An American physicist who helped develop the hydrogen bomb—many times more powerful than the atomic bomb that killed some 80,000 people in Hiroshima—has ignored an order from the Department of Energy to cut significant portions of his memoir, The New York Times reports.

The book's author, Kenneth W. Ford, 88, has not worked on weapons since 1953. Building the H Bomb: A Personal History will be his 10th book.

Ford volunteered his manuscript for security review by the Department of Energy last year. In September, federal officials told him to remove about 10 percent of the book, or around 5,000 words. "Our team is quite taken with your manuscript," an official reportedly wrote. "However, some concerns have been identified."

From the Times:

The government's main concern seems to center on deep science that Dr. Ford articulates with clarity. Over and over, the book discusses thermal equilibrium, the discovery that the temperature of the hydrogen fuel and the radiation could match each other during the explosion. Originally, the perceived lack of such an effect had seemed to doom the proposed weapon. The breakthrough has apparently been discussed openly for years. For instance, the National Academy of Sciences in 2009 published a biographical memoir of Dr. Teller, written by Freeman J. Dyson, a noted physicist with the Institute for Advanced Study in Princeton, N.J. It details the thermal equilibrium advance in relation to the hydrogen bomb.

After months of failed negotiations, Ford decided to publish the book. "I don't want to strike a blow for humankind," he said. "I just want to get my book published."