Have you ever heard of Werner Heisenberg? Most people haven’t, which is quite astonishing considering that he created one of the most popular principle in quantum physics, the Heisenberg Uncertainty Principle.

The Uncertainty Principle is a theory instituted within quantum mechanics and states that the exact position and the exact speed (velocity) of an object can never be simultaneously known. The origin behind this theory lies in the fact that every object and being in the universe exists as both a particle and a wave separately. Therefore waves that you see in the ocean are indeed made up of smaller waves, which is quite ironic.

In quantum mechanics a wave and particle are two very different things. A particle for instance is present at a specific point, and does not move. You can think of it as the exact location you are at, and the exact location you are traveling to when using a GPS. A wave on the other hand can exist at many different points since it fluctuates and oscillates, but unlike a particle a wave has what is referred to in quantum physics as momentum. You can think of this as the many different routes shown on a GPS that you can take to your destination from your current location. Momentum is calculated by multiplying the mass of an object by its velocity, and is related to the wavelength of a wave. A fast (velocity) moving object has a short wavelength and a lot of momentum compared to a slow (velocity) moving object that will have a longer wavelength and less momentum; a heavy object has a lot of momentum and therefore a shorter wavelength. This is why we do not measure the wavelength of every day objects, their wavelengths are too small to detect; however atoms are incredibly small and emit wavelengths that are long and detectable and therefore we are then able to measure the wavelength and then calculate their momentum.

A wave has no position since it is constantly fluctuating and moving, and a particle has no speed since it is constantly at a specific point. In order to get both position and speed, scientists combine multiple wavelengths that are possible for a singular object in a section of possible positions and thereby multiple momenta (plural of momentum). When this occurs the certainty of position and speed are lost, because rather than having a specific position we now have multiple possible positions and rather than having one velocity we now have multiple velocities layered upon one another, which is why the Heisenberg Uncertainty Principle exists.

If you wanted to have certainty in position, you could add more possible waves (momentum) and thereby have more certainty in position but less in the velocity of the object, and if you wished to have more certainty in velocity, you could reduce the amount of waves being measured and increase the number of positions being measured from; however you would be unable to have both certainty in both velocity (momentum) and position of an object.