Choprafication: The act of adding of “quantum” to a description to make it sound all science-y and stuff

Me (no relation)

Quantum and Consciousness Often Mean Nonsense

I hold degrees in physics and have spent a lot of time learning and teaching quantum mechanics. Nonphysicists seem to have the impression that quantum physics is really esoteric, with those who study it spending their time debating the nature of reality. In truth, most of a quantum mechanics class is lots and lots of math, in the service of using a particle’s quantum state—the bundle of physical properties such as position, energy, spin, and the like—to describe the outcomes of experiments. Sure, there’s some weird stuff and it’s fun to talk about, but quantum mechanics is aimed at being practical (ideally, at least).

Yet the mysterious aspects of quantum physics and consciousness have inspired many people to speculate freely. The worst offenders will even say that because we don’t fully understand either field, they must be related problems. It sounds good at first: We don’t know exactly how some things in quantum physics work, we don’t know exactly how to go from the brain to consciousness, so maybe consciousness is quantum.

The problem with this idea? It’s almost certainly wrong.

Time to Update the CV

New Paper

Evaluation of long term performance of continuously running atomic fountains. Metrologia 51 263-269

An ensemble of rubidium atomic fountain clocks has been put into operation at the US Naval Observatory (USNO). These fountains are used as continuous clocks in the manner of commercial caesium beams and hydrogen masers for the purpose of improved timing applications. Four fountains have been in operation for more than two years and are included in the ensemble used to generate the USNO master clock. Individual fountain performance is characterized by a white-frequency noise level below 2 × 10^−13 and fractional-frequency stability routinely reaching the low 10^−16 s. The highest performing pair of fountains exhibits stability consistent with each fountain integrating as white frequency noise, with Allan deviation surpassing 6 × 10^−17 at 10^7 s, and with no relative drift between the fountains at the level of 7.5 × 10^−19/day. As an ensemble, the fountains generate a timescale with white-frequency noise level of 1 × 10^−13 and long-term frequency stability consistent with zero drift relative to the world’s primary standards at 1 × 10^−18/day. The rubidium fountains are reported to the BIPM as continuously running clocks, as opposed to secondary standards, the only cold-atom clocks so reported. Here we further characterize the performance of the individual fountains and the ensemble during the first two years in an operational environment, presenting the first look at long-term continuous behavior of fountain clocks.

I bolded something I harp on occasionally: these clocks are actually run as, and are reported as, clocks. For all of the awesome performance of other devices that grab pop-sci article space, they don’t run continuously and aren’t described as clocks when it comes to the data that get reported to the international standards lab.

Remember, The Simpsons is Fiction

This perpetual motion machine she made today is a joke! It just keeps going faster and faster.

Lisa! Get in here. In this house, we obey the laws of thermodynamics!
– Homer J Simpson


Perpetual Motion Email Guidelines

Short version: no, it won’t work.

“If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.”
— Arthur Eddington, The Nature of the Physical World (1928)


Just Super

A Supertask Shows How Particles Can Spontaneously Start Moving

A particle, traveling at a meter per second, knocks into the square. Because the particle’s speed is a meter per second, and the square is a meter wide, within a second, all the motion that was introduced into the square is gone. But there is no particle ejected. The infinite amount of collisions means there is no final particle. The motion just stops.

The problem with thought experiments is that if they lack rigor, it’s easy to argue into something that is contrary to the laws of physics. With a verbal description, you can get something like Zeno’s paradox, which seems like a contradiction until mathematical rigor is applied.

I think the above is such an example. Somebody has taken a liberty with infinities or made a hand-wavy argument somewhere in the middle of all this. The conclusion violates conservation of momentum and energy, so there’s a flaw somewhere. I’d like to hear more about how the motion ceases after one second. There’s a dodgy assumption in there, I’m sure. There may be an infinite number of particles but they are also infinitely small, so how do you determine their cross-section and the resulting collision rate?

The paper isn’t even that subtle.

What happens at t = 1? By that time, every particle Pi has collided with its immediate left-hand neighbor and so is stationary. Therefore, all the particles are stationary.

Um, what? At that point I confess I stopped reading. This sounds like a technicality of math that doesn’t apply to a real system, i.e. there is no “last particle” that’s moving. If you assume something that is physically impossible, you can come to just about any conclusion you want.

Let's Get Small

Pardon the absence; I’ve spent some time at a DARPA meeting reviewing progress on work being done under the umbrella of DARPA’s efforts to shrink the hardware for devices related to position, navigation and time, known as MicroPNT. I can’t write about any of the details, which is unfortunate because some of the science and engineering is amazing, but you can get an overview of the program and learns some of the particulars:

Microtechnology Comes of Age

Expert Advice: The Chip-Scale Combinatorial Atomic Navigator

Basically DARPA has identified that portable navigation devices that aren’t tied to GPS are important, and are pushing smart people to think about the problem. The program goals are aggressive and each stage progressively so, and they expect the failure rate to be high. But the people involved are scientists, so they understand that research doesn’t always pan out. Such programs allow scientists to try risky things to see if they pan out, and even in failure things are learned.

Listening to all of these talks and visiting the posters has been quite draining.

Monday’s post now seems quite timely, as that seems to be a European effort along these same lines.

Quantum Certainty

Quantum positioning system steps in when GPS fails

The mention that this is based on laser-cooled atoms, with no further details, is a tad frustrating. In grad school I worked on a laser-cooled atom interferometer, which could be used as an inertial sensor. In principle, at least, since the device I worked on was relatively big; the vacuum system was an “L” that was at about a meter in the short dimension and there was a large optical table to generate the laser light. There is more than one way to build such a device, though, and these processes can be made much smaller with engineering effort, so the lack of detail is disappointing.

Not a One-Trick Pony

Millikan, Einstein, and Planck: The Experiment io9 Forgot

I object to the [io9] headline for reasons beyond the cheap sensationalism– it’s also overlooks half of the citation for Millikan’s 1923 Nobel Prize in Physics:

for his work on the elementary charge of electricity and on the photoelectric effect

An important note that Millikan’s prize was not just for the oil drop experiment, and I am in agreement that this analysis (pdf) does a convincing job in debunking this old Millikan-fudged-his-data idea.

How Old Are You? Let's Flip a Coin to Find Out

The predictability of randomness and the age of Earth

The uranium-lead transition isn’t the only one used. There’s also the rubidium-strontium transition (with a half-life of 49 billion years), the potassium-argon decay (1.3 billion years), and a handful of others. The key in all these cases is to have a rock — meteorite or otherwise — with enough atoms of the given types to perform measurements. One we don’t see in the list is “carbon dating”: carbon-14 has a half-life of about 5,700 years, so it’s useful for archaeology and dating the remains of animals from the relatively recent past, but utterly useless for measuring the age of Earth.

But why is a random process like radioactive decay useful as a clock?

What…Do You…Mean by That? I…Have to Know!

Please Don’t Beam Me Up, Scotty

Visitor: It doesn’t transport. It disassembles your molecules and reassembles them on the other side. It annihilates you, and builds a perfect copy in a new location. It’s not a transporter, it’s a replacer. What results is a facsimile, a reproduction, a brand-new being with borrowed memories. The original creature—its consciousness—its soul—all gone.

This is funny, and mostly right. But there’s one physics error I spotted, and it’s a whopper. As you might guess, it ties in with the details of quantum teleportation. It’s unfortunate, too, because I think much of the story holds together without it.

Visitor: Think about it. It’s not the actual molecules being “transported,” just information about them. You could just as easily transmit that information—and build the new being—while leaving the old one perfectly intact. Couldn’t you? And if the old one persisted, wouldn’t it be obvious that the new copy is a different being altogether?

Spock: His analysis is not incorrect, Captain.

What Spock should have said was that the answer is “no”; i.e. there’s a superfluous “not” in there (a sign error, of sorts). Destruction of the state of the original is a requirement of quantum teleportation, which renders the rest of that section’s argument moot. Perfect copying while retaining the original is cloning and there is something called the no-cloning theorem in quantum mechanics: basically, you can’t make copies of an unknown quantum state (the wikipedia page on this gets technical pretty quickly). You can transfer that information from one particle to another, but the information in the original is destroyed.

The gory details of this bit of theory is tad outside of my wheelhouse, but as I understand it if you could clone, then you could measure the cloned state without disrupting the original. But there are a whole bunch of quantum effects that depend on a state being undetermined, rather than having some underlying reality — there must be more than one possible state in order to see interference. It’s a reason that classical explanations for entanglement fail, because in classical physics you can have an unknown state (a coin you’ve flipped) and then measure it (look at the coin, see it’s “heads”), and you will know that it was heads even before you looked at it. In QM, you don’t know that it was heads until the moment of measurement — it was in a superposition of heads and tails before that, and that superposition will behave differently than a state that was secretly heads (or tails) the whole time.

I Hope This isn't a Scam

This Nigerian College Student Built a Wind- And Solar-Powered Car From Scraps

I’ve run numbers for a solar-powered car before, when someone had proposed just popping solar cells on a car and thinking that would be viable. It won’t work. It’s not really close, so even with a head start of charging the battery up, I have to wonder what you’re going to get.

Gasoline has an energy density of around 120 MJ/gallon. Let’s convert this into units used in electrical systems: 1 kW-hour is 3.6 MJ, so a gallon of gas is a little over 30 kWh of energy. Electrical systems are much more efficient than internal combustion, so let’s assume we only need 10 kWh of electricity to do the work of a gallon of gasoline (which also might require things like regenerative braking). Comparing to a 30 mpg gasoline engine, this is 3 miles/kWh, which is about what commercial electric cars are getting.

According to maps I found, solar insolation in the US is highest in the southwest, peaking above 5 kWh/m^2/day, and I think that assumes your panels track the sun to keep it perpendicular to the panel. The solar panel on the car looks to be about 2 square meters, so we can get around 10 kWh with a full day’s charge — we can replace about a gallon of gas. Nigeria’s insolation is higher, so let’s multiply this insolation by 2, but the claim is that this happens in 4-5 hours, so maybe that’s a wash. And the panel doesn’t track the sun, so this is probably generous.

Can you get around town in something like that? Sure. You can go 30 miles in a day on a charge, plus whatever charging you get as you’re out and about. But then you’ll have a depleted battery, and wouldn’t be able to do this every day since you can’t charge it at night. Unless you’re going under 10 mph and it’s always sunny, this can never be a “charge-as-you-go” system without an order-of-magnitude improvement somewhere.

There’s also this, which sets off the skeptic alarm in a much stronger fashion:

Not only did Oyeyiola install a giant solar panel on top of the Beetle; he also inserted a wind turbine under the hood. As Preston explains, that allows air to flow into the grill while the car is moving, subsequently turning the turbine’s rotors and charging the battery at the back of the car. Oyeyiola also built a strong suspension system to deal with the weight of the battery itself.

Unless this is just a really poor description of something else, it sounds an awful lot like a perpetual motion machine — using the wind generated by your motion to charge the battery. Realistically, such a device should drain the battery faster, because it can’t be 100% efficient.