They have presented evidence and a proposed mechanism, have fully published the details of their work, and have invited others to attempt to replicate it or to show where they're wrong. Where's the "pseudo"? It's also important to note that in experimental physics it's more than enough to show an effect that can be replicated. Their currently proposed theoretical explanation could be wrong, but that wouldn't matter.
The article also sets off various other pseudoscience alarm bells, such as the fact that their paper is published in a philosophy journal, and the guy having a history degree instead of a physics degree. But that goes against the naive rebellious spirit of HN that dictates that anybody can overthrow fundamental physics with an experimental setup in his basement, so downvote away!
The article is very much written in the second form, at least as far as I can tell.
"ninety-nine percent convinced" That's not "hmm, that's funny, let's investigate more".
"The theory has been sitting in peer-reviewed literature for more than fifteen years" (a single paper in a philosophy journal...)
"Those who are players in the field of advanced propulsion," he says, "feel obligated, for whatever reason, to dissuade people from considering seriously alternatives to their particular scheme. I think they may genuinely feel they are doing a public service when they say, 'Don't spend money on that, it can't possibly work.'" He gives me a wry smile. "But their own schemes have all failed." Implying that the space industry should invest in it.
She became "ninety-nine percent convinced." She started out skeptical until she investigated it thoroughly.
"Sitting in peer-reviewed literature" only applies to "something obviously wrong with it." He's saying that, if there's a flaw, it must be subtle. That's not saying "therefore it must be right" but merely that there are no obvious flaws.
And for space industry investment, I really don't see the problem here regardless of the context. Imagine, for a moment, that this was a completely legitimate thing that failed to attract any investment. Why would he not say those exact words? If this is something that could be said both by a kook and a legitimate scientist working on a legitimate theory, does that not mean the statement has no deciding power?
It looks to me like this fellow has quite a few peer-reviewed papers out there. Most are indeed in that weird journal, but not quite all.
And I just flat-out disagree with your supposed implication about investing.
Let me be clear: I doubt this effect is real. The difficulty of reproducing the experiment and the fact that the observed effect got smaller as they refined their technique both imply that there's some confounding factor at work. But I don't see any "pseudoscience" here.
"such as the fact that their paper is published in a philosophy journal, and the guy having a history degree instead of a physics degree." -- argument from authority, very unscientific. If an unemployed poodle shaver publishes a replicable experiment, it is science.
"naive rebellious spirit of HN that dictates that anybody can overthrow fundamental physics with an experimental setup in his basement" -- if the experiment works and can be replicated, they certainly can.
There's also a misunderstanding of scientific epistemology in your last statement. Theories are seldom overthrown, but they are often extended. Einstein didn't overthrow Newton -- he provided an extension. Newton's equations still work, but with a very tiny error that only becomes visible at high velocities or with unbelievably precise measurements unavailable in Newton's day. A theory is not an absolute dogma, but a model that is deemed correct within its context -- namely all data and experiments available at a given time. New data or new experiments can extend the context, requiring an extension of theory. If this effect is real, it would not "demolish" or "overthrow" relativity, but would likely require some sort of extension to the theoretical framework. Who knows? Perhaps such a thing could point in the direction of the elusive quantum / relativity synthesis?
I am skeptical (lower-case S) of this, in that I wouldn't really believe it unless the effect could be reliably amplified. So far that hasn't been the case. But I don't consider it at all psuedoscientific to try it out. Even if the effect is a result of something else, doing so will refine your skill at measuring tiny forces and possibly advance the field of experimental technique.
The character assassination and arguments from authority are completely unwarranted, and is a major reason I am not a Skeptic (upper-case S).
P.S. a tangent:
Part of why I think CS advances so fast is that the unambiguous nature of computer "experiments" leaves little room for arguments from authority or character either pro or con. Either something works or it does not. Politics -- that age-old enemy of truth -- are clearly irrelevant.
Except for the fact that he says: "The theory has been sitting in peer-reviewed literature for more than fifteen years, so if there was something obviously wrong with it, the odds are, more than one person would have said that it's not right.". I'm just counting that claim.
> if the experiment works and can be replicated, they certainly can.
And guess what, it wasn't replicated!
> There's also a misunderstanding of scientific epistemology in your last statement.
I understand that, but conservation of momentum is one of the most fundamental facts of physics, maybe even THE most fundamental fact of physics, certainly as fundamental as conservation of energy (in relativity it's basically the same thing -- both are components of the energy-momentum 4 vector). It holds in Newtonian mechanics, general relativity, and in quantum mechanics. It is at the very basis of those theories. Finding something that contradicts that would completely destroy that foundation. It would be the single biggest discovery in the history of science. To present that with such confidence as the article does is just ludicrous. If the article was about creating energy from nothing, should that be taken seriously too, with similarly weak evidence?
Yeah, it'd be pretty huge, but it wouldn't "overturn" anything. All the science we've done to date remains quite valid.
Our current theories all state that momentum is conserved. That's because all our current experimental data shows that momentum is conserved.
Now let's say we had a new experiment that showed what appeared to be a violation of conservation of momentum?
This would mean we'd need a new theory explaining how this experiment worked. But this new theory would also have to explain all our previous experimental results -- in precisely the same way that Einsteinian mechanics encompasses, explains, and agrees with all of Newton's results. In other words you'd have to answer the question of "if momentum isn't always conserved, why does it almost always look like it's conserved?"
There's another possibility too. What if this thing works and momentum is still being conserved? What if it's pushing against something, such as some kind of dark matter field, WIMPs (weakly interacting massive particles), neutrinos, virtual particles, ...??? I'd start by asking questions like that before I'd toss conservation of momentum. Even the hardest vacuum is full of particles ejected from stars and other things flying all over the place and even "popping into and out of existence" (in quotes because that's only an analogy) as shown by things like the Casimir effect. What if it's a "WIMP thruster" or something weird like that? An interesting experiment would be to send one flying on a one way trip to nowhere out of the solar system and see if it works as well in interstellar space as near the sun. The sun's throwing out a lot of particles, could it be pushing against those? Has he ever tried running it at night (far side of Earth) vs. during the day (sunward side of Earth)?
Of course it'd still be really useful as a space drive if it could be scaled up, regardless of the mechanism.
I'd build two and have them push against or toward each other. Must be something funky in there.
I wonder if the thing, or a part of the thing, changes thermal energy more/faster than it changes kinetic energy? That would be an interesting conservation solution. If it would be energetically cheaper to just heat something up that has differential IR emission on each side...
That's what they are claiming: gravitational waves travel back in time, and move all the other matter in the universe a little bit so that momentum is conserved. Or something.
My reading is that this thing, assuming it worked, would have the same problem as ion drives in that it would require a massive power plant. It solves about 1/3 the technical problem of a star drive: where to get the mass. But about 2/3 of the problem of star travel is where to get the energy. High-power-density fusion and antimatter-matter annihilation are the only sources I know of that make star travel thinkable on anything like a human time scale.
Which, funnily, leads back to a point others and I were making in a different subthread[0] - that any device that allows interplanetary travel in timespans reasonable for humans is at the same time a weapon of mass destruction.
Humanity needs to get its act together if we're ever to get out of this rock :).
We already have plenty of weapons of mass destruction -- sufficient to eradicate modern civilization if not human life entirely -- so its hardly as if not developing technologies necessary for interplanetary travel protects us from such weapons.
That's a good indication that the effect isn't real. But it has nothing to do with whether this thing is "pseudoscience." Proper science produces negative results all the time.
"-- argument from authority, very unscientific. If an unemployed poodle shaver publishes a replicable experiment, it is science."
Not only is it an unscientific argument, it's just wrong. The guy did his undergraduate and masters in physics, then switched to history of science for his doctorate because he realized that nobody was going to fund what he wanted to work on and he needed a job. He also works with other physicists who do have doctorates in physics.
That's very logical -- it's incredibly hard to fund anything speculative.
My underlying point is that being honestly wrong doesn't make you a pseudoscientist, and should not result in character assassination or claims of being a fraud or a quack. That sort of thing contributes to a climate of dogmatism and extreme risk aversion in science that more or less guarantees that nothing new will ever be discovered.
The data can't 'go against' general relativity because it's agreed by everyone--the researcher included--that he hasn't got all the variables controlled, and so the data doesn't 'go' at all.
It'd be pseudoscience if he was cherry-picking data that shows his theory to be correct, or ignoring existing data that conclusively shows that his theory is incorrect. He doesn't seem to be doing the former; I don't really have a way of telling if he's doing the latter.