Is big bang proven to be solid true?

[Asguard]

jmpet, i doubt it. That its the best aproximation we currently have is probably more accurate.

 

[James R]

Is big bang proven to be solid true? Just because we observe that the distant galaxies are flying away from us, we postulate that the universe was born from a big bang?

It's logical, wouldn't you say? If everything is flying away from us, then at some point in the past, everything must have been where we are. Right?

So far, how true is big bang according to the latest astronomical observation?
And, any evidence to prove otherwise?

The big bang is a complicated theory. It makes lots of predictions about different things.

The basics of the big bang (that there was one, etc.) have been confirmed beyond any serious doubt. Some of the details of exactly what happened in the first moments after the bang are still being worked out.

The thing to realise is that no single fact proves the big bang theory. Rather, there is an immense amount of evidence of different types that supports the theory. Chances are that knowing down one piece of evidence won't knock down the theory, contrary to what some people think.

The big bang is one particular take on certain evidence and a number of unproven ideas, like singularities and inflation. It has a number of serious problems with it that have not been addressed.

Not according to experts in the field.

We cannot know for certain that galaxies are flying away from each other.

All we need to do is look at red shifts to establish that. So, we can and do know.

At 10^-32 (that's 0. 31 noughts 1) of a second, matter was created so we have the whole universe in a size smaller than a cricket ball. A density trillions of times that needed for a black hole and black holes don't inflate or expand. Of course, a singularity is magical, so can ignore the laws of gravity.

The big bang was not an expansion of matter in a pre-existing spacetime (c.f. black holes as the collapse of matter in a pre-existing spacetime). Therefore, the big bang was not a "time-reversed black hole" or anything like that. The big bang was an expansion of spacetime itself, which is quite a different kettle of fish.

The big bang may turn out to be true in the end and it may not. We should not have all our eggs in one basket if it is shown to be wrong one day.

Are there any other viable baskets around? If so, I haven't heard about them.

1) I can't understand how should I imagine the space-time of this universe? Is it like an expanding baloon? Baloon has an edge, the peripheral, how about the universe? What is beyond the edge of the universe? You call it event horizon? What actually it is?

The balloon analogy commonly used must be understood correctly. The surface of the balloon represents the universe, not the inside and outside of the balloon. The surface of a balloon has no edge, in the same way that the surface of the Earth has no edge. If you walk around the Earth's surface, you never fall off the edge of the world.

2) Could there be more than one universe? I remember I read that there are scientists postulated that more than 1 universe is possible.

Maybe.

 

[jmpet]

jmpet, i doubt it. That its the best aproximation we currently have is probably more accurate.

Good opinion you have.

 

[Ophiolite]

The thing to realise is that no single fact proves the big bang theory. Rather, there is an immense amount of evidence of different types that supports the theory. Chances are that knowing down one piece of evidence won't knock down the theory, contrary to what some people think.

People who insist a theory should be falsifiable ought to feel slightly uncomfortable about that.

 

[James R]

People who insist a theory should be falsifiable ought to feel slightly uncomfortable about that.

This is where falsifiability as the sole criterion of the scientific nature of a theory falls down. Scientific theories, especially comprehensive and long-standing ones, are seldom tossed out the moment a new piece of data is suspected not to fit. What happens much more often is that scientists first look for errors in the new data. If they can't find any, then they might consider modifications to the theory. If those aren't possible, then the whole theory might need to be chucked.

Even when theories are occasionally chucked out, it is often not a baby-with-the-bathwater matter. For example, Newton's law of gravity was technically falsified by Einstein's general relativity, but you'll still find Newtonian gravity used by professional physicists and engineers all the time. Why? Because Newtonian gravity is in many (perhaps most) instances an excellent approximation to Einstein's theory, and it's far easier to use than Einstein's theory.

 

[Norsefire]

nothing can be "proven true" only more correct than it was yesterday based on observable data we have collected today. Look at newton's theories, they were correct enough at the time but we now know they are wrong (though they are right enough we can still use them for most things) and have been replaced with enstine's theories. Something else will come along eventually to replace enstine as well

Unless Einstein is just plain correct. I agree with you, but there are things that are hard facts and many theories which might simply be correct.

 

[Saint]

If you walk around the Earth's surface, you never fall off the edge of the world.



Maybe.

my question, what is above and below the surface?

 

[Norsefire]

That doesn't mean there isn't an above or below, James. So what's outside the universe?

 

[Asguard]

Unless Einstein is just plain correct. I agree with you, but there are things that are hard facts and many theories which might simply be correct.

name 1. What i mean is that even things which common sense would say are provable arnt are only falsifiable. Take one example, the tassie tiger, we cant currently prove it exists only that we havent found one yet and so on the surface we could say that you can only prove there existance true but lets look at a senario

A person brings in film of a tassi tiger, that can be proven NOT to be of a TT
they find a live animal, great there are TTs. Nope genetic (or something we havent invented yet) analisis proves its NOT a TT

All things can be disproven but they cant be PROVEN. Even that your responding to my post is only held as correct until evidence arises that its false (for instance that im in a mental hospital and you are all parts of a delusion im having including that computers exist)

 

[D H]

my question, what is above and below the surface?

That doesn't mean there isn't an above or below, James. So what's outside the universe?

The balloon analogy is just that: an analogy. I think one needs some minimal familiarity with the concept of non-Euclidean geometry to appreciate the analogy.

Reading a book written over a hundred years ago, Flatland: A Romance of Many Dimensions might help. The wikipedia entry points to some online versions of the book. In a nutshell, Flatlanders live on a plane. There is no such thing as above or below to the Flatlanders; the plane is their universe. Instead of a plane, suppose their universe is the surface of a balloon. Still two dimensional. There is no above or below; asking that is in a sense a nonsensical question but it is also an indicator that the balloon analogy is not a particularly good analogy.

 

[Ophiolite]

The balloon analogy is just that: an analogy. I think one needs some minimal familiarity with the concept of non-Euclidean geometry to appreciate the analogy.

I disagree. I know nothing of non-Euclidian geometry. If Playfair's postulate came up and slammed me in my Riemann curvature tensor I would just think I had stumbled over a pebble.
What one does need a minimum understanding of is analogies.

In the referenced analogy the universe is likened to the the surface of a balloon. (We shall ignore time and consider only the three conventional spacial dimensions.) So, the universe is three dimensional, the surface of a balloon is two dimensional. We are likening the universe to the surface of the balloon. Therefore anything beyond the surface of the balloon, internal or external, does not exist in the analogy.

Hence to ask a question like, what is inside the balloon means one has not understood how analogies work. The rule is we are likening these aspects of this thing, and only these aspects, with these aspects, and only these aspects, of another thing.

 

[leopold]

Dear me Leopold. I don't know how you do it. Such incredibly wrong ideas about so much. An encyclopedic cornucopia of incomprehension.

huh?

The Miller-Urey experiments simulated a hypothetical primordial atmosphere.

isn't that what i said?

We now know its composition to have been wrong.

it was? i never knew that.

Moreover, at this point the BIg Bang theory was not the favoured hypothesis.

yes, i know. i never stated otherwise did i?

The selection of the atmospheric components did not depend in any way on the Big Bang or Steady State theories.

correct.
it was based on the primordial conditions on earth if the solar system was spawned by the big bang

The experiment certainly did not deal with the formation of the Earth.

see above.

Actually, they have not found the same compounds except in a very general sense.

http://www.sciforums.com/showthread.php?t=92057

Even if they had it would say nothing especially relevant about the Big Bang.

earth based experiments that simulated an atmosphere on a planet and space debris yielding the same results suggests the assumptions made in the earth based experiment was correct.

The Big Bang is not a local event, it is metaphorically and literally universal. Your opinion upon this point is completely wrong.

there were two possibilities, i named them both.

 

[Ophiolite]

Dear me Leopold. I don't know how you do it. Such incredibly wrong ideas about so much. An encyclopedic cornucopia of incomprehension. ”

huh?

It was a polite way of saying you were talking unmitigated crap.

The Miller-Urey experiments simulated a hypothetical primordial atmosphere.

isn't that what i said?

Your claim was that this was not just any primoridial atmosphere, but one that "would have formed from the big bang." That is simply incorrect. Completely incorrect. The basis of the atmosphere used was the consensus view of that time - since largely discarded - that the Earth had a strongly reducing atmosphere.

The selection of the atmospheric components did not depend in any way on the Big Bang or Steady State theories. ”

correct.
it was based on the primordial conditions on earth if the solar system was spawned by the big bang

There is so much wrong here.
It was not based on "the primordial conditions if the solar system was spawned by the Big Bang".
Miller and Urey did not sit down and ask themselves, "if there was a Big Bang what would the composition of the early atmosphere have been?"
You claim they did. (Fine, you will have no difficulty finding the passage in their publications that deals with this.)

But let us pretend that they did base their atmosphere on what the Big Bang would have 'spawned'. In that case why are you agreeing with me (you say correct) that the atmosphere they selected did not depend on the Big Bang? Pure contradiction on your part.

“ Even if they had (found the same specific chemicals in the Miller-Urey experiments as in meteorites) it would say nothing especially relevant about the Big Bang. ”

earth based experiments that simulated an atmosphere on a planet and space debris yielding the same results suggests the assumptions made in the earth based experiment was correct.

But no assumptions were made in the experiment about the reality or character of the Big Bang. That is the central point you keep misunderstanding.

To repeat, the Miller-Urey experiment offers nothing in support of (or evidence against) the Big Bang. Your claim to the contrary is ill founded.

http://www.sciforums.com/showthread.php?t=92057

The issues I have with your interpretation of the work of Higgs and Pudritz I shall deal with elsewhere.

 

[leopold]

i was under the impression that miller-urey duplicated the primordial conditions of an earth that was created from stellar dust cloud.

 

[Norsefire]

The balloon analogy is just that: an analogy. I think one needs some minimal familiarity with the concept of non-Euclidean geometry to appreciate the analogy.

Reading a book written over a hundred years ago, Flatland: A Romance of Many Dimensions might help. The wikipedia entry points to some online versions of the book. In a nutshell, Flatlanders live on a plane. There is no such thing as above or below to the Flatlanders; the plane is their universe. Instead of a plane, suppose their universe is the surface of a balloon. Still two dimensional. There is no above or below; asking that is in a sense a nonsensical question but it is also an indicator that the balloon analogy is not a particularly good analogy.

I understand the "flatlanders" concepts however we have to think of everything as a whole; yes, to the flatlanders there is no "outside" and perhaps to us there is no "outside", but technically there is something that exists within the balloon and outside, and so technically there is still something "outside" of the universe, no?

 

[AlphaNumeric]

but technically there is something that exists within the balloon and outside, and so technically there is still something "outside" of the universe, no?

No, you do not need to embed such 'universes' as the ones described by the FRW metric into larger space-times.

 

[Ophiolite]

i was under the impression that miller-urey duplicated the primordial conditions of an earth that was created from stellar dust cloud.

Whose origin did not require, or depend upon the reality of the Big Bang.

 

[Fraggle Rocker]

I would argue that the flat earth is to the round earth as Newton's classical physics are to Einsteinian relativity. Both a flat earth model and Newtonian physics work great at certain scales. When you move beyond those scales you need a different, more refined model. There are many circumstances under which you can assume that the earth is flat and have things work out just fine.

The flat earth model was okay for small distances, but only for making a map or planning a journey. It was an impediment to understanding the motions of the sun, moon, planets and stars, something humans had been wondering about for ages, probably since before the dawn of civilization. The earliest astronomers were able to calculate the paths of the heavenly bodies using mathematics, but no one could turn that purely mathematical model into a physical model of a natural universe. It required belief in a supernatural universe, which is anathema to science.

i agree with you to an extent. Everyone knows (or should) that the earth is round but we ALL carry flat earth stuff (ie maps) which work well except close to the poles

My atlas has a very nice, accurate map of Antarctica and a similar one of the arctic region. I think perhaps what you're really referring to is the increasingly obvious distortion of the Mercator Projection as the "stretched balloon" model of the earth is expanded to include areas closer and closer to the poles.

We're happy with Mercator for the tropical and temperate latitudes because we were all raised on it. Everyone thinks Greenland is bigger than Mexico, Alaska is bigger than Brazil, Sweden is bigger than Iran, etc. It's biased to exaggerate the importance of the nations in the upper reaches of the Northern Hemisphere and that's why we all love it.

I'm not sure why you Aussies like it. Does it make Australia look bigger than China?

 

[Asguard]

i dont know, will check

i guess they look around the same size

 

[AlphaNumeric]

Atlases are the name for collections of maps, both in terms of your usual notion of maps and the more technical notion of manifolds. A manifold is a space where you can, in small regions, approximate it to arbitrary accuracy, using flat space, but in different regions you need different maps. You can do a map of the US which is roughly flat and the same for Antarctica, but they are not going to be the same projections from a sphere to a sheet. The important thing is that where the maps overlap (well not for the US and Antartica but say Europe and Russia) is that you can smoothly go from one to the other.