Wizard: A scientific explanation of magic

Slow paced, absolutely rational protagonist, no mercy, never lost, slightly cool.
Medieval European background.
Magic and wizards.
A young man of the 21st century who travels to become second in line to become a baron, Richard shrugs off the decadence of aristocratic life. Instead, he accidentally learned about the extraordinary powers of wizards through scientific research. From then on, this dull life is gone forever.
Richard set out in the magical world with a scientific vision and started a legendary wizard journey.