Presentation on the Expansion of the Universe

insertion on the Expansion of the UniverseGood morning/afternoon, at once I will be talking to you ab kayoed the passing worldly concern. The topics that I will be covering now would be thesis statement, Background to the Universe Expansion, what causes it to expand? what evidence be in that location to support it, did it start from the Big flack? And what happens to the galaxies as it expands? These topics will be supported through the key supposition how gravity is related to the expansion of the man? I would like to beget with my thesis statement, the earth of discourse is expanding and as the existence expands the galaxies are only told moving away from each new(prenominal) in all directions and the once that are the farthest are moving the fastest. Does this mean that no case what galaxy we are in, everything is expanding?, is our galaxy the milky way also expanding? Does this mean that the full solar system is expanding? What ab away the things on earth? An d also does the fare of matter present also increase through the expansion? The practise to all these question relates back to the year of 1929 when an astronomer at named Edwin Hubble discover that the universe is expanding through the biggest compass that was available in his time. He pointed the telescope at distant galaxies and for the first time we could see those distant galaxies and he noticed roughlything very funny about the luminosity from them. The giddy from those galaxies were bolshy shifted which means those galaxies were moving away from us.Redshift Hubble constant like a shot like sound, on the loose(p) travel out from its source as a wave, different work have different wavelengths, blue light have a comparatively short wavelength whereas blushing(a) light have a relatively durable wavelength. Consider an object that moves away from you, as it continues to move then the wavelength of its light get stretched and moves towards the red end of the spectrum a nd so we claver this a red shift. Every galaxy that Hubble looked at was rushing away from our galaxy whitish Way. He realised that the further away the galaxy was, the bigger the redshift of the light and that meant those galaxies were moving away from us at faster and faster speeds. Its not that the galaxies are moving apart but its the accompaniment that the entire universe is expanding, the whole of aloofness is getting bigger. This discovery take us to an astonishing conclusion that all the matter that we see today must at wholeness time have been in a very dense and hot region of space and that is the phase we call the Big Bang.The fate of the universeIt is taken around 13 bingle million million million years for our visible universe to get to where it is today, but what does the future save and tell us about ten years ago, cosmologist have deuce-ace theories for what would happen to our universe one the open universe if there wasnt enough gravity, then the universe would keep slowly expanding for ever and compose infinite. Two the closed universe that the amount of gravity in the universe would slow its expansion down until it collapses back in on itself, And tierce the flat universe that there would be just a ameliorate amount of gravity so that the universe grows to a particular size of it and then stops. just then astronomers discovered something completely unexpected. The expansion of the universe is accelerating and they realised that there must be something pushing on it and we go intot know what it is, but we know it is there.In early clock of 1900s, astronomers presumed that the universe was slowing down and that the gravity would hold everything down and maybe will come back and explode again and people verbalized this idea with a mathematical expression that the universe is flat signification that the universe will continue to expand slowly without ever stopping. But relatively now in this 21st century, astronomers were trying to find out that at which rate is the universe slowing down using frightful technologies like telescopes all around the world and observing the dark wickedness sky and the supernovas referring to the standard brightness that relates to the distances. But what they actually discovered was that the universe is not slowing down. But it is accelerating the universe is accelerating at its expansion and do you know wherefore? No one knows why, no one knows why but what you hear these days is the expression dark matter or dark energy and these are mathematical concepts which explain the gravitational attractions of galaxies, clusters of stars and their expansion. Doesnt it seem logical that something is out there that is causing the universe to expand, it fanny be considered here also on Earth but its the fact the we arrogatet know how to detect it.The Hubble diagramNow days we have the distance that Hubble measured using the sapphires and the velocity he measured using the red shift and the blue shift of the spectra. So we are scientists we like to make charts and graphs so lets graph these two things, the galaxy velocity versus the galaxy distance and this is the chart that Hubble made. from each one of the point on this graph is a unique galaxy and what you stop see here is that many, in fact most of the galaxies are redshifted. Moreover, galaxies that are further away are higher redshifted than galaxies that are close. Now yes there are couple blueshifted galaxies on this plot if you look closely, and thats finely because these are galaxies that are actually very close to us such(prenominal) as the andromeda galaxy and it turns out that we are gravitationally attracted to one some other, we are pulling each other in and we will in couple billion years slam into the Andromeda galaxy and will make one big new galaxy. Now we can miss those local effects but the general overwhelming effect is that galaxies that disengage faster from us, the more(p renominal) distant they are and this is the Hubble law. And this of course, is another c counterchange in our understanding of the universe because what it suggests or supports is that instead of living in just a universe with the galaxies that are sort of hanging out and not doing much, we are actually living inside an expanding universe.The grid expanding universe representationThis grid represents space and each little square is a bit of space and these little dots are the galaxies that recede in space and now galaxies are free to move through space, they do that similarly like I said that we are going to hit Andromeda and thats because both galaxies are moving through space at one another. But the other thing that happens is that the galaxies move away from one another because space itself is expanding between them.so here is space at some beginning time and here is space at a subsequently time when the space itself has expanded. You can see that the galaxies havent travel r elative to the grid of space but theyve moved from one another because the space itself has gotten much larger and no matter where you are, no matter which galaxy that you are in, if you look at all the other galaxies they all appear to be moving away from you with a velocity that is proportionate to their distance, so things that are moving away faster are more distant from us.The balloon specimenYou can also think of the example of a balloon being blown up, just imagine the open air of the balloon and there are little dots that are little galaxies all over the resurrect of the balloon and as you blow it up the surface itself increases and so all the little dots representing galaxies move away from all the other little dots on the surface and are accelerating in their expansion and this is the universe that we live in now. This agency that is causing this accelerating expansion is called the dark energy, so it appears that although we answered all of the big questions, we are s till left with many more. We dont know what the dark matter is but we know that it is there. What happened in the early stages of our universe? We dont know the answer to that either. We havent got any clue to as what our universe is going to be doing billions of years of now, we just dont know because we dont understand it but with the astonishing technologies that are available to us today and through the discovery of Edwin Hubble, we know one thing for sure, the universe is expanding.