What is universe?

Answer 1

university

Answer 2

The Universe is defined as the summation of all particles and energy that exist and the space-time in which all events occur. Based on observations of the portion of the Universe that is observable, physicists attempt to describe the whole of space-time, including all matter and energy and events which occur, as a single system corresponding to a mathematical model.

The generally accepted scientific theory which describes the origin and evolution of the Universe is Big Bang cosmology, which describes the expansion of space from an extremely hot and dense state of unknown characteristics. The Universe underwent a rapid period of cosmic inflation that flattened out nearly all initial irregularities in the energy density; thereafter the universe expanded and became steadily cooler and less dense. Minor variations in the distribution of mass resulted in hierarchical segregation of the features that are found in the current universe; such as clusters and superclusters of galaxies. There are more than one hundred billion (1011) galaxies in the Universe,[1] each containing hundreds of billions of stars, with each star containing about 1057 atoms of hydrogen.

Other ways of exploring and describing the origin and evolution of the universe include religious cosmology and philosophical cosmology.

Answer 3

The Universe is defined as the summation of all particles and energy that exist and the space-time in which all events occur. Based on observations of the portion of the Universe that is observable, physicists attempt to describe the whole of space-time, including all matter and energy and events which occur, as a single system corresponding to a mathematical model.

Answer 4

Universe means all existing things i.e. the whole creation.The three main constituents of universe are (1) solar system (2) stars and (3) galaxies.

Answer 5

Universe=infinity.

Answer 6

All existing matter and space considered as a whole . the cosmos. a particular sphere of activity of experience...
other words ..combined in to one,,whole

Answer 7

Universe is all the Matter i.e., all the solids, liquids and gases and also the anti matter ofcourse...

Answer 8

The Universe is defined as the summation of all particles and energy that exist and the space-time in which all events occur.
Based on observations of the portion of the Universe that is observable, physicists attempt to describe the whole of space-time, including all matter and energy and events which occur, as a single system corresponding to a mathematical model.

The generally accepted scientific theory which describes the origin and evolution of the Universe is Big Bang cosmology, which describes the expansion of space from an extremely hot and dense state of unknown characteristics. The Universe underwent a rapid period of cosmic inflation that flattened out nearly all initial irregularities in the energy density; thereafter the universe expanded and became steadily cooler and less dense. Minor variations in the distribution of mass resulted in hierarchical segregation of the features that are found in the current universe; such as clusters and superclusters of galaxies. There are more than one hundred billion (1011) galaxies in the Universe,[1] each containing hundreds of billions of stars, with each star containing about 1057 atoms of hydrogen.

Name of our Universe

In the same way that the Moon refers to our (Earth's) moon, the Universe is used by some cosmologists to refer to our Universe. In this article, the Universe is equivalent to our observable Universe.

Theoretical and observational cosmologists vary in their usage of the term the Universe to mean either this whole system or just a part of this system.[2]

As used by observational cosmologists, the Universe most frequently refers to the finite part of space-time. The Universe is directly observable by making observations using telescopes and other detectors, and by using the methods of theoretical and empirical physics for studying its components. Physical cosmologists assume that the observable part of (comoving) space (also called our universe) corresponds to a part of a model of the whole of space, and usually not to the whole space. They use the term the Universe ambiguously to mean either the observable part of space, the observable part of space-time, or the entire space-time.[citation needed]

In order to clarify terminology, George Ellis, U. Kirchner and W.R. Stoeger recommend using the term the Universe for the theoretical model of all of the connected space-time in which we live, universe domain for the observable universe or a similar part of the same space-time, universe for a general space-time (either our own Universe or another one disconnected from our own), multiverse for a set of disconnected space-times, and multi-domain universe to refer to a model of the whole of a single connected space-time in the sense of chaotic inflation models

Formation

Main articles: Age of the universe and Big Bang

The most important result of physical cosmology—that the universe is expanding—is derived from redshift observations and quantified by Hubble's Law. That is, astronomers observe that there is a direct relationship between the distance to a remote object (such as a galaxy) and the velocity with which it is receding. Conversely, if this expansion has continued over the entire age of the universe, then in the past, these distant, receding objects must once have been closer together.

By extrapolating this expansion back in time, one approaches a gravitational singularity where everything in the universe was compressed into an infinitesimal point; an abstract mathematical concept that may or may not correspond to reality. This idea gave rise to the Big Bang Theory, the dominant model in cosmology today.

During the earliest era of the big bang theory, the universe is believed to have formed a hot, dense plasma. As expansion proceeded, the temperature steadily dropped until a point was reached when atoms could form. At about this time the background energy (in the form of photons) became decoupled from the matter, and was free to travel through space. The left-over energy continued to cool as the universe expanded, and today it forms the cosmic microwave background radiation. This background radiation is remarkably uniform in all directions, which cosmologists have attempted to explain by an early period of inflationary expansion following the Big Bang.

Examination of small variations in the microwave background radiation provides information about the nature of the universe, including the age and composition. The age of the universe from the time of the Big Bang, according to current information provided by NASA's WMAP (Wilkinson Microwave Anisotropy Probe), is estimated to be about 13.7 billion (13.7 × 109) years, with a margin of error of about 1 % (± 200 million years). Other methods of estimation give different ages ranging from 11 billion to 20 billion.[6] Most of the estimates cluster in the 13–15 billion year range.[7][8]

In the 1977 book The First Three Minutes, Nobel Prize-winner Steven Weinberg laid out the physics of what happened just moments after the Big Bang. Additional discoveries and refinements of theories prompted him to update and reissue that book in 1993.



Other ways of exploring and describing the origin and evolution of the universe include religious cosmology and philosophical cosmology.
Etymology

The word "universe" is derived from Old French univers, from Latin universum, which combines uni- (the combining form of unus, or "one") with versus (perfect passive participle of vertere, or "turn"). The word, therefore, means "all turned into one" or "revolving as one" or "orbiting as one".

Answer 9

Everything inside the earth and outside of it

Answer 10

all of it

all the galaxies and empty space

everything