1. All galaxies are redshifted. (redshift is a doppler-like effect on the frequency of light, faster somehting moves away the more it is red-shifted) 1. The further away a galaxy is the greater the redshift (this is what Hubble discovered, by measuring the light using spectroscopy). This is the essential fact of the universal expansion which is measurable from earth-based telescopes. A baseline for distance can be established through the use of 'standard candles', supernova that explode with the same intrinsic brightness (which happens when stars are of a certain mass). By measuring the brightness of the supernova you can work out its intrinsic brightness and thus the distance of the galaxy it contains.
When I raised this point at the CofE junior school I went to, it was explained to me that God does all the good stuff and Satan does all the bad stuff, and God let's him so as to test our faith. I pointed out that if God needs to test our faith and he has the ability to just stop Satan and doesn't, then he's not a very nice man. It was made clear that God works in ways we can never understand and if that's what he chooses then so be it. I chose to stop believing in him.
So who's been to the end of the universe to check its accurate? and I think my point is being heavily missed. It takes a level of faith to believe in higher science, as most either cant, or wont, understand the info behind it. As such, the 'preachers' say believe us, so they do. For things like creation its a great example. The theory and science seems to be there, as it hasn't been disproved rather than proved, therefore its fact. Exactly like you bible bashing Texan gun-totting god-fearing cowboy
How do you know that there hasn't. Was our big bang the first? Will this universe continue expanding until it reaches some finite point at which time it creates another big bang and we start over again? We don't have all the answers. Its possible we will never know everything. I think the fact that we understand so much already, most of it figured out in just the last few years, is truly astonishing, especially when you consider we here we have come from and how long that process took.
Oh and we can tell the mass of a star by spectropy too. And spectroscopy works because the PHYSICAL THEORY OF ELECTRON ENERGY LEVELS works. Why does it work? Because it makes a prediction for the values of energy levels in an atom and when we go and look the energy levels are PRECISESLY those values. The energies are quantised so the electron cannot have inbwtween values. When they get excited (by photons) they jump up to the next (or higher) level absorping presisely that ammount. Then they drop back and emmit a photon of the same value. Wondered why street lights are that horrid orange? That's the excitied electrons dropping back and emiting light of precisesly that frequency. So in stars various heavy elements present in the star's atmosphere absorb photons (at quantised values) so we see a pattern of dark absorbption lines in the stars spectra. These lines can be seen to be shifted into the red than they would normally be in fast receeding galaxyies. Thus the galaxies are receeding. Thus the universe was more dense in the past.
Science starts out with a theory then devises tests to ascertain whether that theory can be proven. Until its proven it remains theory. Science starts out with a story then tells people its true. No testing of that story is allowed. Science is the new religion. I believe in it. I have faith that science will continue to explain where we originated from and will determine where we go. Science will continue to improve my short time on this planet. I even believe that science will probably hasten our demise too. But I'm OK with that as I get to be among the stars when I'm gone and cool with that.
When you look at star light you ARE looking back in time. Nope. It takes a degree of laziness not to bother to learn about science. The information is there, it is self consistent and has supporting experimental evidence. This is absolutely NOT the same thing as beleif in religion. Nullius in verba - as it says over the door of the Royal Society (take noone's word for it)
Great wind-up Bradders, nice one. Next thing you'll be provoking us into recapitulating every scientific paper since Isaac Newton so as to demonstrate the validity of the whole of science. Best settle in for a long thread.
OK, just to add another slant on this. The universe is expanding and therefore must have been much smaller, to a point where it was just energy with no space or time or dimension. Then, for some reason, it came into existance with a set of 'laws' that cannot be broken. Without these laws, the universe wouldn't exist at all, for example, gravity. How are these laws governed? Why can't they be broken? Why these laws and not some others? I'm totally on the side of science but these are the questions that interest me.
easy...God made them and allowed Man to prosper until the point his arrogance became such he destroys himself then it starts again About as factual as the big bang theories anyway ;-)
Those are interesting questions actually Kenoir. There are a couple of assumptions in physics one being that the laws of physics are unchanging over time. But there's nothing to prevent you supposing that over very large distances (many times greater than the visible universe) the laws or contants are a little different. As long as the two regions are causally unconnceted it shouldn't be an issue (I think?). Also there are some people that propose a kind of frothy universe with bubles of different regions and we happen to be in the one with the laws and constants we observe, then there's Everett's multiverse. But yes one of the big questions is WHY these laws and constants and not others? The anthropic principal is not considdered science (because its untestable) but I like the logic of it. Its great that we can ask these kinds of questions without being inserted into a burning tire though isn't it.
Speak for yourself, I like nothing better than being inserted into a burning tyre, beats wearing the spiked leg strap ;-)
No, Science examines the phenomena and devises and tests a theory that best fits those phenomena, as our understanding and reference points of observable and testable phenomena changes so does the theory. Any scientific theory is just the latest best explanation of what we have observed.
