Top

A top is a toy designed to be spun rapidly on the ground, the motion of which causes it to remain precisely balanced on its tip because of inertia. Such toys have existed since antiquity. Traditionally tops were constructed of wood, sometimes with an iron tip, and would be set in motion by aid of a string or rope coiled around its axis which, when pulled quickly, caused a rapid unwinding that would set the top in motion. Today they are often built of plastic, and modern materials and manufacturing processes allow tops to be constructed with such precise balance that they can be set in motion by a simple twist of the fingers and twirl of the wrist without need for string or rope.

Characteristics

The motion of a top is produced in the most simple forms by twirling the stem using the fingers. More sophisticated tops are spun by holding the axis firmly while pulling a string or twisting a stick or pushing an auger. In the kinds with an auger, an internal weight rotates, producing an overall circular motion. Some tops can be thrown, while firmly grasping a string that had been tightly wound around the stem, and the centrifugal force generated by the unwinding motion of the string will set them spinning upon touching ground.

Top (mathematics)

In the context of a module M over a ring R, the top of M is the largest semisimple quotient module of M if it exists.

For finite-dimensional k-algebras (k a field), if rad(M) denotes the intersection of all proper maximal submodules of M (the radical of the module), then the top of M is M/rad(M). In the case of local rings with maximal ideal P, the top of M is M/PM. In general if R is a semilocal ring (=semi-artinian ring), that is, if R/Rad(R) is an Artinian ring, where Rad(R) is the Jacobson radical of R, then M/rad(M) is a semisimple module and is the top of M. This includes the cases of local rings and finite dimensional algebras over fields.

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Top (clothing)

A top is clothing that covers at least the chest, but which usually covers most of the upper human body between the neck and the waistline. The bottom of tops can be as short as mid-torso, or as long as mid-thigh. Men's tops are generally paired with pants, and women's with pants or skirts. Common types of tops are t-shirts, blouses and shirts.

Design

The neckline is the highest line of the top, and may be as high as a head-covering hood, or as low as the waistline or bottom hem of the top. A top may be worn loose or tight around the bust or waist, and may have sleeves or shoulder straps, spaghetti straps (noodle straps), or may be strapless. The back may be covered or bare. Tops may have straps around the waist or neck, or over the shoulders.

Types

Neck styles

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Maze

A maze is a path or collection of paths, typically from an entrance to a goal. The word is used to refer both to branching tour puzzles through which the solver must find a route, and to simpler non-branching ("unicursal") patterns that lead unambiguously through a convoluted layout to a goal. (The term "labyrinth" is generally synonymous, but also can connote specifically a unicursal pattern.) The pathways and walls in a maze are typically fixed, but puzzles in which the walls and paths can change during the game are also categorised as mazes or tour puzzles.

Maze construction

Mazes have been built with walls and rooms, with hedges, turf, corn stalks, hay bales, books, paving stones of contrasting colors or designs, and brick, or in fields of crops such as corn or, indeed, maize. Maize mazes can be very large; they are usually only kept for one growing season, so they can be different every year, and are promoted as seasonal tourist attractions. Indoors, Mirror Mazes are another form of maze, in which many of the apparent pathways are imaginary routes seen through multiple reflections in mirrors. Another type of maze consists of a set of rooms linked by doors (so a passageway is just another room in this definition). Players enter at one spot, and exit at another, or the idea may be to reach a certain spot in the maze. Mazes can also be printed or drawn on paper to be followed by a pencil or fingertip.

MAZE: Solve the World's Most Challenging Puzzle

MAZE: Solve the World's Most Challenging Puzzle (1985, Henry Holt and Company) is a puzzle book written and illustrated by Christopher Manson. The book was originally published as part of a contest to win $10,000.

Unlike other puzzle books, each page is involved in solving the book's riddle. Specifically, each page represents a room or space in a hypothetical house, and each room leads to other "rooms" in this "house." Part of the puzzle involves reaching the center of the house, Room #45 (which is page 45 in the book), and back to Room #1 in only sixteen steps. Some rooms lead to circuitous loops; others lead nowhere. This gives the puzzle the feel of a maze or labyrinth.

The book was adapted as the computer game Riddle of the Maze in 1994 by Interplay. This version featured full color illustrations and voice-overs for the narrator.

The contest has been void since 1987, but the book may still be purchased (ISBN 0-8050-1088-2).

Parts of the Puzzle