Space Engine Google Drive Download
Kacey Lazzari
One of the ultimate dreams of humans everywhere is limitless, free energy. It's the ability to do the impossible: to pull power out of empty space itself; to create a device that spins faster-and-faster without an energy source; to accelerate a rocket without any fuel or propellant. Yet the laws of physics have always stood in the way.
A few years ago, a few renegade inventors emerged with another incarnation of this idea, in the form of a device called an EmDrive. This electromagnetic cavity claimed to be an engine that required no fuel and emitted no exhaust. It simply required input power, and could convert that energy into thrust. This would violate the laws of physics, but the experiments seemed to indicate that it worked.
A few years ago, an inventor named Roger Shawyer claimed to have invented a working prototype of exactly such a reactionless engine. The EmDrive, short for electromagnetic drive, claimed that by setting up a resonant cavity filled with photons, where one end of the cavity was narrower than the other, you would produce a net thrust, even without any exhaust. According to Shawyer and others, these devices did, indeed, produce a small but nonzero thrust, without any detectable form of exhaust.
Science never ends, and this paper, as compelling as it is, will surely not be the last word on the topic. Many will continue to research it, build prototypes, and search for thrust signatures without any exhaust: an action without a reaction. It may yet be possible, under some hitherto undiscovered conditions, that the action-reaction law is violated at some level. But the EmDrive probably isn't it. Pushing against the electromagnetic fields generated by your own electrical wires isn't a violation of action-reaction, and cannot power a spaceship. The EmDrive was billed as an "impossible" space drive, seeming too good to be true. Verification is always required, as is the complete elimination of systematic errors. As humans, we may be easily fooled, but to fool nature is not so simple. It looks like perpetual motion, as it always has been, is still just an impossible dream of ours.
The EmDrive is a concept for a thruster for spacecraft, first written about in 2001.[2][3][4][5] It is purported to generate thrust by reflecting microwaves inside the device, in a way that would violate the law of conservation of momentum and other laws of physics.[6][7][8][9][10] The concept has at times been referred to as a resonant cavity thruster.[11][12]
Rocket engines operate by expelling propellant, which acts as a reaction mass and which produces thrust per Newton's third law of motion. All designs for electromagnetic propulsion operate on the principle of reaction mass. A hypothetical drive which did not expel propellant in order to produce a reaction force, providing thrust while being a closed system with no external interaction, would be a reactionless drive, violating the conservation of momentum and Newton's third law.[17] Claims that a drive is reactionless are generally considered by physicists to be pseudoscience.[13]
The first design of a resonant cavity thruster claiming to be a reactionless drive was by Roger Shawyer in 2001. He called his conical design an "EmDrive", and claimed that it produced thrust in the direction of the base of the cone. Guido Fetta later built a "Cannae Drive", based in part on Shawyer's concept,[18][17] using a pillbox-shaped cavity.
Media coverage of experiments using these designs has been polarized. The EmDrive first drew attention, both credulous and dismissive, when New Scientist wrote about it as an "impossible" drive in 2006.[29] Media outlets were later criticized for misleading claims that a resonant cavity thruster had been "validated by NASA"[30] following White's first tentative test reports in 2014.[31] Scientists have continued to note the lack of unbiased coverage.[32]
In May 2018, researchers from the Institute of Aerospace Engineering at Technische Universität Dresden, Germany, concluded that the dominant effect underlying the apparent thrust could be clearly identified as an artifact caused by Earth's magnetic field interacting with power cables in the chamber, a result that other experts agree with.[37][38][14]
When power flows into the EmDrive, the engine warms up. This also causes the fastening elements on the scale to warp, causing the scale to move to a new zero point. We were able to prevent that in an improved structure. Our measurements refute all EmDrive claims by at least 3 orders of magnitude.[1]
In October 2006, Shawyer claimed to have conducted tests on a new water-cooled prototype with increased thrust.[41] He reported plans to have the device ready to use in space by May 2009 and to make the resonant cavity a superconductor,[41] neither of which materialized.
It is a fair criticism that New Scientist did not make clear enough how controversial Roger Shawyer's engine is. We should have made more explicit where it apparently contravenes the laws of nature and reported that several physicists declined to comment on the device because they thought it too contentious ... The great thing is that Shawyer's ideas are testable. If he succeeds in getting his machine flown in space, we will know soon enough if it is ground-breaking device or a mere flight of fancy.[29]
As I read it, I, like the thousands of other physicists who will have read it, immediately realised that this was impossible as described. Physicists are trained to use certain fundamental principles to analyse a problem and this claim clearly flouted one of them ... The Shawyer drive is as impossible as perpetual motion. Relativistic conservation of momentum has been understood for a century and dictates that if nothing emerges from Shawyer's device then its centre of mass will not accelerate. It is likely that Shawyer has used an approximation somewhere in his calculations that would have been reasonable if he hadn't then multiplied the result by 50,000. The reason physicists value principles such as conservation of momentum is that they act as a reality check against errors of this kind.[43]
In 2007, the UK Department of Trade and Industry granted SPR an export license to Boeing in the US.[44] According to Shawyer, in December 2008 he was invited to present on the EmDrive, and in 2009 Boeing expressed interest in it,[45] at which point he stated that SPR built a thruster which produced 18 grams of thrust, and sent it to Boeing. Boeing did not license the technology and communication stopped.[46] In 2012, a Boeing representative confirmed that Boeing Phantom Works used to explore exotic forms of space propulsion, including Shawyer's drive, but such work later ceased. They confirmed that "Phantom Works is not working with Mr. Shawyer," nor pursuing those explorations.[18]
In 2014, Shawyer presented ideas for 'second-generation' EmDrive designs and applications at the annual International Astronautical Congress. A paper based on his presentation was published in Acta Astronautica in 2015.[47] While no functional prototype of the first-generation drive had yet been produced, it described a model for a superconducting resonant cavity and three models for thrusters with multiple cavities.
The Cannae Drive (formerly Q-drive),[50] is another implementation of this idea, with a relatively flat cavity rather than a truncated cone. It was designed by Fetta in 2006 and promoted within the US through his company, Cannae LLC, since 2011.[50][51][52][53][54] In 2016, Fetta announced plans to eventually launch a CubeSat satellite containing a version of the Cannae Drive, which would run for 6 months to observe how it functions in space.[55] No followup was published.
In 2008, a team of Chinese researchers led by Juan Yang (杨涓), professor of propulsion theory and engineering of aeronautics and astronautics at Northwestern Polytechnical University (NWPU) in Xi'an, China, said that they had developed a valid electro-magnetic theory behind a microwave resonant cavity thruster.[19][78] A demonstration version of the drive was built and tested with different cavity shapes and at higher power levels in 2010. Using an aerospace engine test stand usually used to precisely test spacecraft engines like ion drives,[17][56][57] they reported a maximum thrust of 720 mN at 2,500 W of input power.[57] Yang noted that her results were tentative, and said she "[was] not able to discuss her work until more results are published".[17]
Since 2011, White had a team at NASA known as the Advanced Propulsion Physics Laboratory, or Eagleworks Laboratories, devoted to studying exotic propulsion concepts.[79] The group investigated ideas for a wide range of untested and fringe proposals, including Alcubierre drives, drives that interact with the quantum vacuum, and RF resonant cavity thrusters. In 2014, the group began testing resonant cavity thrusters, and in November 2016 they published a peer-reviewed paper on this work, in the Journal of Propulsion and Power.[22][80][81]
In August 2016, Cannae announced plans to launch its thruster on a 6U cubesat which they would run for 6 months to observe how it functions in space. Cannae formed a company called Theseus for the venture and partnered with LAI International and SpaceQuest Ltd. to launch the satellite. As of 2022, no launch date has yet been announced.[55]
The largest error source is believed to come from the thermal expansion of the thruster's heat sink; as it expands this would lead to a change in the centre of gravity causing the resonant cavity to move. White's team attempted to model the thermal effect on the overall displacement by using a superposition of the displacements caused by "thermal effects" and "impulsive thrust" with White saying "That was the thing we worked the hardest to understand and put in a box". Despite these efforts, White's team were unable to fully account for the thermal expansion. In an interview with Aerospace America, White comments that "although maybe we put a little bit of a pencil mark through [thermal errors]... they are certainly not black-Sharpie-crossed-out."[98]
35fe9a5643