The concept, cool yet maybe a little creepy, is known as mind uploading. Think of it as a way to create a copy of your brain, a transmission of your mind and consciousness into a computer. There you would live digitally, perhaps forever. You’d have an awareness of yourself, you’d retain your memories and still feel like you. But you wouldn’t have a body.

Within that simulated environment, you could do anything you do in real life – eating, driving a car, playing sports. You could also do things impossible in the real world, like walking through walls, flying like a bird or traveling to other planets. The only limit is what science can realistically simulate.

Doable? Theoretically, mind uploading should be possible. Still, you may wonder how it could happen. After all, researchers have barely begun to understand the brain.

Yet science has a track record of turning theoretical possibilities into reality. Just because a concept seems terribly, unimaginably difficult doesn’t mean it’s impossible. Consider that science took humankind to the Moon, sequenced the human genome and eradicated smallpox. Those things too were once considered unlikely.

As a brain scientist who studies perception, I fully expect mind uploading to one day be a reality. But as of today, we’re nowhere close.

Living in a laptop

The brain is often regarded as the most complex object in the known universe. Replicating all that complexity will be extraordinarily difficult.

One requirement: The uploaded brain needs the same inputs it always had. In other words, the external world must be available to it. Even cloistered inside a computer, you would still need a simulation of your senses, a reproduction of the ability to see, hear, smell, touch, feel – as well as move, blink, detect your heart rate, set your circadian rhythm and do thousands of other things.

But why is that? Couldn’t you just exist in a pure mental bubble, inside the computer without sensory input?

Depriving people of their senses, like putting them in total darkness, or in a room without sound, is known as sensory deprivation, and it’s regarded as a form of torture. People who have trouble sensing their bodily signals – thirst, hunger, pain, an itch – often have mental health challenges.

That’s why for mind uploading to work, the simulation of your senses and the digital environment you’re in must be exceptionally accurate. Even minor distortions could have serious mental consequences.

For now, researchers don’t have the computing power, much less the scientific knowledge, to perform such simulations.

Scanning billions of pinheads

The first task for a successful mind upload: Scanning, then mapping the complete 3D structure of the human brain. This requires the equivalent of an extraordinarily sophisticated MRI machine that could detail the brain in an advanced way. At the moment, scientists are only at the very early stages of brain mapping – which includes the entire brain of a fly and tiny portions of a mouse brain.

In a few decades, a complete map of the human brain may be possible. Yet even capturing the identities of all 86 billion neurons, all smaller than a pinhead, plus their trillions of connections, still isn’t enough. Uploading this information by itself into a computer won’t accomplish much. That’s because each neuron constantly adjusts its functioning, and that has to be modeled, too.

It’s hard to know how many levels down researchers must go to make the simulated brain work. Is it enough to stop at the molecular level? Right now, no one knows.

2045? 2145? Or later?

Knowing how the brain computes things might provide a shortcut. That would let researchers simulate only the essential parts of the brain, and not all biological idiosyncrasies. It’s easier to manufacture a new car knowing how a car works, compared to attempting to scan and replicate an existing car without any knowledge of its inner workings.

However, this approach requires that scientists figure out how the brain creates thoughts – how collections of thousands to millions of neurons come together to perform the computations that make the human mind come alive. It’s hard to express how very far we are from this.

Here’s another way: Replace the 86 billion real neurons with artificial ones, one at a time. That approach would make mind uploading much easier. Right now, though, scientists can’t replace even a single real neuron with an artificial one.

But keep in mind the pace of technology is accelerating exponentially. It’s reasonable to expect spectacular improvements in computing power and artificial intelligence in the coming decades.

One other thing is certain: Mind uploading will certainly have no problem finding funding. Many billionaires appear glad to part with lots of their money for a shot at living forever.

Although the challenges are enormous and the path forward uncertain, I believe that one day, mind uploading will be a reality. The most optimistic forecasts pinpoint the year 2045, only 20 years from now. Others say the end of this century.

But in my mind, both of these predictions are probably too optimistic. I would be shocked if mind uploading works in the next 100 years. But it might happen in 200 – which means the first person to live forever could be born in your lifetime.

Dobromir Rahnev, Associate Professor of Psychology, Georgia Institute of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.