Future Fantastica
Teleportation
"
Beam me up scotty" captain Kirk says to his engineer and in a flash he is teleported from the distant planet to his ship! Wow! That was really some concept back then. "Back then? Whaddya mean ???", you ask. Okay. Let me explain.Two years ago an international group of six scientists confirmed the intuitions of science fiction writers by showing that perfect teleportation is indeed possible in principle, but only if the original is destroyed. Teleportation is the name given by science fiction writers to the feat of making an object or person disintegrate in one place while a perfect replica appears somewhere else. The general idea seems to be that the original object is scanned in such a way as to extract all the information from it, then this information is transmitted to the receiving location and used to construct the replica, not necessarily from the actual material of the original, but perhaps from atoms of the same kinds, arranged in exactly the same pattern as the original. A teleportation machine would be like a fax machine, except that it would work on 3-dimensional objects as well as documents, it would produce an exact copy rather than an approximate facsimile. Meanwhile, other scientists are planning experiments to demonstrate teleportation in microscopic objects, such as single atoms or photons, in the next few years. But science fiction fans will be disappointed to learn that no one expects to be able to teleport people or other macroscopic objects in the foreseeable future, for a variety of engineering reasons, even though it would not violate any fundamental law to do so. Until recently, teleportation was not taken seriously by scientists, because it was thought to violate the uncertainty principle of quantum mechanics, which forbids any measuring or scanning process from extracting all the information in an atom or other object. According to the uncertainty principle, the more accurately an object is scanned, the more it is disturbed by the scanning process, until one reaches a point where the object’s original state has been completely disrupted, still without having extracted enough information to make a perfect replica! This sounds like a solid argument against teleportation: if one cannot extract enough information from an object to make a perfect copy, it would seem that a perfect copy can not be made. But the six scientists found a way to make an end-run around this logic, using a celebrated and paradoxical feature of quantum mechanics known as the Einstein-Podolsky-Rosen effect. In brief, they found a way to scan out part of the information from an object A, which one wishes to teleport, while causing the remaining, unscanned, part of the information to pass, via the Einstein-Podolsky-Rosen effect, into another object C which has never been in contact with A. Later, by applying to C a treatment depending on the scanned-out information, it is possible to maneuver C into exactly the same state as A was in before it was scanned. A itself is no longer in that state, having been thoroughly disrupted b the scanning, so what has been achieved is teleportation, not replication.
(A bit bouncer huh?) — Yash
Superluminal Travel
E=mc². Probably the world’s most renowned equation is also the one which prohibits any matter in this universe to attain speeds faster than light. Until scientists (who else???) started working on theories of hypothetical particles called tachyons which supposedly traveled at superluminal speeds.
In the last decade, instances of superluminal travel have been positively and verifiably identified, mostly in the field of quantum mechanics and quantum barrier penetration. What are the problems associated with going faster than light? One easy explanation is called the "Treaty of Shalimar". Assume for instance that the Klingons and the Federation sign a treaty in which the Klingons promise peace in exchange for access to the Federation’s Technical Information Database (TID). The Federation leaves to take the treaty back to their home world at a speed of 0.6c. This gives the Klingons time to access the TID and develop a faster-than-light ship called the "slaughtering Super". They then send the Super to destroy the Federation ship. As it travels toward the ship, it destroys two bases along the way. These bases try to warn the ship, but of course any signal that they have can only travel at the speed of light which the Super easily outruns. The Super then gets to the negotiator’s ship and destroys it, destroying all evidence of any treaty and throwing the Klingon nation and the Federation back into war. The problem comes in when one looks at this sequence of events from the Federation’s point of view. The negotiators sign the treaty at Shalimar, and take off. The next event that they see is their own destruction. If they had remained alive after this, they would have next seen event 2, then event 1, and then watched the Super be disassembled. Scientists concluded from arguments like this that there is a basic Law of Causality which states that if A and B are two events which are causally related (A causes B), there will be no frame of reference in which B happens before A. There can not be a slaughtering Super, Or from the Federation’s point of view, it would destroy the Federation ship before it was even created. Since realizing the possibilities of superluminal travel, scientists have been developing theories and thought experiments for the testing of faster-than-light phenomena.These phenomena include the end of a search light beam, the shadow of a planet, and an oscilloscope trace beam. As the massless end of the searchlight beam sweeps across the sky, the tip can theoretically move faster than light.A shadow is like a negative search light beam. If a planet orbiting close to the sun, casts a shadow on a distant planet, the shadow flies across with superluminal speed. Then, there is the Techtronix 7104 oscilloscope. The electron trace beam sweeps across the screen at a measured .6c. If the display tube’s length were doubled, it would have an effective writing speed of 1.2c!After considering the possibility of motion faster than light, it’s concluded that Einstein Causality does not allow for the superluminal transmission of any useful information. However, conclusive evidence is given for faster-than-light transmission of smoothly varying functions such as that of a particle wave packet. This means that it is indeed possible for an object to have a velocity greater than that of light. --Yash
