id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
en-wikipedia-org-191		Physical object - Wikipedia			.html	text/html	2036	250	61	In common usage, a physical object or physical body (or simply an object or body) is a collection of matter within a defined contiguous boundary in three-dimensional space.[citation needed] The boundary must be defined and identified by the properties of the material. In physics, an object is an identifiable collection of matter, which may be constrained by an identifiable boundary, and may move as a unit by translation or rotation, in 3-dimensional space. The common conception of physical objects includes that they have extension in the physical world, although there do exist theories of quantum physics and cosmology which may challenge[how?] this. For a rigid body, the boundary of an object may change over time by continuous translation and rotation. In some philosophies, like the idealism of George Berkeley, a physical body is a mental object, but still has extension in the space of a visual field.	./cache/en-wikipedia-org-191.html	./txt/en-wikipedia-org-191.txt