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Uncertain Propulsion Breakthroughs?

centauri-dreams.org

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Re: Uncertain Propulsion Breakthroughs?

#11

Post by extrapickles »

Analemma_ wrote: post #6
thearn4 wrote: post #4

I know Marc Millis, let me know if anyone has any questions and I can try to get his feedback here.

He did so partially in this article, but I would love to see a detailed explanation of a valid experimental setup to test the EmDrive effect. What would an experiment look like where, if thrust were observed, then we could really start to say there might be something here?

There is a list of improvements in the article under "Latest Paper".

Its mainly the need to carefully characterize and document all the test equipment and EM Drive support equipment to make sure its not caused by the test setup. This would involve testing with a dummy load so things like interactions with chamber wall can be ruled out or if there are, the effect can be mitigated or accounted for.

Basically they proved their test setup produces thrust, but haven't proven the thrust was a direct result of the EM Drive. They need to more rigor to prove its only the EM Drive and not a setup error (eg: something like the FTL neutrinos turning out to be a poorly tightened connector).

Re: Uncertain Propulsion Breakthroughs?

#14

Post by xupybd »

Wow, I've not read something like that in a long time. More news needs to be like this. Examining what we know presenting where we are. Not taking sides and polarizing the discussion.

I do think people miss one small aspect of this story. How long has it been since we've had a device built that we've no understanding of the principles of it's operation? I think that's an amazing fluke and (if the effect is genuine) something worth celebrating (just because it's so rare).

Re: Uncertain Propulsion Breakthroughs?

#15

Post by halomru »

Animats wrote: post #7

It's so near the noise threshold. Most of the energy goes into heating the thing; only a tiny fraction comes out as possible thrust. The heating prevents using enough power to get more possible thrust; the thing would burn out. Very frustrating.

If we had any idea how they work (if they work) we could work on optimised designs that generate more thrust and are thus easier to study. But we're not yet anywhere near the stage and instead have to study a design that if it works, is so inefficient that we can hardly tell whether it does anything. Very frustrating indeed

Re: Uncertain Propulsion Breakthroughs?

#16

Post by jdoliner »

Others wrote: post #5
empath75 wrote: post #3

tl;dr; > First, I cannot stress enough that there is no new EmDrive “effect” yet about which to theorize. The physical evidence on the EmDrive is neither defensible nor does it include enough operating parameters to characterize a new effect. The data is not even reliable enough to deduce the force-per-power relationship, let alone any other important correlations.

I don't think that's a fair summary... The author provides a more nuanced view than just "there is no effect." You're nitpicking from one section about theory, without considering the article as a whole. This is especially egregious considering that the article spends so much time talking about confirmation bias.

It even says explicitly:

> Do you want to know our conclusions without any regard to how we reached those conclusions? ... If you answered “yes” to any of those questions, then you, like me, have natural human cognitive dysfunctions.

Re: Uncertain Propulsion Breakthroughs?

#17

Post by nkoren »

Others wrote: post #5
empath75 wrote: post #3

tl;dr; > First, I cannot stress enough that there is no new EmDrive “effect” yet about which to theorize. The physical evidence on the EmDrive is neither defensible nor does it include enough operating parameters to characterize a new effect. The data is not even reliable enough to deduce the force-per-power relationship, let alone any other important correlations.

I don't think that's a fair summary... The author provides a more nuanced view than just "there is no effect." You're nitpicking from one section about theory, without considering the article as a whole. This is especially egregious considering that the article spends so much time talking about confirmation bias.

This.

> ...take the time to notice both the pros and cons of the article, not just the parts you want to be true. Deciphering reality takes time instead of just listening to reflexive beliefs. It requires that one’s mind be open to the possibility you might be right and equally open to the possibility you might be wrong.

Re: Uncertain Propulsion Breakthroughs?

#18

Post by alasdair_ »

xupybd wrote: post #14

Wow, I've not read something like that in a long time. More news needs to be like this. Examining what we know presenting where we are. Not taking sides and polarizing the discussion. I do think people miss one small aspect of this story. How long has it been since we've had a device built that we've no understanding of the principles of it's operation? I think that's an amazing fluke and (if the effect is genuine) s…

Quite a few medicines (especially antidepressants) state something like "we don't really know why this stuff works, only that it does."

Re: Uncertain Propulsion Breakthroughs?

#19

Post by powera »

IMO the "rational" approach is to treat the claims as a bunch of pointless lies until there's a repeatable demonstration. Remarkable claims demand at least some evidence before wild speculation commences. As it is, Harry Potter is just as credible a theory of reality.

After all, they've made the same claim repeatedly for 15 years after their first experiments were demonstrably not what they claimed.

Re: Uncertain Propulsion Breakthroughs?

#20

Post by Trombone12 »

Others wrote: post #5
empath75 wrote: post #3

tl;dr; > First, I cannot stress enough that there is no new EmDrive “effect” yet about which to theorize. The physical evidence on the EmDrive is neither defensible nor does it include enough operating parameters to characterize a new effect. The data is not even reliable enough to deduce the force-per-power relationship, let alone any other important correlations.

I don't think that's a fair summary... The author provides a more nuanced view than just "there is no effect." You're nitpicking from one section about theory, without considering the article as a whole. This is especially egregious considering that the article spends so much time talking about confirmation bias.

The highest the actual summary reaches is "But also, despite those inadequacies, the possibility of a new force-producing effect cannot be irrefutably ruled out."
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