NARRATOR
As you round the corner of Charles Street, just north of Baltimore, a sweeping expanse of green lawn directs the eye to an imposing gray-stoned building adorned with a large, square bell tower. Wheeler Hall, as it’s known, was built in 1933, the first academic building on the campus of Loyola Blakefield High School, my alma mater.
As you climb the wide stairs to the third floor, past classrooms of students studying archaic Greek or Latin, you find the ceiling slip away, opening into an airy expanse of carved wooden beams and arches. Your nostrils fill with the musty scent of aged paper in the decaying tomes around you.
The eaves of the room house Dewey-decimalled nonfiction catalogued neatly between carrels and communal desks of students scribbling in silence. Toward the back of the room an elevated stage framed by an overwrought proscenium rises from the floor — a feature devoted to Shakespeare and works of contemporary drama. The whole space is a monument to the accrued knowledge of centuries — to the accomplished thought of past and present — to smeared ink on pulp.
But above you, atop steep wooden stairs, lies the mezzanine, a squat precipice lined not with facts, but with fantasy. In this cramped, ethereal world separate from the library’s stacks — yet still within the world of books — dreams of the future find a home in a space defined by the past.
I’m Danny Baird. This is the Invisible Network.
As a teenager, one of my favorite books that I found lingering among the mezzanine’s stacks was “Ender’s Game,” a science fiction novel by the author Orson Scott Card. It’s a childhood epic featuring a warring alien race and the precocious children destined to defeat them.
In my humble opinion, good science fiction places the reader in an unfamiliar world, rife with impossibilities. Great science fiction places the reader in a familiar one, one that echoes reality, feeling at once familiar and extraordinary.
The world of “Ender’s Game” felt that way for me. If you looked past the aliens, the interplanetary warfare, it wasn’t a world of the impossible. It was a world of limitations, of boundaries. Though science and technology had progressed beyond our time, it hadn’t crossed beyond the bounds of what seemed possible.
There was one piece of technology, though, that crossed furthest into fantasy. It was the ansible, a device that enabled faster-than-light communication. Its powers defined the logic of Card’s world, propelling plot elements and enabling the book’s surprising climax.
The word “ansible” was originally coined by fantasy and science fiction pioneer, Ursula K. Le Guin. She wrote of the device in her first novel, “Rocannon’s World,” in 1966. The book features a stranded ethnographer documenting the various life-forms and cultures he finds on a backwards, fantasy planet.
Le Guin went on to use the ansible in a number of her books, crafting rules for the use of this imaginary method of instantaneous communications. Numerous authors followed suit, paying homage to Le Guin by using the term “ansible” as the name for their own faster-than-light communications devices, each with their own rules and peculiarities.
Instantaneous communications, in general, is a staple of science fiction. Authors dream of an interconnected universe, one with limitless, immediate access to information. Could this universe be real? Could we commune with far-off galaxies in the blink of an eye?
For now, given what we know, the answer is “No.”
Einstein’s universal speed limit, the speed of light, some 186,000 miles per second, cannot yet be transcended, not even by communications. Not in any real sense. We’re trapped before this seemingly insurmountable hurdle, the speed at which energy itself flows through the universe around us.
However, we have observed something that many physicists believe does happen near-instantaneously. It’s called “spooky action at a distance.”
Richard Feynman, a theoretical physicist who won the Nobel Prize in 1965 for his work in quantum electrodynamics, once said that the quantum world only makes sense if you can “accept nature as she is: absurd.”
Quantum physics deals in the extraordinarily small particles that make up everything around us. Imagine an atom. Now imagine the pieces that make up that atom. Now imagine the pieces that make up those pieces. That’s the quantum world where spooky action lives.
Spooky action at a distance isn’t a Halloween store curio but a queer, unnerving fact of entanglement. Two particles that are entangled, or correlated with one another, predictably interact no matter the space between them. If you measure a quantum property of one, say the up or down spin of an electron, you can know, with certainty, the correlating property of its pair, no matter how far apart they are.
This spooky action happens seemingly instantaneously. Quantum physics is far from fully understood, but most physicists seem to think that quantum properties exist in all potential states until they are measured. A measurement of one part of an entangled pair would destroy the entanglement but reveal the nature of both pieces of the pair, no matter how far apart they are. One could argue that this is an exchange of information surpassing the speed limit of the universe, Einstein’s impossible threshold.
In science fiction, many authors make connections between the mysterious quantum world and seemingly impossible futuristic communications technologies. I’ve even read a book that connected “quantum foam” and time travel — “Timeline,” by the late Michael Crichton, another writer I found among the stacks of my high school library.
But does spooky action at a distance really constitute faster-than-light communication?
Imagine for a moment, that you have two astronaut friends on missions to different planets. One is on a mission to Venus aboard an airship based on NASA’s High Altitude Venus Operational Concept, or HAVOC, dreamed up by NASA’s Langley Research Center in Hampton, Virginia. She flies a dirigible through the Venusian atmosphere, above the sulfuric clouds and blistering heat of the surface. Your other astronaut friend lives in a domed, 3D-printed habitat on Mars. He studies the surface and prepares for further exploration.
You decide to send both of your friends entangled particles, with a quantum property that could either be… well, for the fun of it… let’s say they could either be a “quantum apple” or a “quantum orange.” Your friends know, ahead of time, that whichever quantum property their particle possesses, its pair will be the exact opposite. You, however, cannot know which of the entangled pairs is which, as measuring these qualities would destroy the entanglement.
Your friend on Venus receives their particle and measures it. It’s a quantum orange! Therefore, she knows your friend on Mars has just received a delicious quantum apple… That’s instantaneous communication.
But hold up. Was it?
Not really. Think about it for a second. No real information was exchanged. Yes, it’s wonderful that your friends on Venus and Mars have a quantum apple and a quantum orange and can share in the quantum fruits of your labor simultaneously, but their fruity enjoyment can only be shared at subluminal speeds. Even though your friend on Venus has a quantum orange, they’d still have to send a transmission at the speed of light to let your friend on Mars know that they’re receiving a quantum apple.
Though the initial conditions, one quantum apple and one quantum orange, allowed your friend on Venus to know what your friend received, entanglement didn’t quicken that communication practically. Your quantum apple and orange may as well have been real ones, wrapped up in a gift basket and sent by some imaginary postal service with spaceships that travel at the speed of light.
While quantum phenomena may not help us transcend nature’s seemingly impenetrable laws, they could nonetheless provide enormous benefits in the field of communications. At NASA, scientists and engineers work to take full advantage of quantum properties like spooky action at a distance. One of quantum’s most promising innovations could even secure our networks, making them near-impenetrable.
Security pervades the American zeitgeist of late. It seems hackers everywhere are looking for ways to exploit our data. Our literal and figurative fortunes rest on the ability of our devices to keep our secrets. Programmers erect firewalls and elaborate systems of encryption to keep that data safe, but sometimes their efforts aren’t enough.
In space communications, NASA doesn’t always have the advantage of the firewalls, both tangible and intangible, we erect on Earth.
Let’s say we were to send a kitten to Europa. Why not? Let’s name him Cadmus after the brother of the Phoenician princess Europa in Greek mythology.
Europa (the celestial body), is a moon of Jupiter, just a tad smaller than the Earth’s Moon. Scientists believe Europa’s cracked, icy surface hides vast oceans of liquid water. Many believe these oceans might harbor life, or at least the ingredients for it. It’s the perfect place to send a curious cat interested in science and exploration.
In this ridiculous hypothetical, Cadmus is the rare cat who loves being wet and chilly. Europa is perfect for him. We fit Cadmus with a tiny “cat-stronaut” suit and send him to the Jovian moon with all the “foods” his tiny little heart desires. He spends his days much as he did on Earth. He peers through the thick ice, searching for signs of life, just as he gazed into earthbound aquariums searching for fish. Daily, Cadmus communicates his findings and NASA responds with instructions.
How can we keep our kitten’s data secure?
There’s no ethernet cord running from mission control to this icy world. Cadmus relies on invisible waves flowing from giant antennas, spreading through the void to reach him. In these waves, NASA encodes data.
But how can Cadmus, so far away, know these commands are coming from his friends on Earth — NASA scientists guiding him through his intended mission? These messages can be encrypted, sent in a way that only Cadmus can understand. But can our celestial kitten be absolutely certain they’re not from someone else? Say, a group of malicious puppies whose goals aren’t science and discovery, but to distract poor Cadmus from his mission?
And when returning a signal to Earth, Cadmus can’t be sure that NASA alone receives the communiqué. Radio waves aren’t finely pointed affairs. As they propagate towards Earth, they may end up as wide as a continent, or even a planet. Someone could potentially intercept our astro-cat’s encoded data sent all the way from Europa and decipher it.
While NASA has apparatus in place that keep our missions safe and secure, we must stay one step ahead of hackers, developing new methods to protect them. We can encrypt our messages, but powerful computers may one day find ways to unveil their data.
How could we keep Cadmus’ data safe in the future? How can NASA make its communications un-hackable?
The quantum world and spooky action may hold the key.
Quantum key distribution, or QKD, might stymie even the most talented hackers. In fact, it might provide a truly impenetrable cipher for NASA’s data.
In QKD, mission control and Cadmus would share a random secret key encoded in quantum information known only to them. They use this to encrypt and decrypt messages.
Because the key is quantum, a hacker trying to decipher the key must measure it. This measurement disturbs the system and alerts Cadmus and mission control that someone might be listening. If the connection can’t be secured, Cadmus can abort communication, saving his precious information and ensuring that malicious puppies don’t send him spam mail.
Though QKD is in an early developmental phase, it isn’t exactly “new.” It was proposed in the 1970s and has been worked on ever since. Only recently, though, has NASA taken steps into application of the technology for potential use in space. I spoke with experts from a few of the NASA centers to see what they’re up to. These early steps in quantum communications technologies might lead us to an un-hackable future where Cadmus is worry-free.
First, Evan Katz from Glenn Research Center in Cleveland, Ohio.
EVAN KATZ
My name is Evan Katz and I am an optical communications researcher at Glenn Research Center. My role is to characterize and test novel optical quantum communication devices that would be applicable for space. Also, I've been working to determine how these technologies can be integrated into a future quantum communication network.
So the quantum laboratory at Glenn Research Center was established in 2000. And since that time, the Glenn research team has been working to increase the technology readiness of key space-based quantum communication components. So, some of these components consist of superconducting single-photon detectors, waveguide entanglement sources, coherent pulse sources, as well as quantum memory. Also, the research team here at Glenn Research Center has been performing architecture studies for next-generation quantum communication networks.
NARRATOR
Next, Dimitri Antsos from the Jet Propulsion Laboratory in Pasadena, California.
DIMITRI ANTSOS
My name is Dimitrios Antsos and I run a technology program that does research into future spacecraft telecommunications-related technologies to enhance the amount of data and the throughput that we can obtain from spacecraft in the future.
There's several areas of application of quantum communications. One is by modulating the quantum properties of the wave as well, for the same amount of power — so for the same cost, from the standpoint of the spacecraft, because a spacecraft typically is very power-constrained, and power is a consumable, it costs something — so, for the same amount of power imparted onto a wave, the hope is, you'll be able to transmit more information to the other end — the other end often being Earth.
And so the utility of the spacecraft is tremendously increased, depending on how much you can increase this amount of information called throughput or sometimes capacity.
NARRATOR
Finally, Harry Shaw from Goddard Space Flight Center in Greenbelt, Maryland.
HARRY SHAW
My name is Dr. Harry Shaw and I am a staff engineer in the telecommunications and networks technologies branch assigned to the Space Network project. So, I'm part of the team responsible for the Tracking and Data Relay Satellite constellation and I also conduct a variety of research activities in both theoretical and applied sciences, using my background in a wide area of science and engineering.
So if you imagine that communications relies essentially on a dictionary of codes, much like language relies on dictionaries of alphabets or pictograms, then quantum communication greatly expands that dictionary and that can result in more efficient communications or higher speed communications or more secure communications. And if you add quantum entanglement to the discussion, that expansion grows even larger.
So Goddard has a lot of projects in quantum computing, communications and sensing — and it's a long list — but my group is concentrating on developing practical quantum communications for space. And I work collaborating with universities. In some research we're leveraging Goddard’s capabilities in classical laser communications. In other research we're searching for materials that will support various forms of quantum communications.
And we are also concentrating on providing a pathway for student interns to get involved in quantum information theory, quantum communications and planning quantum communications missions.
NARRATOR
QKD won’t just impact space exploration. Imagine the effect the technology could have on Earth. This and other types of quantum encryption could potentially eliminate hacking; eliminate identity theft; eliminate many kinds of fraud. QKD could usher in a future where data can truly be secure.
Nasser Barghouty serves as the quantum science and technology lead for the Space Communications and Navigation program at NASA. He has some big plans for the future of quantum communications research.
NASSER BARGHOUTY
The benefits — at least theoretically — are amazing. One, the bandwidth: you will have increased bandwidth: how much information you can actually transmit, will just go through the roof. It will revolutionize how much information you can [send].
It’s like high-definition TV required more bandwidth than low-definition TV and so on. Color TV requires more bandwidth than black-and-white TV. So, imagine if we have no limitation on the bandwidth. What kind of TV are you going to have? It’s just crazy, right?
So that’s in the bandwidth and resolution and sensitivity.
On security, at least in theory — and currently the quantum systems are secure, or the quantum channel will be secure — if anybody is trying to mess with it, interfere with it, it will register. It will never not be undetected.
In quantum mechanics — counterintuitive — if you are observing — and to observe something you have to interact with it — you are changing it. And if you change something in the communication channel, I know it’s been messed with. So it’s no longer a valid something — information.
So it is what theoreticians in this field call, “provably secure.” You can prove this is 100% secure mathematically and that is an amazing advantage.
The vision of SCaN is to demonstrate, in the foreseeable future, certain quantum technology that we believe, and experts believe, would become — is critical for a future quantum network. What is that quantum technology that I must test?
There’s some obvious ones and some less obvious ones. And the field is being new — quantum information science itself is fairly new. The idea is to bring subject matter experts, some program directors and executives to actually zoom in on what exactly — just to be efficient and expedient — what exactly needs to be tested for our purposes.
It will bring together national experts, and their recommendation to NASA SCaN would be, “If you were to go into space, maybe you should test one, two, three.” And we will act on this.
So it will be a vetting of what technology demonstration would look like for a future quantum network in space.
NARRATOR
The quantum world is full of curiosities, rife with possibilities. It may not open us to faster-than-light communications, but it does open us to technologies that read like the most riveting science fiction.
Many NASA offices are littered with science fiction paraphernalia. Star Trek posters abound. Star Wars figurines serve as bookends for binders full of technical documentation. Amidst serious science, you find whimsy.
Writers inspire engineers and scientists. In turn, engineers and scientists inspire writers. Award-winning visual effects supervisor from the Star Trek series, Dan Curry, explains this relationship.
DAN CURRY
To me the most important thing scientists can get from science fiction is inspiration — a dream, a “what if?” And a lot of times, scientists are so focused on fact and reality and exploring things based on real knowledge that it can be useful to them to have somebody dream way far away or way out of the box and say, “Wow, that's an interesting idea. What if?” And then they might pursue a line of research based on that on that dreamer’s dream — like Arthur C. Clarke imagined orbiting communication satellites.
All science fiction has to be successful in reality. So, as we learn new things, science fiction must change — just like when we learned there was no atmosphere on the Moon, then science fiction realized we need spacesuits.
I can remember seeing that first photograph of the Earth taken by the Apollo 11 astronauts. And you see the lunar landscape in the foreground and you see Earth floating in space — and only the most perceptually challenged individuals would not conclude that we have a very special jewel in space, maybe the only place where life can exist as we know it.
I think that inspiration changed how we depict planets. If you look at early science fiction films like the great George Powell films, you could tell Earth was a painting and it didn't look very realistic.
And then the great work of the artist Chesley Bonestell should not be underestimated. He was a science fiction illustrator — and his work influenced a lot of people — and his attempts to make things look as real — I think opened the door for regular citizens to realize, “We do have access to space and it can be real and this stuff looks like we can readily accomplish it.”
NARRATOR
We look to science for the marvels of today. We look to science fiction for visions of the future, dreams like the ansible. At their intersection is the work of forward-thinking engineers and scientists, pursuing technologies far ahead of their time.
We don’t need infusions of imaginary alien technology to make the communications networks of tomorrow a reality. We have the knowledge, expertise and imagination to make science fiction into science fact. Faster-than-light communications might not be a possibility now — our current understanding of the natural laws that bind us don’t allow for it.
But who (or what) knows… maybe one day.
…
This season of “The Invisible Network” debuted in November of 2019. The podcast is produced by the Space Communications and Navigation program, or SCaN, out of Goddard Space Flight Center in Greenbelt, Maryland. Episodes were written and recorded by me, Danny Baird, with editorial support from Matthew Peters. Our public affairs officers are Peter Jacobs of Goddard’s Office of Communications, Clare Skelly of the Space Technology Mission Directorate and Kathryn Hambleton of the Human Exploration and Operations Mission Directorate.
Special thanks to Barbara Adde, SCaN Policy and Strategic Communications director, Rob Garner, Goddard Web Team lead, Amber Jacobson, communications lead for SCaN at Goddard, and all those who have leant their time, talent and expertise to making “The Invisible Network” a reality. Be sure to rate, review and subscribe to the show wherever you get your podcasts. For transcripts of the episodes, visit NASA.gov/invisible. To learn more about the vital role that space communications plays in NASA’s mission, visit NASA.gov/SCaN.
Last Updated: Dec. 19, 2019
Editor: Rob Garner
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