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Comment Re:this attitude is part of the problem (Score 1) 189 189

The attitude that we don't discuss possible downsides is a result of the problem, not the cause. The problem is that a lot of people are irrationally anti-vaccine, will grab onto any lame evidence that their pre-existing opinions are correct, have some influence on policies, don't vaccinate their children, and spread more irrational anti-vaccine propaganda.

We saw this in the AGW "debate", in which the apparent slowing of atmospheric warming was jumped on by AGW denialists.

Comment Re:Not the best summary... (Score 1) 189 189

You seem to think that there's a single "stronger" vs. "weaker" spectrum, that there's some inherent virtue to evolution, that eliminating one source of selection pressure can stop it, and that significant evolution can take place in a generation or two. None of these are true..

Comment Re:Not the best summary... (Score 1) 189 189

The government's been forcing you to pay for other people's medical care for a long time, I think since Reagan was President. If a desperately sick person goes to an emergency room, that person has to be treated and stabilized. This is about the least efficient health care system imaginable, and getting people to see regular doctors before they're that sick is going to save money.

Comment Re: Looking more and more likely all the time... (Score 1) 436 436

According to the laws of physics as observed for centuries, momentum is conserved. We know that not having conservation of momentum leads to the laws of physics varying significantly over a fairly short distance, which we have never observed before. The skepticism is that it produces any thrust at all, since there is no reaction mass. If you'll point me to at least a few peer-reviewed papers validating the result, I'll start being skeptical about the thrust.

Comment Re: Looking more and more likely all the time... (Score 1) 436 436

I have no idea what you mean by a "forward theory", but the rest of your post is nonsense.

Some guy thought "it should work like that", and was wrong. The original theory presented has been torn to pieces, and the guy's got a new theory that hasn't been torn to pieces yet. It's not going to be valid, because it doesn't explain how the laws of physics vary over a short distance in a way that's never been observed before.

It doesn't work according to classical physics, or any other physics we know. If momentum is not conserved, then physics needs a complete rebuild. If it's throwing something else out the back, somebody needs to figure out exactly what this matter is that has never been observed before but is manipulable by microwaves in an asymmetric cavity.

Comment Re:Blimey (Score 1) 436 436

You say that the apparent violation of conservation of momentum is a failure to recognize the true size of the system involved. Then you give two examples of conserving energy, a considerably different thing. What is the size of the system involved that conserves momentum?

Comment Re:The Dean Drive is back (Score 1) 436 436

The different between this and the Dean drive is that this drive is described in enough detail that it can be replicated and tested by others. If an independent scientist had a Dean Drive, about the first thing said scientist would do is put it on a pendulum, refuting the claims. In this case, we have at least some independent scientists testing it, which means it's not easily shown to be bunkum.

Comment Re:ah, Tajmar eh? (Score 1) 436 436

If a ballerina trips over scenery, tries to recover, and falls on her ass, I'm pretty safe in considering that a mistake, despite the fact that I know very, very little about ballet. If I happen to know that conservation of momentum is a fundamental part of physics, and that's something very basic, then if something appears to violate it I'm justified in calling for absolutely unimpeachable evidence.

Comment Re:Physics time! You misunderstand ion drives (Score 1) 436 436

Think of it this way: suppose we can get a fixed amount of momentum from an energy input. Momentum is mv and kinetic energy is mv^2/2, so kinetic energy increases faster with velocity and hence momentum the faster the thing is moving (the bigger v is).

Let's assume that for 1000 units of energy we can get 1 of momentum. Accelerating from v=0 to v=1 increases the kinetic energy by 1/2 unit, so it's way unprofitable. Now, let's suppose v=1000. By using 1000 units of energy, we increase kinetic energy from m(1000)^2/2 to m(1001)^2/2. The square of 1001 is 2001 greater than the square of 1000, so we get our kinetic energy increased by 1000.5, which is very slightly more than the energy we put in. If the velocity is 2000, then we get kinetic energy increased by 2000.5 for 1000 input. No matter what the ratio of energy to momentum, we can go fast enough to get free energy out of it.

Comment Re:Why the controversy? (Score 1) 436 436

This drive purports to convert energy to significant force (far more than you can get by firing off the energy directly) without reaction mass. The difference between space and Earth, in your example, is that the Earth has reaction mass. An aircraft uses the atmosphere as reaction mass. A ship uses the water it's in, and so on. In space, you need to bring your own.

So far, the drive is not very efficient (assuming it works at all). I don't trust theoretical projections, because I don't believe it can work with physics as we know it. It may never be useful where there's noticeable amounts of friction. However, we already have useful means of converting energy to motion in air and water and on land, so we don't need it there.

Nuclear reactors are currently an expensive way of powering a ship, compared to burning something. They're extensively used in subs, since they don't consume oxygen and can be used indefinitely at any depth, and the USN uses them in carriers. I'm not completely sure why, but it may have something to do with a lack of exhaust gases that have to be expelled and which can mess up flying conditions.

Comment Re:Believe it when I see it (Score 1) 436 436

They aren't entirely different. In evaluating scientific discoveries, you have to keep in mind that an individual scientist might be delusional, sloppy, or a liar. Most scientists are honest, sane, and painstaking, but not all. In the case of a potential breakthrough like this, you have to keep in mind that there are a lot more liars than revolutions in science.

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