The phrase "a concrete proof" is correct and usable in written English.
It can be used when referring to a specific, tangible piece of evidence that supports a claim or argument.
Example: "The scientist presented a concrete proof of her theory through extensive experimentation and data analysis."
Alternatives: "a solid piece of evidence" or "a definitive proof".
In other words, we have, by hypothesis, a concrete proof of A at hand.
A concrete proof of this result is similar to that of[15, pp. 311 313].
The presence of different organisms since the Earth existed is a concrete proof for evolution.
The demonstration proceeds with a generalisation over all numbers k which number the axioms in a concrete proof and then performs a sequence of selections on them.
Likewise in Weir's version of game formalism, what makes true (or false) "sin2θ + cos2θ = 1" in a particular system is the existence of a concrete proof or refutation, though the statement that such a concrete proof exists is no part of the literal meaning or sense of the claim.
Andreoli originally discovered focalization as a concrete proof search strategy in proof theory of linear logic, putting to the foreground the role of polarity in logic.
"We've never seen any concrete proof that we are children of the disappeared..
Yet, we prefer here to present the ideas to build a more concrete proof, following for instance what is done in Chapter 8 of [84].
A demonstration or concrete proof of the antecedent, be it an actual or a hypothetical one, is required to obtain a canonical form.
Though Anglo-French-Israeli collusion was widely suspected, all three governments lied about the matter and there was a shortage of concrete proof (though the Times had by now been let into a secret so closely guarded that Eden tried to persuade the French and Israeli governments to destroy their written agreements).
This measurement offers, for the first time, a direct and concrete proof of correct in situ synthesis of RNA microarrays.
