The past, it has been said, is a foreign country. And sometimes itâs another country we yearn to visit.
We canât, of course. Whereas actual travel is limited only by how much cash we can spare, visa requirements and flight cancellations, journeying to times gone by is limited by the cold, hard laws of physics.
Or maybe itâs not.
Joining the ranks of movie inventors like Doc Brown of âBack to the Futureâ are a few real-life scientists currently trying to realize the dream of turning back the clock to travel to the ultimate destination.
Among them is Ron Mallett, an astrophysicist who has dedicated much of his adult life to the notion that time travel is possible. Heâs come up with the scientific equations and principles upon which he says a time machine could be created.
While acknowledging that his theories and designs are unlikely to allow time travel in his lifetime, for years heâs been working in parallel to a respected academic career to fulfill his dream of venturing back in time to see his beloved father again.
Mallett was aged 10 when his father died suddenly, of a heart attack, an event that the scientist says changed the track of his life forever.
âFor me, the sun rose and set on him, he was just the center of things,â he tells CNN Travel. âEven today, after all of these years, thereâs still an unreality about it for me.â
Mallettâs father, a TV repair man, instilled in his son a love of reading, and encouraged his budding passion for science. About a year after his fatherâs death, a grieving Mallett stumbled across an illustrated version of the classic sci-fi novel âThe Time Machine.â
âThe book that changed my life,â he says.
Thanks to the imagination of author H.G. Wells, suddenly Mallett felt his family tragedy presented not an end â but a beginning.
Sixty years later, 74-year-old Mallett is a professor of physics at the University of Connecticut. Heâs spent his career investigating black holes and general relativity â the theories of space, time and gravity famously explored by Albert Einstein.
Mallett has also been theorizing about time travel, in the course of which he has embarked on his own personal journey: a complex and often contentious quest to build a machine capable of visiting the past.
Heâs still a long way from his destination â some would argue heâll never get there â but his voyage makes for a poignant story that dwells on the power of love, the potency of childhood dreams and the human desire to control destiny in an unknowable universe.
How to become a time traveler

Mallett first encountered the concept of time travel back in the 1950s.
âWe hadnât even gone into space,â he recalls. âAnd people werenât even sure if we could.â
Growing up in New York Cityâs Bronx neighborhood, and later in Pennsylvania, Mallettâs family struggled for money.
As a self-described âbookaholicâ he still found ways to get hold of reading material, finding comfort, after his fatherâs death, among the the shelves of the local Salvation Army bookstore.
It was here that Mallett encountered the writings of Einstein, his next key inspiration.
He continued poring over science books throughout his teenage years and, after leaving high school, aimed for college via the G.I. Bill which supports US military veterans in their post-service education.
He enlisted in the US Air Force, where he served for four years, including deployment to Vietnam.
Eventually, Mallett made it to academia. He gained a bachelorâs degree in physics, followed by a masterâs and a doctorate, specializing in Einsteinâs theory.
His first job was working on lasers at United Technologies, an aircraft manufacturer, looking into how they could be used to bore holes in the turbine blades of jet engines.
After a couple of years of applying mathematical theories in this practical setting, Mallet joined the University of Connecticut (UCONN) as an assistant professor of physics.
Through all of this, from Vietnam to back again, Mallett was quietly considering the possibility of time travel.
But he only began speaking publicly about his ambitions once UCONN made him a tenured professor, an open-ended academic position that grants holders the freedom to work largely free from fear of dismissal.
âI wanted to make sure that I got to that pinnacle of professionalism,â he says, âEven then I was a bit reluctant.â
He was aware of the âmad professorâ stereotype. He wanted to ensure his ambitions werenât ridiculed and his job threatened.
But when Mallett began speaking openly about his ideas, he found they struck a chord with many others, something he says shows the universality of the desire to revisit the past. We all have, he says, regrets, or past decisions we wonder about, or people weâve lost who we long to see again.
âPeople started contacting me, literally from all over the world about the possibility of going back in time,â he says.
The science behind it all

Today, photos of Mallett at work show him surrounded by equipment in a cluttered laboratory, demonstrating his principles at work via small-scale experiments â or standing, beaming, in front of chalk boards where heâs etched out his formulas.
The personal aspect of Mallettâs work is profoundly moving, but how plausible is the science behind his ideas?
It all hinges, says Mallett, on Einsteinâs special theory of relativity and general theory of relativity.
âTo put it in a nutshell, Einstein said that time can be affected by speed,â says Mallett.
Mallett gives the example of astronauts traversing space in a rocket thatâs traveling close to the speed of light. Time would pass differently on Earth than it would for the people in the rocket.
âThey could actually come back finding out that theyâre only a few years older, but decades have passed here on Earth,â he says.
Mallett points to the 1968 sci-fi classic movie âPlanet of the Apes,â at the end of which [spoiler alert] an astronaut realizes that he hasnât traveled to a distant, ape-ruled planet, but merely returned to Earth in a post-apocalyptic future in which mankind has been subjugated by simians.
âThat is an accurate representation of Einsteinâs special theory of relativity,â says Mallet. âSo the upshot is that, according to the special theory of relativity, if youâre traveling fast enough, you respectively are traveling through time. And effectively, that would be a representation of time travel.â
However, this is all about going forward not backward, so how would this help Mallettâs quest to be reunited with his father?
Einsteinâs general theory of relativity is based in the concept of gravity â and considers how time is affected by gravity.
âWhat Einstein meant by that is the stronger gravity is, the more time will slow down,â says Mallett.
Einsteinâs general theory of relativity says that what we call the force of gravity isnât a force at all, itâs actually the bending of space by a massive object.
âIf you can bend space, thereâs a possibility of you twisting space,â says Mallett.
âIn Einsteinâs theory, what we call space also involves time â thatâs why itâs called space time, whatever it is you do to space also happens to time.â
Mallett posits that by twisting time into a loop, one could travel from the future back to the past â and then back to the future. And this is the idea of a wormhole, a sort of tunnel with two openings.
Mallett suggests that light could also be used to affect time via something called a ring laser.

Heâs created a prototype illustrating how lasers could be used to create a circulating beam of light that twists space and time â inspired by his first job experimenting with lasersâ effect on airplane jet engines.
âIt turned out my understanding about lasers eventually helped me in my breakthrough with understanding how I might be able to find a whole new way for the basis of a time machine,â says Mallett.
âBy studying the type of gravitational field that was produced by a ring laser, this could lead to a new way of looking at the possibility of a time machine based on a circulating beam of light.â
Mallettâs also got a theoretical equation that, he argues, proves this would work.
âEventually a circulating beam of laser lights could act as a sort of a time machine and cause a twisting of time that would allow you to go back into the past,â he says.
Thereâs a snag though â a pretty big one.
âYou can send information back, but you can only send it back to the point at which you turn the machine on,â says Mallett.
While his quest to go back to the 1950s isnât anywhere closer to a reality, he remains optimistic, and continues to ponder possibilities.
Realities of time travel

So could there be a not-too-distant future in which time travel is part of our daily reality? After all, weâre entering a new decade in which once fanciful concepts like space tourism and hyperloop trains are entering the realms of possibility.
Maybe, but not everyone thinks so.
âTime travel into the past is allowed, potentially, in our theory of general relativity, how we understand gravity,â says Paul Sutter, an astrophysicist who hosts a podcast called âAsk a Spaceman!â
âBut every time we try to concoct a theoretical time travel device, some other bit of physics busts in and breaks up the party.â
Sutter says he is aware of Mallettâs work, and thinks itâs interesting, if not necessarily on track to deliver results.
âI donât think itâs necessarily going to be fruitful, because I do think that there are deep flaws in his mathematics and his theory, and so a practical device seems unattainable.â
Serious criticism of Mallettâs theory was voiced in 2005 by Ken D. Olum and Allen Everett, of the Institute of Cosmology, Department of Physics and Astronomy at Tufts University. They said theyâd found holes in Mallettâs equation and the practicality of his proposed device.
British science writer Brian Clegg looks more favorably on Mallettâs ideas, he also profiled the scientist in his book, âHow to Build a Time Machine.â
âWhile not everyone agrees that his planned device would work, I think itâs an interesting enough proposition to go for an experimental trial,â says Clegg.
âIf it did work, it should be stressed that itâs not a practical time machine, it would simply produce a tiny but measurable effect, which would demonstrate the principle.â
Mallett is quick to clarify that his ideas are theoretical.
He says heâs currently trying to get funds to conduct real-life experiments.
âItâs not like the movies,â says Mallett. âItâs not going happen at the end of two hours, at the cost of whatever it is you pay for the movie ticket. Itâs going to cost.â
Movie comparisons are a common theme of conversation with Mallett. He relishes explaining concepts about time travel through cinematic examples.
When asked about the ethical implications of going back to the past, he suggests thereâd be a need for international regulation and policing, and namechecks 1994 movie âTimecop,â in which Jean-Claude Van Damme plays an officer working for an agency regulating time travel.
Another favorite, says Mallett, is the 2014 Christopher Nolan movie âInterstellar,â which deals in ideas of how time impacts people in space differently than people on Earth.
That movieâs scientific credentials were boosted by the involvement of Nobel prize-winning theoretical physicist Kip Thorne.
But Mallet also appreciates the emotional core of the movie â the father-daughter story that drives the plot: âItâs beautiful,â he says.
Movie magic

Hollywood has come calling for Mallett a few times. A proposed adaptation of âThe Time Traveler,â an autobiography he co-authored in 2008, fell through despite the involvement of celebrated director Spike Lee.
Mallett says a major production company has now bought the rights to his story and thereâs another cinematic project in the works.
Even after a lifetime spent investigating time travel, Mallet may never physically go back to 1950s New York.
But, thanks to the magic of cinema, he may yet get a glimpse of the past, that âforeign countryâ, and, in a way, meet his father one last time.
âThe idea I will actually be able to see my father on the big screen, it will almost be like bringing him back to life for me,â says Mallett, poignantly.