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

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

News From Space: Big Bang Vs. Black Hole

big bang_blackholeFor decades, the Big Bang Theory has remained the accepted theory of how the universe came to be, beating out challengers like the Steady State Theory. However, many unresolved issues remain with this theory, the most notable of which is the question of what could have existed prior to the big bang. Because of this, scientists have been looking for way to refine the theory.

Luckily, a group of theoretical physicists from the Perimeter Institute (PI) for Theoretical Physics in Waterloo, Ontario have announced a new interpretation on how the universe came to be. Essentially, they postulate that the birth of the universe could have happened after a four-dimensional star collapsed into a black hole and began ejecting debris.

big_bangThis represents a big revision of the current theory, which is that universe grew from an infinitely dense point or singularity. But as to what was there before that remain unknown, and is one of a few limitations of the Big Bang. In addition, it’s hard to predict why it would have produced a universe that has an almost uniform temperature, because the age of our universe (about 13.8 billion years) does not give enough time to reach a temperature equilibrium.

Most cosmologists say the universe must have been expanding faster than the speed of light for this to happen. But according to Niayesh Afshordi, an astrophysicist with PI who co-authored the study, even that theory has problems:

For all physicists know, dragons could have come flying out of the singularity. The Big Bang was so chaotic, it’s not clear there would have been even a small homogenous patch for inflation to start working on.

black_holeThe model Afshordi and her colleagues are proposing is basically a three-dimensional universe floating as a membrane (or brane) in a “bulk universe” that has four dimensions. If this “bulk universe” has four-dimensional stars, these stars could go through the same life cycles as the three-dimensional ones we are familiar with. The most massive ones would explode as supernovae, shed their skin and have the innermost parts collapse as a black hole.

The 4-D black hole would then have an “event horizon”, the boundary between the inside and the outside of a black hole. In a 3-D universe, an event horizon appears as a two-dimensional surface; but in a 4-D universe, the event horizon would be a 3-D object called a hypersphere. And when this 4-D star blows apart, the leftover material would create a 3-D brane surrounding a 3-D event horizon, and then expand.

planck-attnotated-580x372To simplify it a little, they are postulating that the expansion of the universe was triggered by the motion of the universe through a higher-dimensional reality. While it may sound complicated, the theory does explain how the universe continues to expand and is indeed accelerating. Whereas previous theories have credited a mysterious invisible force known as “dark energy” with this, this new theory claims it is the result of the 3-D brane’s growth.

However, there is one limitation to this theory which has to do with the nearly uniform temperature of the universe. While the model does explain how this could be, the ESA’s Planck telesceop recently mapped out the universe and discovered small temperature variations in the cosmic microwave background (CBM). These patches were believed to be leftovers of the universe’s beginnings, which were a further indication that the Big Bang model holds true.

big_bang1The PI team’s own CBM readings differ from this highly accurate survey by about four percent, so now they too are going back to the table and looking to refine their theory. How ironic! However, the IP team still feel the model has worth. While the Planck observations show that inflation is happening, they do not show why the inflation is happening.

Needless to say, we are nowhere near to resolving how the universe came to be, at least not in a way that resolves all the theoretical issues. But that’s the things about the Big Bang – it’s the scientific equivalent of a Hydra. No matter how many times people attempt to discredit it, it always comes back to reassert its dominance!

Source: universetoday.com, perimeterinstitute.ca

NASA Designing World’s First FTL

alcubierre-warp-drive-overviewA few months ago, physicist Harold White shocked and stunned the world when he announced that he and his team at NASA were beginning work on the world’s first faster-than-light warp drive. Naturally, this produced a whole slew of questions, not the least of which was what model his team would be considering. After all, there have been countless theories put forth over the years as to how humanity could one day break the “light barrier”. Which theory White and his team would pursue was naturally the first on everybody’s mind.

Apparently, White’s proposed design will be a re-imagining of the Alcubierre Drive, a concept which has already been extensively popularized in science fiction and pop culture. Proposed by Miguel Alcubierre in 1994 in his seminal paper: “The Warp Drive: Hyper-Fast Travel Within General Relativity,” Alcubierre suggested a mechanism by which space-time could be “warped” both in front of and behind a spacecraft. After going over the equations in detail, White believed he found a way to make the theory work.

All of this began in October of last year, where White was preparing for a talk he was to give as part of the kickoff of the 100 Year Starship project in Orlando, Florida. While putting together his presentation on warp, he began toying with Alcubierre’s field equations, mainly out of curiosity. After making some adjustments, he came to the conclusion that something truly workable was there, and presented his findings this past October in Atlanta, where the 100 Year Starship project was meeting once again.

alcubierre-warp-drive-overviewThe equations and theory postulates that since space-time can be contracted and expanded, empty space behind a starship could be made to expand rapidly, pushing the craft in a forward direction. Passengers would perceive it as movement despite the complete lack of acceleration, and vast distances (i.e. light years) could be passed in a matter of days and weeks instead of decades. What’s more, this “warp drive” would allow for FTL while at the same time remaining consistent with Einstein’s theory of Relativity.

This has been a major hurdle for physicists looking for ways around the speed of light, since all previous theories required a cosmic model where Relativity – fundamental to our understanding of the universe – would not apply. At the same time, the physics described in the Alcubierre process sound like something directly out of Star Trek, something all sci-fi geeks are sure to notice! It begins with a spheroid object being placed between two regions of space-time (one expanding and one contracting), which in turn generates a “warp bubble” that moves space-time around the object, effectively repositioning it.

The end result is faster-than-light travel without the spheroid having to move with respect to its local frame of reference. In short, those aboard the object would notice the repositioning of their spacecraft, but would experience no “time dilation”, where their perception of time differs greatly from those in a different frame of reference. Or to put it another way, the Alcubierre drive could transport people from Earth to Mars and back again, and for all concerned (the passengers and people Earthside) there would be little difference in the amount of time experienced. None of this, “I’m a year older, but everybody I knew is dead!” stuff. You have to admit, that’s a real perk!

But of course, there are a lot of challenges ahead for White and his team. For example, in an interview with IO9, White said: “Remember, nothing locally exceeds the speed of light, but space can expand and contract at any speed. However, space-time is really stiff, so to create the expansion and contraction effect in a useful manner in order for us to reach interstellar destinations in reasonable time periods would require a lot of energy.” Luckily, his reworking of the equations has brought that requirement done somewhat, but the amounts required mean that a great deal of research and development is still needed.

Perhaps if we can find a way to work cold fusion in the mix, or build an anti-matter reactor. Maybe some hydrogen ramscoops and a Heisenberg compensator, then we’d be in business! Might we need some dilithium crystals too? I’ll call Jordie LaForge and tell him to get on it! 😉

warp_drive

The Blue Martian Sunset

Ever since the Curiosity rover landed, NASA had been awash with new photos of the Martian landscape. Naturally, most have been black and white picks of the oxidized soil immediately around the rover’s landing area. But more have been arriving lately that show a feature unique to Mars. That feature is the Blue Sunset.

Scientists working for NASA claim that this phenomena is due to the particulate matter that is present in the Martian atmosphere. This red dust – which is composed of oxidized minerals, mainly iron – is what gives Mars its distinct color, but also provides for a fractal effect which shifts light towards the blue end of the spectrum. The same basic principle is true for sunsets seen from Earth, where our oxygen and nitrogen and ozone atmosphere causes the light to shift to the red end of the spectrum.

These patterns of Red Shift and Blue Shift are actually a very common element when it comes to astronomy. When observing galaxies in the night sky, scientists are able to tell that they are moving away because the light that they emit, and which is intercepted by our telescopes is shifted to the red end of the spectrum. Based on how much shift is occurring, scientists are bale to measure just how fast they are moving, relative to us.

When it comes time to hurl some objects into space ourselves, such as interstellar space craft, we can expect to see some of this close up. Out there, relativistic effects caused by high speeds will make the stars ahead of the ship look reddish, while stars seen to the rear will appear blue. Cool how that works huh?

To illustrate this Blue Sunset, NASA has released a compilation, time-elapse video which was taken two years ago by the Exploration Rover. It shows the sun setting in full, all the while emitting that cool, blue glow. Enjoy and stay tuned for more news on the Martian front!

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!