closed universe Geometry that the universe as a whole would have if the density of matter is above the critical value. A closed universe is finite in extent, and has no edge, like the surface of a sphere.
Closed universe
If Ω1, then the geometry of space is closed like the surface of a sphere. The sum of the angles of a triangle exceeds 180 degrees and there are no parallel lines; all lines eventually meet.
Closed Universe
A model universe in which the average density is great enough to stop the expansion and make the universe contract.
Cluster Method ...
Closed Universe
(a) Any model of the Universe in which the gravity of the matter content can reverse the expansion and cause a collapse.
(b) A standard universe with a spherical three-dimensional spatial geometry.
CLOSED UNIVERSE
A closed universe is a model of the universe in which the universe first expands (after the big bang), and then contracts, due to the gravitational forces of the matter in the universe.
Closed Universe
A geometric model of the universe in which the overall structure of the universe closes upon itself like the surface of a sphere. The rules of geometry in a closed universe are like those that would apply on the surface of a sphere.
Closed Universe: A model of the universe that has spherical geometry (hence is finite in space) and which will eventually stop expanding and recollapse (and hence is finite in time as well).
closed universe - (n.)
A possible state of the universe. In this state, the expansion of the universe will eventually be reversed; it is characterized by positive curvature, being finite in extent but having no boundaries.
A Closed Universe
Click on image for full size
STScI
If there is enough matter in the Universe eventually gravitational forces will stop its expansion.
The closed universe is similar to the surface of a sphere, the size is finite but there is no boundary. The size of an open universe is infinite and its geometry will be similar to a hyperbolic surface.
Will a closed universe violate the 2nd law of thermodynamics?
Will entropy increase with time as the Universe evolves?
Could we compare the early Universe to a black hole?
closed universe a universe with enough matter (gravity) to eventually stop the expansion and recollapse (it has a "closed future"). color-magnitude diagram a plot of the colors (temperatures) and magnitudes of stars.
Closed universes expand for a finite time, reach a maximum size, and then collapse.
Such a universe is known as a closed universe. It is difficult to visualize a three-dimensional volume uniformly arching back on itself in this way, but the two-dimensional version is well known: it is just the surface of a sphere, ...
In the case of a closed Universe, not only would the expansion be stopped but also eventually reversed. The Universe will start heading toward a collapse after the expansion is stopped.
If the density of matter in the Universe is high (a closed Universe), self-gravity slows the expansion until it halts, and ultimately re-collapses. In a closed Universe, locally parallel light rays converge at some extremely distant point.
If one speaks in Newtonian terms, the cosmological constant could be interpreted as a repulsive force of unknown origin that could exactly balance the attraction of gravitation of all the matter in Einstein's closed universe and keep it from moving.
This corresponds to a closed universe: gravity wins. But if you were strong enough you could send the ball into space and it would never come back to Earth. This corresponds to an open universe: the initial force wins.
A closed Universe would cause parallel rays of light to converge, magnifying the spots. Conversely an open Universe would cause the rays of light to diverge, making the spots appear smaller. Results from BOOMERANG indicate that the Universe is flat.
Its also part of the self-reflesivity-- not only is Joyce parodying himself, but he is parodying his own characters and his own influences. This is part of what Umberto Eco describes as a 'closed universe': ...
The expansion will eventually stop and turn into a contraction. Thus, at some point in the future the galaxies will stop receding from each other and begin approaching each other as the Universe collapses on itself. This is called a closed Universe.
 See also: Universe, Density, Time, Mass, Model
|
