Did you know we offer a Winter School course in Communicating Science? If you’re interested in science writing for both specialist and non-specialist audiences, presenting to communicate science and the use of emerging online social media in science communication, this is a great course for you. If you’re interested, check out “Communicating Science” in course outlines for more details.
Over the coming weeks we’ll be showcasing blog posts written by Communicating Science students during their course last year. The first of these is “The Big Bang; now how it sounds” by Hayley Bunn.
The question of how the universe began or developed into what it is today is one of the biggest unsolved mysteries and to this day is full of ideas and controversy. When asked about how the universe began, whether you have a definitive opinion or not, and excluding religious views, the first thing that will come to your head is the big bang. Now this is not because it is the title of this blog or because it’s your favourite TV show, but because it is the most widely accepted theory, however is very commonly misunderstood. In science, a theory is an attempt to explain why or how something works. It is strongly based on facts and can be disproven but not proven. If disproven then the theory will undergo evaluation and modification in order to explain this new piece of evidence.
So what is the big bang? Well about 14 billion years ago there was nothing, then all of sudden out of nowhere (literally) there was a fluctuation of the “nothing” that caused this “nothing” to explode into “something” that we now call the universe. Suddenly there was time, space, matter and energy. Does this really make sense? How can there be something from nothing? Well that’s because surprisingly enough the big bang, although suggested by its name, was not a big, loud, extravagant bang that created something from nothing. In fact the big bang, for one, is a theory that makes no claim as to the origin of the universe. The big bang theory describes the process by which the universe developed from the time it came into existence to how we know it today. This particular misconception of the explosion is probably one of the biggest areas for scepticism, where in fact the big bang theory describes the process as an expansion. The figure below shows a good illustration of the difference between the two, where explosion is defined as a sudden and violent outburst and an expansion being the action of becoming larger.
The theory of the big bang first came from an astronomer named Edwin Hubble who observed that a star further away from earth, moved away at a faster rate. This is known as the expanding universe. The debate as to the exact relationship between the distance and speed of the object from the observer is still going on today. In order to rationalise the big bang theory, a few assumptions about the universe need to be made such as; the laws of physics remain the same; the universe is the same in every direction; and that earth is in no special position in terms of observation. However reasonable, these are still assumptions, but without them would it just be fact? There are a variety of alternative theories floating around with a slightly different angle such as the steady state universe, oscillating model and the hologram universe. Firstly I will talk about a theory that is quite similar to the big bang and makes some of the same assumptions. This theory is called the steady state universe; it describes a continuous deposit of matter throughout the universe, taking into account the apparent expansion. The main difference between the steady state and big bang theories is that the steady state assumes the universe is completely uniform and suggests an infinite universe with no beginning or end. The steady state universe theory, however, fell apart with the discovery of quasars (definition) that are so far away that they show a universe with a very different’ structure to how it is today. The final piece of evidence that swayed most astronomers and cosmologists back to the big bang theory was the discovery of background microwaves, which could only be explained by the big bang.
The oscillating model theory combines the theory of the big bang and also a theory known as the big crunch, which is essentially the ‘exact’ opposite of the big bang. The oscillating model describes an infinite series of big bangs and crunches. So is this therefore suggesting there are multiple universes? or that ours will have an end and in doing so be the beginning of another universe? Another theory known as the eternal inflation theory also presents the idea of a multiverse. The most recent theory suggests that the universe as we know it is a projected illusion or in other words a hologram. This theory in particular is quite complex, however is important to mention. The basic idea I get from this theory is that what we see as a 3D world is comprised of 2D matte,r like a TV world which is 3D but is 2D on the screen.
As you can see the origin and development of the universe is not only a controversy but is a very complex idea to understand. How can we know how it started if we weren’t there? So next time you walk out side take a look at your surroundings, have a think about how we might have got here, what is the first thing that pops in your head?…….
“Our whole universe was in a hot dense state, then nearly fourteen billion years ago expansion started. Wait… The Earth began to cool, the autotrophs began to drool, Neanderthals developed tools, we built a wall (we built the pyramids), math, science, history, unraveling the mystery,that all started with the big bang (Bang)!”
-The Big Bang Theory