• If a laser beam passes through two slits and is observed through a camera, then an interference pattern will be detected on the screen, because the light will behave as a wave.
• If we lower the brightness of the laser really low, we should be able to see each individual photon, because there won't be such a massive stream of photons coming from the laser, proving that light behaves as a particle as well.

We had a long Interview with prophessors Micheal Potter and David Feder at the University of Calgary.

https://www.popularmechanics.com/science/a22280/double-slit-experiment-even-weirder/ popular machanics. 

Manipulated variable: voltage of the light

Responding Variable: The light pattern was an interference and the light was more faint to the sides of the pattern.

Controlled Variable: space between the slits and the slits itself              

Setup:

• 3D print a base for the slits, laser and camera.
• Connect the collimator to the laser and connect the laser to a compact laser diode driver.
• Add slits to the 3D printed base with tweezers to not mess up the slits
• Add camera to the base and connect camera to laptop
• Add the compact laser diode driver and the 3d printed base to a wooden board.
• Use soldering and wiring to connect all the things that need wiring for.

Execution:

• Turn on TEC (Thermoelectric Cooling) to not overheat the laser
• Power on the laser.
• Look at the camera through the laptop to see the light because it barely visible with the human eye
• Lower the brightness of the laser down and observe each photon.
• Analyze the data on both the experiments

We observed an interference pattern as a result of the laser passing through the two slits.

As a result of observing the interference pattern , we can see that the photons are acting like waves, interfering with eachother in turn creating an interference pattern.

We wanted to find out if light behaves as a wave or a particle.Based on our research we created our hypothesis, If a laser beam passes through two slits and is observed through a camera, then an interference pattern will be detected on the screen, because the light will behave as a wave.If we lower the brightness of the laser really low, we should be able to see each individual photon, because there won't be such a massive stream of photons coming from the laser, proving that light behaves as a particle as well.Our hypothesis was correct, because an interference pattern occurred after the laser passed through the two slits, but we were still able to prove that if we would have turned the light down a lot we would've been able to see each individual photon hit the camera/screen and if we took that and looked at it over a period of time we would see 2 peaks. This proves that our hypothesis was correct and that light behaves as a wave and a particle.

The double-slit experiment helped scientists discover the strange rules of quantum mechanics, which has led to amazing technologies we use today, including lasers, and barcode scanners. Barcode scanners use the property of the interference pattern to read the barcode. This experiment has also been a starting point to the development of quantum computing. Quantum computing runs on the entanglement of qubits (things that can exist as multiple states at once\ superposition). An example of this could be photons, they can exist as a wave and a particle at the same time. The entanglement of qubits means that if multiple qubits entangle, then the state of one qubit affects the state of all of them. The act of entanglement allows quantum computers to complete problems much faster than regular computers.

At the start of our experiment we came to the conclusion that are slits were to big and too far apart for it to show an interface pattern, so to fix this we ordered slits of thorlabs for the experiment but then we found out that those slits are too small for a photodetector to be placed in front of them and detect which slit the photons pass through. Then later on in our experiment we met with professors from the University of Calgary and they told us that the laser we use produces a large stream of many photons passing through each slit constantly so we don't have the ability to send just a few, or one photon through the slits.

wikimedia commons https://commons.wikimedia.org/wiki/File:Two-Slit_Experiment_Light.svg - Feb 1, 2025

Micheal Potter, David Feder - Mar 7, 2025

popular machanics https://www.popularmechanics.com/science/a22280/double-slit-experiment-even-weirder/ - Mar 2, 2025

THORLABS https://www.thorlabs.com/ - Feb 3

We want to acknowledge: Prophessors David Feder, and Micheqal Potter for having a meeting with us and broadening our understanding towards this experiment and quatum mechanics, Yoni Datner for supplying us with all of our materials for this project, Micah Libin for his support and setting up our meeting with the prophesors, and Evan Gelman for helping us get started and set up and conduct our research.