whlzki

I see... so even though the light has shifted from the distant galaxies, the speed is still constant? And so is that why we say the 'visible universe'? the part of the universe that we can detect?

I wasn't sure where to ask such a simple question - so please accept my apology first for my complete lack of knowledge. So... This one simple thought threw me off completely. And I knew it sounded stupid, but I just couldn't get over it! My physic's teacher is out of reach, so I had to turn to the internet for some solid answers. If high level cosmic background waves from the big bang stretched over time to form longer waves (which can be recorded and thus, we can calculate the age of the universe (?)), why hasn't the visible light waves from the very distance galaxies stretched? What is the difference between the visible light of the EM spectrum and the 'light' we see from distant stars? Aren't they exactly the same things...? And continuing from that thought... If light travels in photons (which I believe to be travelling in waves), why does light have a constant speed that will last forever(?)? ... I think I'm missing the point and confusing completely different things together.