Might as Well Jump

Following the drops dancing on a water surface, I was sent a link to drops jumping around on a super-hydrophobic surface:

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A sphere is the minimum energy configuration, and this energy scales with surface/volume ratio; small spheres combining will represent a change in energy, and this energy shows up as a vibrational mode of the droplet, so it can launch itself off of the hydrophobic material. Bigger drops don’t display the behavior because the energy released is smaller in proportion to the mass that’s present.

Like so many things in science, it is probably obvious in hindsight that it has to be this way, but the real trick is thinking of looking for it ahead of time.

In an earlier post we saw other drop dynamics in microgravity that shows the vibrations when drops combine.

h/t to Tea With Buzz

I Have the Right to Remain Silent

Sheriff Threatens to Submit Photographer to FBI’s Hit List

As someone who likes to take photographs, this kind of scenario scares the crap out of me: cops who overstep their bounds. I’ve never been hassled, but then I take a lot of nature photos, so I’m not exactly a prime candidate for that while I’m out in the middle of nowhere. What’s perhaps scarier than the treatment of the photographer are some of the comments — people who think that it’s perfectly legal for the police to detain you for any (or no) reason whatsoever, and up to 72 hours, or that not answering questions is probable cause that you’ve broken the law. Some people may think the person on the video is being rude. I disagree; I think he was merely prepared. Rights do not evaporate based on your tone, anyway.

I am not a lawyer. But … In general, photography in public places is legal in the US. If cops stop you — for any reason, not just photography — your wisest course of action is probably to say nothing at all. Or just walk away — if there’s no probably cause to stop you, you can’t be detained. The police are allowed to ask questions if they are suspicious and investigating that suspicion, but you are not compelled to answer. (Florida v. Royer, citations and notes omitted)

The person approached, however, need not answer any question put to him; indeed, he may decline to listen to the questions at all and may go on his way. He may not be detained even momentarily without reasonable, objective grounds for doing so; and his refusal to listen or answer does not, without more, furnish those grounds.

In fact, without probable cause, they can’t even demand to see ID (Brown v Texas)

[E]ven assuming that purpose is served to some degree by stopping and demanding identification from an individual without any specific basis for believing he is involved in criminal activity, the guarantees of the Fourth Amendment do not allow it.

(United States v Mendenhall further defines what constitutes seizure/being detained.)

One should also note that the police do have the authority (and rightly so, IMO) to make sure they are not in danger, and can frisk you for, but only to determine whether or not you are armed (Terry v Ohio)

[T]he police should be allowed to “stop” a person and detain him briefly for questioning upon suspicion that he may be connected with criminal activity. Upon suspicion that the person may be armed, the police should have the power to “frisk” him for weapons. If the “stop” and the “frisk” give rise to probable cause to believe that the suspect has committed a crime, then the police should be empowered to make a formal “arrest,” and a full incident “search” of the person.

It seems pretty clear to me that the sheriff overstepped his authority, though his request for the subject to keep his hands out of his pockets is one reasonable part of the exchange. Appeals to patriotism make for good sound bites, but are no excuse for stomping on rights, or for threatening someone.

I suspect that the average innocent person stopped by the police has some sense of civic duty, and wants to assist them if they can; I know I would have this feeling. Or they may feel that since they have done nothing wrong, there’s no harm in trying to clear themselves — certainly a common theme on some of the crime dramas I watch on TV*. But these are the rights that you have in the US, and while I respect the police and recognize that they have a tough job, the proximity with Veterans’ Day reminds me that plenty of people served in the military and fought in wars to secure and preserve these rights, and that just giving them away and letting them be trampled on would not be the proper way to show them the respect and gratitude they deserve.

*I have to wonder if defense attorneys ever watch shows like CSI or Law & Order as drinking games — drink whenever they violate someone’s rights or do anything else that would render evidence inadmissible. I suspect there are times they’d be blotto by the second commercial break.