Introduction: The Double-Slit Experiment

In this post I will demonstrate the mechanics of particles and waves at the quantum, or the smallest of all possible states, level. To understand this experiment we must first understand how particles, or little balls of matter, act. If we randomly shoot a small object, say a marble, at a screen with a small slit in the middle we would see a pattern on the back wall where they went through the slit and hit the back wall:

Now, if we add a second slit we would expect to see a second band duplicated to the right, like so:

Now, let's look at waves using a single-slit screen. The waves hit the slit and radiate out, striking the back wall with the most intensity directly in-line with the slit. The line of rightness, on the back screen, shows that intensity. This is similar to the line the marbles make:

But, when we add the second slit, something different happens. If the top of one wave meets the bottom of another wave, they cancel each other out. Places where the two tops meet are the highest intensity, the bright, white lines on the back wall, and places where a top and a bottom meet are the lowest intensity, the dark, black lines in between. So now, there is an interference pattern on the back wall:

So when we throw "things", or matter, through two slits we get this, two bands of hits:

And with waves, we get an interference pattern of many bands:

Good, so far. Now, let's go quantum:

 An electron is a tiny, tiny bit of matter; like a tiny marble. Let's fire a stream through one slit. It behaves just like the marble, a single band of hits appears:

So, if we shoot these tiny bits of matter through two slits we should get, like the marbles, two bands of hits:

But we didn't... Instead we got an interference pattern. We fired electrons, tiny bits of matter, through. But we get a pattern like waves, not like little marbles. How? How could pieces of matter create an interference pattern like waves? It doesn't make sense. But physicists are clever, they thought maybe those little balls of electrons are bouncing off of each other and creating that pattern. So, they decide to shoot electrons through one at a time. There is no possible way they could interfere with each other:

 But after an hour of this, the same interference pattern is seen to emerge:

The conclusion is inescapable. The single electron leaves as a particle:

Becomes a wave of potential energy:

Goes through both slits:

And interferes with itself, hitting the back of the wall like a particle:

But, mathematically, this is even stranger! The electron exhibits properties of going through both slits, going through neither slits, going through just one slit, and going just through the other slit. All of the possibilities existed in "superposition", or all at same time in every possible way, with each other:

However, physicists were completely baffled by this. So, they decided to peek and see which slit the electron actually goes through. They put a measuring device, a gamma ray measurement filter, by one slit to see which one the electron went through:

But the quantum world is far more mysterious than they imagined. When observed, the electron went back to behaving like a marble. It produced a pattern of two bands, like matter would, and not an interference pattern, like a wave:

The very act of measuring, or observing, which slit the single electron went through meant it only went though one, not both. The electron "decided" to act differently, as if it were aware it was being watched. And it was there, that physicists stepped forever into the strange, "never-world" of quantum events. What is matter, particles or waves? And what does measuring, or observing, have anything to do with this? The observer collapsed the wave function simply by observing.







So, why did I post this quantum experiment as a part of my introduction? Simply because I feel that my life, and the life of every person, is terrifyingly in tune with the observations made by it: That when we are watched or observed by others, we behave much more differently than when we are alone. Also, we all may seem to be a certain way on the outside, but, upon further inspection, we are all, much like the universe, far more stranger and grander than any person could have imagined.

My name is Tyler Chalker, I am twenty years old and am attending my first year at Nevada State College. I have graduated from CSN with my AA in Secondary Education and I plan to get my Bachelors here at NSC within the coming years. I have always had a passion about educating others but that is not the main reason that I decided to teach, the biggest reason was the opportunity presented by STEP-UP to pay for the majority of my college. My time in college thus far seems no different than high school except that teachers are less empathetic and there are far less opportunities for social experiences. I remain hopeful, however, that this view will change during my time at NSC.

My hobbies include video gaming and reading. The video games that take up the majority of my time are World of Warcraft, Team Fortress 2, Call of Duty, and Monday Night Combat. Also, my favorite book is Tortilla Flat by John Steinbeck. It is a small novel about the lives of poor Americans of Spanish descent during the early 1920's who make up their lack of money with an outpouring of romantic and chivalrous actions.

As far as my interests go, I very much enjoy reading books on the topic of philosophy, cosmology, astronomy, and religion. I have read the Bible three times in my life and have committed a fair bit of it to memory. I have also read the Quran, the Book of Mormon, and am currently attending a synagogue to listen to the Talmud. My musical interests are not too specific, I would describe it as eclectic. I enjoy rock, hip hop, classical, metal, techno, and jazz. While my favorite composers, artists, and bands are Tchaikovsky, Mahler, Incubus, Binary Star, Sibelius, Talib Kweli, The Sound Providers, SLik d, Streetlight Manifesto, Gorillaz, Itzhak Perlman, Lupe Fiasco, Black Star, Reel Big Fish, and many more I won't mention for the sake of brevity.

In summation, I would describe my personality as being extremely calm but easily embarrassed. Open, understanding, affectionate, and curious. I have a sense of humor made of steel; it is very, very hard to offend me and it seems that I often make light of situations that are considered sensitive (I am told I need to work on this). Other than that, I am very quiet when it comes to instruction time and infinitely patient. I look forward to this course and learning from our esteemed professor Morgan and I hope to continue on with my place as a student even when I become a full-fledged teacher.









sources used: 
http://www.youtube.com/watch?v=DfPeprQ7oGc
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