Two of the key ideas involved in quantum mechanics are wave particle duality and the Observer effect. These two ideas have changed the way that scientists think about the world.
Firstly, wave particle duality is the fact that every elementary particle exhibits the properties of both particles and waves. This idea started with Thomas Young’s 1803 double-slit experiment. With a ripple tank he showed how water waves interfere with each other, and then repeated that in the context of light as a wave. He still found the interference pattern. An interference pattern is the superposition, or overlapping, of two or more waves of the same or nearly the same frequency. Following this experiment, in 1922 de Broglie repeated this experiment, using electrons. When there were two slits, it was expected that the …show more content…
As previously mentioned, it is linked to wave particle duality, when the electron stopped behaving like a wave and behaved like a particle when being observed. Observation collapses the wave function, as if the electrons know they are being watched.
This links to Heisenberg’s Uncertainty Principle of 1927, which stated that you can know an electron’s position or velocity, but never both. This is because the act of observation means that once we find one out, we cannot find out the other one. Neils Bohr, who worked with Heisenberg on the Uncertainty Principle, found this conclusion very odd. He added “The observer and the observed are not two different things, they are both part of the whole”.
Bohr and Heisenberg had very different opinions on the effect of observation. Bohr concluded “Everything is real until it is observed”, whereas Heisenberg concluded quite the opposite; “Nothing is real until it is observed”. Although these contradict each other, they are ultimately making the same point: it is the act of observation which determines the