In physics they have the concepts of dark energy and dark matter. These two things have never been seen in the lab and/or in any particle accelerator to know if they are real or imaginary. Thus the names, dark matter and dark energy. We are still in the dark with respect to direct lab evidence.
These things are inferred from observations that cannot be directly explain using only existing standard theory. The concepts of dark matter and energy were not always needed. But as science tools became better, the standard theory could not keep up with the anomalies and needed an addendum to maintain the status quo. This addendum was added, but it still has not been directly proven in the lab to be real. It is sort of place holder that is spoken of as though already proven. This is a prestige magic trick for the masses and the money changers.
Dark energy is similar to postulating that the God, Helios, by riding his chariot ,was responsible for the movement of the sun. This was inferred at a time when the then standard theory, had no good physical explanation for the movement of the sun. Helios was inferred by observation, in light of the then standard theory, even though he can't seen in the lab. He is also too far away.
God can be proven using the same schema that is considered allowable by physics. We can infer God by the mere existence of observational reality, since no theory can yet create our universe from scratch, in a logical fashion. Like Dark energy we still sort of need this placeholder to correlate the deeper questions. If anything physics and science is starting to copy the religion schema of proving concepts via inference, that are elusive in the lab.