What Is a Warp Drive and a Warp Bubble, or the Key to FTL Travel Around the Universe
Anyone who has seen the show Star Trek knows that the starship Enterprise travels from one adventure to another using the warp engine, a device that allows FTL (faster than light) travel. However, people point out that such a feat should be impossible due to Einstein's Theory of Relativity, which states that nothing can travel faster than the speed of light. So is there any real science behind warp drive, or is it merely science fiction?
In theory, if one were to use a warp drive, it would involve bending space-time. According to the Theory of Relativity, space and time are woven together to form a space-time continuum in which everything exists. Anything that has mass rests on this, thus causing a dip in space-time we call gravity. The greater the gravity, the greater the dip is. Black holes, the remnants of a massive star, have so much gravity that they cause the fabric to rip in complex ways that we call a singularity, in which the activity is so complex that we cannot fully understand it with current physics.
The goal of warp drive, however, is not to rip the fabric but bend it, so that the distance between points A and B is easier to cross. In general, you need a way to generate a "warp bubble." This bubble would cause the space in front of the object to expand and the space behind it to contract. Through this bending of the fabric of space, we are not actually moving in a traditional sense! The space we are in remains the same, but the space around us is changing. Thus, our little pocket of space is moving, but we inside it do not. We can move faster than the speed of light because of this, for the space is moving and not something in space-time, and not violate Einstein.
The means to bend space-time, however, are not clear. You could create such a gravity well that it causes a rip in the fabric, but this is more in tune with subspace travel, in which you travel "underneath" the fabric of space. If you were to contract and expand space-time like in Star Trek, you could manipulate it to bend. How this would be achieved is unknown, but it is highly unlikely going to be by the means seen in Star Trek. No "warp cores" streaming a matter-antimatter explosion though dilithium crystals. Instead, we will need to rely on more achievable technology. But what could we have at our disposal that would allow us to accomplish this amazing feat?
Current Work on Warp Drives
In 1994, a paper entitled "The Warp Drive: Hyper-fast travel within General Relativity" was written by Miguel Alcubierre. He worked through plenty of higher-level math to show that warp drive was possible based off the space-bending principles mentioned above. The technology to build such a device is not possible currently, but is within our grasp. NASA is working on testing a key component: the "warp bubble," previously mentioned. To create such a field, you rely on what we call "negative energy," or what forms in the vacuum of space as a result of some quantum mechanical quirks. This property essentially states that as you disturb light in a vacuum, where nothing but space-time exists, you will generate this special type of energy. It is through this negative energy that space-time can be altered and possibly create a warp bubble, but it cannot currently be produced in large amounts and the quantity needed for such a bubble is prohibitive (you would need more exotic mass than the Universe contains) (Scharr).
Fortunately, after some revising of the original work, it was shown that all you need is a few kilograms instead. Another intriguing possibility is to use dark energy instead, which is quite abundant (almost 75% of the Universe is made of it) but no known ways of harvesting it are known. To add to the list of problems, no one knows how to control a warp bubble or even if it could be controlled once created. What happens if the bubble hits an object? We don't know. Also, some models indicate that black hole-like event horizons may be created, which would then mean Hawking radiation would be present (Dodson). No sweat, right?
To test out some properties, NASA is using special lasers in their facilities. One will be shined through a region of normal space with matter (as a control) and another through a vacuum. If light through the vacuum exits that region with a wavelength that has been red-shifted, or light that has lost energy, then we will know some of it was transformed into negative energy and possibly a warp bubble. Thus far no good data has been retrieved, mainly because of the sensitivity of the experiment have not been fully resolved (movements of the Earth will render the results null, any imperfections in the vacuum, etc.) (Scharr).
To see if the basic shape of the warp bubble can be created, NASA developed the White-Juday Warp Field Interferometer. A helium-neon laser will fire a beam that will; hit a splitter. One path will be the control and the other will pass in the middle of a torus, through the open center. The torus will have a high voltage that should mimic the warping effect. The apparatus will be able to see any shifts as small as a nanometer (Dodson). We eagerly await the results, of course.
Dodson, Brian. "Warp Drive Looks More Promising Than Ever In Recent NASA Studies." gizmag. Gizmag.com, 03 Oct. 2012. Web. 12 Dec. 2014.
Scharr, Julian. "Warp Drive Feasible? Relativity Loophole Means 'Star Trek' Device Might Actually Work, Physicists Say." The Huffington Post. TheHuffingtonPost.com, 14 May 2013. Web. 13 June 2013.http://www.huffingtonpost.com/2013/05/14/warp-drive-possible-star-trek-special-relativity_n_3273422.html?utm_hp_ref=physics
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© 2009 Leonard Kelley