debunking a theory
The phrase 'echar por tierra una teoría' in Spanish translates to 'to debunk a theory' in English. This typically means to disprove or discredit a theory that was previously believed or accepted. This phrase is metaphorical and used in context when a person or set of data proves an accepted idea or belief to be false or incorrect.
The professor knew how to debunk a theory that had stood for centuries.
The professor has been successful in disproving a theory that has been established for a long period of time, which unveils a new point of view or understanding, hence 'echar por tierra una teoría'.
To debunk a theory, you need to present strong counter-evidence.
One would need to provide substantial and solid evidence against an established theory in order to refute or 'debunk' it; as is implied in the usage of 'echar por tierra una teoría'.
Many scientists tried to debunk a theory but could not overcome the evidence.
Despite many scientists' efforts to disprove a specific theory, they could not stand against the existing evidence supporting it. Thus, they failed to 'echar por tierra una teoría'.