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Gravitational Repulsion Effect Claimed
TekPolitik writes: "Eugene Podkletnov, the physicist who claimed to have discovered an anomalous gravitational "shielding" effect in the 90s, but withdrew his original paper prior to publication, has finally published a new paper on the topic. The paper describes a new experiment that is related to the original experiment, but the nature of the new experiment is more suggestive of an inverse gravitational effect (that is, the device creates a gravitational push away from it), or in Trekkie terms, a repulsor beam. Aside from claiming to have pushed things around at a distance, Podkletnov claims that the results directly contradict general relativity." Let's see if I can summarize: the author claims that with a certain very cold superconductor transmitting a large quantity of electricity in an intense magnetic field, he has observed a "new" force which repulses objects.
Another glib, uninformed remark rated as Insightful -- two people who obviously didn't bother to read the article. Well that's the Internet for you.
To sum it up: They built this magic superconductor thingy in a vacuum chamber, charged it up and measured the effect at different distances on pendulums of various materials, weighing 10 to 50 grams, hung in a separate vacuum chamber see their rough drawing. When they fired up the superconductor, the pendulums swung away several inches.
The amount of movement varied with the mass of the pendulums, but not the distance or the materials (they mention metal, glass, ceramics, wood, rubber, plastic). Pendulums 6 meters and 150 meters away in a different building, separated by brick walls and an inch of steel, showed identical effects. Even with "trace amounts of iron" a magnetic effect would vary with the square of the distance. But what do I know?
Of course, perhaps I'm prejudiced against people who criticize research without bothering to read it (and moderators who hand out points like candy).
> A couple of weeks ago while I was out at a wrecking yard digging up parts for one of my cool old cars, I watched an electromagnet lifting cars. That's a lot of iron filings.
> Similarly, 200 years ago, an ebony rod attracted grains of pepper. Now, we harness electrostatic attraction and replusion for all sorts of things, ranging from TV sets and computer monitors to Van de Graaf generators which power linear accelerators at nuclear research facilities.
Yes, but the important difference between weakness of magnetism 200 years ago, and weakness of gravity right now is the reason why such weakness was observed.
Your ebony rod is so weakly electified because although it comprises an impressive number of charges, most balance out (there are positive and negative charges which cancel each other's effect out). Net electric charge is only caused by an imbalance between positive and negative, and this imbalance is incredibly low: maybe only one electron per atom, and only on the surface. ALthough the mass of the object may be high, only a tiny part of that mass contributes to the effect. And during the last 200 years, we've just been getting better at augmenting the proportion of the mass that has an effect.
Magnetism involves movement of charges. In case of natural magnetism, this is the (non-cancelled) movement of electron around the atom's nucleus. In most materials, this cancels out because:
Today, the strongest magnets are, as you correctly pointed out, electromagnets. In those we have a macroscopic movement of charges (i.e. electric current), which we can theoretically make as high as we wish (as permitted by the electrical resistence of the material and electric power at our disposal...)
Gravity is different though: there are no "negative" gravity particle which could cancel out the normal positive gravity, or at least there are none known today. Weakness of gravity thus does not come from cancellation, but is rather inherent in the force itself! The active principle in gravity is mass, and the only way to get "better" gravity is indeed to augment the mass. Moreover, unlike magnetism, gravity is not tied to movement, thus we cannot manipulate it either by speeding up the objects (at least not until we reach relativistic speeds).
> Consider that, to my knowledge, we've still got no higher understanding of why two positively charged ions repel, or why a positively charged ion attracts a negatively charged ion. Nor do we really understand anything more about magnetism's lines of force than the pretty little lines of iron filings on the paper when we rest it over a bar magnet. Like gravity, they're fundamental forces. We know a little bit about how to use them - the variables involved. Mass, materials which maintain an electrostatic charge well, and ferrous metals. We know they're inter-related. But how do the forces themselves work?
We may not know the philosophical reason why magnetism and electricity exists at all, but we have a pretty detailed understanding however how they interact (Maxwell equations), why the electric/magnetic field is shaped the way it is, how those forces propagate, etc.
> With our present knowledge, we're at about the level of proficiency of a secretary who is good with Excel and yet still refers to her computer as a "hard drive". We can make two of these forces do the things we want them to do, but we don't have any higher knowledge of how they work.
Our knowledge of magnetism/electricity may not be complete enough to satisfy a philosopher, but it is certainly complete enough for an engineer, and well beyond that of your Windows toting secretary knowing nothing else than Excel.
Gravity is the weakest form of energy, it needs an incredible amount of mass to create a noticable amount of effect.
Sure, that's easy to say now, but not 200 years ago. 200 years ago, a lodestone was *the* magnet. It was a piece of rock that attracted iron filings.
A couple of weeks ago while I was out at a wrecking yard digging up parts for one of my cool old cars, I watched an electromagnet lifting cars. That's a lot of iron filings.
Similarly, 200 years ago, an ebony rod attracted grains of pepper. Now, we harness electrostatic attraction and replusion for all sorts of things, ranging from TV sets and computer monitors to Van de Graaf generators which power linear accelerators at nuclear research facilities.
Consider that, to my knowledge, we've still got no higher understanding of why two positively charged ions repel, or why a positively charged ion attracts a negatively charged ion. Nor do we really understand anything more about magnetism's lines of force than the pretty little lines of iron filings on the paper when we rest it over a bar magnet. Like gravity, they're fundamental forces. We know a little bit about how to use them - the variables involved. Mass, materials which maintain an electrostatic charge well, and ferrous metals. We know they're inter-related. But how do the forces themselves work?
With our present knowledge, we're at about the level of proficiency of a secretary who is good with Excel and yet still refers to her computer as a "hard drive". We can make two of these forces do the things we want them to do, but we don't have any higher knowledge of how they work.
Gravity is, of course, the most difficult of the fundamental forces to research, because it would require either huge masses that you can manipulate at will or incredibly accurate measuring instruments. 200 years from now - maybe even sooner, who knows - we'll probably be able to manipulate gravity at will. Maybe not around the Earth, but maybe around a space ship which we wish to launch from the surface.
Certainly, there's a huge motivation to studying it, especially if it can be harnessed as easily as magnetism. How much does a Space Shuttle booster tank cost to fill?
Fire and Meat. Yummy.
Just because a phenomenon is new doesn't mean that nobody except for its discoverer is qualified to look at it. There are plenty of people in the same general area of experimental physics who are fully qualified to judge whether he's adequately controlled for experimental variables, done proper experimental design, fully considered alternative explanations within currently accepted physical law, etc. Most of the time that somebody discovers something new it turns out that the real explanation is a flaw in their experimental controls, data analysis, etc. and not a genuinely novel phenomenon. Getting other people who know what they're doing to doublecheck your results is a good way of catching that kind of error. That's why peer review exists. Somebody who trumpets his discovery before having others double-check his methodology is doing something highly questionable.
There's no point in questioning authority if you aren't going to listen to the answers.