The Universe is Rubber

We all know the Big Bang Theory, right? – and not just the TV show, as awesome as it is. For those of you who don't, it's basically the theory that before everything, our whole universe was in a hot dense state before, nearly fourteen billion years ago, expansion suddenly began. This theory is the most widely accepted one for the beginning of the universe, because it also provides a plausible explanation for several phenomena such as cosmic background radiation (radiation that is thought to be leftover from the Big Bang) and Hubble's Law (wherein the farther a galaxy is from another, the faster it’s moving away).

Others may be more familiar with the Steady State Theory, which suggests that the universe has no beginning or end, and that although it is expanding, its general appearance doesn't really change over time. However, this theory has never had much support, with several observations disproving it.

I'm pretty sure that these have already been taught to you in High School (spoiler alert for those who still are in High School). What they don't talk about, though, is the end of the universe.

Yes, the universe will eventually have to die, just like everything else. Sad, isn't it?

One major factor in deciding the fate of our universe is its shape. So far, physicists have hypothesized three possible ones, which are determined by the universe’s density. If what we’ve got is greater than the critical density (which, by the way, is 5 × 10-30 g/cm3), the universe is closed and curves like a sphere. If the density is less than that, it will curve like a saddle. This is known as a hyperbolic or open universe. But if the actual density of the universe is equal to the critical density, as scientists think it is, then it will extend forever like a flat piece of paper.

These shapes have corresponding levels of dark energy, which is responsible for the expansion of the universe. In a closed universe, there is a notable lack of dark energy. This slows the expansion of the universe, and gravity eventually ceases it, causing the universe to contract and collapse into one point. This is basically the reverse of the Big Bang, and is dubbed "The Big Crunch".

Meanwhile, in an open universe, the dark energy levels are so great that all the fundamental forces – gravity, electromagnetic, and strong binding – are overwhelmed. This indicates that, not only does the universe expand forever, but it does so at an increasing rate, causing the universe to freeze over due to the laws of thermodynamics, particularly the second law which states that entropy (or disorder) tends to increase in an isolated system. Over time, the universe will eventually reach a temperature very close to absolute zero. In that scenario, no motion is possible, and obviously, no life will be able to exist. This one is more commonly known as "The Big Freeze".

Now, in a flat universe, the universe still expands, but this time it does so at a decelerating rate. Dark energy will force expansion to increase at an accelerating rate over time, causing the galaxy clusters to further separate. This also leads to The Big Freeze.

You could probably think of the universe as a sheet of rubber. It’s elastic, and it can bend into various shapes or be squished to different sizes. It would most likely take the same amount of force to stretch rubber and to compress it -- and that's what might be in store for our universe. Which do you think would feel more gruesome?

Sources: 
Hawking, Stephen and Mlodinow, Leonard. A Briefer History of Time. New York: Bantam Books, 1996. Print [na]. WMAP - Fate of the Universe. nasa.gov. [nd] Web. July 16, 2014.

Zeeya Merali. What Does Dark Energy Mean for the Fate of the Universe? discovermagazine.com. April 17, 2013. Web. July 16, 2014.

Nola Taylor Redd, What Is the Shape of the Universe? Space.com. January 15, 2014. Web. July 25, 2014.

Article by Anne
Artwork by Nikki
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Anne’s childhood dream was to be an astronaut, before it was shattered at the thought of her leaving the country. Now, she studies BS Biochemistry to be a geneticist. She’s a physicist at heart, though, and plans to get a Masters degree after college. She likes video games that involve killing an average of 500 men a day, and is currently in a love-hate relationship with bowling (Check her Twitter at twitter.com/itsnotmydesign and Tumblr at tumblr.com/training-trainer).

Nikki is a girl that sometimes feels like a boy, and is also an all-around art enthusiast and a linguist that likes the mysterious sounds words make. She likes wearing round spectacles of any sort, playing with her makeup when she’s bored, and envisioning outfits for various kinds of occasions. She has a style diary here and maintains a twitter that experiences extreme lows and highs of activity.