/r/EmDrive

Photograph via snooOG

Welcome to /r/EmDrive

The EmDrive (also known as an RF resonant cavity thruster) is a purported reactionless propulsion technology, which would if true would revolutionize space travel and the world economy. However, sadly, it is a pseudoscientific fraud, also known as pathological science. After nearly 20 years since its "invention", there is no compelling empirical evidence that it works as described despite ample testing of a relatively simple design and all theoretical explanations for the so-called EmDrive effect being completely at odds with our most fundamental theoretical knowledge of physics.

Some interesting links for those who wish to learn more:

Wikipedia,

EmDrive.wiki

Snopes article on EmDrive

RationalWiki

Wikipedia page for Pathological Science

Wikipedia page for Pseudoscience

Why you shouldn't be excited about the recent EmDrive paper in AIAA Propulsion

And some overview YouTube videos: (1,2,3)

The r/EmDrive Rules of Participation:

This subreddit welcomes people of all backgrounds to participate in polite discourse about all things EmDrive and other radio frequency (RF) resonant cavity thrusters. We encourage scientists, builders, replicators, enthusiasts, believers, skeptics, and the like, to come together on the most active EmDrive sub and treat each other with civility. Polite banter will be tolerated. Impolite cruelty and name-calling will not.

Our full list of rules can be found here.

Please also abide by Reddit's policies:

https://www.reddit.com/help/contentpolicy/

https://www.reddit.com/wiki/reddiquette

In short: remember Wheaton's law.

Related subreddits: /r/skeptics /r/VXjunkies /r/AskScience /r/Science /r/physics

/r/EmDrive

12,064 Subscribers

1

CID vs Q Thruster: A Scientific Comparison

CID (Centrifugal Impulse Drive)

Operating Principle:

  • Uses classical electromagnetic and mechanical forces
  • Complete mathematical framework with measurable forces
  • No theoretical assumptions needed

Core Equations:

  • Net Force: F_net = -∇(m·B) + mω²r
  • Magnetic Field: B(r,t) = B₀(R/r)³[2cos(ωt)r̂ + sin(ωt)θ̂]
  • Centrifugal Force: F_c = mω²r
  • Efficiency: η = (F_net·v)/P

Demonstrated Performance:

  • Thrust: 0.313-0.46875 N
  • System Mass: 24.7 kg
  • Operating Speed: 150 RPM
  • Efficiency: 0.58%

Q Thruster

Operating Principle:

  • Based on quantum vacuum fluctuations
  • Relies on "quantum vacuum virtual plasma"
  • Requires unproven quantum effects

Theoretical Framework:

  • Incomplete mathematical model
  • Relies on speculative quantum vacuum effects
  • No peer-verified force generation mechanism

Claimed Performance:

  • Specific Thrust: 0.4-4.0 N/kWe
  • Thrust Range: 0.001-0.004 N (micro-Newtons)
  • Efficiency: Not publicly verified

Key Differences

CID:

  • Uses only known forces (magnetic and centrifugal)
  • Forces are measurable and reproducible
  • Works within established physics
  • No violation of conservation laws
  • Complete mathematical proof
  • Peer-review ready documentation

Q Thruster:

  • Requires unproven quantum vacuum interactions
  • Forces are theoretical and disputed
  • Needs new physics interpretations
  • Relies on controversial quantum vacuum plasma concept
  • Incomplete theoretical framework
  • Limited experimental validation

Bottom Line

The fundamental difference is that CID operates entirely within known physics using measurable forces, while the Q Thruster requires theoretical quantum effects that haven't been proven to generate macroscopic forces. CID's thrust mechanism can be fully explained using classical electromagnetics and mechanics, whereas the Q Thruster relies on speculative quantum vacuum effects that would require new physics to explain the claimed thrust generation.

0 Comments
2024/12/02
10:12 UTC

5

CID™'s Vertical Setup Eliminates Gyroscopic Precession.

1 Comment
2024/12/02
05:05 UTC

3

 Propellantless Propulsion: The Complete Picture Current Systems Analysis:

 EmDrive:

  • Uses microwaves in a closed cavity
  • No definitive mathematical proof
  • NASA tests inconclusive
  • Theory conflicts with physics laws

 Mach Effect Drive (MED):

  • Claims to use Casimir effect
  • No comprehensive mathematical validation
  • Experimental results disputed
  • Lacks peer review

 Exodus Tech System:

  • Claims 1g of thrust
  • No published mathematical framework
  • Pending patent verification
  • No peer-reviewed results
  • Theory needs validation

 CID™:

  • Measurable thrust: 0.313 N
  • System efficiency: 0.58%
  • Complete mathematical framework: F_net = -∇(m·B) + mω²r B(r,t) = B₀(R/r)³[2cos(ωt)r̂ + sin(ωt)θ̂]
  • Conservation law compliant
  • Reproducible results

 Key Differences: Only CID™ provides:

  • Published mathematical framework
  • Verified thrust measurements
  • Conservation law compliance
  • Reproducible experimental data
  • Peer review ready results

 Future Development:

  • Scaling up CID™
  • Improving efficiency
  • Publishing peer-reviewed papers
  • Industrial applications
1 Comment
2024/12/01
06:00 UTC

9

The first propellantless propulsion with math to prove it. 🚀 CID™ (Centrifugal Impulse Drive) 🧲 F_net = -∇(m·B) + mω²r | B(r,t) = B₀(R/r)³[2cos(ωt)r̂ + sin(ωt)θ̂] | F_c = mω²r | η = (F_net·v)/P Video is sped-up 7 x's to show movement. www.qde-inc.com Does not violate any laws.

31 Comments
2024/12/01
00:14 UTC

6

Exodus propulsion technologies has a new video

Arround 27 minute, he said it will be a video of plate levitating "in a couple of months".

1 Comment
2024/07/07
21:56 UTC

2

Dmitry from r/Osenilo still pretty much believe in EmDrive. Recently, under a major publisher, he released his book on the ether

0 Comments
2024/07/03
02:42 UTC

6

Where exactly was EmDrive tested?

Did I get that right how early test of the EmDrive was carried out on the ground level but the latest test rendering him unusable were carried out in space or in some other significant altitude?

6 Comments
2024/06/21
05:23 UTC

32 Comments
2024/04/30
17:15 UTC

2

Continuation of the research from the physics paper looking into high voltage asymmetrical capacitors

0 Comments
2024/04/30
01:58 UTC

5

Hypothesis on the nature of the thrust in Exodus’s design, and ideas for possible avenues for improvement:

2 Comments
2024/04/22
18:16 UTC

1

Update PNN

The colonization of the Moon and Mars remains a dream if we rely on rocketry

https://www.propulsion-revolution.com/

2 Comments
2024/04/19
20:33 UTC

1

A new electrical generator based on Cathode ray tubes

A cathode ray tube can shoot electrons from cathode to negative electrode, which is similar to the process in an electrical generator. If we have two cathode ray tubes, the tube A shoot electrons to tube B and the tube B shoot electrons back to tube A. Then the electrons have a closed circuit. If the electrons don't hit the anodes, the input power is zero. The kinetic energy of electrons can be converted to output power.

10 Comments
2024/04/16
14:03 UTC

12

The Controversial Quantum Drive was put to Test. It Didn't go as Planned.

19 Comments
2024/02/29
17:59 UTC

14

1701A design, build and test vlogs just released

For the first time after 7-8 years, I have released all my design, build and test vlogs to the public via a sorted Playlist here:

https://youtube.com/playlist?list=PLXewH43ZGxxnpryaAXN-D1pRS27qNFQeq&si=biWtNlsbhd90paeI

I built a modest, crude but effective test lab and did detect about 18mN thrust with 1kW power on a horizontal beam deflector. False positives were certainly possible but I took my project as far as I could since vacuum chambers and magnetic shielding were far above my pay grade.

There are 39 videos in the play list, increasing chronologically. Binge watching might be a way to get through it all. :)

Regardless, I hope it inspires someone to build something new and exciting despite naysayers...

0 Comments
2024/02/10
01:39 UTC

15

Ivo Ltd: "Sadly, Barry-1 had ongoing power-system issues on the bus through LEOP, and after two months of operations, towards the end of LEOP, @RogueSpaceCorp lost communication with the satellite. @ivo_ltd never had the opportunity to test the #QI Quantum Drive."

6 Comments
2024/02/09
14:43 UTC

1

Such Different Ethers

0 Comments
2024/02/08
13:32 UTC

0

EMDR

Does anybody have any idea what happens when EMDR is done but the present is not safe or stable? My therapist has started it with me but my home life is very y bad right now. I had a psychotic break around seven years ago and I’m pretty desperate as nothing is working. I had a lot of childhood trauma but had been extremely high functioning until age 44 when I submitted my PhD and descended into delusions. I have the original trauma and now terribek trauma from the psychosis and fall out from that.

6 Comments
2024/02/06
19:02 UTC

5

Have Their Been Any Updates On Barry-1?

I know patience is needed for real science to happen. I'm wondering if they have turned on the experimental thrusters yet. I don't expect to know if it works yet.

4 Comments
2024/02/05
02:57 UTC

8

Bad data for Barry-1

I decided to compare the reported speed of Barry-1 against the calculated orbital velocity of Barry-1 and found a problem. My graphs are only as good as my data, and my data could be bad.

When using this source for velocity and altitude, a comparison of the reported orbital velocity and the calculated orbital velocity are inconsistent, with a 1.6 km/s difference in velocity at the current altitude. A comparison of the calculated orbital speed from mean altitude using a different source disagreed with both the original source's reported orbital speed and the calculated orbital speed from altitude.

The red dots are the reported orbital velocity. The blue dots are orbital velocity calculated from altitude. Both red and blue use data from the same source. Black dot is calculated orbital velocity from altitude using the mean orbital altitude from a difference source.

  • Inorder for the reported velocity to be valid, the satelite must be orbiting at 530.5 km.
  • Inorder for the calculated velocity in blue to be valid, the satelite must be orbiting at 503 km altitude.

I think we need to look for better sources of data if we are going to track Barry-1's progress.

3 Comments
2024/02/01
13:40 UTC

14

Last 90 days of BARRY-1 altitude and velocity (corrected)

Screwed up the last one. Lesson learned. Don't do maths when you haven't slept in the past two days; you might post your work.

But I went back to it and redid the graphs.

They show the last 90 days of velocity and altitude data. I think it is interesting the data shows Barry-1 stopped accelerating and the altitude is holding.

I used a rolling average because the data I have is truncate or rounded. I also use the standard deviation to show changes in the rate of change, and their scale. E.g., if the rate of acceleration changes, you will see that in the error bars, which show the standard deviation of the rolling average.

This is the source of my data.

Altitude changes for the past 90 days. Note the day 66 Std D error bars.

Velocity changes for the past 90 days.

The graphs and calculations were done in Mathematica.

12 Comments
2024/01/30
23:25 UTC

11

Direct link to BARRY-1 graph

It's actually quite difficult to find a useful graph showing current orbital data for BARRY-1, carrying the experimental QI drives. This is the best I've found so far. As I understand it, we want to be paying particular attention to SMA, which is the size of the orbit. If the drives work, we should see that value start to level out.
https://celestrak.org/NORAD/elements/graph-orbit-data.php?CATNR=58338

2 Comments
2024/01/29
22:58 UTC

20

BARRY-1 Altitude Trending update (2023-11-28 to 2024-01-28)

14 Comments
2024/01/29
15:18 UTC

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