Quote:
Originally Posted by xelasnave
The last time I looked the Pioneer anomoly was explained away due to heat radiating and causing acceleration in the dire tion of the Sun, I think thats the way it was put.
Is this new thing anyway simlilar?
Alex
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Yes, similar...
It seems in this case the thrust is due to "paired" photons that escape the resonant cavity.
The problem is, this way of propulsion is even less efficient than simple parabolic antenna fed with transmitter, because not all photons escape from resonant cavity (those trapped simply provide heating of the cavity walls due to losses).
If the measurement results are real (they still need to be confirmed by independent party me thinks), this will only be a interesting curiosity IMO, with very dubious application value... very far cry from "revolution in space flight", as some would like it to be.
See more here from paper:
https://www.reddit.com/r/EmDrive/com...he_exhaust_of/
New EM-Drive Paper: On the exhaust of electromagnetic drive
(http://www.helsinki.fi/~aannila/arto/emdrive.pdf)
The paper is written by Arto Annila, a Professor in Physics at the University of Helsinki, Erkki Kolehmainen, a Professor of Chemistry at the University of Jyväskylä and Patrick Grahn, an engineer with a specialization in COSMOL Multiphysics at the University of Helsinki.
The abstract to the paper notes:
" Recent reports about propulsion without reaction mass have been met with disbelief. Closed metal cavities, when fueled with microwaves, have delivered thrust without any apparent exhaust. Thus the Law of Action-Reaction seems to have been violated. We consider the possibility that the exhaust is in a form that has so far escaped both experimental detection and theoretical attention. In the thruster’s cavity microwaves interfere with each other and invariably some photons will also end up co-propagating with opposite phases. At the destructive interference electromagnetic fields cancel. However, the photons themselves do not vanish for nothing but continue in propagation. These photon pairs without net electromagnetic field do not reflect back from the metal walls but escape from the resonator. By this action momentum is lost from the cavity which, according to the conservation of momentum, gives rise to an equal and opposite reaction. We examine theoretical corollaries and practical concerns that follow from the paired –photon conclusion."