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Name:  Aaron R.T.
Status:  student
Age:  14
Location: N/A
Country: N/A
Date: 2000-2001

Would you please explain what amplitude is in quantum physics.


In quantum physics, particles are not described as being in one place at one time. We use items known as wave functions to describe particles. Research shows that knowing where a particle is at one moment does not mean we can know where it is one second later. Also, measuring where something is will usually make it move. To talk about a real particle, we can only say where it is likely to be. We can only say how it is likely to be moving. Most of quantum physics is based on probability.

The "wave function" of a particle provides a way to combine all these probabilities into one function. The mathematics is easier to deal with if we can use trigonometric functions. The amplitude is the value of the wave function at a certain position and time. The square of that amplitude corresponds to how likely the particle is to exist at that position and that time. Where the amplitude is largest is where the particle is most likely to be at a certain time.

Dr. Ken Mellendorf

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