Wednesday, April 3, 2013

A (very) Brief History of the Universe

One of the pleasures of looking at the stars at night is trying to figure out what all the stuff out there really is and how it came to be.

Some of the stuff you will see includes giant gas clouds where stars are born, and like everything that is born, death is inevitable.
The death of stars is nothing short of dramatic; they can explode in a supernova (a really really huge explosion) and colapse into a black-hole (not just the stuff of science fiction), leave a neutron star nuke behind (really exotic stuff), turn into a white dwarf (some really dense objects) or recycle the material to fashion a new richer solar system.

So, through many ambitious and exotic theories and many a rigorous observations, we think we know how the universe came to be. So, I will try to give a very rough account of the creation story.

Once upon a time...-let me re-phrase that- as time and space (well, space-time if you want to be all fancy and accurate) did not exist, as a matter of fact nothing did, zilch, not even a void or anything, just absolute nothing!
At this beginning, the universe and everything in it was squeezed into one very small point. Now, I have to mince my words as the word 'small' cannot apply where space does not yet exist.

All of a sudden (Chuck Norris must have sneezed if you as me), this point expanded explosively into the nothingness, superhot (and superfast) in every untouched direction.
So hot was the universe then that any sort of normal matter could not have existed until the universe was cool enough to allow this. I like to think of it as one trying to build a house of cards during a 8.5 magnitude earth-quake (figure is purely arbitiary).

The next almost emmidiate stage (inflation) of this hot universe caused the occurrence of some familiar (and anti-familiar) basic particles that flew around everywhere forming stuff we call plasma (a very hot gas).
The universe was then like a huge cloud that looked the same in every direction and as soon as the electrons were slow enough to marry themselves to protons by the powers vested in the electro-magnetic force, atoms specifically the hydrogen atom (one electron - one proton) were born.

The fog slowly cleared as, still expanding, the universe cooled enough to allow the conglamoration of cloud-like structure made entirely of gas that we fancy calling giant molecular clouds. And out of these giant clouds came about conglamorarions of stars that formed galaxies, which (each with billions of stars) are the building blogs of the universe today.

Out of one of these galaxies was one James Dean of a supermassive star that quickly used up its hydrogen fuel and thus succuming to its gravity (gravity won over the heat-pressure).
It collapsed in a supernova that ejected tons of new comples material that was cooked in the star during its lifetime.

The cloud of dust that was left behind had enough hydrogen to create another star at its centre and the rest of the material swirled around it.
The swirling cloud became a myriad of bodies; planets that counted innto the twenties, some rocky , some gassy, crashing into each other until eight survived (nine, for all those Pluto-philes out there).
One of the rocky survivors third from the sun started having life on its surface, single celled organisms that eventually became multi-cellular. One of these cosmic new-comers became smart enough to look up and around and wonder what all this stuff is made of and how it came to be.

Fast-forward to the present and the smartest of these bipedal beings started reading this column and thoroughly enjoyed it to the very end!
To get all philosophical on you, let's imagine a thought experiment that features the whole 13.7 billion years of the universe's history on a typical 12 month calendar, where the big bang is on January 1midnight and the present is on December 31 just before midnight.

Among other timescales, the appearance of humans (civilization to be exact) is only 0.16 of a second before midnight.
On that note, it's safe to say we haven't been around a very long time and I cannot help but question our self-proclaimed superiority in the universe.

I'll leave it to the rockstar of a reader to decide. I hope the inquisitive reader will read up more on this very interesting topic.

Stay hungry, stay curious.

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