 3762: 3743: 3740: 3734: 3661: 3648: 3624: 3619: 3606: 3601: 3587: 3585: 3582: 3581: 3568:surface tension 3563: 3538: 3534: 3496: 3492: 3486: 3481: 3468: 3463: 3451: 3448: 3447: 3426: 3411: 3388: 3384: 3370: 3367: 3366: 3325: 3321: 3313: 3310: 3309: 3302: 3298: 3294: 3252: 3247: 3234: 3230: 3217: 3215: 3212: 3211: 3204: 3162: 3157: 3145: 3142: 3141: 3134: 3085: 3082: 3081: 3029: 3026: 3025: 3018: 3007: 3003: 2999: 2995: 2988: 2976: 2972: 2968: 2964: 2960: 2926: 2922: 2908: 2905: 2904: 2897: 2890: 2881: 2874: 2871: 2867: 2866: 2865: 2863: 2859: 2848: 2845: 2841: 2840: 2839: 2837: 2832: 2825: 2800: 2796: 2783: 2769: 2758: 2754: 2750: 2744: 2739: 2711: 2691: 2687: 2683: 2677: 2672: 2662: 2657: 2622: 2602: 2598: 2594: 2588: 2583: 2573: 2568: 2555: 2550: 2538: 2535: 2534: 2481: 2477: 2466: 2463: 2462: 2429: 2425: 2412: 2393: 2389: 2387: 2378: 2374: 2370: 2366: 2344: 2340: 2338: 2329: 2325: 2324: 2320: 2308: 2300: 2284: 2280: 2278: 2266: 2262: 2261: 2257: 2245: 2242: 2241: 2204: 2200: 2191: 2187: 2186: 2182: 2173: 2165: 2153: 2150: 2149: 2123: 2119: 2110: 2106: 2097: 2093: 2091: 2088: 2087: 2076: 2072: 2068: 2064: 2035: 2031: 2022: 2014: 2002: 1999: 1998: 1991: 1959: 1955: 1941: 1938: 1937: 1902: 1898: 1884: 1881: 1880: 1873: 1869: 1861: 1857: 1850: 1838: 1828: 1818: 1814: 1807:infinite number 1778: 1774: 1754: 1750: 1735: 1731: 1718: 1709: 1705: 1692: 1684: 1681: 1680: 1658: 1656:Enclosed volume 1653: 1644: 1628: 1625: 1624: 1620: 1616: 1612: 1591: 1590: 1568: 1564: 1557: 1551: 1550: 1519: 1515: 1508: 1502: 1501: 1470: 1466: 1459: 1452: 1450: 1447: 1446: 1419: 1415: 1406: 1402: 1393: 1389: 1384: 1381: 1380: 1358: 1355: 1354: 1347: 1319: 1315: 1294: 1292: 1289: 1288: 1271: 1267: 1265: 1262: 1261: 1218: 1215: 1214: 1192: 1189: 1188: 1164: 1160: 1151: 1147: 1138: 1134: 1122: 1118: 1116: 1113: 1112: 1069: 1066: 1065: 1043: 1040: 1039: 1013: 1010: 1009: 938: 934: 925: 921: 912: 908: 873: 870: 869: 841: 837: 821: 817: 808: 804: 795: 791: 790: 788: 765: 763: 754: 750: 733: 731: 722: 718: 701: 699: 690: 686: 684: 681: 680: 670: 666: 656:quadric surface 632: 628: 619: 615: 609: 605: 587: 583: 577: 573: 555: 551: 545: 541: 530: 527: 526: 507: 499: 495: 488: 481: 474: 467: 406:Euclidean space 354:(as in Earth's 346:figure of Earth 316: 308:of each other. 295: 289: 276: 265: 191: 177: 128: 125: 122: 121: 119: 118: 106: 93: 69: 58: 35: 28: 23: 22: 15: 12: 11: 5: 6931: 6921: 6920: 6915: 6910: 6905: 6900: 6895: 6890: 6885: 6868: 6867: 6864: 6863: 6861: 6860: 6855: 6849: 6843: 6840: 6834: 6832: 6828: 6827: 6825: 6824: 6819: 6814: 6806: 6804: 6800: 6799: 6797: 6796: 6791: 6782: 6777: 6771: 6769: 6762: 6756: 6755: 6753: 6752: 6746: 6745: 6744: 6734: 6733: 6732: 6727: 6719: 6718: 6717: 6708: 6706: 6702: 6701: 6698: 6697: 6695: 6694: 6691:Dyck's surface 6688: 6682: 6681: 6680: 6675: 6663: 6661: 6660:Non-orientable 6657: 6656: 6654: 6653: 6650: 6647: 6641: 6634: 6632: 6625: 6621: 6620: 6615: 6614: 6607: 6600: 6592: 6586: 6585: 6580: 6573: 6572:External links 6570: 6569: 6568: 6548: 6538: 6528: 6522: 6501: 6495: 6466: 6460: 6445: 6442: 6439: 6438: 6426: 6408: 6378: 6364: 6339: 6332: 6316:Hilbert, David 6307: 6295: 6283: 6271: 6259: 6247: 6207: 6203:Steinhaus 1969 6195: 6165: 6158: 6137: 6112: 6108:Steinhaus 1969 6100: 6096:Kreyszig (1972 6088: 6071: 6059:"Sphere"  6056:, ed. (1911). 6054:Chisholm, Hugh 6034: 6019: 6002: 6001: 5999: 5996: 5993: 5992: 5983: 5970: 5957: 5956: 5954: 5951: 5949: 5946: 5944: 5943: 5938: 5933: 5928: 5923: 5918: 5911: 5906: 5901: 5899:Sphere packing 5896: 5891: 5889:Riemann sphere 5886: 5881: 5876: 5871: 5866: 5861: 5856: 5851: 5846: 5836: 5831: 5826: 5821: 5816: 5811: 5806: 5801: 5795: 5793: 5790: 5788: 5787: 5785:Spherical zone 5782: 5777: 5772: 5767: 5762: 5760:Spherical lune 5757: 5752: 5748: 5740: 5737: 5736: 5735: 5731:King of spades 5728: 5721: 5719: 5681: 5674: 5670: 5667: 5622: 5619: 5490:Main article: 5487: 5484: 5392: 5391: 5376: 5365: 5347: 5298:often denoted 5286:natural number 5274:Main article: 5271: 5270:Dimensionality 5268: 5251: 5248: 5246: 5243: 5239:implicit curve 5235: 5234: 5223: 5217: 5214: 5209: 5205: 5201: 5196: 5192: 5188: 5183: 5179: 5173: 5169: 5165: 5162: 5159: 5149: 5138: 5135: 5130: 5126: 5122: 5117: 5113: 5109: 5104: 5100: 5096: 5091: 5087: 5062: 5059: 5054: 5050: 5045: 5040: 5036: 5032: 5027: 5023: 5019: 5014: 5010: 5004: 5000: 4996: 4993: 4990: 4966: 4962: 4958: 4953: 4949: 4945: 4940: 4936: 4932: 4927: 4923: 4906:Main article: 4904: 4903: 4900: 4884: 4881: 4877: 4876: 4865: 4858: 4835:Main article: 4832: 4829: 4806: 4803: 4800: 4768: 4765: 4762: 4759: 4737: 4713: 4680:Main article: 4677: 4674: 4622:Main article: 4619: 4616: 4596:Main article: 4593: 4590: 4572: 4569: 4545: 4542: 4507: 4506: 4495: 4492: 4489: 4486: 4482: 4479: 4476: 4473: 4469: 4466: 4463: 4460: 4456: 4423:volume element 4410: 4407: 4403: 4400: 4396: 4393: 4390: 4385: 4381: 4377: 4374: 4371: 4350:map projection 4333:with constant 4331:smooth surface 4326: 4323: 4307: 4306: 4299: 4292: 4198:Main article: 4195: 4192: 4190: 4187: 4186: 4185: 4184: 4183: 4150: 4149: 4148: 4128: 4127: 4126: 4110: 4109: 4108: 4105:mean curvature 4096: 4095: 4094: 4073: 4072: 4071: 4059: 4058: 4057: 4054: 4039: 4032: 4029: 4012: 4011: 4010: 4007: 3968: 3967: 3966: 3950: 3949: 3948: 3940: 3939: 3938: 3896:In their book 3884: 3881: 3864: 3863: 3852: 3849: 3846: 3843: 3840: 3837: 3834: 3831: 3828: 3825: 3822: 3819: 3816: 3813: 3810: 3807: 3804: 3801: 3798: 3795: 3792: 3736:Main article: 3733: 3730: 3722:dihedral angle 3660: 3657: 3645: 3644: 3630: 3627: 3623: 3618: 3612: 3609: 3605: 3600: 3596: 3593: 3590: 3560: 3559: 3558: 3557: 3546: 3541: 3537: 3533: 3530: 3527: 3524: 3521: 3517: 3514: 3510: 3507: 3504: 3499: 3495: 3489: 3484: 3480: 3474: 3471: 3466: 3462: 3458: 3455: 3408: 3407: 3396: 3391: 3387: 3383: 3380: 3377: 3374: 3360: 3359: 3348: 3345: 3342: 3339: 3336: 3333: 3328: 3324: 3320: 3317: 3291: 3290: 3279: 3276: 3273: 3269: 3266: 3263: 3260: 3255: 3250: 3246: 3242: 3237: 3233: 3229: 3224: 3221: 3201: 3200: 3189: 3186: 3183: 3179: 3176: 3173: 3170: 3165: 3160: 3156: 3152: 3149: 3131: 3130: 3119: 3116: 3113: 3110: 3107: 3104: 3101: 3098: 3095: 3092: 3089: 3075: 3074: 3063: 3060: 3057: 3054: 3051: 3048: 3045: 3042: 3039: 3036: 3033: 2990: 2989: 2986: 2981: 2946: 2945: 2934: 2929: 2925: 2921: 2918: 2915: 2912: 2889: 2886: 2822: 2821: 2820: 2819: 2808: 2803: 2799: 2795: 2790: 2787: 2782: 2775: 2772: 2768: 2761: 2757: 2753: 2747: 2742: 2738: 2734: 2731: 2728: 2725: 2722: 2717: 2714: 2710: 2706: 2703: 2700: 2694: 2690: 2686: 2680: 2675: 2671: 2665: 2660: 2656: 2652: 2649: 2646: 2643: 2640: 2636: 2633: 2628: 2625: 2621: 2617: 2614: 2611: 2605: 2601: 2597: 2591: 2586: 2582: 2576: 2571: 2567: 2561: 2558: 2553: 2549: 2545: 2542: 2528: 2527: 2516: 2513: 2509: 2506: 2502: 2499: 2495: 2492: 2489: 2484: 2480: 2476: 2473: 2470: 2457:volume element 2449: 2448: 2437: 2432: 2428: 2424: 2419: 2416: 2411: 2407: 2401: 2396: 2392: 2386: 2381: 2377: 2373: 2369: 2365: 2362: 2358: 2352: 2347: 2343: 2337: 2332: 2328: 2323: 2319: 2316: 2311: 2306: 2303: 2298: 2292: 2287: 2283: 2277: 2274: 2269: 2265: 2260: 2255: 2252: 2249: 2235: 2234: 2223: 2220: 2217: 2213: 2207: 2203: 2199: 2194: 2190: 2185: 2181: 2176: 2171: 2168: 2164: 2160: 2157: 2143: 2142: 2131: 2126: 2122: 2118: 2113: 2109: 2105: 2100: 2096: 2061: 2060: 2049: 2046: 2043: 2038: 2034: 2030: 2025: 2020: 2017: 2013: 2009: 2006: 1988: 1987: 1976: 1973: 1970: 1967: 1962: 1958: 1954: 1951: 1948: 1945: 1931: 1930: 1919: 1916: 1913: 1910: 1905: 1901: 1897: 1894: 1891: 1888: 1852: 1851: 1848: 1843: 1771: 1770: 1757: 1753: 1749: 1746: 1743: 1738: 1734: 1725: 1722: 1717: 1712: 1708: 1704: 1699: 1696: 1691: 1688: 1657: 1654: 1652: 1649: 1632: 1605: 1604: 1588: 1585: 1582: 1579: 1576: 1571: 1567: 1563: 1560: 1558: 1556: 1553: 1552: 1549: 1546: 1543: 1539: 1536: 1533: 1530: 1527: 1522: 1518: 1514: 1511: 1509: 1507: 1504: 1503: 1500: 1497: 1494: 1490: 1487: 1484: 1481: 1478: 1473: 1469: 1465: 1462: 1460: 1458: 1455: 1454: 1427: 1422: 1418: 1414: 1409: 1405: 1401: 1396: 1392: 1388: 1368: 1365: 1362: 1346: 1343: 1298: 1274: 1270: 1249: 1246: 1243: 1240: 1237: 1234: 1231: 1228: 1225: 1222: 1202: 1199: 1196: 1172: 1167: 1163: 1159: 1154: 1150: 1146: 1141: 1137: 1133: 1130: 1125: 1121: 1100: 1097: 1094: 1091: 1088: 1085: 1082: 1079: 1076: 1073: 1053: 1050: 1047: 1023: 1020: 1017: 1006: 1005: 994: 991: 988: 985: 982: 979: 976: 973: 970: 967: 964: 961: 958: 955: 952: 949: 946: 941: 937: 933: 928: 924: 920: 915: 911: 907: 904: 901: 898: 895: 892: 889: 886: 883: 880: 877: 863: 862: 851: 844: 840: 835: 832: 829: 824: 820: 816: 811: 807: 803: 798: 794: 787: 784: 780: 775: 771: 768: 762: 757: 753: 748: 743: 739: 736: 730: 725: 721: 716: 711: 707: 704: 698: 693: 689: 652: 651: 640: 635: 631: 627: 622: 618: 612: 608: 604: 601: 598: 595: 590: 586: 580: 576: 572: 569: 566: 563: 558: 554: 548: 544: 540: 537: 534: 506:of all points 493: 486: 479: 466: 463: 399:closed surface 264: 261: 241:curved mirrors 137: 136: 116: 110: 109: 104: 98: 97: 90: 88:Symmetry group 84: 83: 80: 74: 73: 67:Smooth surface 64: 60: 59: 52: 44: 43: 26: 9: 6: 4: 3: 2: 6930: 6919: 6916: 6914: 6911: 6909: 6906: 6904: 6901: 6899: 6896: 6894: 6891: 6889: 6886: 6884: 6881: 6880: 6878: 6859: 6856: 6854: 6850: 6848: 6844: 6842:Making a hole 6841: 6839: 6838:Connected sum 6836: 6835: 6833: 6829: 6823: 6820: 6818: 6815: 6812: 6808: 6807: 6805: 6801: 6795: 6794:Orientability 6792: 6790: 6786: 6783: 6781: 6778: 6776: 6775:Connectedness 6773: 6772: 6770: 6766: 6763: 6757: 6750: 6747: 6743: 6740: 6739: 6738: 6735: 6731: 6728: 6726: 6723: 6722: 6720: 6715: 6714: 6713: 6710: 6709: 6707: 6705:With boundary 6703: 6693:(genus 3) ... 6692: 6689: 6686: 6683: 6679: 6678:Roman surface 6676: 6674: 6673:Boy's surface 6670: 6669: 6668: 6665: 6664: 6662: 6658: 6651: 6648: 6645: 6642: 6639: 6636: 6635: 6633: 6629: 6626: 6622: 6613: 6608: 6606: 6601: 6599: 6594: 6593: 6590: 6584: 6581: 6579: 6576: 6575: 6558: 6554: 6549: 6544: 6539: 6534: 6529: 6525: 6519: 6515: 6510: 6509: 6502: 6498: 6492: 6488: 6484: 6480: 6475: 6474: 6467: 6463: 6457: 6453: 6448: 6447: 6435: 6430: 6423: 6411: 6405: 6401: 6397: 6393: 6389: 6382: 6374: 6368: 6359: 6358: 6353: 6350: 6343: 6335: 6329: 6324: 6323: 6317: 6311: 6304: 6299: 6292: 6287: 6280: 6275: 6268: 6263: 6256: 6251: 6235: 6230: 6226: 6222: 6218: 6211: 6204: 6199: 6190: 6189: 6184: 6181: 6174: 6172: 6170: 6161: 6155: 6151: 6144: 6142: 6126: 6122: 6116: 6109: 6104: 6097: 6092: 6085: 6080: 6078: 6076: 6067: 6066: 6060: 6055: 6049: 6047: 6045: 6043: 6041: 6039: 6031: 6026: 6024: 6017:, on Perseus. 6016: 6012: 6007: 6003: 5987: 5980: 5974: 5962: 5958: 5942: 5939: 5937: 5934: 5932: 5929: 5927: 5924: 5922: 5919: 5916: 5912: 5910: 5909:Spherical cow 5907: 5905: 5902: 5900: 5897: 5895: 5892: 5890: 5887: 5885: 5882: 5880: 5877: 5875: 5872: 5870: 5869:Lenart Sphere 5867: 5865: 5862: 5860: 5857: 5855: 5852: 5850: 5847: 5844: 5840: 5837: 5835: 5832: 5830: 5827: 5825: 5822: 5820: 5817: 5815: 5812: 5810: 5807: 5805: 5804:Affine sphere 5802: 5800: 5797: 5796: 5786: 5783: 5781: 5778: 5776: 5773: 5771: 5768: 5766: 5763: 5761: 5758: 5756: 5755:Spherical cap 5753: 5750: 5749: 5746: 5732: 5725: 5720: 5716: 5708: 5700: 5696: 5693: 5689: 5686:the image of 5685: 5678: 5673: 5672: 5666: 5664: 5660: 5655: 5653: 5649: 5645: 5644: 5639: 5635: 5630: 5629: 5618: 5616: 5612: 5608: 5604: 5599: 5597: 5592: 5586: 5580: 5575: 5570: 5565: 5560: 5558: 5554: 5545: 5542: 5538: 5534: 5530: 5519: 5508: 5504: 5499: 5493: 5486:Metric spaces 5483: 5481: 5476: 5468: 5460: 5458: 5457:exotic sphere 5454: 5453:diffeomorphic 5450: 5446: 5442: 5439: 5431: 5426: 5416: 5406: 5404: 5398: 5389: 5381: 5377: 5370: 5366: 5364: 5360: 5352: 5348: 5345: 5339: 5329: 5325: 5324: 5323: 5311: 5302: 5297: 5287: 5283: 5277: 5267: 5265: 5261: 5257: 5242: 5240: 5221: 5215: 5212: 5207: 5203: 5199: 5194: 5190: 5186: 5181: 5171: 5167: 5163: 5160: 5150: 5136: 5133: 5128: 5124: 5120: 5115: 5111: 5107: 5102: 5098: 5094: 5089: 5085: 5077: 5076: 5075: 5060: 5057: 5052: 5048: 5043: 5038: 5034: 5030: 5025: 5021: 5017: 5012: 5002: 4998: 4994: 4991: 4964: 4960: 4956: 4951: 4947: 4943: 4938: 4934: 4930: 4925: 4921: 4909: 4901: 4898: 4897: 4896: 4889: 4880: 4875:is a constant 4874: 4870: 4866: 4863: 4859: 4856: 4855: 4854: 4852: 4848: 4844: 4843:conic section 4838: 4828: 4826: 4822: 4804: 4801: 4798: 4788: 4784: 4766: 4763: 4760: 4757: 4735: 4727: 4711: 4704:(or azimuth) 4703: 4694: 4688: 4683: 4676:Clelia curves 4673: 4671: 4667: 4663: 4659: 4655: 4651: 4647: 4643: 4639: 4630: 4625: 4615: 4613: 4609: 4604: 4599: 4585: 4577: 4568: 4566: 4562: 4557: 4555: 4551: 4541: 4539: 4535: 4531: 4526: 4520: 4519:normal vector 4516: 4512: 4511:tangent plane 4493: 4490: 4487: 4484: 4480: 4477: 4474: 4471: 4467: 4464: 4461: 4458: 4454: 4447: 4446: 4445: 4443: 4439: 4434: 4428: 4424: 4408: 4405: 4401: 4398: 4394: 4391: 4388: 4383: 4379: 4375: 4372: 4369: 4362: 4353: 4351: 4347: 4342: 4336: 4332: 4322: 4320: 4316: 4312: 4304: 4300: 4297: 4293: 4290: 4289: 4288: 4286: 4285: 4279: 4277: 4273: 4269: 4265: 4261: 4257: 4253: 4249: 4244: 4242: 4238: 4234: 4231:, which is a 4230: 4226: 4222: 4218: 4210: 4206: 4201: 4181: 4177: 4165: 4161: 4156: 4155: 4154: 4151: 4146: 4141: 4137: 4134: 4133: 4132: 4129: 4124: 4120: 4116: 4115: 4114: 4111: 4106: 4102: 4101: 4100: 4097: 4091: 4087: 4083: 4079: 4078: 4077: 4074: 4068: 4065: 4064: 4063: 4060: 4055: 4052: 4048: 4045:, cylinders, 4044: 4040: 4037: 4033: 4030: 4027: 4026:focal surface 4023: 4018: 4017: 4016: 4013: 4008: 4005: 4001: 4000: 3995: 3991: 3987: 3982: 3978: 3977: 3976: 3974: 3969: 3964: 3963:circumference 3960: 3959:Meissner body 3956: 3955: 3954: 3951: 3946: 3945: 3944: 3941: 3936: 3932: 3928: 3924: 3920: 3919: 3918: 3915: 3914: 3913: 3911: 3907: 3903: 3902:David Hilbert 3899: 3889: 3880: 3877: 3850: 3847: 3841: 3838: 3835: 3832: 3829: 3823: 3820: 3817: 3811: 3808: 3805: 3802: 3799: 3793: 3790: 3783: 3782: 3781: 3777: 3773: 3769: 3765: 3758: 3754: 3750: 3746: 3739: 3729: 3727: 3723: 3718: 3715: 3714:radical plane 3711: 3706: 3703: 3701: 3700:non-collinear 3697: 3692: 3690: 3686: 3682: 3678: 3674: 3670: 3666: 3656: 3654: 3628: 3625: 3621: 3616: 3610: 3607: 3603: 3598: 3580: 3579: 3578: 3576: 3571: 3569: 3544: 3539: 3535: 3531: 3528: 3525: 3522: 3519: 3515: 3512: 3508: 3505: 3502: 3497: 3493: 3487: 3482: 3478: 3472: 3469: 3464: 3460: 3456: 3453: 3446: 3445: 3444: 3442: 3437: 3433: 3429: 3424: 3420: 3415: 3394: 3389: 3385: 3381: 3378: 3375: 3372: 3365: 3364: 3363: 3346: 3340: 3334: 3331: 3326: 3322: 3318: 3315: 3308: 3307: 3306: 3277: 3274: 3271: 3264: 3258: 3253: 3248: 3244: 3240: 3235: 3231: 3227: 3222: 3219: 3210: 3209: 3208: 3187: 3184: 3181: 3174: 3168: 3163: 3158: 3154: 3150: 3147: 3140: 3139: 3138: 3117: 3114: 3111: 3108: 3102: 3096: 3093: 3090: 3087: 3080: 3079: 3078: 3061: 3058: 3055: 3052: 3046: 3040: 3037: 3034: 3031: 3024: 3023: 3022: 3014: 3010: 2992: 2991: 2985: 2984: 2980: 2958: 2954: 2953:circumscribed 2950: 2932: 2927: 2923: 2919: 2916: 2913: 2910: 2903: 2902: 2901: 2895: 2885: 2856: 2835: 2830: 2806: 2801: 2797: 2793: 2788: 2785: 2780: 2773: 2770: 2766: 2759: 2755: 2751: 2745: 2740: 2736: 2732: 2729: 2726: 2723: 2720: 2715: 2712: 2708: 2704: 2701: 2698: 2692: 2688: 2684: 2678: 2673: 2669: 2663: 2658: 2654: 2650: 2647: 2644: 2641: 2638: 2634: 2631: 2626: 2623: 2619: 2615: 2612: 2609: 2603: 2599: 2595: 2589: 2584: 2580: 2574: 2569: 2565: 2559: 2556: 2551: 2547: 2543: 2540: 2533: 2532: 2531: 2514: 2511: 2507: 2504: 2500: 2497: 2493: 2490: 2487: 2482: 2478: 2474: 2471: 2468: 2461: 2460: 2459: 2458: 2454: 2435: 2430: 2426: 2422: 2417: 2414: 2409: 2405: 2399: 2394: 2390: 2384: 2379: 2375: 2371: 2367: 2363: 2360: 2356: 2350: 2345: 2341: 2335: 2330: 2326: 2321: 2317: 2314: 2309: 2304: 2301: 2296: 2290: 2285: 2281: 2275: 2272: 2267: 2263: 2258: 2253: 2250: 2247: 2240: 2239: 2238: 2221: 2218: 2215: 2211: 2205: 2201: 2197: 2192: 2188: 2183: 2179: 2174: 2169: 2166: 2162: 2158: 2155: 2148: 2147: 2146: 2129: 2124: 2120: 2116: 2111: 2107: 2103: 2098: 2094: 2086: 2085: 2084: 2082: 2063:At any given 2047: 2044: 2041: 2036: 2032: 2028: 2023: 2018: 2015: 2011: 2007: 2004: 1997: 1996: 1995: 1974: 1971: 1968: 1965: 1960: 1956: 1952: 1949: 1946: 1943: 1936: 1935: 1934: 1917: 1914: 1911: 1908: 1903: 1899: 1895: 1892: 1889: 1886: 1879: 1878: 1877: 1867: 1856:At any given 1854: 1853: 1847: 1846: 1842: 1835: 1831: 1825: 1821: 1812: 1808: 1804: 1800: 1796: 1791: 1788: 1787:circumscribed 1784: 1755: 1751: 1747: 1744: 1741: 1736: 1732: 1723: 1720: 1715: 1710: 1706: 1702: 1697: 1694: 1689: 1686: 1679: 1678: 1677: 1675: 1671: 1662: 1648: 1630: 1610: 1586: 1583: 1580: 1577: 1574: 1569: 1565: 1561: 1559: 1554: 1547: 1544: 1541: 1537: 1534: 1531: 1528: 1525: 1520: 1516: 1512: 1510: 1505: 1498: 1495: 1492: 1488: 1485: 1482: 1479: 1476: 1471: 1467: 1463: 1461: 1456: 1445: 1444: 1443: 1441: 1420: 1416: 1412: 1407: 1403: 1399: 1394: 1390: 1366: 1363: 1360: 1352: 1342: 1340: 1334: 1330: 1326: 1322: 1312: 1296: 1272: 1268: 1247: 1244: 1238: 1235: 1232: 1229: 1226: 1220: 1200: 1197: 1194: 1186: 1165: 1161: 1157: 1152: 1148: 1144: 1139: 1135: 1128: 1123: 1119: 1111:is the point 1098: 1095: 1089: 1086: 1083: 1080: 1077: 1071: 1051: 1048: 1045: 1037: 1021: 1018: 1015: 992: 989: 986: 983: 977: 974: 971: 968: 965: 962: 959: 956: 950: 947: 939: 935: 931: 926: 922: 918: 913: 909: 902: 899: 893: 890: 887: 884: 881: 875: 868: 867: 866: 849: 842: 838: 833: 830: 827: 822: 818: 814: 809: 805: 801: 796: 792: 785: 782: 778: 773: 769: 766: 760: 755: 751: 746: 741: 737: 734: 728: 723: 719: 714: 709: 705: 702: 696: 691: 687: 679: 678: 677: 673: 667:a, b, c, d, e 663: 661: 657: 638: 633: 629: 625: 620: 610: 606: 602: 599: 593: 588: 578: 574: 570: 567: 561: 556: 546: 542: 538: 535: 525: 524: 523: 519: 515: 511: 505: 492: 485: 478: 472: 462: 460: 455: 453: 449: 445: 441: 437: 433: 429: 425: 421: 417: 416: 411: 407: 403: 400: 395: 393: 389: 385: 384: 379: 375: 374: 369: 365: 361: 357: 353: 352: 347: 344:Although the 342: 340: 339: 334: 333: 327: 325: 319: 314: 309: 307: 302: 298: 292: 287: 282: 279: 269: 260: 258: 257:ball bearings 254: 250: 246: 242: 238: 234: 230: 226: 222: 218: 214: 210: 205: 203: 199: 194: 189: 185: 180: 175: 174:set of points 171: 167: 163: 158: 152: 148: 144: 117: 115: 111: 105: 103: 99: 96: 91: 89: 85: 81: 79: 75: 72: 68: 65: 61: 56: 50: 45: 40: 37: 33: 19: 6737:Möbius strip 6685:Klein bottle 6637: 6560:. Retrieved 6556: 6542: 6532: 6507: 6472: 6451: 6429: 6420: 6413:. Retrieved 6391: 6381: 6367: 6355: 6342: 6321: 6310: 6298: 6286: 6274: 6262: 6250: 6238:. Retrieved 6224: 6220: 6210: 6198: 6186: 6149: 6128:. Retrieved 6124: 6115: 6103: 6091: 6063: 6014: 6006: 5986: 5978: 5973: 5961: 5884:Pseudosphere 5879:Orb (optics) 5829:Dyson sphere 5692:fused quartz 5659:Dionysodorus 5656: 5641: 5626: 5624: 5600: 5590: 5584: 5578: 5568: 5561: 5546: 5540: 5536: 5532: 5528: 5517: 5506: 5502: 5498:metric space 5495: 5492:Metric space 5474: 5466: 5461: 5427: 5414: 5407: 5403:hyperspheres 5396: 5394:Spheres for 5393: 5379: 5368: 5362: 5350: 5343: 5337: 5327: 5309: 5300: 5292: 5279: 5253: 5236: 4911: 4894: 4878: 4840: 4821:ground track 4699: 4692: 4645: 4641: 4635: 4611: 4605: 4601: 4558: 4547: 4527: 4508: 4435: 4361:area element 4354: 4340: 4328: 4308: 4302: 4283: 4280: 4268:trigonometry 4245: 4241:great circle 4233:great circle 4214: 4209:Great circle 4160:Euler angles 4152: 4145:pseudosphere 4130: 4112: 4098: 4086:soap bubbles 4075: 4061: 4022:focal points 4021: 4014: 3997: 3989: 3985: 3970: 3952: 3942: 3916: 3897: 3895: 3875: 3865: 3775: 3771: 3767: 3763: 3756: 3752: 3748: 3744: 3741: 3719: 3713: 3707: 3704: 3693: 3662: 3646: 3572: 3564: 3435: 3431: 3427: 3419:area element 3416: 3409: 3361: 3292: 3202: 3132: 3076: 3012: 3008: 2993: 2947: 2894:surface area 2891: 2888:Surface area 2854: 2833: 2826: 2529: 2450: 2236: 2144: 2062: 1989: 1932: 1855: 1833: 1829: 1823: 1819: 1772: 1667: 1606: 1348: 1332: 1328: 1324: 1320: 1313: 1185:point sphere 1184: 1035: 1007: 864: 671: 664: 658:, a type of 653: 517: 513: 509: 490: 483: 476: 468: 456: 454:is similar. 439: 435: 427: 423: 413: 409: 396: 391: 382: 371: 367: 363: 359: 349: 343: 337: 336: 332:great circle 330: 328: 317: 310: 300: 296: 290: 283: 277: 274: 217:soap bubbles 206: 192: 178: 156: 142: 140: 102:Surface area 36: 6780:Compactness 6373:"Loxodrome" 6303:Albert 2016 6279:Albert 2016 6267:Albert 2016 6255:Albert 2016 6240:14 December 6227:(6): 1187. 6030:Albert 2016 5941:Zoll sphere 5894:Solid angle 5843:M.C. Escher 5594:squares of 5557:unit sphere 5515:and radius 4825:polar orbit 4211:on a sphere 3441:integration 3203:Substitute 1817:-axis from 1379:and center 498:and radius 428:closed ball 338:hemispheres 313:unit sphere 209:mathematics 162:geometrical 78:Euler char. 57:of a sphere 6877:Categories 6831:Operations 6813:components 6809:Number of 6789:smoothness 6768:Properties 6716:Semisphere 6631:Orientable 6562:21 January 6415:4 November 6291:Woods 1961 6084:Woods 1961 5998:References 5926:Sphericity 5751:Hemisphere 5743:See also: 5707:Australian 5638:Archimedes 5603:octahedron 5551:, as in a 5526:such that 5361:of radius 5284:. For any 5282:dimensions 5250:Ellipsoids 4726:colatitude 4646:rhumb line 4638:navigation 4624:Rhumb line 4515:orthogonal 4252:postulates 4237:arc length 3726:orthogonal 3685:major axis 2957:derivative 2949:Archimedes 1783:Archimedes 1651:Properties 1345:Parametric 522:such that 368:south pole 364:north pole 227:, and the 6858:Immersion 6853:cross-cap 6851:Gluing a 6845:Gluing a 6742:Cross-cap 6687:(genus 2) 6671:genus 1; 6646:(genus 1) 6640:(genus 0) 6454:, Dover, 6357:MathWorld 6293:, p. 267. 6205:, p. 221. 6188:MathWorld 6110:, p. 223. 6086:, p. 266. 5834:Gauss map 5819:Curvature 5733:: Spheres 5695:gyroscope 5652:Zenodorus 5562:Unlike a 5256:ellipsoid 5200:− 5164:− 5121:− 5058:≠ 4995:− 4767:θ 4758:φ 4736:θ 4712:φ 4702:longitude 4662:parallels 4658:meridians 4642:loxodrome 4632:Loxodrome 4618:Loxodrome 4409:φ 4402:θ 4395:θ 4392:⁡ 4317:makes up 4180:helicoids 4070:property. 4067:Geodesics 3669:diameters 3629:ρ 3611:ρ 3532:π 3523:φ 3516:θ 3509:θ 3506:⁡ 3488:π 3479:∫ 3473:π 3461:∫ 3382:π 3319:π 3245:∫ 3228:π 3155:∫ 3112:δ 3109:⋅ 3094:∑ 3091:≈ 3056:δ 3053:⋅ 3038:≈ 3032:δ 2920:π 2829:inscribed 2794:π 2737:∫ 2733:π 2724:θ 2705:θ 2702:⁡ 2670:∫ 2664:π 2655:∫ 2651:π 2642:φ 2635:θ 2616:θ 2613:⁡ 2581:∫ 2575:π 2566:∫ 2560:π 2548:∫ 2515:φ 2508:θ 2494:θ 2491:⁡ 2423:π 2372:− 2364:π 2361:− 2336:− 2318:π 2302:− 2276:− 2254:π 2198:− 2180:π 2167:− 2163:∫ 2117:− 2029:π 2016:− 2012:∫ 1969:δ 1966:⋅ 1953:π 1950:∑ 1947:≈ 1912:δ 1909:⋅ 1896:π 1893:≈ 1887:δ 1748:⋅ 1742:≈ 1721:π 1703:π 1631:φ 1587:θ 1584:⁡ 1548:φ 1545:⁡ 1538:θ 1535:⁡ 1499:φ 1496:⁡ 1489:θ 1486:⁡ 1297:ρ 1195:ρ 1046:ρ 1016:ρ 828:− 783:ρ 767:− 735:− 703:− 603:− 571:− 539:− 465:Equations 450:" in the 424:open ball 392:parallels 383:meridians 378:longitude 239:and most 233:astronomy 225:geography 18:Spherical 6918:Topology 6913:Surfaces 6811:boundary 6730:Cylinder 6305:, p. 58. 6281:, p. 57. 6269:, p. 55. 6257:, p. 60. 6183:"Sphere" 6032:, p. 54. 5799:3-sphere 5792:See also 5697:for the 5688:Einstein 5684:refracts 5609:, and a 5596:integers 5470:‖ 5464:‖ 5445:boundary 5443:without 5430:topology 5388:3-sphere 5296:-sphere, 5276:n-sphere 4724:and the 4544:Topology 4229:geodesic 4140:embedded 4119:embedded 4051:cyclides 3973:umbilics 3929:for the 3696:coplanar 3689:spheroid 2858:, where 2774:′ 2756:′ 2716:′ 2689:′ 2627:′ 2600:′ 2083:yields: 1811:circular 1790:cylinder 676:and put 432:boundary 402:embedded 286:diameter 215:such as 6908:Spheres 6761:notions 6759:Related 6725:Annulus 6721:Ribbon 6545:, Dover 6483:Bibcode 6481:, 226. 6130:10 June 5739:Regions 5669:Gallery 5663:al-Quhi 5646:by the 5621:History 5438:compact 5418:‍ 5383:‍ 5372:‍ 5354:‍ 5331:‍ 5304:‍ 5264:ellipse 4899:Example 4851:quartic 4817:⁠ 4791:⁠ 4779:⁠ 4750:⁠ 4650:bearing 4612:coaxial 4592:Circles 4276:similar 4093:bodies. 3677:ellipse 3653:density 3651:is the 3436:θ dθ dφ 3297:yields 2878:⁠ 2864:⁠ 2852:⁠ 2838:⁠ 2455:, with 1801:(i.e., 502:is the 446:" and " 373:equator 213:Bubbles 160:) is a 157:sphaîra 132:⁠ 120:⁠ 6847:handle 6638:Sphere 6520:  6493:  6458:  6406:  6330:  6156:  6011:σφαῖρα 5711:  5703:  5553:normed 5520:> 0 5449:smooth 5432:, the 5399:> 2 5359:circle 5219:  4682:Clélie 4532:, the 4264:angles 4221:points 4170:- and 4041:* For 4034:* For 3931:circle 3923:result 3665:circle 3647:where 3410:where 2882:  2778:  1773:where 1745:0.5236 1729:  1670:volume 444:circle 440:sphere 412:and a 410:sphere 245:lenses 198:radius 188:center 170:circle 151:σφαῖρα 145:(from 143:sphere 114:Volume 42:Sphere 6817:Genus 6644:Torus 6514:Wiley 5953:Notes 5572:with 5291:, an 5237:(see 4429:with 4298:, and 4258:. In 4225:lines 4043:cones 3935:plane 3910:plane 3778:) = 0 3759:) = 0 1335:) = 0 1038:. If 504:locus 452:plane 360:poles 253:balls 147:Greek 6712:Disk 6564:2022 6518:ISBN 6491:ISBN 6456:ISBN 6417:2022 6404:ISBN 6328:ISBN 6242:2019 6154:ISBN 6132:2019 5611:cube 5564:ball 5539:) = 5408:The 5386:: a 5341:and 4873:foci 4849:, a 4640:, a 4359:has 4223:and 4219:are 4178:and 4103:The 4049:and 4047:tori 3904:and 3870:and 3761:and 3434:sin 2900:is: 2892:The 2075:and 1674:ball 1623:and 1364:> 1198:> 1019:< 665:Let 448:disk 438:and 436:ball 415:ball 390:(or 366:and 351:axis 249:roll 243:and 94:O(3) 63:Type 6787:or 6751:... 6396:doi 6229:doi 5640:'s 5601:An 5459:). 5428:In 5312:+ 1 5254:An 4695:= 8 4644:or 4636:In 4528:In 4523:1/r 4425:in 4389:sin 4296:arc 3925:of 3742:If 3503:sin 3425:by 3021:): 2699:sin 2610:sin 2530:so 2488:sin 1876:): 1868:at 1827:to 1822:= − 1809:of 1581:cos 1542:sin 1532:sin 1493:cos 1483:sin 1314:If 674:≠ 0 469:In 461:). 380:or 320:= 1 299:= 2 223:in 107:4πr 6879:: 6555:. 6516:, 6489:. 6479:28 6419:. 6402:. 6394:. 6390:. 6354:. 6225:84 6223:. 6219:. 6185:. 6168:^ 6140:^ 6123:. 6074:^ 6062:. 6037:^ 6022:^ 5841:, 5665:. 5650:. 5617:. 5598:. 5559:. 5544:. 5482:. 5405:. 4827:. 4785:. 4672:. 4556:. 4540:. 4525:. 4494:0. 4444:: 4339:1/ 4321:. 4262:, 3900:, 3774:, 3770:, 3755:, 3751:, 3443:: 3430:= 3428:dA 3305:: 3207:: 3135:δr 3019:δr 3000:δV 2836:= 2071:, 1992:δx 1874:δx 1862:δV 1832:= 1647:. 1611:. 1442:. 1349:A 1341:. 1331:, 1327:, 1311:. 1213:, 662:. 516:, 512:, 489:, 482:, 341:. 329:A 311:A 259:. 204:. 154:, 141:A 134:πr 53:A 6611:e 6604:t 6597:v 6566:. 6547:. 6537:. 6527:. 6499:. 6485:: 6465:. 6436:. 6398:: 6375:. 6360:. 6336:. 6244:. 6231:: 6191:. 6162:. 6134:. 5981:. 5979:π 5966:r 5717:. 5591:n 5585:r 5579:r 5569:Z 5549:E 5541:r 5537:y 5535:, 5533:x 5531:( 5529:d 5524:y 5518:r 5513:x 5509:) 5507:d 5505:, 5503:E 5501:( 5475:S 5467:x 5434:n 5423:n 5415:S 5410:n 5397:n 5380:S 5369:S 5363:r 5351:S 5344:r 5338:r 5336:− 5328:S 5320:r 5316:r 5310:n 5301:S 5294:n 5289:n 5222:. 5216:0 5213:= 5208:2 5204:a 5195:2 5191:z 5187:+ 5182:2 5178:) 5172:0 5168:y 5161:y 5158:( 5137:0 5134:= 5129:2 5125:r 5116:2 5112:z 5108:+ 5103:2 5099:y 5095:+ 5090:2 5086:x 5061:0 5053:0 5049:y 5044:, 5039:2 5035:a 5031:= 5026:2 5022:z 5018:+ 5013:2 5009:) 5003:0 4999:y 4992:y 4989:( 4965:2 4961:r 4957:= 4952:2 4948:z 4944:+ 4939:2 4935:y 4931:+ 4926:2 4922:x 4805:1 4802:= 4799:c 4789:( 4764:c 4761:= 4693:c 4491:= 4488:z 4485:d 4481:z 4478:+ 4475:y 4472:d 4468:y 4465:+ 4462:x 4459:d 4455:x 4431:r 4406:d 4399:d 4384:2 4380:r 4376:= 4373:A 4370:d 4357:r 4341:r 4172:y 4168:x 4028:. 3975:. 3937:. 3872:t 3868:s 3851:0 3848:= 3845:) 3842:z 3839:, 3836:y 3833:, 3830:x 3827:( 3824:g 3821:t 3818:+ 3815:) 3812:z 3809:, 3806:y 3803:, 3800:x 3797:( 3794:f 3791:s 3776:z 3772:y 3768:x 3766:( 3764:g 3757:z 3753:y 3749:x 3747:( 3745:f 3649:ρ 3626:r 3622:3 3617:= 3608:V 3604:A 3599:= 3595:A 3592:S 3589:S 3545:. 3540:2 3536:r 3529:4 3526:= 3520:d 3513:d 3498:2 3494:r 3483:0 3470:2 3465:0 3457:= 3454:A 3432:r 3412:r 3395:, 3390:2 3386:r 3379:4 3376:= 3373:A 3347:. 3344:) 3341:r 3338:( 3335:A 3332:= 3327:2 3323:r 3316:4 3303:r 3299:A 3295:r 3278:. 3275:r 3272:d 3268:) 3265:r 3262:( 3259:A 3254:r 3249:0 3241:= 3236:3 3232:r 3223:3 3220:4 3205:V 3188:. 3185:r 3182:d 3178:) 3175:r 3172:( 3169:A 3164:r 3159:0 3151:= 3148:V 3118:. 3115:r 3106:) 3103:r 3100:( 3097:A 3088:V 3062:. 3059:r 3050:) 3047:r 3044:( 3041:A 3035:V 3015:) 3013:r 3011:( 3009:A 3006:( 3004:r 2996:r 2977:r 2973:r 2969:r 2965:r 2961:r 2933:. 2928:2 2924:r 2917:4 2914:= 2911:A 2898:r 2875:6 2872:/ 2868:π 2860:d 2855:d 2849:6 2846:/ 2842:π 2834:V 2807:. 2802:3 2798:r 2789:3 2786:4 2781:= 2771:r 2767:d 2760:2 2752:r 2746:r 2741:0 2730:4 2727:= 2721:d 2713:r 2709:d 2693:2 2685:r 2679:r 2674:0 2659:0 2648:2 2645:= 2639:d 2632:d 2624:r 2620:d 2604:2 2596:r 2590:r 2585:0 2570:0 2557:2 2552:0 2544:= 2541:V 2512:d 2505:d 2501:r 2498:d 2483:2 2479:r 2475:= 2472:V 2469:d 2436:. 2431:3 2427:r 2418:3 2415:4 2410:= 2406:) 2400:3 2395:3 2391:r 2385:+ 2380:3 2376:r 2368:( 2357:) 2351:3 2346:3 2342:r 2331:3 2327:r 2322:( 2315:= 2310:r 2305:r 2297:] 2291:3 2286:3 2282:x 2273:x 2268:2 2264:r 2259:[ 2251:= 2248:V 2222:, 2219:x 2216:d 2212:) 2206:2 2202:x 2193:2 2189:r 2184:( 2175:r 2170:r 2159:= 2156:V 2130:. 2125:2 2121:x 2112:2 2108:r 2104:= 2099:2 2095:y 2077:r 2073:y 2069:x 2065:x 2048:. 2045:x 2042:d 2037:2 2033:y 2024:r 2019:r 2008:= 2005:V 1975:. 1972:x 1961:2 1957:y 1944:V 1918:. 1915:x 1904:2 1900:y 1890:V 1870:x 1858:x 1839:r 1834:r 1830:x 1824:r 1820:x 1815:x 1779:d 1775:r 1756:3 1752:d 1737:3 1733:d 1724:6 1716:= 1711:3 1707:r 1698:3 1695:4 1690:= 1687:V 1645:π 1621:π 1617:θ 1613:r 1578:r 1575:+ 1570:0 1566:z 1562:= 1555:z 1529:r 1526:+ 1521:0 1517:y 1513:= 1506:y 1480:r 1477:+ 1472:0 1468:x 1464:= 1457:x 1426:) 1421:0 1417:z 1413:, 1408:0 1404:y 1400:, 1395:0 1391:x 1387:( 1367:0 1361:r 1333:z 1329:y 1325:x 1323:( 1321:f 1316:a 1273:0 1269:P 1248:0 1245:= 1242:) 1239:z 1236:, 1233:y 1230:, 1227:x 1224:( 1221:f 1201:0 1171:) 1166:0 1162:z 1158:, 1153:0 1149:y 1145:, 1140:0 1136:x 1132:( 1129:= 1124:0 1120:P 1099:0 1096:= 1093:) 1090:z 1087:, 1084:y 1081:, 1078:x 1075:( 1072:f 1052:0 1049:= 1022:0 993:0 990:= 987:e 984:+ 981:) 978:z 975:d 972:+ 969:y 966:c 963:+ 960:x 957:b 954:( 951:2 948:+ 945:) 940:2 936:z 932:+ 927:2 923:y 919:+ 914:2 910:x 906:( 903:a 900:= 897:) 894:z 891:, 888:y 885:, 882:x 879:( 876:f 850:. 843:2 839:a 834:e 831:a 823:2 819:d 815:+ 810:2 806:c 802:+ 797:2 793:b 786:= 779:, 774:a 770:d 761:= 756:0 752:z 747:, 742:a 738:c 729:= 724:0 720:y 715:, 710:a 706:b 697:= 692:0 688:x 672:a 639:. 634:2 630:r 626:= 621:2 617:) 611:0 607:z 600:z 597:( 594:+ 589:2 585:) 579:0 575:y 568:y 565:( 562:+ 557:2 553:) 547:0 543:x 536:x 533:( 520:) 518:z 514:y 510:x 508:( 500:r 496:) 494:0 491:z 487:0 484:y 480:0 477:x 475:( 362:( 318:r 301:r 297:d 291:d 278:r 193:r 179:r 129:3 126:/ 123:4 82:2 34:. 20:)

Index

Spherical
Sphere (disambiguation)

perspective projection
Smooth surface
Algebraic surface
Euler char.
Symmetry group
O(3)
Surface area
Volume
Greek
σφαῖρα
geometrical
three-dimensional
circle
set of points
three-dimensional space
center
radius
ancient Greek mathematicians
mathematics
Bubbles
soap bubbles
often approximated as a sphere
geography
celestial sphere
astronomy
pressure vessels
curved mirrors

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.