THE ORIGINATION OF OUR UNIVERSE
There are many theories as to how existence became possible. The ancient greeks were one of the first civilisations to venture towards an understanding of our origination, and question our very existence. We have progressed rapidly since then, with the vital contributions from Pythagoras, Philolaus, Aristarchus, Aristotle and Ptolemy. Now we no longer question whether the Earth is round, or what orbited around what. In this day and age we have a much more imposing question, 'How did we get here?'.
THE BIG BANG THEORY
The Big Bang theory is the most accepted and thought out of all of the theories explaining the origin of the universe. The theory states that at a point in time 13.7 billion years ago, all matter was compacted into a small ball with infinite density and intense heat, known as a singularity. This singularity is theorised to be our universe. The universe then rapidly expanded into what astronomers have called, the Big Bang. According to this theory the explosion formed the universe in an instant. Our universe is believed to have continued expanding through time.
Cosmic background radiation is the main proof of the Big Bang theory, as well as the relationship between Edwin Hubble's discoveries and our expanding universe. Cosmic background radiation was discovered in 1965 by Arno Penzias and Robert Wilson. CBR is supposedly the remaining radiation from the development of the universe, the Big Bang, and the fact that this radiation is detectable greatly supports the Big Bang theory. Edwin Hubble's discoveries support the aspect of the Big Bang theory where it is theorised that the galaxy is expanding. He observed the spectra of galaxies and measured the 'Shift' of spectral lines in the galaxies over time. Hubble studied the relationship between a galaxy's distance and speed at which it is moving away from Earth. He concluded that the farther away a galaxy is, the faster it moves away from Earth. The majority of galaxies he observed appeared to be moving away from our galaxy, therefore having higher red shifts. |
This diagram displays the concept of the Blue and Red shift. As you can see when the spectral lines are closer to the blue region of the diagram, the observed is moving towards us, and vice versus.
Snap Government, 2006, Dark Energy. no Sponsor, 12th September 2015.
http://snap.lbl.gov/science/darkenergy.php |
THE STEADY STATE THEORY.
The steady state theory is a lot simpler than the Big Bang theory, except it isn't except it isn't accepted as widely due to it's lack of explanation for certain discoveries. The theory asserts that the general character of the universe is not changing over time (hence, a steady state). The theory proposes the idea that the universe has always looked the same, no matter the view point or time and essentially that the universe is uniform throughout both time and space.
Any evidence that proves the evolution of the universe is evidence against the Steady State theory, for example, Hubble's law and Cosmic Background Radiation. There is no longer any stable evidence supporting the Steady State theory, following its demise in the 1960's after the discovery of CBR. Cosmic background radiation is electromagnetic radiation from the sky with no discernible source.
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Physics of the Universe, 2012, Big Bang Background. No Sponsor, 12th September 2015.
http://www.physicsoftheuniverse.com/topics_bigbang_background.html |