a thoughtful web.
Good ideas and conversation. No ads, no tracking.   Login or Take a Tour!
comment by ixnar
ixnar  ·  2137 days ago  ·  link  ·    ·  parent  ·  post: The 'impossible' EmDrive Thruster has received its first peer-reviewed paper

My bet is on this being a measurement error, or an extra force they didn't think about.

I e-mailed the main guy behind the paper and pointed out that they too easily disregard the possibility of this being an electrostatic effect because they say that can't be the case because the setup is "grounded". The air quotes are because I'm working on an electrostatic instrument, and our experience is that it is very hard to remove all surface charges. At the kind of forces this paper talks about it doesn't take much charge buildup for some nearby electric field to contribute force via Coulomb attraction. Any kind of grease stain or oxide patch can do this





user-inactivated  ·  2137 days ago  ·  link  ·  
This comment has been deleted.
ixnar  ·  2135 days ago  ·  link  ·  

Yep, this is why experimentalists have a bit of disdain for theoreticians

Devac  ·  2137 days ago  ·  link  ·  
This comment has been deleted.
ixnar  ·  2135 days ago  ·  link  ·  

One way to test it is to apply a static field and do some sweeps, maybe +-1/10/100/1000 V/m. Just insert some metal sheets in the chamber and apply a voltage

I'm working on a blog post about this, might have to draw some sketches

Devac  ·  2135 days ago  ·  link  ·  
This comment has been deleted.
ixnar  ·  2135 days ago  ·  link  ·