Quantum computing and the quantum internet are technologies becoming increasingly close to mainstream use and integration in the near future, but what exactly is a quantum internet, and what would it mean for today’s world? Here we explore the upper limits of the quantum internet by taking it to the nth degree.
2019 was a huge year for quantum technology with the beginning seeing teleportation of information occur within a diamond and the year ending with this being achieved between two computer chips. This makes it likely that as 2020 and the next few years progress we may see quantum computing technologies reach the mainstream consumer market, with the hope of eventually developing a quantum internet.
A quantum internet would use the principles of quantum mechanics (superposition, entanglement, teleportation and tunnelling) to create an internet that much resembles the current world wide web to the user but would in fact greatly boost our communication abilities and would truly represent a new stage of our lives on a galactic scale. But how would this happen, what’s so different about a quantum internet and what benefits does it provide regarding the continuing progress of our species?
Firstly, we can use the principles of superposition and entanglement, discussed in my previous summaries, to develop much smaller and much more powerful computing systems. This is because quantum phenomena rely on manipulation of individual atoms and particles rather than circuits and transistors. In quantum computing we use superposition and entanglement of miniscule particles such a s electrons, photons or atoms to act as logic gates. Typically our AND and OR gates are made with metal parts and while they have decreased in size rapidly, can only ever be as small as about 14nm under classical electrical circuitry conditions. Atoms are an order of magnitude smaller than this, too small for the frequencies of typical circuitry to have an impact. This is why we must use the quirks of the fundamental particles to our advantage if we hope to make ever smaller and more powerful computers. This however, isn’t the main benefit of quantum technology.
Not only does developing usual logic gates out of individual atoms allow for smaller versions of our current computer systems, quantum phenomena open an avenue for faster searching and processing by acting as complex logic gates which typically would need a network of classical circuitry to achieve. By producing graded outputs, quantum processes exponentially improve on our current binary (0s and 1s) computing systems. This allows a quantum computer to search a database in a single process whereas classical computers must run as many processes as their are items in the database to discern the correct response.
This is all great for simulating neural networks like the human brain, complex algorithms and cosmological simulations but the real fun starts when we step away from the logic gates in a single system, to correlating two quantum systems such that the information in one part of system A is instantly available (or able to cause an instant change in) system B. This is precisely what has been achieved in the aforementioned chip to chip teleportation. The reason this is so relevant to future technology is that it demonstrates that we can develop a network of systems that are not governed by the universal speed limit; lightspeed.
Allowing information to be instantly available to a distant system has massive implications. Radiowaves are the usual range of our frequencies used for all of our internet surfing and tv watching which are governed by the speed of light in a vacuum (3.0×10^8m/s). This is what causes delays between live news feeds to Australia or any sufficiently distant country. This is quite literally because light takes time to get from the reporter, be converted into radiowaves, sent to a mast then a satellite, the correct destination is selected and the signal sent to the closest mast to the studio in your home country before appearing on your screen. In quantum terms, this is slow going and the problem only gets worse as we start to traverse the wider solar system and beyond. Over Galactic distances the radio signals would take impractical amounts of time. We are already limited by classical systems when receiving “real-time” data from mars rovers as they attempt to land. The delay can be anywhere from 30 seconds to 20 minutes depending on the orbital positioning of each planet from the other. So in effect it has already landed (or failed to land) before we know about it.
A quantum based system would not have these issues. Firstly the processing of the information would be quicker, speeding up the process of sending, receiving and converting signals into the relevant format. But more than this, it would allow instant communication between any given distance through the instant inference of a distant system’s state. So a live feed from mars or Pluto would truly be live, raising intriguing questions about the nature of time, initially thought to be relative and having no absolute present throughout the universe. If you’d like to understand more about that part, it’s coming in a later article. But the quantum internet’s uses are not fully explored yet.
When it comes to space travel, there are several safety and time related hurdles to overcome. If we were to send humans toward a planet 100 light years away, say for argument’s sake they could travel there at the speed of light, when they got there it would be 100 years later on Earth. No time would have passed for them, but that’s just a quirk of the relativity of time and light. Using classical internet it would take a further 100 years for the signal from the humans on the new planet to reach Earth again, meaning Earth has to wait 200 years to confirm the success or failure of the distant humans’ journey.
A quantum internet means that upon reaching the new planet, a signal is received by Earth, halving the confirmation time from Earth’s perspective. This assures instantaneous communication across massive galactic distances. We can be in constant contact with the humans on the ship the whole time with no delays between messages. This is hugely beneficial for the future of space colonisation, technological advances and automation of infrastructure and navigation systems.
There are of course still hurdles to overcome to fully utilise quantum processes on this scale. Quantum Entanglement is easily perturbed by external influences such as heated particles and stray photons, so at present the largest part of quantum computers is there massive cooling and isolating mechanisms which reduce the temperature in the quantum circuitry (usually a film of atoms entangleable through induced phase transitions) to near absolute zero (about -273°C). This was the main method in Google researchers paper claiming quantum supremacy, a claim which quickly became controversial. This isn’t practical in your handheld device and research is focusing on less easily perturbed setups and materials, with the prime example potentially being the human brain.
Once this hurdle has been overcome and we have more stable examples of quantum entanglement (somewhat an oxymoron) then we could theoretically send one into a black hole with the necessary recording equipment and actually be able to receive quantum information from points past the event horizon, where no signals in the electromagentic spectrum can escape the gravity.
So, that’s a glimpse at what a quantum internet means when taken to the nth degree. If you enjoyed it or have any questions or suggestions let me know and stay tuned for more on the possibility of detecting aliens using the quantum internet and much much more!