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http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/

Evaluating NASA’s Futuristic EM Drive
April 29, 2015 by José Rodal, Ph.D, Jeremiah Mullikin and Noel Munson - subedited by Chris Gebhardt no alt
A group at NASA’s Johnson Space Center has successfully tested an electromagnetic (EM) propulsion drive in a vacuum – a major breakthrough for a multi-year international effort comprising several competing research teams. Thrust measurements of the EM Drive defy classical physics’ expectations that such a closed (microwave) cavity should be unusable for space propulsion because of the law of conservation of momentum.

EM Drive:

Last summer, NASA Eagleworks – an advanced propulsion research group led by Dr. Harold “Sonny” White at the Johnson Space Center (JSC) – made waves throughout the scientific and technical communities when the group presented their test results on July 28-30, 2014, at the 50th AIAA/ASME/SAE/ASEE Joint Propulsion Conference in Cleveland, Ohio.

Those results related to experimental testing of an EM Drive – a concept that originated around 2001 when a small UK company, Satellite Propulsion Research Ltd (SPR), under Roger J. Shawyer, started a Research and Development (R&D) program.

The concept of an EM Drive as put forth by SPR was that electromagnetic microwave cavities might provide for the direct conversion of electrical energy to thrust without the need to expel any propellant.

2015-04-19-005958This lack of expulsion of propellant from the drive was met with initial skepticism within the scientific community because this lack of propellant expulsion would leave nothing to balance the change in the spacecraft’s momentum if it were able to accelerate.

However, in 2010, Prof. Juan Yang in China began publishing about her research into EM Drive technology, culminating in her 2012 paper reporting higher input power (2.5kW) and tested thrust (720mN) levels of an EM Drive.

In 2014, Prof. Yang’s papers reported extensive tests involving internal temperature measurements with embedded thermocouples.

It was reported (in SPR Ltd.’s website) that if the Chinese EM Drive were to be installed in the International Space Station (ISS) and work as reported, it could provide the necessary delta-V (change in velocity needed to perform an on-orbit maneuver) to compensate for the Station’s orbital decay and thus eliminate the requirement of re-boosts from visiting vehicles. Despite these reports, Prof. Yang offered no scientifically-accepted explanation as to how the EM Drive can produce propulsion in space.

2015-04-19-010043Dr. White proposed that the EM Drive’s thrust was due to the Quantum Vacuum (the quantum state with the lowest possible energy) behaving like propellant ions behave in a MagnetoHydroDynamics drive (a method electrifying propellant and then directing it with magnetic fields to push a spacecraft in the opposite direction) for spacecraft propulsion.

In Dr. White’s model, the propellant ions of the MagnetoHydroDynamics drive are replaced as the fuel source by the virtual particles of the Quantum Vacuum, eliminating the need to carry propellant.

This model was also met with criticism in the scientific community because the Quantum Vacuum cannot be ionized and is understood to be “frame-less” – meaning you cannot “push” against it, as required for momentum.

The tests reported by Dr. White’s team in July 2014 were not conducted in a vacuum, and none of the tests reported by Prof. Yang in China or Mr. Shawyer in the UK were conducted in a vacuum either.

The scientific community met these NASA tests with skepticism and a number of physicists proposed that the measured thrust force in the US, UK, and China tests was more likely due to (external to the EM Drive cavity) natural thermal convection currents arising from microwave heating (internal to the EM Drive cavity).

However, Paul March, an engineer at NASA Eagleworks, recently reported in NASASpaceFlight.com’s forum (on a thread now over 500,000 views) that NASA has successfully tested their EM Drive in a hard vacuum – the first time any organization has reported such a successful test.

To this end, NASA Eagleworks has now nullified the prevailing hypothesis that thrust measurements were due to thermal convection.

我只想说，肯定是伪科学，也早已经有人用理论反驳了。而那些所谓实验验证，远远经不起推敲——明明是很荒谬的结果，一些人却在那里冥思苦想其“物理解释”。

我一直很反感内地为了抵制西方民主而编造的种种阴谋论，但是在这件事情上，我真的有些怀疑是不是一场阴谋：故意误导大陆的军事科技研究。由于涉密，导致欺骗科研经费之事有意无意地发生。如果是一般的非保密项目，早就被社会识破。

这跟水变油是一个货色。

我建议习JP让中纪委配合物理学家好好调查一下
（考虑到大陆特色，这里说的“物理学家”，是处于科研第一线的物理学家，不是一些欺名盗世的院士——是院士也行，必须是那些从未担任过任何行政职务的院士）

如果只是民间自娱自乐倒也无所谓，而实际上远非如此。当年水变油的事件不可重演，何况这种涉及国防事业的东西。

我只表达我个人看法，也许不足信。我只是抛砖引玉，开个头，希望其他人也参与本话题讨论。参与这个讨论，还真是能与“爱国”扯上关系的。

BTW，如果有对我前面某些说法感到莫名其妙的网友，请不要深问，谢谢！

这里有一篇反驳文章：
http://gregegan.customer.netspace.net.au/SCIENCE/Cavity/Cavity.html