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What is a Wave Function? - What Does a Wave Function Collapse Mean?

 

Atom and subatomic particles show both wave and particle properties. To understand their dual nature, we need equations, that explain their behavior, as in classical physics. In classical physics, we use Newtonian equations to understand properties such as positions, velocities, forces, and energies of massive objects in the macro world.

Understanding such fundamentals is important as we enter the quantum world. When we step into quantum physics, we meet the Schrodinger Equation, which is the equation of motion established by analogy in classical physics. The main thing in this well-established equation is the wave function. The wave function is represented by the Greek letter psi (Ψ). This letter, which you see in the equation below, carries all the information about the particles in the system we are considering. Knowing it means knowing our particle. Let's examine the wave function in depth.

Expression of the Schrodinger equation.

In our previous articles, I talked about the concept of superposition. To briefly mention it again, superposition is the superposition of all possible states of the particle. It is the wave function that contains all these possibilities, that is, the thing that carries the superposition. Don't be confused by the wave expression in its name. It does not represent a real physical wave. It is called a wave function, in other words, a state function, because it includes all possible states, just like the overlapping of water waves.

If we solve the wave function in the Schrodinger equation, we get information about the position, velocity, momentum, and energy of our particle. Another important expression in the wave function is the concept of collapse.

What Does Wave Function Collapse Mean?
 
Let us explain this phenomenon through a simple example. Let's take an electron. Our electron has a spin, and we want to determine the direction of that spin. Theoretically speaking, quantum physics tells us that all aspects of this electron's spin exist in the same month with probabilities, and it carries it like a closed box in the electron's wave function. What we need to do is to measure the wave function of our electron, that is, to reduce it from all possible states to a single concrete value by making an observation. Thanks to this measurement, we collapse the wave function by making the spin of our electron show a single geometric direction. It is to reduce from multiple overlapping possibilities to one possibility.

This concept is very important. Because that's how we can understand and manipulate quantum particles. Thus, quantum computers, algorithms, sensors, etc. We make applications in technologies.

There is more information we need to understand.

Stay informed. :)



Reference

https://en.wikipedia.org/wiki/Wave_function

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