cosmological model of concentric (or homocentric) spheres, developed by Eudoxus, Callippus, and Aristotle, employed celestial spheres all centered on the...

circles (any line through the center), spheres, cylinders, conic sections, and surfaces of revolution. Concentric objects are often part of the broad category...

student Eudoxus developed a planetary model using concentric spheres for all the planets, with three spheres each for his models of the Moon and the Sun and...

three concentric spheres: consensus, legitimate controversy, and deviance. In the sphere of consensus, journalists assume everyone agrees. The sphere of...

spheres". Ultimately, Symmes was to simplify his theory, abandoning the series of concentric inner spheres, and teaching "only one concentric sphere (a...

symbolises theology. In the poem, Paradise is depicted as a series of concentric spheres surrounding the Earth, consisting of the Moon, Mercury, Venus, the...

polyhedron are congruent. A convex regular polyhedron has all of three related spheres (other polyhedra lack at least one kind) which share its centre: An insphere...

astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky...

stereographic projection as two concentric spheres, in a similar way that a tesseract (cubic prism) can be projected as two concentric cubes, and how a circular...

structuring of the cosmos into concentric spheres, with the Earth at the centre and celestial spheres around it. The terrestrial sphere was made of four elements...

mathematical astronomy, his fame is due to the introduction of the concentric spheres, and his early contributions to understanding the movement of the...

between two concentric spheres of differing radii. The volume of a spherical shell is the difference between the enclosed volume of the outer sphere and the...

astronomer to present the concentric spheres model as an alternative to the Ptolemaic system, with the planets borne by geocentric spheres. Another original aspect...

two inner concentric shells and an innermost core. Atmospheres separate these shells, and each shell has its own magnetic poles. The spheres rotate at...

based on concentric spheres and quadratic cones is called a conical or sphero-conical coordinate system. When restricted to the surface of a sphere, the remaining...

rotating spheres surrounding the Earth, all concentric with it. (The number is so high because several spheres are needed for each planet.) These spheres, known...

based on (conceptual) concentric spheres centered on Earth, and by 360 BC Plato claimed in his Timaeus that circles and spheres were the preferred shape...

profiles, the lens will form perfect geometrical images of two given concentric spheres onto each other. There are an infinite number of refractive-index...

an unrolled sphere in between, increasing the number of spheres needed well above Eudoxus'. Historians are unsure about how many spheres Aristotle thought...

cosmology or the Greek notion of the surrounding of the Earth by seven concentric spheres: one for the sun, one for the moon, and one for each of the five other...

spicules, but in others it forms more elaborate lattices, such as concentric spheres with radial spines or sequences of conical chambers. Two of the orders...

or Concentric spheres in an attempt to bring it back to the scientific sphere. It was criticised by Christopher Clavius, since Homocentric Spheres could...

(Klerksdorp spheres), and layers at multiple horizons within thin beds of carbonaceous shale or slate, which is locally called wonderstone. Klerksdorp spheres are...

regularity is that the Platonic solids all possess three concentric spheres: the circumscribed sphere that passes through all the vertices, the midsphere that...

series of concentric spheres each including a hierarchical organization of spirits in a setting more earth-like than theocentric. The spheres become gradually...

known objects that allow such a solution: spheres, concentric spheres, infinite cylinders, clusters of spheres and clusters of cylinders. There are also...

forces and viscous forces. For simplicity, consider the example of two concentric spheres that rotate about a common axis with slightly different angular velocity...

is r, then its mean curvature is ⁠n/r⁠. As such, such a family of concentric spheres forms an inverse mean curvature flow if and only if r ′ ( t ) = r...

galaxy. A class-B stellar engine consists of two concentric spheres around a star. The inner sphere (which may be assimilated with a Dyson shell) receives...

including pressure vessels and most curved mirrors and lenses are based on spheres. Spheres roll smoothly in any direction, so most balls used in sports and toys...