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Photo First: Light Captured As Both Particle and Wave
mpicpp sends word that scientists have succeeded in capturing the first-ever snapshot of the dual behavior of light. "It's one of those enduring Zen koans of science that we've all grown up with: Light behaves as both a particle and a wave—at the same time. Einstein taught us that, so we're all generally on board, but to actually understand what it means would require several Ph.D.s and a thorough understanding of quantum physics. What's more, scientists have never been able to devise an experiment that documents light behaving as both a wave and a particle simultaneously. Until now. That's the contention of a team of Swiss and American researchers, who say they've succeeded in capturing the first-ever snapshot of light's dual behavior. Using an advanced electron microscope – one of only two on the planet – at the EPFL labs in Switzerland, the team has generated a kind of quantum photograph of light behaving as both a particle and a wave. The experiment involves firing laser light at a microscopic metallic nanowire, causing light to travel — as a wave — back and forth along the wire. When waves traveling in opposite directions meet, they form a "standing wave" that emits light itself — as particles. By shooting a stream of electrons close to the nanowire, the researchers were able to capture an image that simultaneously demonstrates both the wave-nature and particle-nature of light. 'This experiment demonstrates that, for the first time ever, we can film quantum mechanics — and its paradoxical nature — directly,' says lead researcher Fabrizio Carbone of EPFL, on the lab's project page. The study is to be officially published this week in the journal Nature Communications."
every dual slit experiment shows light behaving as both particle and wave, because every photon only interferes with itself. Two or more photons never interfere with each other.
If you attempt to measure it in the way you would measure a wave, it will present itself as a wave.
If you attempt to measure it in the way you would measure a particle, it will present itself as a particle.
Light doesn't choose to be a particle or a wave at any given time, the measurement we use defines the characteristics it has. Nothing more, nothing less.
From the fine article it provides a caption to the graphic
"The bottom "slice" of the image shows the particles, while the top image shows light as a wave""
Looking at the graphic the top image is a 3-D display and the bottom just a color coded 2-D representation with topo lines. I see nothing in this displaying the wave aspect and particle aspect. Mistake?
There's no way of doing that. Feynman said "I think I can safely say that nobody understands quantum mechanics". You've probably got no chance. :-)
I have seen these images so many times before. Standing waves, traveling waves, plane polarized wave entering a ferrite core and its plane of polarization turning and twisting, all in glorious 24 bit color. But all those images and animations came from Ansoft High Frequency Structure Simulator software. Not actual experimental physically observed phenomena. And not at light frequencies. Microwave wavelengths mostly. So seen it so many times before, but definitely not meh.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
> but to actually understand what it means would require several Ph.D.s and a thorough understanding of quantum physics
No, just some understanding of statistics and calculus up to tensors along with an ability to know why you know something rather than just knowing things.
When we make out relatively simple things (like quantum physics) to be complex, when in fact they are just strange we do a disservice to those who might otherwise put in the effort to understand.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Light behaves as both a particle and a wave—at the same time. Einstein taught us that, so we're all generally on board, but to actually understand what it means would require several Ph.D.s and a thorough understanding of quantum physics
Stop pretending physics is spooooky. It's not that difficult to understand, at least at a superficial level. And I don't have a degree, let a lone a Ph.D, but even I can explain it (again, superficially):
Time dilation means that the faster you go, the slower time goes. If you're travelling at the speed of light in a vacuum, then the speed at which you're travelling through time is slowed infinitely. This means a photon experiences no passing of time between the moment it is created, and the moment it collides with something.
But the speed of light is finite, so it has to travel through time to go between two points. But because from the photon's perspective it's travel is instantaneous, it can't experience that time. So a photon doesn't know where it's going to land, until it does. And so until it does land, it could have landed anywhere. So when a photon is created, it travels out in all directions, like a wave, until it lands somewhere and the wave collapses.
The part that's hard to understand is the why.
A group of physicist-journalists have done an interesting experiment to show how light trapped in a tiny wave guide interacts with electrons. They then massively overhyped the results by making claims that are highly dubious at best in order to gain attention.
It is not theoretically possible to both capture a single photon as both a wave and particle simeltaneously. What they have done is show a set of thousands (millions?) of electron photon interactions at the same instant in time arranged on 2 axis. Basically the lower and slower lumps become particles and the upper smoother lines show waves. So its neat and a first for light waves afaik but misleading as it is not a photo of a single photon.