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In current quantum models, name one or more objects that collapse an entangled waveform into a single classical particle other than a complete living human person. The "duplicate" I just read has an accepted negative score answer that starts with "An observer is a person...", so I don't know how to make this simpler. If you are interested in jokes related to the issue, continue reading, but otherwise you may begin formulating an answer now.
Here are some examples of solid answers that, while not true, would answer my question if they were in a modern quantum model:
Anyone with a full head of hair is an observer. Receding hairlines have a reduced probability of collapse. Wigs count too.
Anything with a phone number is an observer; it doesn't matter to the quantum state if anyone picks up. The classical result and its delta T depends on your carrier, and all possible states use the data plan simultaneously.
Anything that walks on two legs is an observer. Sorry dolphins. And you can't just do it sometimes, it has to be your primary mode of transport, so no weasling your way in, dogs.
It doesn't quantize until it's published in Nature. PNAS doesn't work, and we all know the news can be both true and false simultaneously now.
God (not yours, the other one) decided that some things should act classical, and entangled quantum stuff is so impressed with the endorsement when they come into contact, it acts like a classical thing from that point forward.
The electron over there on your keyboard and/or phone is actually the one and only observer. Its potential paths look like observers now, but as soon as you touch it, we all disappear.
Include as much math as it takes. A greek letter with a hat that does the job is fine. Just no humans in your theory. Like teaching it to a millenial, one might say.
There may be follow up questions, but it is not necessary to answer them to my satisfaction to receive check mark.