I have lots of questions regarding this topic so first just start with what is Big Bang ?
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I have lots of questions regarding this topic so first just start with what is Big Bang ?
If you tune your TV between channels then some of the fizzing snow on the screen is apparently the radiation after glow from the big bang, roughly 13800000000 years ago. The universe has been expanding ever since and is now approx 30 billion light years across, to get an idea of size, if you could travel at a million miles a second it would take you about 6 billion years to cross the universe.
Big huh? :)
The big bang theory came about first by noticing that the universe is expanding. We can see that it is expanding by examining the shift in the wavelengths of light coming from stars in other galaxies. When things are moving very quickly away from a one point of view, the light emitted from the origin is shifted towards the red spectrum. This is known as the "Doppler" effect. It is the same effect you get when you are standing near a train track, and hear a passing train blow its whistle... the pitch seems to drop as it goes past you.
At first, measurements showed that all of the observable galaxies were moving away from us at incredible speeds. Later it was also observed that all galaxies were in fact moving away from each other! This is why it is said that the universe is "expanding."
But expanding from what? The theory attempts to "wind time backwards" so that we can determine where things are coming from by where they are now, and where they are headed. If the expanding universe were on a film we could flip backwards and watch in reverse, we would see it shrink down smaller and smaller, and finally converge on a single point of virtually infinite mass.
If we start our observation at this point, and look forward, the universe "explodes" into existence, and begins to radiate outward with unimaginable force. This is what we call the "big bang."
Thanks 4 da info its very interesting , tell me how it formed ? how all of this started ? some gases combined and !!!BANG!!! universe was formed ? How ?
I hope you're joking... :rolleyes:Quote:
Originally Posted by Vortex
The Big Bang is still just a theory and has a lot of unanswered questions. Nobody really knows what it was or why it happened, and especially not how it started; those questions may never be answered.Quote:
Originally Posted by ^R^ed-$py
Well, apparently some of the fuzz on your screen is background radiation from the big bang. Approximately 1% if I'm not mistaken.Quote:
Originally Posted by pokilty
The Big Bang Theory is the theory trying to explain the phenomenon of the Big Bang.
Calling things 'just a theory' is like asking someone why they did something, getting the answer and then saying, "But that's just an explanation, WHY did you do it?"
The problem is that the common usage of the word "theory" is not the same as the definition of a proper scientific theory. Most people hear the word and think "speculation" or "idea." That's not what is meant when we talk about the Big Bang.Quote:
Originally Posted by wannywan
Here's a good explanation of the difference: http://en.wikipedia.org/wiki/Theory
Yeah, it happens all the time.
'Just a theory' is one of the most annoying things I hear. Because of this confusion, I've seen people state, "I don't believe in evolution because it's a theory."
Which is as semantically wrong as it is just plain wrong.
Everything in science is just a theory unless it can be proven mathematically. Even gravity is technically a theory. (Are there still hardcore christians that don't believe in gravity?)
If something is brought about that contradicts the current theory then it is revised or thrown out all together (the theory, not the evidence,) that's part of the scientific method. Ideas that don't do this aren't called theories (creationism,) they are known as myths.
All theories have holes in them, but they are being filled in. Even gravity is still incomplete (it doesn't explain the rotation of galaxies,) that doesn't mean that it's wrong.