David Kaiser is a professor of the history of science at the Massachusetts Institute of Technology and the author of “How the Hippies Saved Physics: Science, Counterculture, and the Quantum Revival.”

THERE must be an election coming up. I know this because of the number of times I have been getting a certain e-mail, one that begins, “Take the three minutes to read this. Maybe he is wrong, but what if he’s right?” I first received the e-mail — which includes an essay railing against President Obama and the Federal Reserve — back in March 2009, just weeks after the president’s inauguration. Since then, 267 people have e-mailed me about it; about two dozen more have called my office to talk about it. A vast majority of them agree with the essay’s sentiments and want to compliment me for my work.

The essay, which has been promoted on blogs across the Internet, is attributed to a person named David Kaiser. As it happens, my name is David Kaiser. We are not the same person. In fact, the e-mail states clearly that it was written by a historian and “professor in the Strategy and Policy Department of the United States Naval War College.” Some versions included a photo of this David Kaiser, taken from his Wikipedia entry. I teach physics and the history of science at the Massachusetts Institute of Technology, and my Web site includes a photograph of myself right next to my e-mail address. We look nothing alike.

The essay includes a short curriculum vitae for the professor (now retired from the Naval War College), the names of several of his books and his prior teaching appointments. Each of those items is true, except for one detail: that David Kaiser did not write it, either.

After the false attribution, the essay launches into a tirade against the president that culminates in a comparison between him and Adolf Hitler. There are elementary flaws throughout — Winston Churchill never served in the British House of Lords, for one — piled on top of outlandish claims like the one that Mr. Obama promised to “create and fund a mandatory civilian defense force stronger than our military for use inside our borders.” In between are sneering gibes at religious minorities, schoolteachers and supporters of same-sex marriage....