shirgall Posted November 16, 2015 Posted November 16, 2015 http://phys.org/news/2015-03-particle.html 1
A4E Posted November 16, 2015 Posted November 16, 2015 I probably need some animation to understand this fully. They are taking 2 sources of light and making them interact, so the title on that article is misleading. If it was truly a photograph from the same source of light, (which it appears it is not), then the title would be correct. Interesting and cool maybe yes. Breakthrough, no. The researchers themselves probably never stated that it was a photography of the same light source, but the article author decided that would be a sensational title.
Carl Green Posted November 16, 2015 Posted November 16, 2015 It would be nice if the field of scientific journalism kicked the precision of language up a notch. I think that too often the author uses incorrect terminology to "dumb things down for the lay man". This is how we end up with most people thinking atoms actually look like all those graphical representations when really you'd never be able to 'see' a complete atom even if you were scaled down to its size (if current atomic model theories are correct.) I'm by no means 'scientifically smart', but that's not a photograph, for starters. 1
Mister Mister Posted November 16, 2015 Posted November 16, 2015 Yes I think that this is a little misleading to call this a photograph, rather than some computer model based on measurements. I'm not sure what I'm really looking at. Also, I thought the whole idea about the Copenhagen Interpretation, and Quantum Logic, was that light exists in a state of contradictory or non-identity, until it is measured. In other words, you CAN'T measure light as both particle and wave, you can't picture it, you can't model it, except as mathematical abstraction. Am I wrong?
Carl Green Posted November 17, 2015 Posted November 17, 2015 Yes I think that this is a little misleading to call this a photograph, rather than some computer model based on measurements. I'm not sure what I'm really looking at. Also, I thought the whole idea about the Copenhagen Interpretation, and Quantum Logic, was that light exists in a state of contradictory or non-identity, until it is measured. In other words, you CAN'T measure light as both particle and wave, you can't picture it, you can't model it, except as mathematical abstraction. Am I wrong? I struggled through some of the original source paper. I *think* that the graphic shown above is the result of both electrons and photons, from differing sources, being 'shot' at a nanowire suspended on/by graphene and appearing in the same space. And the two results are transposed together based on the time axis. So, it's not necessarily 'single original' 'units' of light being split and imaged, but the two different things reacting to the same thing at the same time.
Pelafina Posted November 18, 2015 Posted November 18, 2015 How can one thing be two different things simultaneously? Isn't the rule of philosophy, that concepts have to be logical as well as the evidence be empirical. This fails the logical test. Why is no one here catching this? 1
shirgall Posted November 19, 2015 Author Posted November 19, 2015 How can one thing be two different things simultaneously? Isn't the rule of philosophy, that concepts have to be logical as well as the evidence be empirical. This fails the logical test. Why is no one here catching this? The exclusion principle requires something to not be two different things in the same sense. The properties of light as a particle or a wave are not the same sense, which was the difficult hump to get over. No one here is "catching this" because evidence of the properties of light is so easily replicated. It clearly does have the properties.
Will Torbald Posted November 19, 2015 Posted November 19, 2015 The exclusion principle requires something to not be two different things in the same sense. The properties of light as a particle or a wave are not the same sense, which was the difficult hump to get over. No one here is "catching this" because evidence of the properties of light is so easily replicated. It clearly does have the properties. To expand on this, it's also when something can't be itself and its opposite at the same time. Particles and waves are not opposite, just different. The opposite of a particle is its antimatter particle, not it's wave function.
Pelafina Posted November 19, 2015 Posted November 19, 2015 Particles and waves are not opposite, just different. The opposite of a particle is its antimatter particle, not it's wave function. And one thing can be two different things at the same time? This is illogical, therefore the scientists failed the first test of philosophy. Back to the drawing board for them.
Will Torbald Posted November 20, 2015 Posted November 20, 2015 And one thing can be two different things at the same time? This is illogical, therefore the scientists failed the first test of philosophy. Back to the drawing board for them. One thing can have two different properties at the same time. The particle function and the wave function are not mutually exclusive. An electron is always an electron, not an electron and a positron at the same time, which would apply to your logical argument, but not with the wave.
Pelafina Posted November 20, 2015 Posted November 20, 2015 In physics, an electro-magnetic wave is the oscillation of an electric field which induces a magnetic field. The magnetic field then induces an electric field and this repeats as the wave propagates at the speed of light in all directions. Light cannot be an EM field (which has no mass) and simultaneously a photon particle with mass, because this fails the test of logic. It's better philosophically to admit you don't know something, than to have an emotional attachment to the need to demonstrate complex knowledge and being wrong.
Carl Green Posted November 20, 2015 Posted November 20, 2015 I struggled through some of the original source paper. I *think* that the graphic shown above is the result of both electrons and photons, from differing sources, being 'shot' at a nanowire suspended on/by graphene and appearing in the same space. And the two results are transposed together based on the time axis. So, it's not necessarily 'single original' 'units' of light being split and imaged, but the two different things reacting to the same thing at the same time. Can anyone here 1] understand the source paper (not the phys.org one) and experiment, and 2] tell me if i'm even close here? Very much appreciated if so, thanks!
Will Torbald Posted November 20, 2015 Posted November 20, 2015 In physics, an electro-magnetic wave is the oscillation of an electric field which induces a magnetic field. The magnetic field then induces an electric field and this repeats as the wave propagates at the speed of light in all directions. Light cannot be an EM field (which has no mass) and simultaneously a photon particle with mass, because this fails the test of logic. It's better philosophically to admit you don't know something, than to have an emotional attachment to the need to demonstrate complex knowledge and being wrong. Einstein demonstrated that light is indeed a particle, a photon, more than a hundred years ago. It's what he got his Noble Price for. Refer to Quantum Electro Dynamics and Richard Feynman when talking about the current understanding of the physics of electricity and light. The only test science needs is the test of experiment, not of logic.
shirgall Posted November 20, 2015 Author Posted November 20, 2015 I struggled through some of the original source paper. I *think* that the graphic shown above is the result of both electrons and photons, from differing sources, being 'shot' at a nanowire suspended on/by graphene and appearing in the same space. And the two results are transposed together based on the time axis. So, it's not necessarily 'single original' 'units' of light being split and imaged, but the two different things reacting to the same thing at the same time. Carl, sorry I didn't acknowledge your posting earlier, I've been on the road this week. It is definitely a case of simultaneous observation from two different sensors, and using those observations to make the image. Calling the visualization a photograph might be a stretch, but they are bombarding it with electrons and photons. As it says in the original paper's abstract: "The resulting energy exchange between single electrons and the quanta of the photoinduced near-field is imaged synchronously with its spatial interference pattern." A lot of the physics here is over my head, though.
Pelafina Posted November 20, 2015 Posted November 20, 2015 Einstein demonstrated that light is indeed a particle, a photon, more than a hundred years ago. It's what he got his Noble Price for. Refer to Quantum Electro Dynamics and Richard Feynman when talking about the current understanding of the physics of electricity and light. The only test science needs is the test of experiment, not of logic. Philosophy is about (1) logic, and (2) evidence. There is no reason to do an experiment if the hypothesis is illogical. There is no reason to run a test to check if 1+1=5.
shirgall Posted November 20, 2015 Author Posted November 20, 2015 Philosophy is about (1) logic, and (2) evidence. There is no reason to do an experiment if the hypothesis is illogical. There is no reason to run a test to check if 1+1=5. When you make a prediction, you test it. When you see evidence to the contrary to a tenet, you modify the tenet. Even for "established" evidence, it is often instructive to try to see if you can observe something new (for example, when you design a more accurate instrument or testing procedure). Only superstition is immune to contrary evidence. And, by the way, philosophy is about truth, with an emphasis on the general and fundamental nature of reality, existence, knowledge, values, reason, mind, and language. (This part of Wikipedia's definition is decent enough to parrot here). Logic and evidence are components in the truth-seeking repertoire. It is not a hypothesis that light acts like a particle and a wave. It is already in evidence. What's being explored here is how they are different and how they are the same. These attributes are not opposite.
Pelafina Posted November 20, 2015 Posted November 20, 2015 It is not a hypothesis that light acts like a particle and a wave. It is already in evidence. What's being explored here is how they are different and how they are the same. These attributes are not opposite. Attributes are not opposite? A wave has zero mass. A photon has positive mass. How can light both have mass and not have mass?
Will Torbald Posted November 20, 2015 Posted November 20, 2015 Attributes are not opposite? A wave has zero mass. A photon has positive mass. How can light both have mass and not have mass? Photons don't have rest mass: http://www.askamathematician.com/2010/09/q-how-can-photons-have-energy-and-momentum-but-no-mass/ https://en.wikipedia.org/wiki/Photon#Experimental_checks_on_photon_mass Maybe you're confusing them with electrons, which do have mass.
Pelafina Posted November 23, 2015 Posted November 23, 2015 Photons don't have rest mass: http://www.askamathematician.com/2010/09/q-how-can-photons-have-energy-and-momentum-but-no-mass/ https://en.wikipedia.org/wiki/Photon#Experimental_checks_on_photon_mass Maybe you're confusing them with electrons, which do have mass. They have mass at rest but no mass when the move. This non-logical conclusion by scientists is being made because they are attempting to prove that they know what they are talking about, when in fact they are seriously confused about the nature of the universe.
Will Torbald Posted November 23, 2015 Posted November 23, 2015 They have mass at rest but no mass when the move. This non-logical conclusion by scientists is being made because they are attempting to prove that they know what they are talking about, when in fact they are seriously confused about the nature of the universe. Yes, but about you. You are the confused one.
shirgall Posted November 23, 2015 Author Posted November 23, 2015 They have mass at rest but no mass when the move. This non-logical conclusion by scientists is being made because they are attempting to prove that they know what they are talking about, when in fact they are seriously confused about the nature of the universe. Did you forget that mass and energy can be converted into one another? When photons strike matter despite being massless in flight their energy is converted to kinetic energy that dislodges and frees electrons from their position. This photoelectric effect makes solar panels work allows plant life to make sugars from sunlight. https://bama.ua.edu/~hsmithso/class/Web/Photoelectric-effect.pdf
Pelafina Posted November 23, 2015 Posted November 23, 2015 Did you forget that mass and energy can be converted into one another? When photons strike matter despite being massless in flight their energy is converted to kinetic energy that dislodges and frees electrons from their position. This photoelectric effect makes solar panels work allows plant life to make sugars from sunlight. https://bama.ua.edu/~hsmithso/class/Web/Photoelectric-effect.pdf Scientists say that photons have rest mass, but no mass when they are on the move. They have more kinetic energy when moving, which means they must have more mass when moving not zero mass when moving. Why does the (relativistic) mass of an object increase when its speed approaches that of light?http://physics.stackexchange.com/questions/1686/why-does-the-relativistic-mass-of-an-object-increase-when-its-speed-approaches
Will Torbald Posted November 23, 2015 Posted November 23, 2015 Scientists say that photons have rest mass, but no mass when they are on the move. They have more kinetic energy when moving, which means they must have more mass when moving not zero mass when moving. Why does the (relativistic) mass of an object increase when its speed approaches that of light?http://physics.stackexchange.com/questions/1686/why-does-the-relativistic-mass-of-an-object-increase-when-its-speed-approaches It's the opposite. Photons don't have rest mass. The whole point of special relativity is that light speed is absolute because it has no rest mass. Any object with rest mass trying to reach the speed of light would need infinite energy to do it.
Carl Green Posted November 23, 2015 Posted November 23, 2015 Another general physics question. Would it be considered more accurate to call The Speed of Light, the Universal Speed Limit? I think calling what that actually represents in reality as "the speed of light" is yet another misleading popular term.
Will Torbald Posted November 23, 2015 Posted November 23, 2015 Another general physics question. Would it be considered more accurate to call The Speed of Light, the Universal Speed Limit? I think calling what that actually represents in reality as "the speed of light" is yet another misleading popular term. Yes, that is a great way to call it, and I actually think I've heard it said before in explanations of light and relativity. Photons aren't the only particles that travel at th speed of light. All massless particles of the standard model travel at that speed, like gluons and W and Z bosons.
Guest Gee Posted November 24, 2015 Posted November 24, 2015 A photograph is just an image crated by light falling upon a light sensitive surface. The information used to create the pictorial representation was captured using a post-column Gatan Quantum GIF electron energy loss spectrometer. The important part here is spectrometer. You can turn a good digital camera into a spectrometer by fitting it with a diffraction grating. (even smart phone camera http://www.wired.co.uk/news/archive/2010-10/11/camera-phone-spectrometer ). So a spectrometer is essentially a digital camera with a diffraction grating, which would make this a really cool picture.
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