NASA’s Proposed Warp-Drive Visualized

ixs-enterpriseIt’s no secret that NASA has been taking a serious look at Faster-Than-Light (FTL) technology in recent years. It began back in 2012 when Dr Harold White, a team leader from NASA’s Engineering Directorate, announced that he and his team had begun work on the development of a warp drive. His proposed design, an ingenious re-imagining of an Alcubierre Drive, may eventually result in an engine that can transport a spacecraft to the nearest star in a matter of weeks — and all without violating Einstein’s law of relativity.

In the spirit of this proposed endeavor, White chose to collaborate with an artist to visualize what such a ship might look like. Said artist, Mark Rademaker, recently unveiled the fruit of this collaboration in the form of a series of concept images. At the heart of them is a sleek ship nestled at the center of two enormous rings that create the warp bubble. Known as the IXS Enterprise, the ship has one foot in the world of science fiction, but the other in the realm of hard science.

ixs-enterprise-0The idea for the warp-drive comes from the work published by Miguel Alcubierre in 1994. His version of a warp drive is based on the observation that, though light can only travel at a maximum speed of 300,000 km/sec (186,000 miles per second, aka. c), spacetime itself has a theoretically unlimited speed. Indeed, many physicists believe that during the first seconds of the Big Bang, the universe expanded at some 30 billion times the speed of light.

The Alcubierre warp drive works by recreating this ancient expansion in the form of a localized bubble around a spaceship. Alcubierre reasoned that if he could form a torus of negative energy density around a spacecraft and push it in the right direction, this would compress space in front of it and expand space behind it. As a result, the ship could travel at many times the speed of light while the ship itself sits in zero gravity – hence sparing the crew from the effects of acceleration.

alcubierre-warp-drive-overviewUnfortunately, the original maths indicated that a torus the size of Jupiter would be needed, and you’d have to turn Jupiter itself into pure energy to power it. Worse, negative energy density violates a lot of physical limits itself, and to create it requires forms of matter so exotic that their existence is largely hypothetical. In short, what was an idea proposed to circumvent the laws of physics itself fell prey to their limitations.

However, Dr Harold “Sonny” White of NASA’s Johnson Space Center reevaluated Alcubierre’s equations and made adjustments that corrected for the required size of the torus and the amount of energy required. In the case of the former, White discovered that making the torus thicker, while reducing the space available for the ship, allowed the size of it to be greatly decreased – from the size of Jupiter down to a width of 10 m (30 ft), roughly the size of the Voyager 1 probe.

alcubierre-warp-drive-overviewIn the case of the latter, oscillating the bubble around the craft would reduce the stiffness of spacetime, making it easier to distort. This would reduce the amount of energy required by several orders of magnitude, for a ship traveling ten times the speed of light. According to White, with such a setup, a ship could reach Alpha Centauri in a little over five months. A crew traveling on a ship that could accelerate to just shy of the speed of light be able to make the same trip in about four and a half years.

Rademaker’s renderings reflect White’s new calculations. The toruses are thicker and, unlike the famous warp nacelles on Star Trek’s Enterprise, their design is the true function of hurling the craft between the stars. Also, the craft, which is divided into command and service modules, fits properly inside the warp bubble. There are some artistic additions, such as some streamlining, but no one said an interstellar spaceship couldn’t be functional and pretty right?

ixs-enterprise-2For the time being, White’s ideas can only be tested on special interferometers of the most exacting precision. Worse, the dependence of the warp on negative energy density is a major barrier to realization. While it can, under special circumstances, exist at a quantum level, in the classical physical world that this ship must travel through, it cannot exist except as a property of some form of matter so exotic that it can barely be said to be capable of existing in our universe.

Though no one can say with any certainty when such a system might be technically feasible, it doesn’t hurt to look ahead and dream of what may one day be possible. And in the meantime, you can check out Rademaker’s entire gallery by going to his Flickr account here. And be sure to check out the video of Dr. White explaining his warp-drive concept at SpaceVision 2013:


Sources:
gizmag.comIO9.com, cnet.com
, flickr.com

New Video: Quantum Entanglement Explained

quantum-entanglement1If you’re like most people, the concept of quantum entanglements confuses and perplexes you. But considering its important to quantum science, the future of computing and (maybe, just maybe) space travel, it’s something we should all strive to understand. Luckily, this educational video produced by PHD Comics, and narrated by physicists Jeff Kimble and Chen-Lung Hung, explains it in easy-to-understand terms.

To break it down succinctly, quantum entanglement is the unusual behavior where elementary particles become linked so that when something happens to one, something happens to the other; no matter how far apart they are. This bizarre behavior of particles that become inextricably linked together is what Einstein supposedly called “spooky action at a distance.”

Understanding how this works may very well unlock the mysteries of the universe, shedding light on the unusual behavior of black holes, how gravity interacts with the other fundamental forces and yielding a Grand Unifying Theory/Theory of Everything (TOE)- and even let us circumvent “natural” barriers like the speed of light. So enjoy the video, and be sure to listen carefully. Simplified or not, this is still some pretty heavy stuff!


Source: universetoday.com

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