#particle-wave duality

[nuanimistdatabase]

Article: First image of the shape of a single photon revealed in light study

First image of the shape of a single photon revealed in light study

[wikipediagrams]

[random2908]

The photoelectric effect is not an unequivocal demonstration of the particle nature of light. It can also be explained with entirely wave-based light, but discrete energy levels in materials. (The math is uglier that way, but it can be done.)

I had a professor who hated that that’s always the go-to example of light being particles, and that peeve basically rubbed off on all of his students.

There are, in fact, a couple of phenomena that can only be explained by saying light is particles. If there weren’t then--if everything could be sufficiently explained by waves and invoking particles only made the math easier, as is the case in the photoelectric effect, then we’d say light is just a wave and treating it as a particle is just a mathematical trick. (In fact, as far as has been discovered so far, this is the situation with sound--that there are phenomena where calling it a particle makes the math easier but there aren’t any known phenomena where calling it a particle is absolutely necessary.)

So stop using it as an example.

(Plus it’s also a dumb example for explaining to lay people because how many random people actually know what the photoelectric effect even is.)

[non-existentbandnames]

I was sitting around eating donuts and listening to cassettes with my friend when he told me about this new band out of Copenhagen that sounds like The Slits. I’m always in the market for more Slits-esque post-punk, so he tosses me the s/t tape and I am immediately rolling on the floor dying because the band is called The Double Slits and they are from Copenhagen. My friend (not a scientist) did not get it. That’s all expositional to say, the five piece from Copenhagen seriously knows where their sound fits within the punk schema in addition to knowing their quantum mechanics history and the importance of their home town in the development of such things as atomic bombs and iPhones (listen to their song “iPhones and A-Bombs (Not With a Bang)” for more information).

Recommended for: nerds who like party-cull-rave duality (horrible pun, sorry) and are looking for a new band with a sort of folksy/Slits sound.

[mirrorontheworld]

Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists have succeeded in capturing the first-ever snapshot of this dual behavior.

[fritfilter]

>Wave-particle duality is the idea that a quantum object can behave like a wave, but that the wave behaviour disappears if you try to locate the object. >...The quantum uncertainty principle is the idea that it's impossible to know certain pairs of things about a quantum particle at once. For example, the more precisely you know the position of an atom, the less precisely you can know the speed with which it's moving. It's a limit on the fundamental knowability of nature, not a statement on measurement skill. The new work shows that how much you can learn about the wave versus the particle behaviour of a system is constrained in exactly the same way. Kinda like how 2 * 1, 4 / 2, 1 + 1 and 5 - 3 are all just representations of 2.

[chroniclesofachemist]

confinement of electrons to quantum corrals on a metal surface It both shows the existence of the atoms AND the duality of electrons in one image. That's fantastic. 

[cozydark-blog]

Paths of Photons Are Random -- But Coordinated |

Researchers at the Niels Bohr Institute have demonstrated that photons (light particles) emitted from light sources embedded in a complex and disordered structure are able to mutually coordinate their paths through the medium. This is a consequence of the photons' wave properties, which give rise to the interaction between different possible routes.

The results are published in the scientific journal Physical Review Letters.

The real world is complex and messy. The research field of photonics, which explores and exploits light, is no exception, and in, for example, biological systems the statistical disorder is unavoidable.

Drunken people and photons

"We work with nanophotonic structures in order to control the emission and propagation of photons. We have discovered in the meantime, that inevitable inaccuracies in the structures lead to random scattering. As a consequence, the transport of photons follow a random path -- like a drunken man staggering through the city's labyrinthine streets after an evening in the pub," explains David García, postdoc in Quantum Photonics at the Niels Bohr Institute at the University of Copenhagen.

If we continue with this analogy, then it is not certain that just because one drunken man comes home safely, then a whole crowd of drunken people spreading out from the pub will also find their way through the city's winding streets. There is no relationship between the different random travellers.

But there is when you are talking about photons. They can 'sense' each other and coordinate their travel through a material, according to new research.

"We have inserted a very small light source in a nanophotonic structure, which contains disorder in the form of a random collection of light diffusing holes. The light source is a so-called quantum dot, which is a specially designed nanoscopic light source that can emit photons. The photons are scattered in all directions and are thrown back and forth. But photons are not just light particles, they are also waves, and waves interact with each other. This creates a link between the photons and we can now demonstrate in our experiments that the photons' path through the material is not independent from the other photons," explains David García. continue reading

[wordjamming]

nawwww

[cozydark-blog]

Particle and Wave-Like Behavior of Light Measured Simultaneously |

What is light made of: waves or particles? This basic question has fascinated physicists since the early days of science. Quantum mechanics predicts that photons, particles of light, are both particles and waves simultaneously. Reporting in Science, physicists from the University of Bristol give a new demonstration of this wave-particle duality of photons, dubbed the 'one real mystery of quantum mechanics' by Nobel Prize laureate Richard Feynman.

The history of science is marked by an intense debate between the particle and wave theories of light. Isaac Newton was the main advocate of the particle theory, while James Clerk Maxwell and his greatly successful theory of electromagnetism, gave credit to the wave theory. However, things changed dramatically in 1905, when Einstein showed that it was possible to explain the photoelectric effect (which had remained a complete mystery until then) using the idea that light is made of particles: photons. This discovery had a huge impact on physics, as it greatly contributed to the development of quantum mechanics -- the most accurate scientific theory ever developed.

Despite its success, quantum mechanics presents a tremendous challenge to our everyday intuition. Indeed, the theory predicts with a remarkable accuracy the behaviour of small objects such as atoms and photons. However, when taking a closer look at these predictions, we are forced to admit that they are strikingly counter-intuitive. For instance, quantum theory predicts that a particle (for instance a photon) can be in different places at the same time. In fact it can even be in infinitely many places at the same time, exactly as a wave. Hence the notion of wave-particle duality, which is fundamental to all quantum systems. continue reading