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I have a thing going on with the whereabouts of electrons in atoms, so when I read something surprising like this, I chase it hoping to get a little more insight into the subject. "Both single electrons now become paired and share the overlapping energy levels i.e. they can now also move in the energy level of the electron from the other atom so they can now move around each nuclei. However, most of the time they are found in the region between both nuclei as they are attracted by both nuclei."
They are talking for almost specific (?) electrons being at specific region around the atom. Where such finding are coming from. Are these theoretical or experimental findings. Pump-probe spectroscopy, photoelectron spectroscopy and crystallography, is all I only know to find electron energies and densities, but not positions as accurate to say that specific electrons "are found in the region between both nuclei"
Through which methods and what measurements they find that electrons are moving around each nuclei.
Would you know what to read to appreciate in its full extent the experimental procedures that lead to such findings/conclusions.
I'm confident it's really a standing-wave thing. See atomic orbitals on Wikipedia and note this: "The electrons do not orbit the nucleus in the manner of a planet orbiting the sun, but instead exist as standing waves". Also take a look at What is an Electron? by Frank Wilczek and note this: "the proper quantum mechanical description of electrons involves wave functions, whose oscillation patterns are standing waves”.fay's unKle wrote:Maybe the standing wave thing is one of the two ways of characterizing the electron, particle or wave ?
No. The electron goes through both slits. However IMHO detection involves something akin to the optical Fourier transform. See Steven Lehar's web page:fay's unKle wrote:It fits to abstract discriptions of physical observations, gives them more substantial identity. In the two slit experiment they say that electrons go through both openings at the same time. Am I mistaken?
If you take an interest in this stuff you will become a scientist, and then whilst you never stop learning, you will ending up learning more than some.fay's unKle wrote:I think the non scientist will always remain a "student" of the subject.
It's a non-sequitur. See Wikipedia where you can read that “observation of a single electron in a Penning trap shows the upper limit of the particle's radius is 10−22 meters”. But when you follow up on the references and read Hans Dehmelt’s 1989 Nobel lecture you appreciate that the upper limit is merely an extrapolation. It’s an extrapolation from a measured g value, which relies upon "a plausible relation given by Brodsky and Drell (1980) for the simplest composite theoretical model of the electron". The extrapolation yields an electron radius R ≈ 10^-20 cm, but it isn't a measurement. Especially when "the electron forms a 1 μm long wave packet, 30 nm in diameter". When you follow the trail back to Brodsky and Dell you can read the anomalous magnetic moment and limits on fermion substructure. And what you read is this: "If the electron or muon is in fact a composite system, it is very different from the familiar picture of a bound state formed of elementary constituents since it must be simultaneously light in mass and small in spatial extension". The conclusion is that if an electron is composite it must be small. But there's no actual evidence that it’s composite. So it’s a non-sequitur to claim that the electron must be small.fay's unKle wrote:But I have seen somewhere an estimate of its size 10*"(-18) (I wish I could find it to refere to it in quotations) and I tend to see it as a particle because that's what I understand.
John Duffield : I'm confident it's really a standing-wave thing. See atomic orbitals on Wikipedia and note this: "The electrons do not orbit the nucleus in the manner of a planet orbiting the sun, but instead exist as standing waves". Also take a look at What is an Electron? by Frank Wilczek and note this: "the proper quantum mechanical description of electrons involves wave functions, whose oscillation patterns are standing waves”.
John Duffield : No. The electron goes through both slits. However IMHO detection involves something akin to the optical Fourier transform. See Steven Lehar's web page:
John Duffield: It's a non-sequitur. See Wikipedia where you can read that “observation of a single electron in a Penning trap shows the upper limit of the particle's radius is 10−22 meters”.
I'm confident it's really a standing-wave thing. See atomic orbitals on Wikipedia and note this: "The electrons do not orbit the nucleus in the manner of a planet orbiting the sun, but instead exist as standing waves". Also take a look at What is an Electron? by Frank Wilczek and note this: "the proper quantum mechanical description of electrons involves wave functions, whose oscillation patterns are standing waves”.
"If we actually knew how electrons are distributed and move in atoms we would have been able to know better how they bond to form compounds and find new improved materials without having to test hundreds (or even thousands) of combinations every day in labs around the world" OR ".....we have to understand how atoms combine to form molecules; how electrons and nuclei couple........How do all these things behave in a correlated way, ‘dynamically’ in time and space, both at the electron and atomic levels?” AND "Physicists have long chased an elusive goal: the ability to "freeze" and then study the motion of electrons in matter. Such experiments could help confirm theories of electron motion and yield insights into how and why chemical reactions take place."
instantaneously (instantaneous dipole): for instance, all 34 (2 x 17) the electrons in a chlorine molecule are in permanent motion and at a particular instant they may not be evenly distributed over the two atoms making
As if this dual behavior is not confusing enough, trying to detect the electron as it passes through the slits changes the entire outcome of the experiment. The electron is never detected simultaneously in both slits; instead, a detector will find it passes through only one opening. But when this detector is in place and making this measurement, the interference pattern disappears. We are left instead with the leftmost pattern on the screen above which was predicted if electrons are particles going through one opening or another: two bright spots in front of the each individual slits. Our measurement at the openings has forced the electron to behave like a classical particle.
..... he invites (Feynman) the reader to imagine firing individual electrons through two slits and then marking the position where each electron strikes a screen behind the slits. After many electrons have passed through the slits, the marks on the screen will comprise a diffraction pattern – illustrating the wave-like behaviour of each electron. But if one were to cover up one of the slits so that each electron could only pass through the other slit, the diffraction pattern would not appear – showing that each electron does indeed travel through both slits.....The first single-electron experiment to use an actual double slit was reported in 2008 by Pozzi and colleagues. The Italian team also conducted the experiment with one slit plugged, which – as expected – did not lead to the creation of a double-slit diffraction pattern. The team also performed another experiment in 2012, in which the arrivals of individual electrons from a double slit were recorded one at a time.
Electron movement can be explored in the attosecond dimension using laser-generated ultrashort light pulses. In their project MEGAS (megaherz attosecond pulses for ultrafast photoelectron microscopy and spectroscopy), scientists from the Max Planck Institute of Quantum Optics, Ludwig Maximilians University and the Fraunhofer Institute in Jena and Aachen are developing a new source of such laser pulses. The researchers are building a short-pulse laser that can produce attosecond-long light pulses at a rate of tens of millions of times per second. With this, electron motion can be recorded, or “photographed”, in the dimensions of both space and time. Until now, attosecond pulses could only be produced at a much lower repetition rate, allowing electron movement to be recorded in space or in time – but not both simultaneously.
fay's unKle: "by whatever means, an electron can be isolated in its orbit for the brief interval needed to form an image. Needless to say it should not be possible to 'image' a wave." but instead of the word orbit I would use position. Do you think that advances like this will aid at all, are we at the same wave length ? (not wave function, please) "A zeptosecond stopwatch for the microcosm. For the first time ever, physicists from Ludwig-Maximilians-Universität Munich, the Technische Universität München and the Max Planck Institute of Quantum Optics have recorded an internal atomic event with an accuracy of a trillionth of a billionth of a second"
fay's unKle : FOR NOW, BECAUSE SOME OF US IN THEIR OWN WAY WILL BE PURSUING THE ENDLESS SUBJECTS, FOR A LIFE'S TIME, OF THE WHEREABOUTS OF ELECTRONS, BONDING,NEURONS AND BIOLOGICAL SELF-ASSEMBLY. THEY ARE THE SALT AND PEPPER IN SCIENCE AND TECHNOLOGY TO ME, MIND REFRESHING AND STIMULANT AND SOME TIMES CAN BE QUITE INTELLECTUALLY CHALLENGING, FOR AS LONG AS ONE DOESN'T LIVE ONLY WITH THEM.
"What if sub-atomic particles were particles and had nothing at all to do with waves?"
The reason I put this question is that why on earth should the electron undergo so many interactions and gauge interactions if not to preserve its identity. This is something that a wave would not have to do and would not be able to do because by its very nature a wave's energy is not localised. Hence a wave cannot undergo either interactions or gauge interactions in the way that is applied to electrons.
They are talking for almost specific (?) electrons being at specific region around the atom. Where such finding are coming from.
But I take the kick out of "Real-time observation of valence electron motion" and "Electron Caught On Film For The First Time" or "For the first time ever, scientists watch an atom's electrons moving in real time" and read them. Can't see though all that the title promises, maybe because I'm not a scientist to have all the necessary knowledgeable background or I see everything from an engineering perspective and expect more concrete observations.
Post by fay's unKle » Sun Mar 12, 2017 5:55 pm
I stopped reading quantum mechanics and about bosons and up and down and charm quarks and their color long time ago so I will never get close to some of the stuff you are reffering too, except if quantum computers will become reality, then to understand how they function one must have a really deep understanding. (and for entanglement, if secure information transfer will been done through it)
Hold on, it is a little more complicated than I at first thought. A sends a sequence of signals to B randomly polarised. B uses a random sequence of filters to read the message. Then B sends his sequence to A and A sends his sequence to B, Then the key can be worked out. This is possible because if a horizontallly polarised photon passes through a diagonal spliiter it will show up at only one photon detector. Apparently this form of encryption has been broken. Could you elucidate a bit more.
??? This last one i tried to understand but i only guessed a little what you want to say.I would like to ask you where exactly is quantum encryption? I know that there is encryption in the sense of sending message coded in qubits does not at the moment exist, which is what true quantum encryption is supposed to do, right?
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