Helical engine

Recently an engineer from NASA published an independent research (that is, without affiliation with the space agency) in which he addresses an idea of ​​a new type of engine, which could reach a speed up to 99% that of light (approximately 300 million meters per second). The person responsible for publishing the article, posted on NASA's own portal, is David Burns. In interviews, Burns admitted the existing difficulties for the realization of the new engine and stated that his independent research may contain some theoretical errors, which would need to be reviewed by specialists in the subjects discussed. Since the early 2000s, a special engine (also theoretical) had been proposed by Roger Shawyer. The referred engine would not need propellant (fuel) and was called “EM drive” (electromagnetic engine). In short, the engine is based on the idea of ​​trapping and reflecting radio waves inside a cavity, in order to produce a thrust to propel the rocket. Currently, this model is still widely discussed, having several test studies been carried out. The engine proposed by Burns would not use propellant and would be able, in vacuum, to gradually reach a speed close to that of light (not being a “leap” as seen in films like Star Wars). The engineer started explaining his idea from a mental experiment (image 2), constituded of a box with a weight and two springs at the ends of the box. The weight is then directed to one of the springs, say, the one on the right and, by hitting the right end of the box, it would shift to the right, whereas the weight is now going towards the spring on the left (by the third Newton's law (law of action-reaction)), causing, again, a displacement, but this time in the opposite direction (left), and so on. In the situation described, the box would have no real displacement, since the amount displaced to one side would be counterbalanced by the action of the weight on the other. However, Burns circumvented this problem by proposing a replacement of the weight in the mental experiment with a “tiny particle accelerator” organized in a non-linear, helix-shaped structure. In order to understand Burns' idea, it is essential to have a basic understanding of the special theory of relativity, since the thrust of the referred engine is linked to relativistic phenomena. When a particle is accelerated to a speed considerably close to that of light, it starts to suffer relativistic effects, so that the higher the speed, more the mass of the particle increases. The engine, with the use of electromagnets, would fire ions (alpha particles as proposed in the article) at very high speeds and, given the helix structure, the ions would be stripped in such a way that when they had maximum speed (greater mass) they would reach one side, generating , thus, a displacement (analogous to the mental experiment with weight), then the particle would be decelerated (with its mass decreased as a consequence) which results in a smaller “impact” on the opposite side (less displacement), that is, the net displacement, at the end of the cycle, is not null. In other words, in the physical description, the purpose of the helical motor is to increase the difference between linear momenta between collisions in both directions. The resulting thrust would then be able to propel the rocket up to an incredible speed of 0.99c (99% of the speed of light). Among some difficulties encountered in the in-depth development of the helical engine are the facts of experiments on Earth requiring more extensive conditions than in the vacuum of space (tests here would require a 200 meter long and 12 meter wide tube) and 65 megawatts of power (enough to keep a 440-liter refrigerator with freezer running daily for more than 2.5 years) to generate a 1 Newton thrust (force equivalent to that applied to the buttons on a computer keyboard). If the idea were implemented, it would be possible to reach the Moon in 1.5 seconds, Mars in 12.5 minutes and the nearest star system (Alpha Centauri) in approximately 4.4 years. Even with such speed, interstellar travel would still be unreachable, considering the distances of millions of light years from the nearest galaxies to the Milky Way. One of the 2019 Nobel Prize winners in physics, Michel Mayor, commented on the impossibility for humanity to reach habitable planets, with the closest being a few tens of light years from Earth. Stephen Hawking himself worked on a project aimed at building a space probe, called "Star Chip", with extremely small size, with a candle powered by light. The probe's thrust would be generated from a beam of combined lasers coming from Earth, which would propel the spacecraft at 20% of the speed of light.

Despite being non-materialized concepts, such ideas provide a possibility of progress for humanity, providing foundations and a basis for new concepts and means of innovation and, who knows, maybe one day the difficulties of engineering will be overcome, making space travel a new fashion of transportation. One can illustrate the importance of innovative ideas with a phrase by Albert Einstein: “Whoever has never made mistakes has never tried anything new”. Reference material: "Short answers to big questions" (Stephen Hawking) https://ntrs.nasa.gov/search.jsp?R=20190029657 (link to David Burns' article) https://www.thesun.co.uk/tech/10137524/nasa-engineer-helical-engine-david-burns/ https://www.youtube.com/watch?v=JPsiC59NkNU&feature=youtu.be&fbclid=IwAR0PZgZhVTZKJ0-D3P_1XGIJvGBcrzWTIMP4KjTxWewcZWc3LKA2IU6I07M Photo 1: Classic photo of Han solo and Chewbacca getting ready for the "jump" at the speed of light. Photo 2: Illustration of the proposed mental experiment. Photo 3: David Burns