Chemistry+Applications+Essay+10

Chemistry Applications Essay

** __The Double Slit Experiment__  **


 * Is light a wave or a particle? This question has sparked a war among the chemistry and physics communities alike for generations. One of the first experiments in this field was the famous double slit experiment, performed by scientist Thomas Young in 1801.The experiment consisted of firing a light through a board with two parallel slits in the middle of the board, and observing the pattern that the light produces on the other side of the board. It was hypothesised that if light was made of particles, that the light would create two bright bands directly behind the slits, and that the sheet which the light was projected on would absorb the photons that passed through the slits. Once the experiment was performed, though, an interesting result was observed. The light seemed to create an alternating pattern of light and dark bands, also called an interference pattern. This type of pattern is only seen in nature when waves collide and interfere with each other. Young soon came to the conclusion that light must act as a wave, and a particle. **
 * This proposition was improved upon in a later version of the experiment, where an apparatus was added to the slit board to detect which slit the electrons shot in the place of light went through. The observation device saw the electrons go only through one slit, as a particle would, and two lines soon appeared on the result paper. After the camera was removed, interestingly enough, the electrons went back to acting as a wave would. It seems that the act of observation actually changed the outcome of the experiment. This breakthrough in quantum physics supports the controversial Schrodinger theory, which states that quantum particles can be in a state of superposition until they are forced to to collapse to a reality due to observation. A simple example of superposition is if someone is asked a yes or no question. Since they can choose one outcome or the other, they are in a superposition, and the need for the question to have an answer forces them to pick either yes or no. The state of superposition for the electrons in the experiment is that they can either go through the left or right slit. When the electrons are not observed, though, it is theorized that they both go through the left slit, and the right slit, which causes them to interfere with each other, and creates an interference pattern. Once they are observed, the electrons collapse to a reality and simply go through one slit or the other. **
 * Why does this all matter though? The answer is strikingly simple. The world of newtonian physics and basic chemistry is long past, and newly discovered subatomic particles abide by a different set of rules than classical, observable objects. In short, all of what we used to know has gone out the window when quantum particles are examined, and Young’s double slit experiment is the first step in trying to understand this strange new world. The test has also opened up new ways of thinking about our universe, as well as contributing to the widely accepted “Wave- Particle Duality” theory, which categorizes light as a small packet of waves that can act as a particle at some times and a wave at others. Plus, the test proves once and for all that the act of observing an experiment can in fact change its outcome, which is still an eerie and unexplained occurrence in the science community today. Still, little is known about the strange behaviors of quantum particles, and this experiment was only the beginning of a new era of physics and chemistry. **

** Works Cited  **
 * "Double-slit Experiment." Wikipedia. Wikimedia Foundation, 01 Feb. 2013. Web. 04 Jan. 2013. **


 * "Two-Slit Experiments." Two-Slit Experiments. N.p., n.d. Web. 04 Jan. 2013. **