I came across a quote. It sounds like that. We cannot find the evidence of non-existence of a particle. We just did not find any evidence of it's existence.
The interesting point is how we can prove something does not exist. It cannot exist or it does exist but behave as nothing. Is it possible?
How can we determine what existence is? What makes something evidence? What is the condition? Martin Heidegger had studied "existence" thoroughly. In his book "Being and Time", he talked about the criteria and properties of being of everything. He tried to compare being and not-being in a conceptual way. It was incredible in 1927 because not many philosophers would think about it deeply.
Evidence is normally an observable event which has connection with our subject. When we expect such subject does not exist, nothing would interact with it. No connection can be made in our universe. Thus no evidence of non-existence can be provided. Therefore, we cannot find the evidence of non-existence of a particle.
