[nkrisc]

“Real” in the sense it exists within your mind, which exists (somehow) within your brain, which is itself likely real. So your imagination must have some physical basis, but it would exist entirely within your brain (or body, to the extent the rest of your body influences the brain itself).

Your brain imagining a specter in a doorway does not mean there is any anomaly within the physical space of the doorway at all that anyone else could perceive or measure - they would need to measure your brain to (theoretically) detect the physical basis of it.

What you see, feel, hear, taste is an interpretation of your physical environment, and may not accurately reflect it at all times.

[mensetmanusman]

Are fields physical in your explanation?

[nkrisc]

Fields and their influence on matter can be detected and measured, and even perceived directly by humans. So, yes.

[danparsonson]

Fields are absolutely physical - physical contact is due to the interaction of electromagnetic fields, for example.

[mensetmanusman]

It’s interesting, because there are textbooks that say the magnetic field lines aren’t real, but are a good visual of what happens when a magnetic particle is there…

[danparsonson]

Yes field lines are just an indicator of where the field is - a bit like how maps have contours showing height above sea level; those contours aren't physical things but they describe the physical environment in a schematic way.