This theory is unlike most scientific theories as there isn’t a particular scientist responsible for it. Instead, many scientists have contributed over a long period of time, providing theories and evidence for the Big Bang theory to evolve from.
Evidence
There are four pieces of evidence to support the Big Bang theory, although neither is a proof of the event, because scientific theories aren’t ever proven.
EVIDENCE ONE
It is almost certain that the universe had a beginning.
EVIDENCE TWO
Galaxies seem to be moving away from Earth according to their distance. This fact supports the part of the theory that says the universe is expanding. Galaxies further away from Earth are moving at a faster rate. It is like blowing up a balloon. If you mark five points in a line with equal intervals between them, as you blow the balloon up, the distance between the points increases.
EVIDENCE THREE
If the universe was very hot when the Big Bang occurred, there should be some remains of the immense heat. Scientists have found these remains in the form of Cosmic Background Radiation (CBR). CBR is microwave radiation that has been found to fill the entire universe. CBR is assumed to be the same radiation that was produced when the universe was still young, after the singularity.
EVIDENCE FOUR
There is a large amount of Hydrogen and Helium in the universe, which backs up the idea that Hydrogen and Helium formed within the first three minutes of the Big Bang.
The Development and Progression of the Big Bang Theory
1791 Erasmus Darwin
Described a universe that contracts and expands in a repeated way.
1826 Heinrich Wilhelm Olbers
Stated that in a static infinite universe the night sky should be bright, but the sky as we see it is dark, and so, the universe must be finite and non-static.
1848 Edgar Allen Poe
Suggested that the universe began as a single ‘primal’ particle and expanded from a force that he called ‘divine volition’, one of the two forces that makes up all matter (repulsion and attraction). He believed that the universe would be drawn together by gravity to repeat the repulsion and then, attraction.
1910s Vesto Slipher and later Carl Wilhelm Wirtz
Observed that spiral nebulae were moving away form Earth. Wirtz also observed a redshift in nebulae
Albert Einstein
His theory of General Relativity admitted that the universe couldn’t posssibly be static.
1927 Georges Lemaitre
Suggested that the universe began as a single atom of energy that was hot and dense. The atom exploded, which caused space to expand outward.
1929 Edwin Hubble & Milton Humason
Edwin Hubble discovered that multiple galaxies existed, and that therefore the Milky Way wasn’t the entire universe (as was believed at that time). He aso managed to measure the distance to other galaxies, and estimated the scale of the universe.
Hubble and Milton Humason (his assistant) discovered that other galaxies were moving away from the Milky Way.
1940s George Gamow
Developed Lemaitre’s Big Bang theory based on the suggestion made by Hubble that the universe is expanding.
Fred Hoyle
Suggested that as the universe expanded, new matter would be created.
1960s Stephen Hawking
Ruled out the idea that the universe would infinitely expand and contract, and thus the universe must be finite.
1965 Arno.A.Penzias & Robert W Wilson
Discovered a low level of background ‘noise’ whilst testing a horn antenna, that was designed to detect microwave radiation. The radiation the antenna picked up is thought to be Cosmic Background Radiation, left over from the Big Bang, and can supposedly be found anywhere in the universe.
Before the Big Bang
There is still no scientifically backed theory concerning what caused the Big Bang (if it really did occur). Some argue that it was God who created the universe, and so he caused the Big Bang.
Scientists would say that before the Big Bang was the singularity, which as described before, is a point where no time, space, matter and energy exists. But surely it must be something? What caused the singularity?
To date there is no scientific theory to suggest the answers to these questions, but scientists are looking for answers.
Apocalypse
The beginning of the world has fascinated the human race, but not many ponder on the end of the universe; whether there will be an end, and what will happen if there will (or won’t)?
Erasmus Darwin, Edgar Allen Poe, and Stephen Hawking suggested that there won’t be an ‘end’ to the universe as such; it will carry on expanding and contracting infinitely.
The Big Crunch is a corresponding theory to the Big Bang, and states that the universe will collapse into itself, back into the singularity, after the expansion of the universe. But this depends on whether the universe is finite or not, if the universe is infinite, and the expansion doesn’t ever stop, then there can’t possibly be a Big Crunch. The theory doesn’t say anything about re-expansion, so what will happen after the contraction is another mystery.
Another theory that corresponds to the Big Bang theory is the Heat Death. This theory says that there will be a point in time when energy stops flowing from places of high concentration (of energy) to places of low concentration, since all energy is equally spread across the universe.
Flaws in the Big Bang Theory
- A redshift effect can occur if light is slowed down due to gravitational pull from masses around it.
- There is no explanation as to what might’ve caused the Big Bang.
- Two galaxies have been found to be moving towards each other, almost colliding. This proves the expansion of the universe wrong, because if it was truly expanding, galaxies would be moving further away from each other, not closer.
- Cosmic background radiation could easily be radiation from other bodies in the cosmos, the radiation measurement of CBR fits the expected level from other galaxies.
- If space really is expanding, we should be able to observe the expansion of distant galaxies too, not just those near us.
- The theory contradicts many religious beliefs, which many people strongly believe are true.
Evidence
There are currently four pieces of evidence to support the Big Bang theory, although neither is a proof of the event, because scientific theories aren’t ever proven.
EVIDENCE ONE
It is almost certain that the universe had a beginning.
EVIDENCE TWO
Galaxies seem to be moving away from Earth according to their distance. This fact supports the part of the theory that says the universe is expanding. Galaxies further away from Earth are moving at a faster rate. It is like blowing up a balloon. If you mark five points in a line with equal intervals between them, as you blow the balloon up, the distance between the points increases.
EVIDENCE THREE
If the universe was very hot when the Big Bang occurred, there should be some remains of the immense heat. Scientists have found these remains in the form of Cosmic Background Radiation (CBR). CBR is microwave radiation that has been found to fill the entire universe.
EVIDENCE FOUR
There is a large amount of Hydrogen and Helium in the universe, which supports the idea that Hydrogen and helium formed within the first three minutes of the Big Bang.
What does it all mean?
If the Big Bang theory is correct, it could help scientists in finding out more about the universe, perhaps leading to ventures such as space exploration, finding extra terrestrial life, time travel. If it were certain that the big Bang theory is correct, scientists would find it easier to hypothesise and predict the future of the earth, solar system, galaxy, universe etc.
Some believe it is possible that understanding more about the beginning of the universe and exactly where we came from might take them closer to God, or maybe even help to prove the existence of God to others.
However, there is always a chance of another theory developing against the Big Bang theory. It may be the most widely accepted theory today, but that does not mean anything against actual proof (or disproof), reasonable arguments against the theory do exist, as described earlier.
In my opinion, it would be wrong to accept this theory as the absolute truth because I think the only way to find out if it is true is to actually witness the event, for which to happen, we would have to wait for science to advance into time travel (if such a thing ever happens)!.
Bibliography & Evaluation
Books
Dictionary of Science & Technology by Simon Collin (pg 57)
A Short History of Nearly Everything By Bill Bryson (pages 9, 10)
Websites
- http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation
- http://en.wikipedia.org/wiki/Graphical_timeline_of_the_Big_Bang
- http://en.wikipedia.org/wiki/Big_Crunch
- http://en.wikipedia.org/wiki/Big_bang
- http://en.wikipedia.org/wiki/History_of_the_Big_Bang_theory
- http://en.wikipedia.org/wiki/Planck_epoch
I used a lot of information from Wikipedia (- an online encyclopaedia containing information that is open for anyone to edit). This makes its information a lot less reliable, because if a person who doesn’t know much about the topic, or has a false understanding of a topic, the information you receive could be incorrect. There are also a lot of controversial subjects and topics portrayed on Wikipedia, meaning people who disagree edit the information according to their own beliefs and opinions, therefore, information could be biased. However, Wikipedia has various procedures in place to correct incorrect information and delete biased information - there are approx. 13,000 volunteer contributors, who edit information and remove false/bias claims from the articles.
- http://map.gsfc.nasa.gov/m_uni/uni_101bb1.html
- http://www.nasa.gov/home/hqnews/1995/95-87.txt
- http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level2/cosmology.html
These websites belong to NASA, the aeronautics and space administration national to the USA.
I used this source to find out about possible flaws in the Big Bang theory. However, the purpose of that article was to dissuade people from believing the Big Bang theory. Some of the comments and statements were biased, and the content boldly suggested that any concept that is not in sync with biblical teachings is false. There were a lot of misconceptions about what the Big Bang theory actually says. For example: “The expanding space idea suggests that the Big Bang was not a gigantic explosion but was instead an expansion of space.” This implies that the Big Bang theory was a gigantic explosion, when various sourcesclearly state that this is not the case, and that the original theory is that space expanded, not that the singularity ‘exploded’. Such inaccuracies are included throughout the article, but I used the information that was relevant, and chose reasonable arguments against the theory. Most of the information from here wasn’t very reliable, though there were a few good points.
- http://www.virtualsciencefair.org/2004/khak4a0/public_html/problems.html
- http://www.rense.com/general53/bbng.htm
- http://www.big-bang-theory.com/
- http://www.telescopes-astronomy.com.au/telescopes039.htm
- http://www.biblelife.org/bigbang.htm
The Penguin Dictionary of Science (by various authors, ISBN: 0-141-01074-6) includes this under the definition of ‘Big Bang’: “…the Universe was born in a rapid expansion from a condition of ultra-high density. http://map.gsfc.nasa.gov/m_uni/uni_101bb1.html (NASA) says: “. . . 12 to 14 billion years ago, the portion of the universe we can see today was only a few millimetres across. It has since expanded from this hot dense state. . .