I think you can use somehthing similar to eletron emission gun used in electron microscopes. In eletron microscope, a fluorescent plate is used to visualize the electron beam. Works quite well.
Satoru
All the more reason to fill the bus full of spammers and try the experiment.
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I've heard that even machine gun bullets diffract.
Cheers! Rich
I don't believe in "photons", rather I look at a "photon" as a predictable electromagnetic emission from matter. Just like a submarine can tell a ship by its propeller noise, matter also emits characteristic electromagnetic energy (ie. due to the quantized electron orbitals), but to go from that to saying all electromagnetic energy is quantized seems to be illogical.
A magnetic field is completely non quantized, and its strength decreases continuously as you move away from the magnet. How can this field be made of quantized photons (virtual photons they say!) if it has a continuously varying intensity over distance? I think the only way is to assume space and distance itself is also quantized which seems even more unlikely than the concept of a photon.
Planck's constant, 6.626 * 10^-34 Joule*seconds, is that the energy that is released by the electron dropping an orbital in the hydrogen atom?
If Planck's constant describes this or something similar, then also it should be looked at that this is a variable amount of energy depending on the external continuous electric or magnetic field that the hydrogen atom is immersed in, ie. the Stark and Zeeman effects. So if that is the case Planck's constant is only a theoretical quantization of an isolated atom, which doesn't exist in reality, ie. there is the cosmic microwave background radiation everywhere, which will shift the amount of energy released by an electron that jumps an orbital.
cheers, Jamie
it
r ?You can run any of the Youngs slit experiments at a flux rate where there is only one particle in the apparatus at any one time and still get interference fringes. You can even run it with protons, neutrons, silver atoms or buckeyballs (I think that is the largest mass particle that has been tried to date).
And the fun bit is that even when there is only one particle at a time it still generates the interference pattern it just takes longer to develop. ISTR it was done live at one of the UK Royal Institution Xmas childrens lectures a few years back.
Alan Boksenberg developed a pre-CCD era astronomical Image Photon Counting System that relied on converting rare photons from a high dispersion astronomical spectrograph into electrons, accelerating them and measuring the centroid of the resulting photon splash on a phosphor. It was a highly successful technique in its day. Much more sensitive than anything else available at the time. See for example:
You are going to have a very hard time explaining the photoelectric effect then (and also avoiding the UV catastrophe for that matter). Einstein got the 1921 Nobel prize in part for his work on quantum theory published in 1905.
It isn't continuously varying. You can measure the ultimate quantum step of magnetisation with a Josephson junction SQUID. eg,
They are equisitely sensitive magnetic field detectors. Measuring flux quantisation in a SQUID was an optional third year physics practical experiment at my university.
Space itself could also be quantised or foamlike at least on the scale of the Plank length. However, that is so tiny that apart from in the earliest stages of the Big Bang it is to all intents and purposes continuous.
You are probably not going to like virtual photons then. See for example the Casimir effect.
Regards, Martin Brown
Evidence, please. Cite the experiment that measured a change in magnetic flux that is a small fraction of 10 to the minus
15 Webers (the size of the quantum fluxoid) with a change of distance that is a small fraction of 10 to the minus 35 meters (the Plank length).I would be interested in how you calculate the likelyhood of something being quantitized vs. non-quantized. Do you have any basis for deciding which is more likely other than gut feeling?
-- Guy Macon
The photoelectric effect is just proof that matters energy states are quantized, as it requires stepped frequencies of electromagnetic energy to trigger it to release electrons. It doesn't mean that the electromagnetic energy itself is quantized. The UV catastrophe:
is what happens when you don't acknowledge that matters energy states are quantized.
From reading about these, they are formed from two Josephson junctions, and those output a varying quantized frequency proportional to the field being sensed. This doesn't necessarily mean that the field itself is quantized, it may be that the instrument, ie. the tunneling of the cooper pairs through the junction, is quantized.
From reading about cooper pairs on this site:
"This pairing results from a slight attraction between the electrons related to lattice vibrations; the coupling to the lattice is called a phonon interaction."
So these cooper pairs are governed by the "phonon interaction" and phonons:
are quantized vibrations in matter (all vibration in matter is quantized?). So it seems that the measured field may in fact be continuously varying. Is there any way to measure a field with matter where you won't see quantization? I think normal electron flow in matter is not governed by quantization, and therefore a simple antenna should output a continuous signal in the presence of a continuous field, whether this is theorectically possible to measure below the quantization level of a Josephson junction SQUID is another matter.
The Casimir effect is thought to occur from:
Any continuous system can be quantized if desired, it is just a model that some people like thinking in terms of, I personally don't understand why someone would want to quantize every thing possible under the stars, but I guess it is a model that can describe reality in a unique way, even if it is complete nonsense.
cheers, Jamie
The fact that we are able to discuss whether something is quantized or not continuously is pretty good evidence for me ;)
cheers, Jamie
>
That's no evidence at all! Is the fact that we are able to discuss whether a song coming out of a speaker is quantitized (on a CD) vs. non-quantized (on a vinyl record) evidence that CDs don't exist?
-- Guy Macon
There is nothing logical about quantum mechanics. But that's how someone built this universe, and we're stuck with it.
What you see as intensity dropping off smoothly with distance is merely the statistics of large numbers.
No. The engineering units are wrong for this to be an energy. Look it up.
Take some physics courses and untangle this stuff. The universe is nothing like what you imagine it to be, but it is a lot of fun.
John
Feynman once said "all of quantum mechanics is contained in the two slit experiment, unfortunately no one understands the two slit experiment."
-- These are my opinions, not necessarily my employer\'s. I hate spam.
I'm not saying its impossible that electromagnetic energy is quantized, I just prefer to view it as a continuous field, instead of take on the abstract concepts of quantum mechanics like "measurement collapses the wave function", I don't believe in the wave function, I believe in an actual wave, that is not possible to collapse, only is able to be partially absorbed by matter, with a corresponding vibrational states change in the matter.
Quantum mechanics should only be applied to systems with proven discrete state changes, ie. matter. I don't understand why it was applied to light, as I don't think it is possible to prove that light is quantized or not, only that matter interacts with light in certain quantities. Light was basically erased by quantum mechanics into probability waves, seems like a human idea rather than reality to me.
Also possibly gravity is an electromagnetic force (of unmeasured high frequency) that pushes matter together, like the Casimir effect.
To go a step beyond physics to philosophy, maybe the only way to acknowledge the continuous nature of light and the universe is to experience it "spiritually". That is what Schroedinger did, who called himself a Vedantist (Hindu philosopher):
who extended the classical wave equations to matters quantized vibrations, he had to be convinced by Bohr to go along with quantum mechanics, and in his later life he lectured from a wave based perspective only:
"Schrödinger disliked the generally accepted dual description in terms of waves and particles, with a statistical interpretation for the waves, and tried to set up a theory in terms of waves only. This led him into controversy with other leading physicists."
Also "Schrödinger's cat" was a thought experiment by Schrödinger to show the ridiculous nature of quantum mechanics:
The whole idea of observation and measurement is the problem in quantum mechanics. Observation and measurement is merely the absorption of electromagnetic energy by matter, nothing more, and there is no "wave function" collapse associated with this absorption. That strange concept only comes when you assume light is quantized and doesn't actually exist except as a transaction token between matter.
cheers, Jamie
He had some good lines.
Some other famous guy, I can't remember who, said that if quantum mechanics doesn't frighten you, you haven't studied it enough.
I've always thought that the beam-splitter interferometer was frightening. It's like those photons were being deliberately malicious.
John
When a photon hits a good half-silvered mirror, all of it is either is reflected or all of it passes through. A pair of photon-counting detectors will demonstrate this. But if you remove the detectors, it does both... it splits and the pieces can be made to interfere with themselves, even after traveling enormous distances. But you can never detect one of the split pieces as being anything but the original photon, and you can never detect them both.
Photons are demonstrably local and indivisible, and travel at the speed of light, so can't possibly interfere with themselves over long paths. But they do.
Explain that with classical wave theory!
John
I wish you had explained at the beginning that your opinions about quantum theory are preferences based on philosophy and spirituality. Instead you wrote "A magnetic field is completely non quantized" -- an unqualified and absolute claim about the observable universe.
There are more things in heaven and earth, Jamie, than are dreamt of in your philosophy.
-- Guy Macon
Some of them are. >:->
Cheers! Rich
-- For more information, please feel free to visit http://www.godchannel.com
For this experiment from a wave perspective of light, you emit a characteristic frequency and energy of electromagnetic energy, and this wave, of fixed frequency, hits and passes through the silvered mirror at the same time, every time. It will interfere with itself when rejoined any time in the future, constructively or destructively based on the path length of the split beams. I think this can explain most interferometer setups, but I couldn't find an example of the exact experiment you describe.
From this page:
If you assume that light is quantized as photons, then try to understand an interferometer in those terms, that is when things become paradoxical and confusing (non locality / spooky action at a distance), isn't that a good hint that maybe the initial assumption of light being quantized is incorrect? :)
I like to try to analyze all these setups from a wave perspective and avoid acknowledging the possibility of particles, seems to keep things more simple, maybe incorrect too, but simple is nice ;)
cheers, Jamie
No. It's an indication that your expectations are incorrect. It does what it does.
Fine, believe what you like, but don't experiment with a beam splitter and two photon detectors.
John
Hi,
Do you have a link to the experiment setup that you were describing with the photon detectors? I would like to take a look at it closer but didnt see the exact setup.
Regarding entanglement where the two measured particles have opposite spins, I would think that when the two particles are created they get their opposite spins at that point.
cheers, Jamie
No specific reference. You'll have to hunt. The page you just cited says pretty much the same thing.
What's amazing is that they got opposite spins at creation, but the spin axis is totally undefined. The spin of particle X is undefined and the spin of particle Y is undefined, but they are strictly opposite. So, after they are a light-year apart, if someone measures the up-down spin of X and discovers that X is up, then the spin of Y is down. But if you consider spin to be a left-right thing and measure one as left, then instantly the other becomes right. The particles have no idea of your definition of spin until the instant you do the test, except that they know that spin is quantized, +1 or -1 along
*any* axis you pick, and they know that their spin is the opposite of their mate's.I know people, some who have posted here, that think that consciousness does not exist. They say that the brain is just a mechanism that follows physical laws, just a state machine. The fact that randomness is involved just makes it a flakey state machine. If you cling to classical physics, then that's a perfectly reasonable viewpoint. We're just a bag of chemicals.
But in fact the brain is a quantum-mechanical computer, and quantum mechanics is mystical. Things happen in concert, light-years apart. A photon is indivisible, but knows that there is a slit far away, and acts accordingly. A photon can interfere with itself over a path that's miles long, a path that it provably does not take. Matter is solid and is a wave; it's mostly here but a little bit everywhere. To cling to classical physics is to deny magic and, I think, to deny spirituality and consciousness itself.
How's that on the rant-o-meter?
John
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