Dowling was a consultant to Steven Spielberg's prop department on the 2002 movie remake of the H. G. Wells book, The Time Machine.

Dowling provided all the equations and figures used in the movie, including those in trailer and on all the chalkboards that appeared in the film. He carefully wrote down all the equations by hand and faxed them to Spielberg's Dreamworks studio in Hollywood, where the prop department transcribed them onto the chalkboards. While there are some transcription errors, these are all real equations, but not all about time travel.

In the middle you can see a graph, called a Minkowski diagram, showing the world line of the time machine going outside of the light cone; a hallmark of time travel into the future.

The appearance of the symbol Hg is not a reference to the element mercury, but rather a tip of the hat to H. G. Wells, the author of the the original classic book, The Time Machine.

The triple integrals were taken from Dowling's 1988 PhD thesis, (with some artistic license) so they would become immortalized on film. For example,

In 2017, one of the original chalkboards, with  Dowling's equations preserved on it, was put on display at the Barbican Art Center in London in an exhibit titled, "Into the Unknown A Journey Through Science Fiction."

photo of chalkboard
Photo credit: JohannYellowdog

While Dowling does not appear in the credits of the film, nor  on the description for this museum prop (called a "relic"), if you get the DVD of the film and check out the special features, you will hear the prop guys discuss how a "Scientist at JPL" made all the equations for them. JPL is where Dowling was working at the time in 2001. The Dreamworks prop guy that Dowling worked with was Scott Maginnis, and you can find their email exchange, preserved all these years, here. When Dowling asked Scott why Spielberg called on him to do these equations, Maginnis replied, "Stephen saw an article about your invention of quantum lithography on CNN, and told us that we needed to get you because you were a NASA physicist and would produce real equations." That CNN web page is also preserved and may be found here.

However, with no direct acknowledgment, like all good artists, you can see Jonathan Dowling's signature in the lower left.

Dowling also consulted for Sony Pictures on another time-travel movie, with the working title of Frozen, which was never produced. (No, not that Frozen.)