8 ms·
First photograph of light as both a particle and wave (2015)
- deckar01 10y agoIt took me a few reads for this to sink in. Quantum interference causes standing waves. Electron-photon particle collisions cause detectable energy release. The particle collisions occur in an interference pattern.
- EarthIsHome 10y agoYes, and the colors describe the speeds of the particles as a result of tbe electron-photon collisions. It's not necessarily the particles we're seeing, just the particle behaviors from their collisions.
- shshhdhs 10y agoThis is really cool! What's the reason for the blue & violet colors to be raised more than others in the wave? Is it just the timing of the snapshot? As in, another picture might show another color at the top of the wave? Or is the standing wave "stuck" in that position?
- mdturnerphys 10y agoThat's just the color scale they've used for the z axis.
- nsxwolf 10y agoIt didn't explain the picture.
- leksak 10y agoYeah, I don't know how to interpret it. It's not immediately obvious to me that I'm looking at a wave and particles at the same time.
- initram 10y agoNor does it appear to be a photograph. It looks very much like a 3D rendering with false coloring.
- mikekchar 10y agoYour eyes don't have quantum energy packet receptors :-) A normal photograph is made by bouncing light off something and detecting it. If you are using a CCD, you are still using false colour. It just happens to correspond to the true colour. In this experiment, the electrons interact with the photons to produce quantum energy packets, which the microscope detects. What is the colour of the quantum energy packets? The question has no meaning, because they aren't light. Since the colour is arbitrary, they can choose to colour it in any way they find useful. Having said that, I also don't understand the "photograph".
- smallnamespace 10y ago> Your eyes don't have quantum energy packet receptors Actually, we do, so long as that energy is in the form of photons [1]. [1] http://www.nature.com/news/people-can-sense-single-photons-1.20282 http://www.nature.com/news/people-can-sense-single-photons-1...
- pitaj 10y ago> so long as that energy is in the form of photons Of a particular range of frequencies
- URSpider94 10y agoWhat the image represents is the energy loss/gain of a whole bunch of electrons that interact one at a time with a light wave traveling along a tiny metal wire (we call this kind of captive light wave a "phonon"). For each electron fired at the wire, it can either pass through unscathed, or it can interact with an electron and scatter off with a different energy, like two billiard balls hitting each other. The collision is fundamentally a collision between two particles. However, the fact that the properties of the collisions vary sinusoidally along the length of the wire imply that the photon is also acting like a wave oscillating up and down the wire. I disagree that this is the "first time" that we've observed simultaneous wave-particle behavior, you can see the same thing by firing photons at two narrowly-placed slits. This results in a diffraction pattern as if the photons were interfering like waves, but we can confirm that we're detecting single photons at the detector, and you can even confirm that each photon travels through one slit or the other ... See https://en.wikipedia.org/wiki/Double-slit_experiment https://en.wikipedia.org/wiki/Double-slit_experiment
- _nalply 10y agoSwiss here. The École Polytechnique Fédérale de Lausanne (EPFL), where this experiment has been carried out, is one of the two federal institutes of technology, the other one is the Eidgenössische Technische Hochschule Zürich (ETHZ). https://en.wikipedia.org/wiki/%C3%89cole_Polytechnique_F%C3%A9d%C3%A9rale_de_Lausanne https://en.wikipedia.org/wiki/%C3%89cole_Polytechnique_F%C3%... https://en.wikipedia.org/wiki/ETH_Zurich https://en.wikipedia.org/wiki/ETH_Zurich
- emerongi 10y agoIt's hard to grasp what was really captured on that image, but this still doesn't rule out the pilot wave theory. I think it's misleading to call it a photograph of light "as both a particle and wave".
- hclivess 10y agoI came here to say fueck offf und die
- posterboy 10y agoDarn the ambiguous english language, do they mean the photograph is a particle-wave? because that wouldn't be a first. /s
- msimpson 10y agoThis article is much more clear on what the image actually represents: http://www.livescience.com/50019-image-light-wave-particle.html http://www.livescience.com/50019-image-light-wave-particle.h... "A clever technique and an ultrafast electron microscope have caught an image of light behaving as both particle and wave at the same time. Here, the wave nature is demonstrated in the wavy upper portion, while the particle behavior is revealed below, in the outlines showing energy quantization." Credit: Fabrizio Carbone/EPFL Also, this was all published on March 2, 2015.
- amelius 10y agoI have a question about QM, which perhaps somebody here can answer: Is quantization an inherent property of the photon, or is it a property of the material (or of the interaction with it)?
- tehwalrus 10y agoIf I remember correctly, quantisation occurs because of the solutions to certain differential equations in the geometry (eg of an atom, of a lasing chamber, etc). The quantised states are the different solutions to that equation (the different energy levels + spin states in an atom.) - this holds for electrons in atoms being quantised. The photoelectric effect, which has to do with incident photons, showed that you can't turn up the intensity of long wavelength light and ping electrons off things: the power input didn't change things, but a very low power of short wavelength photons did. Thus, Einstein concluded that there must be something specific about the energy of individual particles, not just the total energy stored in a wave. So it is observed in an interaction, but the information defining the final effect travels with the photon.
- pitaj 10y agoI believe that the quantization of the photon is directly related to the idea the electrons can only move between discrete energy levels in their respective atoms.
- deleted 10y ago[deleted]
- deleted 10y ago[deleted]
- deleted 10y ago[deleted]
- mzs 10y agohttps://www.eurekalert.org/pub_releases/2015-03/epfd-tfe030115.php https://www.eurekalert.org/pub_releases/2015-03/epfd-tfe0301...
- Koshkin 10y ago> an exchange of energy "packets" (quanta) between electrons and photons I thought that photons are the energy quanta (that electrons can absorb or lose).