There’s an unmistakable paradox surrounding the sudden death of Ron Mallett’s father when Mallett was an impressionable kid growing up in the Bronx: Had Boyd Mallett survived, his son never would have devoted himself with such obsessive zeal to unraveling the mystery of time travel in hopes of saving his father’s life.

Should Ron Mallett someday succeed — traveling backwards in a time machine to warn his father about this two-pack-a-day smoking habit — he would, in theory, be extinguishing the flame that has burned inside him for decades.

(Have you seen the movie “Interstellar”? Yeah, it’s kinda like that.)

“My love for him is still as strong as it was 60 years ago,” Ron Mallett told The Washington Post of his father, who died in 1955 at age 33. “When I’m on my death bed, I will be thinking of him. His death is the reason I am what I am.”

What he is is a 69-year-old theoretical physicist at the University of Connecticut who, at the tail end of a celebrated career, finds himself closer than ever to building the time machine that has mesmerized him since childhood.

Mallett’s work is rooted in the work of Albert Einstein’s general theory of relativity. His greatest achievement is a 15-year-old theoretical equation that, he believes, holds the key to finding his father and revolutionizing the way we think about time. To test the equation, Mallett needs to raise $250,000 for a feasibility study.

“People don’t realize how expensive research is,” he told The Post. “The Wright Brothers didn’t just build a plane. First, they actually built a wind tunnel to determine the best configurations for aircraft wings. When it comes to a time machine, we need to build the wind tunnel before we can think about building the plane.”

Einstein understood that if space could be twisted, then time could also be “twisted and bent back on itself to form loops,” according to Bloomberg. Based on that insight, the crux of Mallett’s theory is that a circulating beam of light is an even more effective way of twisting space and time.

Mallett likes to demonstrate his theory using a coffee cup:

Mallett proudly promotes his coffee cup demonstration now; but when he received his doctorate in 1973, he kept his time travel obsession quiet. At the time, he was one of only 79 African Americans among about 20,000 PhD physicists in the country, according to Bloomberg.

Boyd Mallet is seen fixing a television before his death at age 33. (Courtesy of Ronald Mallett)

Discrimination in the field was much more prevalent at that time, Mallett said, and he worried that his interest in time travel would derail his chance of receiving tenure.

“Because of the fact that there were so few of us, I knew that I had to step carefully,” he said. “But I’ve always felt like the best way of getting back was achieving success.”

It’s an attitude he picked up early from his father, a World War II veteran who served as a medic in Europe before returning home and using the GI bill to enroll in technical college. There, he reinvented himself as a television repairman.

At home, however, Mallett’s father was intensely focused on grooming his family for even bigger things. He forced his kids to listen to classical music radio broadcasts and read poetry. He reveled in taking apart the family television set and showing his mechanically minded son how the entrails worked in concert. He believed strongly in the importance of education, Mallett recalls, and would only dole out his son’s allowance if his son could pass a multiplication test.

“If I ever have a chance to talk to him, I’d want to ask him what motivated him to go into electronics and become the renaissance man that he was becoming,” Mallett said, noting that his father grew up the poor son of a Pennsylvania brick-maker. “It’s like he was trying to build himself into a cultured, educated person and he was doing it all on his own.”

His father’s death from a heart attack at 33 plunged the family into poverty and sent 10-year-old Mallett into a crushing period of depression.

“He looked like this strong, robust man,” Mallett once told the Boston Phoenix. “When he died of this massive heart attack, it was as though the impossible had happened He was like Superman. I was just in a daze.”

The family relocated to Altoona, Penn., where what little money Mallett received from his mother was spent on five-cent books from the Salvation Army. Fueled by fantasies of time travel, those books quickly became a means of escape.

After graduating from high school, Mallett enlisted in the Air Force and spent four years as a computer technician for Strategic Air Command at Lockbourne Air Force Base outside Columbus.

Eventually, he earned his doctorate and was hired by United Technologies, where he spent two years working with lasers. Although he longed for academia, his understanding of lasers would prove invaluable decades later as he developed his theory about using light to bend time.

Ronald Mallett draws a diagram of his ring laser on a whiteboard in a University of Connecticut laboratory. (Scott Eisen/Bloomberg)

As he nears the end of his career, Mallett, who is married and has two stepchildren, is pushing on.

And what better time to do so? This year, Bloomberg notes, is “the 100th anniversary of Einstein’s general theory of relativity that made time travel a serious topic among today’s theoreticians and the 60th anniversary of his father’s death.”

Spike Lee bought the rights to Mallett’s 2006 autobiography, “Time Traveler,” and is shopping a script, the scientist said.

He’s raised only $11,000 of the $250,000 he needs to carry out his crucial experiments. He is at once helped and hampered by the very notion of time travel, a concept that galvanizes as much dismissal as curiosity.

“What people have to realize is that this is real science,” Mallett said. “The Wright Brothers had been able to get the financing they needed for their wind tunnels, it would have advanced things faster.”

With the aviation pioneers in mind, he finds comfort in a quote by Simon Newcomb, the onetime director of the U.S. Naval Observatory: “Flight by machines heavier than air is impractical and insignificant, if not utterly impossible.”

“Newcomb made his statement in 1902,” Mallett notes. “In 1903, the Wright Brothers flew for the first time.”