Cosmology and the Universe
Explanation of cosmology, the universe and potentially everything
Cosmology and the Universe
Table of contents
1.5. further reading
1.5.1. see also
Cosmology - is it all Greek to you?
Of course it is - well the word itself. It comes from the Greek Cosmos (order) and Logos (word, reason, plan).
The modern interpretation of Cosmology usually refers to the study of the Universe in its totality - including humanity.
Our understanding is anything but extensive even though Cosmology can be traced back to ancient civilisations such as Egyptian (3400-30 BC), Babylonian (4000-300BC), Mayan (2000BC-900AD), and Greek (2800BC-300AD).
Religions throughout the world have used Cosmology to explain how an omnipotent, omnipresent being was solely responsible for creating the Universe. Hindu Cosmology even asserts that the Universe we live in is just one of many that have been created and died only to be born again. Funnily enough, this particular theory is gathering credence in today's theories on Cosmology. Some ideas have been around for a very long time.
The Catholic Church resisted any theories that did not place the Earth (thereby Man) at the centre of the Universe. Galileo (1564-1642) was charged as a heretic by the Church when he published his support for Copernicus's (1473-1543) heliocentric theory (that the Sun was the centre of the Universe). Galileo was forced to recant his support, and placed under house arrest for the rest of his life. We now know that not only is the Sun not the centre of the Universe, but neither is our Galaxy, and nor is the local group of galaxies that we belong to.
Another theory gaining popularity is that there is more than one Universe (Science Fiction writers please take a bow). The current (2008) estimation is that there are eleven 'dimensions' (Universes). This may explain why 90% of the matter in the Universe has not been found (perhaps it is in another Universe?)
The current (2008) estimate of the age of our Universe is 13.7 Billion years. There is general acceptance that the Universe came into being via a 'Big Bang'. This theory postulates that all the known matter in the Universe was contained in a 'Singularity' - an infinitely small point of initial matter, of infinite density and temperature. When this 'Singularity' exploded - the Universe was born. 'Big Bang' is an interesting phrase: since there was nothing else to compare it to, how do we know it wasn't a 'Small Bang'? Whatever, this still does not explain how the initial matter that formed the Singularity came into existence.
Over the centuries, as humankind's knowledge increased and instrumentation became more powerful and sophisticated, our understanding of the Universe expanded. However we now seem to have more questions than answers.
The vastness of space is beyond comprehension for most of us. How are we to imagine that light from our nearest star (beyond our own Sun - yes our Sun is a star, albeit it a rather small ordinary one) takes over 4 light years to reach us. (Incidentally the speed of light is approximately 300,000 kms per second - or in old measurements 186,000 miles per second.)
Cosmology has enabled early understanding and fundamental technologies, (and it contunues to do so), for example:
- Timepieces - from the first sundial to modern atomic clocks
- Navigation - early sailors used the stars to confirm their latitude and longitude
- Calendars - in early times denoting when to harvest crops before floods
- Optics and lenses - telescopes with better and clearer magnification, assisting the development of spectacles
Humanity's insatiable need to know what is 'out there' has more recently driven us beyond our own world.
Cosmology has inspired us to put humans on the moon (unless you believe it a gigantic hoax), to send probes to other planets in our Solar System, to fly past and investigate the gas giants (Saturn, Jupiter, Uranus and Neptune) and to go even beyond our own Solar System. (Voyagers 1 and 2 launched in 1977 - and currently as at 2008, Voyager is the farthest ever man-made object from the Sun).
The Universe is not the quiet, static, sedate place you might think it is.
In our own Galaxy (called the Milky Way since Chaucer's time, 1380, a while before the chocolate bar) and in all other galaxies, amidst massive turbulent gas clouds - stars and planets are being formed - and dying - sometimes with catastrophic effects.
Our own Sun has been identified as a third generation star, made up of the heavier elements blown-off from two previous stellar explosive 'deaths'.
Our Earth came into existence because of this universal evolution and one day (in around 7.6 billion years) it will die as our Sun expands beyond the orbit of Earth in its own death throes.
Long before then, the Earth will become uninhabitable.
Happily for us this is still about a billion years away - ample time for whatever form of life happens to reside here in the future to prepare an exit strategy..
The violent nature of the Cosmos can be seen clearly in the meteor impact craters on the surface of the moon - and on our own planet too, for example at Meteor Crater (also known as Barringer Crater) near Flagstaff in Arizona, USA. The crater is over a kilometre wide, and yet was made by a meteor only measuring about 50 metres.
There is also evidence to support the theory that a large meteorite striking the Earth some 65 million years ago could largely have been responsible for the extinction of the dinosaurs and almost all other life on Earth. The residual impact crater, (called the Chicxulub Crater), is 120 miles wide and a mile deep, now beneath Yucatan Peninsula, Mexico. This was caused by an asteroid of uncertain composition (called a bolide) at least six miles wide.
Huge flying rocks the size of a small country aren't the only danger - Cosmic radiation is strong enough to kill all living matter.
Life on Earth is able to exist because we are protected from this radiation by a fragile and frighteningly thin layer of atmosphere - which by all accounts we are doing our damndest to destroy.
Cosmology, like any expertise has its own language and theory, within which understanding a little physics is helpful for grasping the basics.
Cosmology encompasses astronomy, which is the science of studying 'heavenly bodies' or stars (astro is Greek for star).
Avoid confusing astronomy with astrology, which is the art of interpreting influence of stars and planets on humans, and while very real amd meaningful to some people is not a science as such.
Such basic understanding (and enthusiasm) is also useful if you wish to read Stephen Hawking's 'Brief History of Time' and his subsequent publication 'The Universe in a Nutshell'. Neither is an easy read although both are well worth the effort.
On a cloudless night - even without binoculars or a telescope - you can look up and see a glorious night sky.
This is better appreciated when you are away from city lights.
Stars and some of our Solar System planets are clearly visible.
During the late winter months (specifically January) the glorious constellation of Orion dominates the sky.
The planet Venus (referred to as the Evening Star and Morning Star, since early star gazers thought them two distinct planets) is the second brightest object in the night sky after the Moon.
Throughout time, poets and songwriters have alluded to the enigmatic beauty of the cosmos. So too have lovers everywhere.
Some people believe humanity has a relevant place in the Cosmos otherwise we wouldn't be here.
What that place is depends on your viewpoint and beliefs.
Some believe that our place has not yet been defined and may not be revealed to us, or discovered by us.
We are not insignificant, although we may feel that we are, against the vastness of space.
And for all this, humanity is still the only intelligent life within this Universe that we know exists.
Which is a staggering thought, whether we are at the centre of it or not.
This introductory explanation to Cosmology was written by Sandra MacCarthy, who has expertise in cosmology and writing. Her provision of this material is greatly appreciated.
Cosmology is a big subject in many respects. Perhaps the biggest subject of them all, since it covers the Universe.
Cosmology is included in this website because it relates in different ways to fundamental aspects of life and learning, especially to our own sense of purpose, perspective and relationships.
Life, and the day-to-day superficial pressures of work (and learning and teaching too) tend to distract us from deep and vital issues and opportunities.
Having a strong appreciation and awareness of the Universe helps keep us mindful of our place within it - in whatever way makes sense to you - and as importantly, so that we make the most of the time we have.
We are connected to our past, and more interestingly we are connected to our future. Everything we do has consequences. If only for ourselves, but more often for others too.
"No man is an island," wrote English poet John Donne. The fuller lines make more sense:
"No man is an island, entirely of itself; every man is a piece of the Continent, a part of the main; if a clod be washed away by the sea, Europe is the less, as well as if a promontory were, as well as if a manor of thy friends or thine own were; any man's death diminishes me, because I am involved with Mankind; and therefore never send to know for whom the bell tolls; it tolls for thee." (John Donne, 1572-1631, from Devitions Upon Emergent Occasions, Meditation XVII, written in 1624.)
Here is a helpful guide to reading A Brief History of Time - and here is the book itself
- Love and spirituality in work and business
- Transactional Analysis
- NLP (Neuro-Linguistic Programming)
- Adams' Equity Theory
- Personality Models and Types
- Howard Gardner's Multiple Intelligences Theory
- Kolb's Learning Styles
- McGregor's X-Y Theory
- McLelland's Motivational Theory
- Maslow's Hierarchy of Needs
- Kirkpatrick's Learning Evaluation Model
- Bloom's Taxonomy of Learning Domains (Educational Objectives)
© Sandra McCarthy and Alan Chapman 2008-2009.