NOTE : The information below should NOT have to be Posted on a Science Forum !!!
For some reason, some people seem to equate Theory with Fact - and seem to believe/assume a Theory is indeed a Fact.
The Big Bang Theory is the currently accepted working Hypothesis/Model to explain one possible/probable origin of the known observable universe - possible/probable yes, but yet to be conclusively Proven as actual Fact.
In all honesty - the origin of the known observable universe will, MOST LIKELY, never be conclusively, beyond any/all shadow of doubt, Proven.
Scientists may/will Theorize - Religions may/will claim - Philosophers may/will ponder - Dreamers may/will visualize/fantasize - Cranks/Crackpots may/will continue to...spew - Authors may/will fictionalize - and the Ignorant may/will remain uninterested - but the actual truth of origin may well never be known.
All that being said, below are some definitions that Scientist (are required/expected to) know.
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- below from :
http://dictionary.reference.com/browse/theory -
the·o·ry [thee-uh-ree, theer-ee] Show IPA
noun, plural the·o·ries.
1. a coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena: Einstein's theory of relativity. Synonyms: principle, law, doctrine.
2. a proposed explanation whose status is still conjectural and subject to experimentation, in contrast to well-established propositions that are regarded as reporting matters of actual fact. Synonyms: idea, notion hypothesis, postulate. Antonyms: practice, verification, corroboration, substantiation.
3. Mathematics . a body of principles, theorems, or the like, belonging to one subject: number theory.
4. the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.
5. a particular conception or view of something to be done or of the method of doing it; a system of rules or principles: conflicting theories of how children best learn to read.
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- below from :
http://www.merriam-webster.com/dictionary/theory
the·o·ry noun \ˈthē-ə-rē, ˈthir-ē\
: an idea or set of ideas that is intended to explain facts or events
: an idea that is suggested or presented as possibly true but that is not known or proven to be true
: the general principles or ideas that relate to a particular subject
Full Definition of THEORY
1: the analysis of a set of facts in their relation to one another
2: abstract thought : speculation
3: the general or abstract principles of a body of fact, a science, or an art <music theory>
4a : a belief, policy, or procedure proposed or followed as the basis of action <her method is based on the theory that all children want to learn>
4b : an ideal or hypothetical set of facts, principles, or circumstances —often used in the phrase in theory <in theory, we have always advocated freedom for all>
5: a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena <the wave theory of light>
6a : a hypothesis assumed for the sake of argument or investigation
6b : an unproved assumption : conjecture
6c : a body of theorems presenting a concise systematic view of a subject <theory of equations>
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- below from :
http://www.merriam-webster.com/dictionary/theory
Definition of BIG BANG THEORY
: a theory in astronomy: the universe originated billions of years ago in an explosion from a single point of nearly infinite energy density
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- below from :
http://science.nationalgeographic.com/science/space/universe/origins-universe-article/
The most popular theory of our universe's origin centers on a cosmic cataclysm unmatched in all of history—the big bang. This theory was born of the observation that other galaxies are moving away from our own at great speed, in all directions, as if they had all been propelled by an ancient explosive force.
Before the big bang, scientists believe, the entire vastness of the observable universe, including all of its matter and radiation, was compressed into a hot, dense mass just a few millimeters across. This nearly incomprehensible state is theorized to have existed for just a fraction of the first second of time.
Big bang proponents suggest that some 10 billion to 20 billion years ago, a massive blast allowed all the universe's known matter and energy—even space and time themselves—to spring from some ancient and unknown type of energy.
Origins of the Theory
A Belgian priest named Georges Lemaître first suggested the big bang theory in the 1920s when he theorized that the universe began from a single primordial atom. The idea subsequently received major boosts by Edwin Hubble's observations that galaxies are speeding away from us in all directions, and from the discovery of cosmic microwave radiation by Arno Penzias and Robert Wilson.
The glow of cosmic microwave background radiation, which is found throughout the universe, is thought to be a tangible remnant of leftover light from the big bang. The radiation is akin to that used to transmit TV signals via antennas. But it is the oldest radiation known and may hold many secrets about the universe's earliest moments.
The big bang theory leaves several major questions unanswered. One is the original cause of the big bang itself. Several answers have been proposed to address this fundamental question, but none has been proven—and even adequately testing them has proven to be a formidable challenge.
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Sorry to take up so much space on this Forum/Thread to Post what should be obvious to any who claim knowledge.