At the Institute for Earth and Space Exploration at Western University in Canada, students, by their own account, have achieved the first international teleportation – the hologram of a person was instantaneously teleported across borders. Do such headlines wow you?
Wow may be an exaggeration because NASA had teleported an astronaut to outer space three-dimensionally several months earlier. Obviously, it would be fantastic if in the future we were able to interact with others in 3D, as if they were standing in front of us, and practically being able to walk around them instead of just talking to them on a flat screen like in a Zoom conference. Truth be told, though, the vocabulary calls for clarification. What was achieved in Canada has nothing to do with teleportation because there was no person physically taken from one place to another but a 3D image. That’s no doubt an amazing feat too, but, from a technological perspective, teleporting would be dramatically different.

Star Trek fans would call it beaming.
Right. By contrast, physicists tend to use the term quantum teleportation, which, essentially, is about creating entangled photons. These light particles are coupled in a way that when the state of one changes it will automatically cause the state of the other, spatially separate, partner to change. Irrespective of the distance. This technology is an enabler of superfast quantum computers and bug-proof communications. Today, that’s probably more important than ever.

But doesn’t beaming entail a lot more than that? Matter would have to dematerialize.
Yes, it does. From a purely physical perspective, that’s conceivable. According to Einstein’s theory of relativity, every form of mass has a corresponding energy. Consequently, according to his famous formula E = mc2, the mass of a human being would have to be multiplied by the speed of light – squared. That’s where the problems start, if not earlier. Mathematically, this dissolution process would release enough energy to supply an industrial nation like Germany for one year. That humongous amount would then have to be controlled somehow. Technically, that’s hard to imagine from today’s perspective, aside from the fact that, before assembling them, the locations of all the human atoms would have to be determined precisely. All in all, these are huge hurdles. But Neanderthals couldn’t imagine a Concorde either. I predict that beaming will not be feasible in the next 100 years.

Let’s beam ourselves back into reality. In the so-called two-way teleportation that was achieved in Canada, a special camera was used for filming from different perspectives. The user at the other end of the “line” has to wear a mixed-reality headset creating the three-dimensional impression. Why is that HoloLens headset still necessary?
Because otherwise the person’s information could not be transmitted. You see, you need a special laser light to generate a holographic image. That requires so much information to be sent that its transmission in real time without a headset would not be possible today. The headset could perhaps be designed in even smarter ways, or be integrated into normal glasses.

What would it take to eliminate the need for headsets?
A further acceleration of data transmission speed and a technology enabling holograms to be projected in a room, just like that. It would take a technology that makes laser light visible in a room. In the case of a hologram, that would be something three-dimensional.

© Swen Pförtner/Universität Göttingen

“How great would it be if a personal trainer could join their client in 3D for a realistic workout session!”

Even with these headsets a hologram “sent” in real time that you can think of as a digital twin is a technological step ahead, isn’t it?
Absolutely. I don’t mean to play this experiment down. Imagine a doctor having a three-dimensional image of you. In that case, he or she could examine you at least externally, anywhere, and much better than in 2D on a screen. The doctor could see discolorations on your skin or if you perspire in unusual places. That’s a huge step forward, for instance enabling medical care in remote areas. That can mean massive cost savings for the healthcare system.

Then it would obviously be optimal if haptics became an additional element.
Clearly, the hurdles with holograms are high in that case. But not too high. Let’s assume the doctor applies pressure against your kneecap. You’d have to wear a suit triggering a corresponding impulse. Unfortunately, you can’t apply pressure just with the help of light. Concerning those headsets, it might be possible to integrate biosensors in them that additionally monitor a patient’s heart rate and oxygen saturation in the blood.

So, such holograms are more than a social “nice to have?”
Yes, of course. But even if the headsets delivered no more than social value I’d say, wow! It would be great if everyone had such a headset at home as a normal item like a computer or smartphone. Imagine your uncle from the U.S. virtually standing in front of you on your birthday. Or an astronaut in space visiting their family at night. Or a concert by your favorite star transmitted live to your living room as a hologram. There are infinite conceivable scenarios. Also, how great would it be if a personal trainer could join their client in 3D for a realistic workout session? That would make sense especially in times of a pandemic.

Do you see other specific applications in business and industry?
Yes, I do. Obviously, once this technology is able to transmit an entire room, a wide variety of assistance can be provided. Like, you need to tighten that screw here, you need to connect that cable there. I can imagine a lot of applications along those lines. For example, the columns of a spreadsheet could project from a meeting room. Or a machine in a factory hall could actively alert me to a problem and I’d ask a technician to join me – no matter where he or she may be located at that time. People building a house can digitally walk through their new life-size home in advance. Or I could create virtual office floors and lecture halls. 50 years from now, that may be part of normal, everyday life for all of us.

Thank you very much for the interview.