State Sen. Daniel Biss touts his background as a mathematician as he campaigns for governor, calling himself the “Skinny Math Man” ready to tackle the state’s hardest problems.

But it turns out the former math professor’s claims don’t completely add up. Some of his published papers were found to contain flaws, some deemed “critical” errors by fellow mathematicians.

Biss — elected in 2010 to the Illinois House of Representatives and to the state Senate in 2012 — graduated from Harvard University with a bachelor’s degree, and earned his Ph.D in mathematics at the Massachusetts Institute of Technology. At 25, he joined the University of Chicago’s mathematics faculty, according to his campaign website biography. Biss is one of eight vying for the Democratic gubernatorial primary in March.

The Sun-Times inquired about some errors made in the Evanston Democrat’s mathematical papers, including an “erratum” — or an error in printing or writing — made to the Annals of Mathematics about a 2003 paper and another “erratum” submitted for a paper he wrote in 2006. Another paper from 2002 was retracted. Some of the errors were noted on Retraction Watch, which tracks scientific errors.

The website in February noted a retraction in a paper Biss wrote in 2002. “Topology and its Applications” wrote that the article was retracted “after receiving a complaint about anomalies.” The editors asked for further reviews “which indicated that the definitions in the paper are ambiguous and most results were false.” The website followed up and said the journal noted the findings were “inaccurate” but “not fraudulent.”

Editors of “Topology and its Applications” said Biss was contacted with “twelve specific, documented errors” and asked to review the findings.

“We offered him the opportunity, if Biss felt it to be appropriate, to publish an addendum in Topology and its Applications. Biss responded with ‘Thank you for writing. I am no longer in mathematics and so don’t feel equipped to fully evaluate these claims. I certainly do not dispute them. If you would like to publish a retraction to that effect, that would seem to me to be an appropriate course of action,'” editors told Retraction Watch.

The problem with that, Retraction Watch noted, is that the paper was cited 27 times since it was first published. The site also notes two other “errata” for papers Biss published — with a Russian mathematician named Nikolai Mnev pointing out the errors.

Biss’ math expertise is in the forefront because he has chosen to make it a focal point in his gubernatorial campaign. His campaign logo is four circles that form a plus sign, noting his “lifelong love of math” which his campaign says has “shaped his desire to tackle difficult problems.” And in a fundraising email sent on Sept. 24, Biss wrote that “as a former teacher I know that math is incredibly important.”

“We need basic arithmetic to manage our personal finances so we can pay the bills. We can use similar math — and maybe some linear algebra — to calculate whether or not the millionaires and billionaires are paying their fair share. Spoiler alert: I’ve done the calculations — in Illinois, they aren’t,” Biss said in the email.

Biss’ campaign noted that “in a few cases” some of his papers “didn’t stand up.” But they said “revisions” are part of a normal part of the academic process. A CBS News story from 2015 noted that just 0.02 percent of some three million mathematical papers were retracted, but retractions are not necessarily seen as a bad thing. Instead, many view them as a better option than scientists and mathematicians choosing to let their errors live on in the academic realm.

“Theoretical mathematics is a field built on proposing new ideas that are scrutinized by peers over time, revised and perfected to move understanding forward,” Biss’s campaign said. “Whether it was training at MIT or the University of Chicago, Daniel has had dozens of academic papers reviewed by his peers and published. In a few cases, further research has found that the case posited in the original article didn’t stand up, and he revised his findings.”

Biss’ campaign pinned the blame for the issue on perceived Democratic gubernatorial frontrunner J.B. Pritzker.

“We understand that in the heat of political campaigns operatives will push silly opposition research, but these attacks don’t add up,” Biss spokesman Hari Sevugan said in a statement. “More likely, the math problem that’s really bugging folks is why a centrist billionaire who has already cut his campaign over $20 million in checks to fund TV ads can’t seem to blow away a unapologetically progressive middle-class math professor,” Biss’s campaign said in a statement.

Asked to respond, Pritzker’s campaign had no comment.