Uploading our minds into machines will make us immortal, a scientist said.

Physicist Michio Kaku said that this is no longer just a scene in a sci-fi movie as technology will soon make it possible for people to upload their personalities into a computer and recreate themselves - somewhat alive - through virtual avatars.

"Imagine being able to speak to your loved one after they died, but it is possible if their personality has been downloaded onto computer as an avatar," Dr. Kaku said in a report published in The Daily Mail.

In Dr. Kaku's theory, the avatar will contain the person's memories and personalities, and through artificial intelligence, these virtual avatars will interact with people as they would have done in real life.

A person's avatar will be activated once he/she dies, and a hologram of the person could be beamed from the computer. Or, in the future, the dead could appear as a three-dimensional figure that could interact with people.

"You would be able to communicate with them as if they were still here. They would, in effect, become immortal," he added.

Dr. Kaku is known for his expertise in theoretical physics and is continuing his search for the so-called "Theory of Everything," which unites the four fundamental forces of nature: the strong force, the weak force, gravity and electromagnetism.

His book "The Future of the Mind" explores how technological advancements could change the way we use and understand the human brain in the next 50 to 100 years.

It may sound like science fiction, but Dr. Kaku believes that these developments are possible, though these are likely to happen by the end of the century, he said.

"In the short term, we're going to be able to connect our minds to computers, so that we'll be able to control exoskeletons," Dr. Kaku told The Daily Mail.

"Beyond that, the Internet will be replaced by the 'Brain-net', where you can convey emotions and memories rather than just text," he added.

Dr. Kaku is not the first to explore the use of human avatars. Russian billionaire Dmitry Itskov once claimed that he will make it possible for humans to live forever in the next 30 years by uploading their brains into computers