To view the behavior of atomic-scale objects explained through quantum mechanics is hard to grasp, even for physicists. Understanding energy and matter through wave particle duality and the uncertainty principle are ways to understand this as it is simply broken down. To do this, physicists had conducted experiments to share this understanding as well as understand it themselves.
In 1927 Heisenberg had come up with the uncertainty principle. He studied the electron under the microscope. Then when he exposed it to the photon it changed. Once the photon hits the electron it changes the electrons momentum. He determined that if the position is accurately known, then the momentum cannot be, and vice versa. Although important, this discovery was irrelevant to him because he thought the aim of physics was to describe what can be observed and not what could be there. So observing the location as well as the momentum is what physicists have been trying to do for many years.
Finding the location of a particle is related to the wave associated with the particle. The larger the amplification of the wave, the more likely it could be found within the proportionate square of the amplitude of the wave. It is understood simply through the marble split experiment that physicists had created and worked on.
Particles are matter, but in this case particles are marbles. If one is to continuously shoot hundreds of marbles through a slit in a wall, the wall behind it would have created a band of welts from the marbles in the same shape of the slit. Now place two slits in the first wall. It is obvious that after shooting these marbles a second time, they go through both slits creating two bands on the wall behind it.
Now think of a wave going through just one of the slits in the wall. The wave radiates out striking the wall with the most intensity in line with the band of the marble welts. Add a second slit to the wall and send a wave through both of the slits. This time, one wave meets the bottom of another wave and they cancel each other out, creating an “interference pattern” on the wall where the most intensity creates many bands in a pattern. When matter is shot through two slits, it makes two bands of welts and waves create an interference with many bands.
An electron is a very small particle, or small matter. Shoot electrons through one slit this time. It creates one single band just like the marbles did. Now shoot electrons through two slits. This will create an interference pattern, like the waves did. This had baffled physicists, so they tried again but shooting only one at a time thinking the particles were bouncing off each. Again this creates the interference pattern.
The possibilities were that one particle could go through one slit or the other, or through both, or through none. At this moment, a measuring device was placed in front of the slits to determine which slits the particles would shoot through. After shooting the particles, something different had happened. The particles produced two bands like the marbles did. What is matter? Marbles or waves? It seems as though the observer collapsed the wave function just by observing. Quantum mechanics may try to view the behavior of atomic-scale objects, but the possibilities of different behaviors are endless.
Another way to understand a small piece of quantum mechanics and the behavior of matter, is to say that you have a box and in this box is a glove. This glove could be either a left-handed glove or a right-handed glove. Checking inside only reveals what nature already knew. Imagine the glove is a quantum glove. It could either be left or right. Nature does not know. Until it is observed the glove does not exist, or it could be in between left or right, or it could be both. Nature does not know. Once it is observed, it will be decided.
Wave particle duality is a fundamental property of the universe and understanding this concept of multiple possibilities is mind-blowing. The universe is run on chance. The uncertainty principle in quantum mechanics is the understanding that the future behavior of atomic-scale objects is unknown. At the atomic level the theory states that there is a limit to what one can know about what goes on in nature. Nothing is certain.
By Brittany Varner-Miller