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Uncertain Propulsion Breakthroughs?

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Re: Uncertain Propulsion Breakthroughs?

#71

Post by pmezard »

alasdair_ wrote: post #18
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."

From Wikipedia Paracetamol article (https://en.wikipedia.org/wiki/Paracetamol#Mechanism_of_actio...):

"To date, the mechanism of action of paracetamol is not completely understood."

and:

"It is the most commonly used medication for pain and fever in both the United States and Europe."

"Not completely understood" is not the same as "we have no idea why it works", but still I find it telling for such a popular product.

Re: Uncertain Propulsion Breakthroughs?

#72

Post by samplonius »

stale2002 wrote: post #34
powera wrote: post #19

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.

This is what they are doing. They are sending something into space to demonstrate the effect. Let the experiments decide what is right or wrong.

So "space" is some magical place where measurement error does not exist?

Low earth orbit isn't perfect either. You still have micro gravity. And the experiment requires a lot of power, and very sensitive instruments to measure the phenomenon. How do you get sensitive instruments which are expected to be operating near their error threshold into orbit without damaging them?

Orbital experiments will have to be smaller, and use less power, so the effects will even be smaller. But the instruments will have to be tough enough to withstand 5G. And the apparatus could still be introducing other errors, like coolant momentum, which also isn't magically eliminated by being in space.

Re: Uncertain Propulsion Breakthroughs?

#73

Post by jlg23 »

alasdair_ wrote: post #18
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."

True. Before a surgery, never ask your anesthesiologist how exactly the anesthetic s/he'll give you works.. You might get an honest "we don't know" as an answer..

Re: Uncertain Propulsion Breakthroughs?

#74

Post by speeder »

nonbel wrote: post #40
xupybd wrote: post #26

Earlier quoted context omitted.

Very true. I'd not considered the medical world.

If people treated medical research with the same skepticism they treat this EM drive... the world would be a much healthier and safer place.

Medical research don't suffer from lack of skeptism, instead it suffers from unscientific thinking, shamanism, cargo cults, and so on...

For example: for 30 years we had research blasting cholesterol and saturated fats as evil, because predecessors had that result, some arguments were completely circular (saturated fats are bad because they raise blood cholesterol, and blood cholesterol is bad because a bad thing raises it... with no research trying to find how much any of the two really affect health).

Another example is thyroid diagnosis, after discovery of TSH test, medics started to use it exclusively, and accuse patients with normal results but with severe and advanced symptoms of having psychological issues, also many thyroid doctors never bother in ever asking for other relevant tests, like t3 and antibodies, and the TSH tests frequently use outright dated target ranges, with medics skeptical of new research because the old way is mostly working in their experience (since by their definition, people with symptoms but normal values aren't sick, thus their treatment is 100% effective, since it helps all sick people, and the "non-sick" are delusional and thus it is failure of other medical fields that they are sick)

Other example is any medic that saw patients improve under certain treatment, and then start to always use that treatment in a cargo cult manner, without paying attention to any research that proves that it is misguided, like all those kids forced to take ADHD medicine in their early life.

Re: Uncertain Propulsion Breakthroughs?

#75

Post by DanielBMarkham »

euyyn wrote: post #47
DanielBMarkham wrote: post #37

Earlier quoted context omitted.

Yes. Even if it's the most likely thing, experimenter error, for a half-dozen teams to all have errors and not spot them? That's quite interesting! It's the same situation we had with the FTL neutrinos a while back.

Except the neutrino paper then was a big lot of physicists asking colleagues to help them review, so as to find where the problem was. What I see here is just hype. The former, as opposed to the latter, is what gives confidence that the people involved are doing their darnest not to fool themselves. That what they're doing is actually science.

I don't know. I see a few universities looking into building their own setup. I see the Chinese filing patents, testing them in orbit. I see a 2017 microsat launch. I see a healthy debate continuing over on the reddit Emdrive board.

That doesn't look like people trying to sell things to me. That looks like a lot of different people from different backgrounds playing around with an experimental setup that does something unexpected.

The only difference I see is that with the FTL neutrinos, folks were saying this breaks a mathematical model that we've proven over and over again. With the emdrive, folks are saying If this works, it's by some model we do not yet understand. It doesn't attempt to disqualify an existing model; it suggests there's some other model applicable that we don't quite understand yet.

For most folks, this is quite more upsetting than the FTL guys. I get that. Still, observe first, theorize second. I'm sure the theory folks will catch up, and it'll probably be some sort of EM leakage we're talking about. But maybe not. Maybe we've accidentally come up with a new kind of photon rocket. That's what makes the story fun.

Re: Uncertain Propulsion Breakthroughs?

#76

Post by davrosthedalek »

intrasight wrote: post #57
xupybd wrote: post #25

Earlier quoted context omitted.

Yeah there is a very good chance that's still the case here. But would be cool if it's not experimental error.

That's my sentiments here also - weird outcome would be cool, but I expect that we'll find experimental error. However, there is also the possibility of something in the middle - meaning no laws of physics are broken but the experimental error is itself an interesting engineering discovery.

There is also the possibility that the experiment itself is correct and the laws of physics are correct, but we applied them wrong, leading to a wrong prediction or experiment analysis. Many many calculations take short-cuts or make approximations. Or we apply a theory wrongly. In all these cases, we learn something new. Hitting the prediction (of the standard model) is boring.

Re: Uncertain Propulsion Breakthroughs?

#77

Post by bicubic »

cjensen wrote: post #44
freehunter wrote: post #36

Earlier quoted context omitted.

You sound very negative towards conducting more experiments on this, when the results have been unexpected every time it's been tested. You're displaying the kind of dogma that science has been fighting against since the dawn of time. Either it's true or it's not, but we can't tell until we test it. And so far, it's only been disproven in theory, not in practice. That's worth more experiments.

Occam's Razor says it is not true. If you read the linked article, it is saying, in the most polite and disinterested way possible, that it is not true although they allow, in the driest of terms, that it could be true. I expect if the same authors analyzed the Loch Ness monster or Big Foot, they would also disinterestedly point out the unlikelihood of either and point out the how awful the proofs put forth are while…

I don't expect the em-drive to work, but the parent post has a point. We've had repeated experiments yielding unexpected results. It's worth an inquiry; if nothing else, to thoroughly explain what went wrong so the same mistake is avoided in future experiments.

Outright dismissing new ideas, no matter how far-fetched, is very much the antithesis of the scientific principle. You mustn't forget that everything we take as indisputable fact today, was an outrageous far-fetched theory at some stage.

It was barely yesterday that Barry Marshall was ridiculed for proposing that stomach ulcers are bacterial, because everyone 'knew' that bacteria can't survive in such an environment.

Re: Uncertain Propulsion Breakthroughs?

#78

Post by justinjlynn »

gus_massa wrote: post #51
freehunter wrote: post #36

Earlier quoted context omitted.

You sound very negative towards conducting more experiments on this, when the results have been unexpected every time it's been tested. You're displaying the kind of dogma that science has been fighting against since the dawn of time. Either it's true or it's not, but we can't tell until we test it. And so far, it's only been disproven in theory, not in practice. That's worth more experiments.

> You sound very negative towards conducting more experiments on this, when the results have been unexpected every time it's been tested. This is wrong. There is a strong selection bias, where a many team tried this and only those that got a "successful" measurement get press. It's very difficult to get the list of all the unsuccessful (unpublished) experiments, but someone recollected a list em-drive test http://emd…

A relatively strong argument for experiment pre-registration as a prerequisite for eventually publishing.

Re: Uncertain Propulsion Breakthroughs?

#79

Post by madengr »

therein wrote: post #69
madengr wrote: post #66

Earlier quoted context omitted.

There was another paper about 15 years ago where a electrically pulsed, superconducting thin film was able to displace a pith ball from tens of meters, through walls. I can't find the paper but it was on arxiv. Some sort of gravity pulse; weird shit.

Made me think of this. Maybe when they were doing the experiment, a gravitational wave happened and they somehow reflected it? > Thin superconducting films are predicted to be highly reflective mirrors for gravitational waves at microwave frequencies. The quantum mechanical non-localizability of the negatively charged Cooper pairs, which is protected from the localizing effect of decoherence by an energy gap, causes…

They were able to repeat it. Damn, I wish I could find it. I actually have it printed off somewhere.

The issue is that distorting gravity has far more consequential effects due to generally relativity than just moving something. You are actually distorting time too.

Re: Uncertain Propulsion Breakthroughs?

#80

Post by euyyn »

DanielBMarkham wrote: post #75
euyyn wrote: post #47

Earlier quoted context omitted.

Except the neutrino paper then was a big lot of physicists asking colleagues to help them review, so as to find where the problem was. What I see here is just hype. The former, as opposed to the latter, is what gives confidence that the people involved are doing their darnest not to fool themselves. That what they're doing is actually science.

I don't know. I see a few universities looking into building their own setup. I see the Chinese filing patents, testing them in orbit. I see a 2017 microsat launch. I see a healthy debate continuing over on the reddit Emdrive board. That doesn't look like people trying to sell things to me. That looks like a lot of different people from different backgrounds playing around with an experimental setup that does somethi…

> It doesn't attempt to disqualify an existing model

It would very much disqualify conservation of momentum, which is another way of saying that the laws of motion are the same here and one meter down the road.

Conservation of momentum has been observed in countless experiments for centuries, in a broad range of conditions. It was indeed observed first; there's no catching up needed for the theory. It's always valuable, and in a sense exciting too, to test it again beyond the range where it's already been tested, even if you expect a negative result (the null hypothesis holding). But that's not what's happening:

If your goal is to learn, and you see momentum not being conserved in your prototype space engine, you start dismantling it, simplifying it, until you stop seeing it. And then go back one step to see it again. Your device might not be a space engine anymore! But now it's simplified; easier to reproduce, and easier to model and analyze. The laws of nature don't care about the purpose and coolness of your device, they apply the same. You also take your measurement apparatus and calibrate it against something unrelated, in many conditions, to make sure it's not lying.

You might have a different goal than learning: to achieve cheap space travel, which is a great thing. If then you build a prototype space engine with the hope that it won't conserve momentum, and you see a positive result, there's already the first red flag. If when you see that, what you do is trying to explain it with new (or with wrong) theory instead of questioning it, there's the second red flag. Healthy debates, and playing with technology in a lab, are good things. But not all good things are science. Our minds are too easy to fool, and people are doing this without condoms.

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