Cap'n Refsmmat

There's no whistle; it's a Turkish-style kettle: So you could easily pop the lid off the top and pour. Perhaps she needs to try that.

We have a water softener at home, and she might actually use distilled water for her tea; I can't remember. The water softener would add some sodium to the water, which would be left behind when the water boils away. I quoted the email verbatim. The subject line was "Dear Mr. Science Forum Moderator", which meant posting it on SFN was inevitable. Now I have to think up a title for you lot when I send my reply. Ah, yes, this makes sense. The steam in the kettle is hot and low-density; once you start pouring and it begins to cool, its pressure will drop, making it difficult for water to escape. You'd have to remove the lid from the kettle to allow the pressure to equalize.

Interesting. I'm not sure how steam would block the spout, though. Perhaps there's some complicated effect from deposited minerals. It'd be nice if I were home and could inspect the thing.

I recently received a question by e-mail from my mom: The only references online to stainless steel turning yellow mention passivation, which I don't know much about but which doesn't sound like something you can do by leaving the kettle on too long. Any ideas?

A head is about 5 kg, so by F = ma, the acceleration caused by 27 kN is about 5400 m/s2, or 551 g. This would not be very good for your head.

The uncertainty principle does not arise because of poor technology. It arises because of the fundamental nature of reality. Even the best possible measuring equipment would be constrained by the uncertainty principle.

The JASON defense advisory group was commissioned by the Pentagon and its final report was classified. I don't think access to information was their problem. But I can ask Dr. Schwitters, the head of JASON; he's probably going to be my thesis adviser this fall. At movie theaters or malls or kindergartens you have little to no opportunity to create a bottleneck, unless you can deduce intent from "Two tickets for Gigli, please". (Although people buying tickets for Gigli should be treated suspiciously anyway.) No, not if it's security at the cost of a great deal of time and money. Not if we end up interrogating nervous fetishists who just want to feel up some panties at Victoria's Secret as well as guys with guns. Certainly we can stand to inconvenience some fetishists for security, but the security payoff is so low and the inconvenience potential so high that I don't see the point here.

Citation needed. http://www.nature.com/news/2010/100526/full/465412a.html http://www.gao.gov/new.items/d10763.pdf The Israeli airport method has a better chance of success because it involves direct interviews by security officers, rather than passive observation of behavior. Passive observation has not been demonstrated to have any effectiveness whatsoever. Even if the guard's passive observation technique causes him to falsely believe someone is suspicious just 0.0000008% of the time, he will pull aside more innocent people than crazy gunmen. Not even a full-body scanner has that sort of incredibly good false-positive rate. Aurora police had actually recently trained with the Department of Homeland Security for similar attacks: http://www.wired.com/dangerroom/2012/07/aurora-mumbai/

You omitted the biggest drawback: it's just not sufficiently effective. Our population is so large and the number of crazy men with guns so small that the vast majority of any security guard's training would go towards annoying innocent people. For example: there will be an estimated 1.3 billion movie tickets sold in 2012 (source). Suppose for the sake of argument that ten mad gunmen burst into theaters this year. Now, suppose a well-trained guard can prevent or respond effectively to 90% of attacks, either by directly noticing suspicious behavior or by locking doors, establishing security procedures, and watching surveillance cameras. So we're down to one mad gunman successful. On the other hand, the guard wastes one minute of time for innocent movie-goers, because he deems them suspicious and must search their bags, or because a theater must be evacuated due to an unattended bag, or because crowds wait longer in lines due to security procedures. That is 1.3 billion wasted minutes. Now, a quick math based on the federal government's estimated value of a human life (three million dollars as of 2004 - source) shows that, at perhaps fifteen people per massacre, the guard has averted the deaths of 405 million dollars worth of people. On the other hand, if we value those wasted minutes at the federal government's estimated cost of wasted time ($28.60/hr - same source), we find that the guards have wasted 619 million dollars of time. That doesn't include the cost of training or employing the security guards, either, and I'm estimating ten massacres per year, not one. In most years there'd be no saved lives at all. Treating humans as three million dollars of assets may seem callous, but it's essentially the only way to sensibly determine the economic impact of a policy. If we want to save lives in a cost-effective way, we should focus on major killers like road accents, ordinary gun crime, and obesity, not random crazy people with guns. Perhaps we should train our security guards to shout at people and tell them to walk faster. It'd burn some calories.

I have no idea what kind of helmet he wore, but the US military wear helmets capable of taking a .44 Magnum; they're class IIIA on this chart: http://en.wikipedia.org/wiki/Ballistic_vest#Performance_standards It would not, however, feel very good. Also, the goggles and gas mask would not take the shot, and most bulletproof vests would struggle with a .44. You're going to have a hard time carrying a .44 Magnum as your concealed carry weapon, though. If someone in the theater had a 9mm or .45 handgun, they could have opened fire, but they probably wouldn't be able to disable Holmes before getting shot themselves.

Holmes didn't enter the building with his armor and guns. He left the movie 20 minutes in, propped the emergency exit door open, and retrieved his weapons and vest from his car. Most emergency exit doors have the good sense to set off alarms when you open them, but I guess this theater didn't mind people letting in their friends through the back door for some free movies. This is the trouble with merely increasing security presence: we will never run out of places with large concentrations of targets, and we will never run out of easy ways of entering and exiting those places without being noticed. Add security to movie theaters and the next Holmes will target a mall. Add security to malls and the next Holmes will target a kindergarten or an opera or the local supermarket.

Not really. An assault rifle or hunting rifle would penetrate a bulletproof vest or helmet easily. A military vest would include trauma plates over important organs to stop rifle fire, but he would not be impenetrable. It may be difficult to carry a concealed hunting rifle to the movies, though.

It's rather inconvenient to keep a fire hydrant under the pillow. Or so I'm told.

I take it you're not a Glock fan. Ah, I'd not heard the term before; I assumed positive safety referred to a manual safety. (I've heard of drop safeties and firing pin safeties, but not positive safeties.)

Most modern handguns have a bar which sits in the way of the firing pin until the trigger is already half-pulled. We actually have a late-1800s cheapo revolver which advertises this as its "Safety Hammer" feature. Not that I'd advise dropping your weapons on their hammers to see what happens.

I dunno. I feel that 5AM when the cockroach falls off the wall and lands on your knee and wakes you up in the middle of a dream about brain parasites from Mars is possibly not the best time to have a loaded weapon under your pillow.

I think you've missed the meaning of his post. If you own a gun, you are very unlikely to ever experience a home invasion, and even less likely to have to shoot an invader. You are substantially more likely to experience domestic violence using that gun. It's not a question of bad aim during the home invasion; it's a question of whether the home invasion would ever happen. There exist quick-opening nightstand safes and such just for this purpose. There are even gun safes designed to be easily opened in seconds in the dark.

Cut out the attitude, please. I've found your posts very difficult to understand as well. See SFN rule 1. Please also refer to the Speculations forum rules, which require that hypotheses be testable or backed up by evidence. If you don't have any evidence, our work here is done.

No. Everything, heavy or not, is weightless on the ISS. You have to make creative use of Velcro, handholds, and footholds. There's not really a need to keep your feet on the floor anyway. After some practice maneuvering, astronauts get fairly comfortable moving around without gravity's assistance.

Perhaps I can turn this question on its head. Science may to discoveries that could destroy humanity. On the other hand, we face a number of very serious problems -- climate change, energy production, overpopulation, healthcare -- whose solutions can only come from advanced scientific research. Would you have us abandon one possible route to extinction to favor another?

But the question is about new weapons, not preexisting ones. If some national laboratory were to announce "We've discovered a new principle of physics and intend to spend $10 billion on turning it into a superweapon capable of incinerating half the planet in one shot," don't you think people would object? We have the recent example of flu research, where biologists managed to make a much more contagious version of the avian flu virus. The research was voluntarily suppressed and went through various review committees before it could be released. One would imagine that directly weaponizable research would not see the light of day. You might argue that some insane person or group might try to use science to build a superweapon, but as they are by definition insane, there's not much we can do to stop them.

Individuals may lose their sanity, but I think that large state actors will take the certain knowledge of complete annihilation and realize they had perhaps not press the big red button. I also wonder what would be the societal reaction if some new superweapon came under development. I think the disarmament folks would have a very strong reaction.

The user title system is automatic, based on postcount, and has existed on SFN for ten years. Nobody chose to declare you a meson to punish you. http://www.scienceforums.net/topic/104-user-titles/

Mutually assured destruction.

Indeed. I think there's an even better example from the New Testament: who saw Jesus after he died, and in what order? Write down the order of events as given by each of the four Gospels and see what you get. Alternately: Give a timeline of the places Joseph and Mary lived. Include Bethlehem, Nazareth, etc. Do this for each gospel independently. Now compare.