Helithos
Posts: 2
Joined: Thu May 07, 2020 6:30 am

### Thought Experiment: Quantum mechanics and the double slit experiment

Please, correct me if my understanding of this concept is not correct. Below is how I understand it currently.

I have a question about probability waves collapsing and behaving like particles when measured during the double slit experiment. Theoretically, our macro world could behave in a similar way. For example, a tennis ball could behave like a photon if the tennis ball is "informationally isolated" from the universe. This means that there is no record made anywhere in the universe of which path the tennis ball follows ( I.E. removing all air particles, cooling the object to absolute 0 and considering the gravitational waves being emitted from the tennis ball and elsewhere).

So I understand that it is not possible to cool something to absolute zero (or at least not yet possible) and it isn't possible to make a 100% vacuum (from my understanding at least).

HERE'S THE QUESTION:
If we could replicate the necessary circumstances (absolute zero, 100% vacuum, etc.), do you think we could we drop a tennis ball into that environment and see the theorized result of the tennis ball being super positioned? Just a fun thing to think about. I really just want to know your thoughts on this subject. Thanks!

VIDEO TITLE: Why don't quantum effects occur in large objects? double slit experiment with tennis balls

charlesg
Expert
Posts: 37
Joined: Thu Apr 18, 2019 7:51 am

### Re: Thought Experiment: Quantum mechanics and the double slit experiment

Hi Helithos,

This is an interesting thought experiment indeed.

I understand that you're asking about the double-slit experiment showing the wave-particle duality nature of light. A 1999 research article (https://www.nature.com/articles/44348) generalized the wave-particle duality experiment to C60-fullerenes, which have a mass of about 720 u. In theory, it does seem that this could generalize to larger objects.

Since you're asking whether we could "see the theorized result," the answer is unfortunately no (for now). For particles larger than a neutron, the wavelength is extremely short, so it is difficult to observe the wave characteristics (such as diffraction) of something as large as a tennis ball. Another way of looking at this is that, as a large object, the probability distribution of the tennis ball is extremely narrow. It is so highly unlikely to be outside its observed position that it is difficult (or impossible) to demonstrate its wave nature at that scale.

Hope that helps. Others should feel free to jump in with any thoughts.

Best,
Charles

Helithos
Posts: 2
Joined: Thu May 07, 2020 6:30 am