Copyright does not protect names, titles or short phrases at all. While it might be ethical to obtain the permission of the family of this professor, they could not successfully bring a copyright suit because of such use.
Personality Rights, Maybe
However, in some jurisdictions (including some, but not all, US states) a natural person has personality rights, sometimes also called rights of publicity. Where these rights are recognized, one cannot use a person's name, image, voice, or "persona" to market a commercial product without permission from the person whose identity would be used.
In some jurisdictions personality rights end with the death of the person, in others they last for a number of years after the person's death. Without knowing the specific jurisdiction involved, it is not possible to say what rights the family of the professor might have under this theory. In some jurisdictions the matter is not yet clearly settled.
The relevant jurisdiction is usually the place where the person resides, or resided at the time of the person's death.
One would be wise to do research on personality rights in the relevant jurisdiction, or engage a lawyer who is knowledgeable in this area.