Last night I watched journey to the edge of the universe and what a fantastic and thought program it was

[Liza23l]

As they got many thousands of light years and millions of years in the past away from earth and towards towards the big bang I couldn't help but notice it seemed to be much speculation and this made me think that is it possible that a mistake could be made which would take us in a completely different direction from the truth which we would now believe as our reality spurning other theories from this untruth till we're kind of making up as we go along and filling in the gaps as this seems to "make sense" ?

[NazNomad]

"...is it possible that a mistake could be made which would take us in a completely different direction from the truth which we would now believe as our reality ..."


Like, errm, religion, you mean? ;-)

[jomifl]

A lot of the speculation of astro physics is based on assumptions that fit with known 'facts'. They are by no means yet proven and we could still have a change of direction as has often happened. we will just have to wait...

[Liza23l]

Naznomad that's actually a good point and a possibility regarding religion.
Jomifl It really is almost like a giant puzzle where we have only some of the pieces.I suppose if we had all of the answers it would probably take away some of the mystique of it all.

[jake-the-peg]

As you get further away in time it becomes harder and harder to fill in the fine detail.

That doesn't mean you should doubt the doubt the big themes.

The big bang for example has some of the most spectacular proof in the history of Science.

It starded with Edwin Hubble discoverring that all the distant galaxies were rushing away from us - the further they were away the faster they were going.

The only way of explaining this was as if the Universe was expanding carrying all the matter with it (Sometimes people mistakenly think of it as a big explosion which is quite wrong).

Then people started to say well if that's the case there should be an "echo" a background temperature the same where ever you look in the sky and they calculated how much it should be.

Some years later a couple of researchers (Wilson and Penzias) found this "echo" not knowing what it was. A researcher in the field recognised what it was and it matched the pedicted amount to within a few percent!

Now you might call that "making it up as you go along" but I certainly wouldn't.

What does happen is a rather Darwinian process whereby theoreticians come up with ideas to explain things we don't fully understand.

That's not as easy as it sounds because it has to be mathematically consistant with what we already know.

Then experiments and observations kill off the ones that don't match the predictions or confirm the predictions just like Wilson and Penzias did.

If theory procedes too far beyond observation you can build a bit of a house of cards ( that happened in the 17th and 18th centuary with somthing called Phlogiston but that's another story).

Keeping experiment up is why so much time and money has been spent on things like building the Large Hadron Collider at CERN and the new breed of super telescopes.

[Ethersapien]

If theory procedes too far beyond observation you can build a bit of a house of cards ( that happened in the 17th and 18th centuary with somthing called Phlogiston but that's another story).

Some might say this sort of thing has also happened much more recently, the predictions of string/M theories are presently far beyond the realms of experimental testing for the most part. However I believe results from gravity wave experiments may go some way to confirming or refuting Ekpyrotic M Theory in the near future.

If they find relic gravity waves from the big bang this would make it hard for the Ekpyrotic version of M theory as it does not have a "Big Bang" as such, rather a much more gentle coming coming together of Branes in a dimension distinct from the four we know and love.