17/05/2017 8:45 PM AEST | Updated 18/05/2017 4:24 PM AEST

How Saroo Brierley From 'Lion' Fused Google And Memory To Return Home

Where is he now?

When Saroo Brierley, an Indian-born businessman with a love of physics, came to Australia, he experienced what he describes as 'astral projections'.

"I would go to sleep and wake in the morning with a sore head because I had never really slept. My subconscious was always moving," Brierley told Huffpost Australia.

They were there for a reason.

"An astral projection is an outer body experience. I was leaving my body and materialising at the door of my house when I was a boy. I would go in, hover over my family and tell them that I was okay. There was that, and recurring dreams. At the time, I didn't know what they meant."

Years later, he has a much clearer picture.

"They were there for a reason. They were guidance from my brother, and the energy of the universe pushing and pulling to find my way back home."

Saroo Brierley's story -- a long struggle to track down his birth mother and home town in India -- is both well-known and loved.

Tommaso Boddi via Getty Images
Saroo Brierley (left), with Sunny Pawar and Dev Patel.

Documented first by Brierley in his memoir A Long Way Home, it was retold through the acclaimed Australian drama 'Lion', starring Dev Patel (as Brierley) and Nicole Kidman, that reached resounding heights earlier this year.

And while his life story has been well and truly set out on a world's stage, there are some parts that Brierley does not often talk about. Like his astral projections.

I was a lost child, not an unwanted one. That would have been a different story.

"It is a personal story," he said at an event hosted by Google Australia last month, and one that was shaped by a fusion between technology and memory.

"Saroo's story is a very Australian story," Engineering Director of Google Maps Australia & New Zealand, Casey Whitelaw said.

"We have been working with Google Maps for many years now and so seeing the kinds of things that we have contributed to in the world is really special for us."

Saroo Brierley is a funny guy, with an incredible story to boot.

The memories

Brierley's story started in the slum suburbs of India.

"When I close my eyes, I picture a very dry place. In the state of Madhya Pradesh, which is the biggest state in India, you see some greenery but it is mainly dry and dusty," Brierley said. "I thought of my town as the moon."

Brierley's mother was a brick labourer on a construction site, a detail to which the film offered a slight poetic variance. To return home would take her three to four hours. And so his early memories are those of him looking after his sister.

"She was my best friend and she was only three years of age," Brierley said. "She was so tiny, so little. I used to wash her fingers and her feet because they were so muddy.

That's all I had of my past. If I had lost those memories, I would have lost everything.

"There was a lot of roaming around as well -- walking around town, from the three-platform train station, to the cinema to the markets, to the water tower and the ravine."

And it is these early memories that allowed Brierley to return home, 25 years later.

"That's all I had of my past. If I had lost those (memories), I would have lost everything," Brierley said.

"I was a lost child, not an unwanted one. That would have been a different story."

As the film depicts, a five-year-old Brierley becomes lost at a railway station in the neighbouring town of Buhanpur after parting with his brother.

"I made that irrational, impulse decision. I boarded the train, thinking he'd be in one of the nearby carriages, thinking if I went to sleep, he would find me and we could continue onto wherever we were supposed to go," Brierley said.

"I ended up 32 hours, 1,600 kilometres away from Buhanpur, in Kolkata."

Hindustan Times via Getty Images
Child actor Sunny Pawar has been heralded for playing a young Saroo.

From there came a journey that saw a young boy traipse through Kolkata, the second largest city in India, almost drown twice in the Hooghly river, escape boy gangs and spend time in two prisons before moving into an adoption home and finding himself in Tasmania.

As an adult living in Australia 25 years later, he used Google Earth to find his mother and return home.

The search

Like many, Brierley's search started with humble beginnings.

"I first saw my mum watering the garden in Hobart!" he laughed.

But his yearnings ran deeper through his adolescent years growing up in Tasmania. "The nostalgia was always there; it came into play intermittently and became more prominent in my later 20's ... It did get in the way of living a normal life."

Moving to Canberra to study at the Angliss International Hotel School, Brierley came face to face with Google Earth while working on an assignment.

"From that point onwards, it became apparent to me that this application could do more for me than just look at people's backyards."

A look at Google Maps

Google Maps started as a Sydney-based mapping start up called 'Where 2 Technologies.' The start up was acquired by Google in 2004, and became Google Maps

In the same year, Google bought a company called Keyhole specialising in mapping and satellite imagery. This, plus local search functions, created Google Maps and Google Earth as we know them today.

Brierley's search to find his Indian home town was a five-year one that moved from haphazard to diplomatic. From point B, to point A.

"My starting point was my end point: Kolkata. I didn't know where I started... when you're looking at such a huge landmass, that could have been anywhere," he said.

"I used maths: how long I was on the train for and how far it went. I created a radius line with the ruler tool and that gave me a guidance as to where I should be looking, or the places that weren't right."

I searched on my own. I thought by telling people, even my parents, that that would slow me down... I didn't want to shoot too far ahead of myself.

From there came a process of "defragmentation".

"I was joining things together that made sense. You had to think about things like the weather -- northern India is quite cool, language, wind patterns, animals and the way people dressed," Brierley explained.

This process was made easier by his photographic memory, but was barred by his recurring dreams.

"The picture became a picture. Before it was quite distorted...After searching for five years, that's what I was left with."

Call it serendipity or providence, but I thought that I should search a bit further to the west of the radius line.

One morning at approximately 2 o'clock in 2011, Brierley found his "needle in the haystack".

"Call it serendipity or providence, but I thought that I should search a bit further to the west of the radius line," Brierley said.

"I zoomed down onto the train tracks and followed them. I found Burhanpur, which was the train station I boarded the train at that night. Everything aligned perfectly. There was the water tower, there was the bridge, the ravine."

The name of his town was Khandwa.

The return

In 2012, when Brierley returned home for the first time in 25 years, he found himself at a memorable landmark.

"It was a bridge with an underpass. As soon as I got there, my legs guided me to my house. Everything looked different, but it was all muscle memory," Brierley said.

"That point where I was standing at the door in front of my house was the exact same point where I remember standing before I left 25 years ago."

And the rest is history.

On what comes next

Brierley has returned home 15 times in the last four years. And he has bought his birth mother a house.

"It's the same house that she has been living in for the last 25 years (we rented when we were kids). She didn't want to move!" Brierley laughed.

"I'm helping my brother and my sister, as well as my nieces and nephews. They are all doing okay....They're humble and grateful that I am back in their lives."

Brierley is currently working on a prequel to Lion that is set to explore the relationships between his biological mother, his adopted mother and the woman who helped him at the orphanage.

"Putting the prequel out -- a book first and hopefully a move next -- will help people to understand more in depth what Lion is about," Brierley said.

Then there's physics. "I want to get into physics and space projection. I'm not going to say what I'm going to do with it, but that's next for me!"

And the projections?

"I don't have them anymore. I haven't had them for four years."

The film 'Lion' is now available on Google Play.

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