John Cuthber

Fusion works with all the elements up to about iron. That's how they are made. They are made in stars, and the whole lot are gases under those circumstances. It is, in principle, possible to make a fission reactor with uranium hexafluoride vapour. There are plenty of plans for using molten salts for fission reactions of thorium. The physical state is not fundamental to the fission/ fusion process; it's a coincidence.

What? You say "There is nothing impolite, arrogant or demonstrative of a closed mind." in respect of someone saying there's no strong evidence for the big bang? That claim looks arrogant and closed minded to me.

At 100 million degrees there are no solids. Plutonium and uranium have both boiled several orders of magnitude cooler than that. All the materials that might sensibly undergo fusion are plasmas. And it's perfectly possible to do sustained fusion at fairly low pressures (much less than ordinary atmospheric pressure).

Foam, feathers, some such thing. One important criterion is that the density must be low.

I know they are quite bright as birds go, but that's not the point. Can you choose to believe that I am one? Can you choose to believe that I'm a unicorn? Or is what you believe something that you are stuck with because it follows from your experience and the evidence?

"foucault pendulum is about changing the angle of swing, and not about rotating. " Wrong on both counts. Can you answer two simple questions What effect are you talking about? Is there any evidence that it actually exists?

Not exactly, They would do something, but not enough. You would do better using a bigger thickness of something much softer. That way the deceleration would be smaller and the forced would be less.

Really, can you choose what to believe? For example, can you choose to believe that I'm a super-intelligent crow? Do you really think that there's a bird typing this?

It is found in wiki. "to explain why a hanging object by string will spin around its vertical axis when we turn the string around," http://en.wikipedia.org/wiki/Torsion_spring " why any object hanging with a string will rotate due to earth's motion" http://en.wikipedia.org/wiki/Foucault_pendulum

Of course, it depends on the nature of the education. It is possible to avoid teaching people how to think, and it's the deliberate policy of some political groups. http://www.washingtonpost.com/blogs/answer-sheet/post/texas-gop-rejects-critical-thinking-skills-really/2012/07/08/gJQAHNpFXW_blog.html#

Why is that ridiculous? Anyway, if a rigid body falls for a distance x and is brought to a halt over a distance y then the average impact force is x/y times the body's weight. (neglecting air resistance of course). "I've been trying to calculate, as a rough example, how much force a person would experience if they dropped from freefall at terminal velocity and hit the ground with one of these pads on each of their shoes. " Well, I'm not sure how far you have to fall to get to terminal velocity (strictly speaking, you never quite do) but it must be something of the order of hundreds of metres. Call it 1200 metres- just to have a number to work with. If you are then brought to a halt over a distance of 12 mm (the thickness of the pad) your feet would be subject to an acceleration of about 100,000g That's going to be messy. Consider your head. It will be slowed down and stopped over the course of about 1.8 metre (your height). 1200/1.8 = an acceleration of about 700 g A human head weighs about 5Kgf so it would be subject to about 3.3 tonnes force Still messy. Of course, it would also suffer some damage as it ploughed through the rest of your body. It wouldn't matter much since it would trash the lungs heart etc.

It's an easy enough idea to test. There should be a negative correlation between years in education and cognitive ability. Those whose jobs require a lot of problem solving- drs and engineers should have relatively little schooling. Is that what we find?

That should be easy. Show us an example of something that you have discovered using this "other means". If it s any use, you should be able to do that. Of course if you show us something which turns out to be wrong, you will have shown that this "other means" simply doesn't work and you can stop spending more time on it. (It's probably better to start a new thread about that)

You might want to compare the cost of the electrical energy used in pumping down the system to a good vacuum and the cost of the night watchman. I suspect it's not worth worrying very much about the cost of running the pumps. The saving tanks would be roughly as expensive to produce as the main tower. Siting it in an old mine shaft would be a sensible idea- unless there just don't happen to be any mines near the University. It's a lot easier to build a tower than to dig a well. You have pointed out that there are 4 ways to get microgravity. All 4 get used. You say "I find puzzling that people build 150m tall towers to get few seconds of microgravity" I'd be a lot more surprised if we didn't. We do a lot of very much more expensive and difficult things that that for the sake of research. Why not have a drop tower? It's cheap (in comparison to a lot of research equipment..

OK, so I have a choice. I can believe that the carbon atoms in a lump of coal are not essentially joined in hexagonal rings and stacked in layers- even though things like the XRD patterns show that they are- and that those peer reviewed papers about burning graphite are wrong. Or not. Not the most difficult decision I have ever made. I guess other reading this will come to their own conclusion.

To get back to the topic... Nobody actually knows the answer. Plenty of people will say they do. That blind belief, in the absence of sound evidence, is more akin to religion or politics, than to science.

http://xkcd.com/285/

"We should engineer one of our organs to continually regenerate" No problem: it's called cancer. "that way we could give pieces of it away to those in need." We do, for example, http://en.wikipedia.org/wiki/HeLa

That rather depends on circumstances. For example, I might be able to cite evidence that economic models are often based on the assumptions of rationality with perfect knowledge http://en.wikipedia.org/wiki/Economic_model#Pitfalls and that people are not, in fact, rational. see, among other works, Irrationality: The enemy within, a lay reader's guide to the psychology of cognitive biases and common failures of human judgement. by Stuart Sutherland. In that case, it's not my incredulity that matters, it's the evidence. And the evidence shows that, at best, rather a lot of economics is unscientific.

Most economic "theories" I have come across assume rational people and perfect knowledge.That's simply not a scientific model.

"I think Economics is a science." Well, it isn't my field, but I don't. Perhaps you could explain the mathematical laws that allow economists to make predictions an give some examples of how that predictive ability has been used to avoid stock market crashes and slumps in the economy. Or, if you prefer, as Truman said "Give me a one-handed economist! All my economics say, ''On the one hand? on the other.'' or http://cheezburger.com/2814131200 To be fair, you have posed an interesting and important question. I doubt that anyone could actually answer it . I also doubt that there would be any difficulty finding economists who would say "yes", and other economists who would say "no" and both groups would be sure they were right. If you ask two scientists what colour hydrated copper (II) sulphate is they will both tell you it's blue. Why do we not find that level of agreement among economists, if economics is also a science?

It may have escaped our notice, but changes are happening faster than they ever did before. That would explain why there has never been a revolution anywhere, at any time.

And yet, we change. Or have you not noticed that we are no longer in the stone age? Actually it goes further than that; you say "We cannot train to adapt to a new idea precisely because it is new and we have thus nothing to guide us." Well, were you born with all the ideas and views you currently hold, or have you adapted to them? We all started with little or nothing to guide us- yet we learned a lot.

What does the "censorship" stop me saying?