Why do scientist accept the big bang theory?

Answer 1

The BB model makes predictions about what we should see from our Earth. Other models predict that these things should NOT be seen, or (at best) fail to explain why they would be there.

As the predictions made by the BB (cosmic microwave background radiation, ratio of hydrogen to helium to deuterium, age of oldest stars, no old galaxies far from our Earth) are all confirmed as being true, honest scientists have little choice but to accept the BB as the correct model for our Universe.

Answer 2

Considering the true nature and process of Science, the best answer is:

Because it hasn't yet been proven wrong.

[edit] they accept it not because it hasn't been proven wrong but because of the evidence -- background cosmic radiation and the Doppler effect. there are plenty of things you can't "prove wrong" but it doesn't mean it is accepted among scientists. [edit]

Answer 3

The Big Bang model is not proven - it is not a scientific law. Technically, the Big Bang is not even a scientific theory, because it does not meet the requirements (See 'What makes a theory a scientific theory?') It is best to describe it as a model.

.

The Big Bang model is not complete - there are problems with the Big Bang model, in that it does not satisfactorily explain everything, such as dark flow. There are, however, sufficient specific phenomena that are best explained only through the Big Bang model, and as a result, the Big Bang model is regarded as the best known model to explain the origins of the observable universe. These phenomena include:

1. The observable universe is expanding in all directions. Projecting this expansion backward through time, we can extrapolate a single point about 13.5B years ago in which all matter in the universe came from.
2. Indirect evidence of the Big Bang exists in the form of cosmic microwave background radiation, which appears in all directions.
3. The development and distribution of quasars and galaxies is consistent with the current Big Bang model.

Answer 4

Redshift is just one of many undeniable observations that support Big Bang Cosmology. Indeed, a Steady State Universe could have the Hubble Red Shift we clearly observe. However, the latter can NOT explain:

1) The existence, isotropy, and spectrum of the Cosmic Microwave Background Radiation.

2) The ratio of hydrogen to helium in all parts of our Universe.

3) The ratio of long-lived isotopes to their decay products show that none of the former could have existed more than 10 billion years ago.

4) Quasars are seen far from us, but not close to us.

5) No white dwarf stars have been found older than 10 billion years.

Proponents of any alternative to Big Bang Cosmology are reduced to saying, about all of the above, "We have no explanation for what we clearly observe. We undeniably see these things, but we can't say why."

Answer 5

There is a vast quantity of astronomical observations upon which this theory is based. We can tell by Doppler shifts in stellar spectra that the universe as a whole is expanding, and has been expanding for quite some time. If we try to calculate what the universe was like in the past, it must have been smaller than it is in the present, since expansion makes it larger. The farther back into the past you go, the smaller the universe must have been. We then extrapolate back about thirteen and a half billion years, at which time the universe was compressed into a very tiny package (sometimes called the Cosmic Egg). The time when the expansion began, therefore, would have resembled a Big Bang. In addition to the extrapolation of the overall size of the universe, we have additional confirmation in the form of our observations of the cosmic background radiation that is left over from the Big Bang. It has been analysed in great detail and it is consistent with the theory.

Answer 6

The Big Bang theory is the currently accepted scientific theory for the origin of the universe. It is accepted over other theories because it succeeds in explaining the evolution of the universe and it agrees with scientific observation.

Answer 7

Because it's the one that best fits the known facts. There are some problems with it, but it's still the best theory we have.

Answer 8

It satisfies Occam's razor; it is the simplest explanation that explains everything we know about the subject in question.

Answer 9

Because nobody has come up with any better explanation of the 4 degree Kelvin microwave background radiation.

Answer 10

The Big Bang supports interpreted observational evidence for an evolutionary expansion of the universe and rationalization for a finite age of the universe.