Back to Paris and Pierre
Marie decided to return to Paris and begin a Ph.D. degree in physics.Back in Paris, in the year 1895, aged 28, she married Pierre Curie. Pierre had proposed to her before her journey back to Poland. Aged 36, he had only recently completed a Ph.D. in physics himself and had become a professor. He had written his Ph.D. thesis after years of delay, because Marie had encouraged him to.Pierre was already a highly respected industrial scientist and inventor, who, when aged just 21, had discovered the piezoelectric effect with his brother Jacques. Pierre was also an expert in magnetism, and he discovered the effect now called the Curie Point where a change of temperature has a large effect on a magnets properties.