The double-slit experiment, when conducted with larger particles like molecules, can still exhibit interference patterns despite the interactions between the atoms within the molecule. This phenomenon is known as wave-particle duality, a fundamental principle of quantum mechanics.
In the double-slit experiment, a beam of particles, such as electrons or molecules, is directed towards a barrier with two narrow slits. Beyond the barrier, a screen captures the pattern of particles that pass through the slits. Surprisingly, even when particles are sent through the slits one at a time, an interference pattern emerges on the screen, indicating wave-like behavior.
When a molecule passes through the double slits, its atoms are indeed interacting with each other. However, the important aspect to consider is that the molecule's wave function describes the probability distribution of finding the molecule in different positions. The wave function takes into account the various paths that the molecule can take, including going through both slits simultaneously.
The wave functions of the individual atoms within the molecule combine to form the overall wave function of the molecule. This collective wave function can interfere with itself, resulting in an interference pattern on the screen. The interaction between the atoms within the molecule does not disrupt this interference because the wave function accounts for all possible paths, including those involving interactions between the atoms.
It's important to note that the interference pattern becomes less pronounced as the complexity and size of the molecule increase. This is due to various factors such as decoherence, which refers to the loss of quantum coherence as a result of interactions with the environment.
In summary, in the double-slit experiment with molecules, the interactions between the atoms within the molecule do not ruin the interference pattern because the wave function of the molecule encompasses all possible paths, including those involving atomic interactions.