Discussion: Outer Space

They were posting completely unrelated posts to each other (12).

Oh well my bad.

Matt77 said:

They were posting completely unrelated posts to each other (12).

All those posts were about space.

Not really.

Did KoC just call someone on posting irrelevant stuff?

If I remember correctly they weren't on any topic. They were like weird quotes.

I'd find them but I don't know which page they were on. They were stuff like MEAN GREENE GET IN HERE (it was in capitals) and some random quotes.

@novus: Is this your new account ? what was your old account

@Nightmare: Hi there! I do remember your name and yes I did use to post on D&D. Sadly I barely get on SC anymore, but glad to see you again! Hopefully I clarified some points. I don't know if the "feel sorry for anyone who is arguing against you" is meant to be taken as an insult or a compliment xD. Anyhow, good to see you . P.s, I stopped reading after page 10, I'll read more later on.

Oh and excuse typos and grammar, CBA right now.

Before I start, want to know what is the Big bang theory ? scroll to the 2nd last paragraph of the post (or somewhere around there)

A theory is something which has been tested and to some degree proven

That is not completely correct. Science realise on inductive reasoning rather than deductive, that is why you can never prove a claim in science. You have to take in to account the problem of induction which can be exemplified by the black swan example. Hence in science, you never prove a theory, you try to disprove it. And if after a while you can't disprove a theory and as it begins to make sense of more data, the theory gains more and more credibility. In science, all theories can be falsified, the hot big bang model has not been falsified.

look at radio waves, gamma, and other waves and say that some 13 billion years ago such and such happened. That I believe is just scientists making something out of nothing.

It is not simply the case at looking at the EM spectrum and saying different wavelength and concluding that the universe is 13.7 Billion years old. There is a plethora of evidence that backs up the HBM(hot big bang model). I'll go through some. Einstein came up with his theory of general relativity, in essence is a theory of gravity and tells us how space-time behaves in presence of matter. GR has been vindicated by several experiments and it has yielded useful predictions. The evidence of it comes from using number of observations e.g GR predicts the orbit of mercury around the sun to be much more accurate value than Newton did, you also have evidence from gravitational lensing (prediction of GR and that has been observed and is now used to find far away galaxies), Gravity Probe b, GR predicted the existence of Blackholes and a lot more that I can't think off my head. But when Einstein came up with the theory, it didn't describe the universe as we knew it back then. Einstien tweeked one of the solution to his field equations (friedmann's solution) and introduced a new term that we now called the Cosmological constant (dark energy) which says that space-time is expanding (at that time, people thought the universe was static). Geroge Lamteire (spellings) used GR to show that the current picture of the universe was wrong and that it is actually expanding. The fact that universe is expanding was also a prediction of GR.

I was oringally planning on going into more detail, but I am being lazy so I am just going to summaries some points. Edwin Hubble later on found out that galaxies were moving away from each other and the further away they were, the faster they were moving. He was able to determine it because the wavelength of light coming from those galaxies had been stretched towards the red spectrum (blue light => short wavelength => closer to us. Red light implies => longer wavelength => further away from us). So he saw that light from distant galaxies was red shifted as if the wavelegnth had been stretched.

I'd like to make a point that Hubble wasn't really looking at galaxies but at stars with varying brightness called the cephide variable in galaxies, but for sake of simplicity, I stuck with galaxies.

This cause of stretching was attributed to expansion of space-time. But the nail on the coffin came with the discovery of the cosmic microwave background radiation, which is what you alluded to in your post. Now if it were true that space-time is expanding, then we should be able to detect radiation from the early universe and it must be red shifted (cooled down). And that is precisely what we found out, the hot gamma radiation from the surface of last scattering (when the universe was cold enough for plasma to slowly fade and light to propagate) should be a low energy radiation because the wavelegnth would have been stretched. And that is exactly what we found, instead of Gamma radiation (high frequency radiation) we found microwave(low frequency radiation) which implied that over the course of the universe, radiation has been stretched and it would only be possible space-time was expanding. This discovery was awarded a Nobel Przie in the 1970s I believe.

The hot Big bang model was further vindicated with the discovery of the accelerating expansion of the universe, which was also awarded with the Nobel Przie in 2011.

There are further points of evidence e.g abundance of light elements and a simple deductive argument from the 2nd law of thermodynamic, which implies that the hot big bang model is true, along with many other lines of evidences, some of which are more technical

I also come to question the supposed age of the universe, which if I remember correctly is supposedly 13.5 billion years old. If I am wrong do point it out. This having been measured based on calculation of how fast other galaxies are moving away from each other and all that

You can work out the age of the universe simply by doing 1/Hubble's constant. Hubble's constant is the rate of expansion of the universe and we used to have theoretical estimates, which were slightly off from the values that were obtained in early 2000s and more recently last year by WMAP and Planck respectively. The current estimate is 67.80Km/Mpcs. And it certainly isn't one of those things that we are not really sure about. This is basic cosmology.

I look at our suns age of 3 billion yrs old and still only being half way through it's life expectancy (another imo faulty claim) then look at all the black holes out there (while considering that they are formed from incredibly massive stars collapsing at the end of their lives), then look at all the forming and formed planetary nebulas (along with the assumed amount of time that we believe it takes them to form), then look at the age of our Universe, 13.5 billion years. Well I get the feeling that there have been some miscalculations, that and there are many scientists with inflated heads.

I am getting the gist of what you are saying, but perhaps you could elaborate more on it ?
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Having said all that I said, does this mean the hot big bang model is 100% correct and not debatable ? No it certainly doesn't. It has some problems. I'll do now what I should have done before and explain what is the hot big bang model.

The major confusion that most people have is that the HBM describes the origin of the universe. THIS IS NOT TRUE. HBM describes the evolution of the universe and the expansion of space-time. HBM assumes that the universe started off as a singularity (infinitely dense, hot zero dimensional "point") and then it expanded into the universe we now know and love (hate) and the universe cooled down. But this point (singularity) is still debatable and you have many models for the early universe, but none of them are considered viable theories just yet. We can really know much about the origin of the universe, until we have a theory of gravity that tells us how gravity behaves at a very small scale (quantum scale) because at "moment" of conception of the universe, it was very small and we don't know how gravity behaves at that scale (GR breaks down). You also have some other problems which I rather not go into at this point (3:30 am here), but they have solutions(still need to be backed up by more evidence). All an all, big bang theory has a huge explanatory power and is the best theory we currently have that accounts for massive amounts of data and is therefore an extremely good theory.

I didn't know the knowledge of the person who would be reading this, so I decided to keep somethings very simple and went into a bit more detail where I thought it was necessary, feel free to ask me to clarify a point and I'll try my best to do so

Now THAT is what you call a post.

Well when I have a keyboard I'll make some long posts.

Abdul said:

@novus: Is this your new account ? what was your old account

Mmm. You'd maybe know of Deadwing? Pretty positive we had a few, though short, conversations. I think by the time I started seeing a ton of your posts here, I was getting more and more inactive. :p

no one know if the space have edge or infinite some scientist only said that just because no one can prove that space have edge or infinite only GOD can tell that may be near future some one thus can tell that the space have edge

So you aren't an atheist?

^Obviously.
Not an atheist. Not the best at grammar either.
I'll happily assume it's because of being a non-native English speaker.

Well I guess that makes 4 for the Christian team.

You got a lot more than 4 around the world dont worry.

Well that's good.

Or the death of thousands of Muslims.

I guess it depends how you look at it.

Where did you get that?

Crusades probably