The Future of Physics: Entanglements and Wormholes

worm_holeQuantum entanglements are one of the most bizarre aspects of quantum physics, so much so that Albert Einstein himself referred to it as “spooky action at a distance.” Basically, the concept involves two particles with each occupying multiple states at once. Until such time as one is measured, neither has a definite state, causing the other particle to instantly assume a corresponding state, even if they reside on opposite ends of the universe.

But what enables particles to communicate instantaneously – and seemingly faster than the speed of light – over such vast distances? Earlier this year, physicists proposed an answer in the form of “wormholes,” or gravitational tunnels. The group showed that by creating two entangled black holes, then pulling them apart, they formed a wormhole connecting the distant black holes.

quantum-entanglement1Now an MIT physicist has found that, looked at through the lens of string theory, the creation of two entangled quarks — the very building blocks of matter — simultaneously gives rise to a wormhole connecting the pair. The theoretical results bolster the relatively new and exciting idea that the laws of gravity that hold the universe together may not be fundamental, but may arise from quantum entanglement themselves.

Julian Sonner, a senior postdoc at MIT’s Laboratory for Nuclear Science and Center for Theoretical Physics, published the results of his study in the journal Physical Review Letters, where it appears together with a related paper by Kristan Jensen of the University of Victoria and Andreas Karch of the University of Washington. Already, the theory is causing quite the buzz for scientists and fans of sci-fi who would like to believe FTL is still possible.

quantum_field_theoryThis is certainly good news for scientists looking to resolve the fundamental nature of the universe by seeing how its discernible laws fit together. Ever since quantum mechanics was first proposed more than a century ago, the main challenge for physicists has been to explain how it correlates to gravity. While quantum mechanics works extremely well at describing how things work on the microscopic level, it remains incompatible with general relativity.

For years, physicists have tried to come up with a theory that can marry the two fields. This has ranged from proposing the existence of a subatomic particle known as the “graviton” or “dilaton”, to various Grand Unifying Theories – aka. Theory of Everything (TOE) – such as Superstring Theory, Loop Quantum Gravity, and other theoretical models to explain the interaction. But so far, none have proven successful.

gravity_well_cartography_2_by_lordsong-d5lrxwsA theory of quantum gravity would suggest that classical gravity is not a fundamental concept, as Einstein first proposed, but rather emerges from a more basic, quantum-based phenomenon. In a macroscopic context, this would mean that the universe is shaped by something more fundamental than the forces of gravity. This is where quantum entanglement could play a role.

Naturally, there is a problem with this idea. Two entangled particles, “communicating” across vast distances, would have to do so at speeds faster than that of light — a violation of the laws of physics, according to Einstein. In July, physicists Juan Maldacena of the Institute for Advanced Study and Leonard Susskind of Stanford University proposed a theoretical solution in the form of two entangled black holes.

big bang_blackholeWhen the black holes were entangled, then pulled apart, the theorists found that what emerged was a wormhole – a tunnel through space-time that is thought to be held together by gravity. The idea seemed to suggest that, in the case of wormholes, gravity emerges from the more fundamental phenomenon of entangled black holes. Following up on work by Jensen and Karch, Sonner has sought to tackle this idea at the level of quarks.

To see what emerges from two entangled quarks, he first generated entangled quarks using the Schwinger effect — a concept in quantum theory that enables one to create particles out of nothing. Sonner then mapped the entangled quarks onto a four-dimensional space, considered a representation of space-time. In contrast, gravity is thought to exist in the fifth dimension. According to Einstein’s laws, it acts to “bend” and shape space-time.

black_holeTo see what geometry may emerge in the fifth dimension from entangled quarks in the fourth, Sonner employed holographic duality, a concept in string theory. While a hologram is a two-dimensional object, it contains all the information necessary to represent a three-dimensional view. Essentially, holographic duality is a way to derive a more complex dimension from the next lowest dimension.

Using holographic duality, Sonner derived the entangled quarks, and found that what emerged was a wormhole connecting the two, implying that the creation of quarks simultaneously creates a wormhole between them. More fundamentally, the results suggest that gravity itself may emerge from quantum entanglement. On top of all that, the geometry, or bending, of the universe as described by classical gravity, may also be a consequence of entanglement.

quantum-entanglement3As Sonner put it in his report, the results are a theoretical explanation for a problem that has dogged scientists who quite some time:

There are some hard questions of quantum gravity we still don’t understand, and we’ve been banging our heads against these problems for a long time. We need to find the right inroads to understanding these questions… It’s the most basic representation yet that we have where entanglement gives rise to some sort of geometry. What happens if some of this entanglement is lost, and what happens to the geometry? There are many roads that can be pursued, and in that sense, this work can turn out to be very helpful.

Granted, the idea of riding wormholes so that we, as humans, can travel from one location in space to another is still very much science fiction, knowing that there may very well be a sound, scientific basis for their existence is good news for anyone who believes we will be able to “jump” around the universe in the near to distant future. I used to be one of them, now… I think I might just be a believer again!

USS_Enterprise_caught_in_artificial_wormhole-640x272Sources: web.mit.edu, extremetech.com

The O’Neill Cylinder

Welcome all to another post that explores the world of conceptual sci-fi! In keeping with the trend of explaining concepts which helped inspire my group’s most recent project, the space colonization story Yuva, I’ve decided to talk about what is known as an O’Neill Cylinder.

Named in honor of Gerard K. O’Neill in his 1976 book The High Frontier: Human Colonies in Space, the concept deals with the idea of placing a large cylinder in space that would rotate to provide gravity. Habitats within the cylinder would be built along the walls to ensure uniform gravity.

Some of the more interesting features of this design, aside from the curious layout, is the fact that in such a setting, windows placed in the hull can provide natural illumination, thus cutting down on the electricity bill. If the cylinder is particularly large, in which case one side is invisible to the other, then the rotation can provide periodic light, simulating day and night. And being a single volume of space, it can be pressurized, the gravity increasing pressure near the surface.

Fans of Rendezvous with Rama will recognize this concept right off the bat. The alien vessel in the story, dubbed Rama, was one big O’Neill Cylinder that floated through space, with a city built directly into the interior. A circular lake was also placed at the midway point, known as the Cylindrical Sea. At the far ends of the ship, an entrance and a gravitational drive were placed.

Another example is to be found in the Gibson novel Neuromancer, where a space station known as “Freeside” became the focal point in part III of the story. According to Gibson’s own descriptions, the station was a large cylinder in space owned by the Tessier-Ashpool clan. Their own villa was located at the very tip, a place known as “Straylight”, with luxury apartments, hotels, and vacation spots lining the interior. Artificial illumination was provided by a long band that ran down the middle and obscured a clear view of the other side.

And last, and my personal favorite, is the eponymously named space station of Babylon 5. Built along the same lines as Rama and Freeside, this space station was one giant rotating cylinder which housed over a quarter million humans and aliens. The interior surface was divided between several sectors, each one coded by color.

B5_interiorBrown Sector was designated for trade facilities, Blue Sector for personnel facilities, Green for diplomats, Gray for manufacturing, Red for resident habitation, and Yellow for environmental control. Transport along the length of the station was handled by a long rail that was frequented by a transport shuttle. At this point in the station, the gravity was virtually nil and atmospheric pressure was also substantially less.

All of this was consistent with an O’Neill Cylinder and applied to far more than just the station itself. Just about all Earth ships and installations in the B5 universe contained rotating sections to provide gravity since humanity had not yet stumbled onto the secret of artificial gravity.

When it comes right down to it, the concept of a rotating space cylinder is a very eloquent idea for simulating gravity, consistent with hard science and realism. Artificial gravity is often used in science fiction as a sort of given, mainly because its convenient and simpler from a design standpoint. Ships that have cylinders and rotation sections are bulky compared to sleek, unrealistic space concepts – space barges compared to flying works of art.

But that’s really not realistic, especially where near-future science fiction is concerned. Like it or not, artificial gravity just isn’t a plausible concept yet, not unless we find that troublesome graviton particle and learn how to harness it in a stable way. Which is why you can tell that a franchise is particularly inspired when you see ships and stations relying on rotation sections to simulate gravity. Not only is it more realistic, its shows that the conceptual artists and writers are doing their homework.

And that’s precisely why the Yuva ships feature them! And I hope people will find that it is indicative of the kind of mindset me and my group have. We like sci-fi, we like realism, and its especially good when hard science and hard fiction come together. Can’t wait until the book is done, all these teasers are driving me nuts!

Higgs Boson, by Sheldon Cooper!

In honor of the recent news about the discovery of the Higgs Boson, I thought I’d post this funny clip from the Big Bang Theory. In it, Dr. Sheldon Cooper (who I swear is a friend of mine in disguise) tries to use it as the keyword in a game of charades. Not only is this one of my favorite shows around (it speaks to me!), they also manage to sneak in a fair bit of real science from time to time. Heck, if it weren’t for them, I never would have been sent scrambling to my laptop to look up the concept of “Loop Quantum Gravity”.

It almost makes we want to write about real science, unrelated to fiction and literature and such. Articles dedicated to the graviton, neutrinos, Relativity, and the mysteries of space and time. But then again, who has that kind of time, who would want to read it, and most importantly, would I really get any enjoyment out of writing about all that stuff? After all, I’m a geek, not a nerd 🙂

Enjoy!