0967: Prairie

[rhomboidal]

Earlier, they were pondering the "expanding spacetime" skies.

[PM 2Ring]

Ooooooh. I'd always wondered what a "graser" was. Now I know.

I heard Kansas was trying to weaponise their remaining bison, though, into a sort of counter-grazer.

I suspect that this involves careful interbreeding with dairy cows, in an attempt to produce a Bise-Holstein condensate. As any agri-quantum mechanic knows, you need high quality bisons to make a livestock laser, there's no point trying to use cheap farmions to achieve a lasing action because they obey the Poorly Exclusion Principle.

[project2051]

I'd much prefer "America the Beautiful" as our national anthem.

Isn't it already someone else's national anthem? I know a bunch of our patriotic songs are knockoffs of other countries' patriotic songs.

Not that one. Which is all the more reason it should be the anthem. Maybe you're thinking of "My Country, 'Tis of Thee" (God Save The Queen), which was the anthem for a while.

I don't mind the "The Star-Spangled Banner", but for an anthem I prefer "My Country, 'Tis of Thee" over "America the Beautiful". Though I can't sing it anymore without lapsing into "The Kilted Yaksmen".

[drachefly]

Ooooooh. I'd always wondered what a "graser" was. Now I know.

I heard Kansas was trying to weaponise their remaining bison, though, into a sort of counter-grazer.

I suspect that this involves careful interbreeding with dairy cows, in an attempt to produce a Bise-Holstein condensate. As any agri-quantum mechanic knows, you need high quality bisons to make a livestock laser, there's no point trying to use cheap farmions to achieve a lasing action because they obey the Poorly Exclusion Principle.

And you can't just use wild bison either - cow tipping is the mechanism of population inversion.

[jqavins]

I'd much prefer "America the Beautiful" as our national anthem.

Isn't it already someone else's national anthem? I know a bunch of our patriotic songs are knockoffs of other countries' patriotic songs.

Not that one. Which is all the more reason it should be the anthem. Maybe you're thinking of "My Country, 'Tis of Thee" (God Save The Queen), which was the anthem for a while.

I don't mind the "The Star-Spangled Banner", but for an anthem I prefer "My Country, 'Tis of Thee" over "America the Beautiful". Though I can't sing it anymore without lapsing into "The Kilted Yaksmen".

Just for the record, that song with the tune of "God Save the Queen(King)" is called "America". (Not to be confused with Paul Simon's "America" - which has the tune of hymn that was also borrowed by Bach for a number of choralles, but I digress - and probably a dozen or more other songs.)

I don't mind "The Star-Spangled Banner" for the national fight song, but for an anthem I'd prefer "America the Beautiful."

[neoliminal]

I...don't think I'm smart enough to understand this one. Not even after reading (more like scanning, really) the Wikipedia article on the Copenhagen Blah Blah Blah Interpretation Words.

Here, let me simple that for you.
http://simple.wikipedia.org/wiki/Universe
http://simple.wikipedia.org/wiki/Double-slit_experiment

[Eshru]

Nobody mentioned that Geico commercial?

Both making points about how something is observed and presented affecting how we see it?

Edit: And both riffing on the same line of the same song or it wouldn't be worth mentioning.

[bmonk]

Wouldn't that be "gasar" instead of "lasar?" I know for some people here, the more serious question is going to be "Wouldn't that be 'gasar' instead of 'lasar'?"

I'd use "GrASAR": GRain Amplified by the Stimulated Emission of Rice.

On a related note--sort of--in this world, does Quantum Chromodynamics use purple-amber-gold as the colors?

[toastking]

Don't destroy Kansas! They have good barbecue!

[SpringLoaded12]

I really don't get the joke at all (I did more or less understand the science explanations here, but I still don't get how they're supposed to make this a "joke" proper), but I really enjoy the art. The finak product looks like a truly worked-on drawing, not like a bunch of "stylish" Photoshop filters applied on some crap smudges. Randall could do this kind of thing a lot more often.

Agreed.

Although, it should be noted that not all Photoshop works are lazy attempts at being "stylish." I have seen some beautiful drawings made from scratch in Photoshop using a tablet, and mostly using the paintbrush tool. I know that's not what you said, and probably not what you meant, but I feel like it's worth noting nonetheless.

But were you suggesting that Randall normally uses Photoshop filters? Honest question there, I'm a bit confused. I haven't seen any evidence to suggest that, but I was never very good at spotting Photoshopped images.

[Moose Anus]

But were you suggesting that Randall normally uses Photoshop filters? Honest question there, I'm a bit confused. I haven't seen any evidence to suggest that, but I was never very good at spotting Photoshopped images.

I can tell from some of the pixels, and from seeing quite a few 'shops in my time.

[MartianInvader]

This comic and thread have inspired me to learn more about quantum cornfield theory.

[furyguitar]

I don't know about you, but I have really enjoyed the use of color in the last 3 out of 4 comics (Airbender, Pink Floyd poster, and this one). They have really brought the emotion wrought to a new level.

[project2051]

This comic and thread have inspired me to learn more about quantum cornfield theory.

Kind of off the grain topic, but don't forget to do some research on the string bean theory.

[ASW]

As a Nebraskan I generally oppose the alt text Although it would be wicked cool to see.

As a sooner fan I have to hope they hurry with that laser! *grin*

Hey you will be next if they get us, lord knows they cant get us in sports.

[Coyne]

All I can say is that quantum mechanics + culture ==> completely surreal!

[Pfhorrest]

I recently read, and now cannot find, a rather amusing bit of fiction about an alternate universe where the Everett (many-worlds) interpretation became dominant before the Copenhagen (waveform-collapse) interpretation did, and the latter is now (in said alternate universe) considered a crazy crackpot theory.

Here it is, starting in the fifth paragraph

Yep! That's the one. Thanks!

[ijuin]

What is this "collision" thing? If we just focus on Schrondinger's equation you'll see no such thing is represented anywhere. All wavefunctions evolve smoothly. Where does the classical world come from? Everrett never explains why we aren't aware of other worlds--he just takes for granted that we aren't. But why aren't we? Components of our initial wavefunction are entangled with different components of the scattering particle's wavefunction, but how come we're only aware of ONE such set of components? Decoherence approaches say we are only aware of quantum effects via what amounts to interference phenomena, and so when they go away we are no longer aware of them, but again, how come?

No quantum interpretation does anything but obfuscate and dance around the fundamental question, which is why we are only aware of the classical world, and why there is an entire phenomenological substrate--the world described by classical physics--that obeys rules (causality, locality) that are not part of the quantum corpus. This is the central mystery, and contra Penrose et al it is clear that consciousness is a purely classical phenomenon: if it wasn't we'd be aware of the quantum world, whereas manifestly we are not.

The question is not "why is the quantum world so weird?" but "why is there a classical world at all?"

For macroscopic objects, the scale of the uncertainty in time/space/energy becomes smaller than the practicable errors in accuracy of measurement. For example, would you really notice (or even be able to detect without apparatus capable of molecular-scale precision) if there was an uncertainty of a few nanometers in the location of an automobile? On the human scale, quantities smaller than a micrometer/nanogram/microsecond are pretty much irrelevant.

It's only when we make the gross state of a macroscopic system dependent on a single-particle event, as in Schrodinger's Cat, that quantum effects aren't lost in the noise and rounding errors.

[StClair]

Seems to me that Colorado would be better off weaponizing their purple mountains, which are of shorter wavelength and higher energy.

[Pfhorrest]

It's only when we make the gross state of a macroscopic system dependent on a single-particle event, as in Schrodinger's Cat, that quantum effects aren't lost in the noise and rounding errors.

And this is how sensitivity to initial conditions -- the ability for a small change in one of many input variables to produce a large change in the output - came to be called "chaos": because it amplifies randomness. All those many microscopic variables are constantly changing (and, accounting for quantum effects, aren't really precisely determined to begin with); a chaotic system, like the Schdrodinger's Cat box, amplifies those unknowns (or unknowables) up to the macroscopic scale, instead of them all mostly cancelling out as they do in less chaotic systems, giving us difficult (or impossible) to predict behavior at scales that really matter to us.

[Mirage_GSM]

Isn't it ironic that the hard part about understanding this comic wasn't quantum physics but the lyrics to some song that probably every American child knows?

[mric]

Isn't it ironic that the hard part about understanding this comic wasn't quantum physics but the lyrics to some song that probably every American child knows?

Perhaps not ironic, but worth pointing out nonetheless. I didn't get the reference to the song, and didn't even know I had missed a part of the joke, since it makes reasonable sense if you consider the character to have been speaking poetically. Having just read the words, I can understand why it is not well known outside the US. It's the sort of poem only a mother could find beautiful.

[Velo Steve]

This brought out the loudest laugh I have emitted in a while.

As a University of Colorado Ph.D. I can say that the amber wave laser is completely plausible - or at least the motivation is.

[BigglesPiP]

The clouds are slowly moving to the right.

I'm not sure how you managed that, or if it was even intentional?

[cilix42]

What I have never really understood in discussions about the wave/particle duality is why it is valid to treat a macroscopic object (say, a baseball) as a single "particle" when clearly it is composed of many tiny particles. So how can we speak about "the wave corresponding to the baseball"?

Apologies for this probably more than trivial question, but it's bugged me for a long time and I already found some of the comments here very illuminating so I'm hoping for more of the sort. It's probably something to do with the superposition of all the "small" waves of the individual particles, but for some reason I find all this quite handwavy [1]. Then again, all my knowledge about quantum physics stems from popular science books which I read more than ten years ago so I guess just going through an introductory textbook would make a lot of things clearer and more precise. Does anyone have recommendations for a good introduction to quantum mechanics for someone with a thorough background in maths but only rudimentary knowledge of (even basic) physics?

[1] Thinking about it again the reason for this is probably that when I think of waves (like water waves or light waves) I don't really think of them interacting apart from superposition, so my intuition says that even if many "tiny" waves superimpose to form the "big" wave of a macroscopic object, that object will instantaneously fall apart because the waves "move on". Hmm, seeing this written down makes me aware of how much nonsense that probably is because if waves correspond to particles then of course they must be able to interact. I suppose this interaction is governed by the Schroedinger equation? (I'm guessing here, I have no idea what that equation actually says.)

[nevis]

I wasn't familiar with the song, thus didn't get the joke. Oh well. Learned something new.

[zer]

Hi, first post here.

I got the quantum mechanics joke but, not being from the US, I really didn't get the song reference. I could only think of Tori Amos's song "Amber Waves" (on Scarlet's Walk), which didn't seem very appropriate -- the song tells about a porn star. But I liked the scenery.

[Wnderer]

Good thing xkcd got that wave/particle joke in, before they go obsolete.

Now, using a technique known as "weak measurement", Steinberg and his research team say they have managed to accurately measure both position and momentum of single photons in a two-slit interferometer experiment.

http://physicsworld.com/cws/article/news/46193

[Paranord]

Now I'm worried that the Sangre de Cristo Mountains are approaching REALLY fast.

[zjxs]

Australia, the world's 5th largest wheat exporter, already condenses grain waves into packets. We're getting very good at sending them over distances. Watch out.

[soren121]

Methinks Randall made use of Photoshop's grass brush. I've always thought it was weird that Photoshop comes with a grass brush.

[ijuin]

What I have never really understood in discussions about the wave/particle duality is why it is valid to treat a macroscopic object (say, a baseball) as a single "particle" when clearly it is composed of many tiny particles. So how can we speak about "the wave corresponding to the baseball"?

AFAIK, the uncertainties in the positions and motions of the particles that comprise the baseball are so small (less than a micron for any reasonably probable events) that on the scale of the entire baseball, they can be disregarded, since we almost never care about measuring the baseball to that degree of precision.

[scarletmanuka]

What I have never really understood in discussions about the wave/particle duality is why it is valid to treat a macroscopic object (say, a baseball) as a single "particle" when clearly it is composed of many tiny particles. So how can we speak about "the wave corresponding to the baseball"?

"Particle" doesn't necessarily mean "fundamental and indivisible particle". It can be used to describe anything that is on the "particle" end of the wave-particle spectrum: that is to say, anything that behaves and moves more or less like a single object, highly localised in a particular region of space at any given time.

Thinking about it again the reason for this is probably that when I think of waves (like water waves or light waves) I don't really think of them interacting apart from superposition, so my intuition says that even if many "tiny" waves superimpose to form the "big" wave of a macroscopic object, that object will instantaneously fall apart because the waves "move on". Hmm, seeing this written down makes me aware of how much nonsense that probably is because if waves correspond to particles then of course they must be able to interact. I suppose this interaction is governed by the Schroedinger equation? (I'm guessing here, I have no idea what that equation actually says.)

If you particularly want to consider a baseball or some such object as a collection of particles and look at the effect of all the other particles on one particular particle, then yes, you could model it like that and the effects would be bundled into the potential term in Schroedinger's equation. I don't know whether that would be a very illuminating approach though.

[descent]

http://www.newscientist.com/article/mg21228362.600-lets-dare-to-question-quantum-magic.html

[Denswei]

Ah....
So a grain combine (ie, grain harvester) merely collapses the wave function of the (grain) field so that it is observed as particles of grain, instead of waves of grain?
And so the particles of grain subsequently enter a particle smasher to be broken into sub-grain particles, which reassemble into tasty macro-scale grain-assemblages?

[scarletmanuka]

So a grain combine (ie, grain harvester) merely collapses the wave function of the (grain) field so that it is observed as particles of grain, instead of waves of grain?
And so the particles of grain subsequently enter a particle smasher to be broken into sub-grain particles, which reassemble into tasty macro-scale grain-assemblages?

Ultimately, of course, they are usually assembled as grain packets.

[Archgeek]

So whenever a physicist says "observe", mentally replace it with "hit with shit".

The waveforms collapses when hit with shit.
When you hit a photon wave with shit it collapses into a particle.

...Troublingly, that makes it sound like they're throwing poo at the waves, monkeyways.

[Eogan]

So whenever a physicist says "observe", mentally replace it with "hit with shit".

The waveforms collapses when hit with shit.
When you hit a photon wave with shit it collapses into a particle.

...Troublingly, that makes it sound like they're throwing poo at the waves, monkeyways.

Once again I submit that this is more understandable and easier to identify with than what particle physicists normally do.