It is a common misconception. You can't falsify anything without your own theory. Some people just can't (at the conscious level) recognize their assumptions (if you don't see air, it doesn't mean there is none).
Hypotheses make predictions. Experimentation can test those predictions without providing an alternative explanation for the phenomena you are testing.
For example, if I came up with a theory of gravity that implied everything should fall towards the earth at the same speed, all you need to do to falsify my theory is show that this is not the case. You do not need to know that wind resistance is the confounding variable to know that the theory which suggests everything should fall at the same speed is wrong.
Again, you can’t make an experiment without an underlying theory.
I understand some concepts are so ingrained, that they are perceived as theories but as reality itself (Newtonian physics before the end of XIX century) but physics is not constrained by our intuition (what we are familiar with).
Could you provide an example? Because I did so, and you repeating exactly what you said earlier doesn't really invalidate mine. As far as I can tell, my example is valid and invalidates your theory that you need a theory to falsify another theory.
Hypotheses make predictions. Experimentation can test those predictions without providing an alternative explanation for the phenomena you are testing.
For example, if I came up with a theory of gravity that implied everything should fall towards the earth at the same speed, all you need to do to falsify my theory is show that this is not the case. You do not need to know that wind resistance is the confounding variable to know that the theory which suggests everything should fall at the same speed is wrong.