How does a radio antenna work quantum mechanically?
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From: Darwin123 on 2 Aug 2010 17:04 On Aug 2, 1:50 pm, Excognito <stuartbr...(a)gmail.com> wrote: > On Aug 1, 3:43 pm, Darwin123 <drosen0...(a)yahoo.com> wrote: > > > > > On Jul 31, 5:52 pm, Excognito <stuartbr...(a)gmail.com> wrote: > > > > On 31 July, 20:01, Darwin123 <drosen0...(a)yahoo.com> wrote: > > > > > On Jul 30, 8:00 pm, Marvin the Martian <mar...(a)ontomars.org> wrote:> On Thu, 29 Jul 2010 14:42:35 -0700, Excognito wrote: > Another is, > perhaps, your use of the word 'collide' - I'm slowly forming the > impression that 'absorption' is perhaps a better working concept for > me (partly to make the point that the photon no longer exists, or at > least in the form it did). When I wrote the word "collide," I was thinking about how those interactions appear when described in Feynmann diagrams. The Feynmann diagrams show the photon moving to an electric charge. Then the electric charge changes its state. The photon has disappeared. A photon that reappears later in the electrons history is clearly a "new photon." The photon is sometime shown disappearing when it touches the electric charge. However, sometimes the photon seems to change direction with no intermediate time of vanishing. I interpret this as the photon being absorbed, and a new one immediately emitted. I like the second interpretation as I can't see a photon changing during its travels. A photon travels at the speed of light. Therefore, time has stopped in its rest frame. Therefore, a photon should not actually change. Feynmann diagrams are used a trick in the mathematics of QED. Some scientists refer to think that the Feynmann diagrams do not describe physics, but are just a "book keeping" method. Perturbation methods often involve complicated counting methods that require strange diagrams. Feynmann diagrams can be considered "bookkeeping." However, this is a point of semantics or philosophy. You don't seem to be totally concerned with the issue of what is "real" so much as to how classical and quantum mechanics correspond. A virtual photon is at least as "real" as an electric field, or a magnetic field. If you look closely, the classical concept of "field" appears rather blurry. I think you are coming to the same conclusion that I came to. The present understanding of QED has more to do with Faraday's Laws than to Newton's Laws. When Faraday first introduced his concept of "field," it bothered physicists. Faraday couldn't do mathematical physics as described by Principia. He couldn't work with mathematical symbols. There may have been a learning disability involved. So he relied heavily on diagramic methods to solve problems. When scientists asked him to analyze his experiments mathematically, he would get in a huff. He would say that experimental physics should not depend on mathematics. Of course, Maxwell had something to say about that. He took Faradays Laws, added one extra law, wrote down the laws with calculus and the rest is history. The following is my hypothesis. I think the problem is this. Faraday's Laws logically contradict the laws of mechanics as presented in Principia. You can't use Faraday's Laws without logically contradicting something in Principia. Einsteinian relativity is a way of resolving Principia with Faraday's Laws. The corresponding problem in quantum mechanics is this. Quantum mechanics has led to the idea that light is also made of photons. However, there is a contradiction between the behavior of photons and Principia. The properties of photons are not completely described by Principia. In the same way Faraday's laws contradict Principia, the behavior of photons contradicts Principia. So quantum electrodynamics is a way of resolving this discrepancy between the behavior of photons and Principia. I some people, even some scientists, are having trouble fully recognizing this. If anyone would allow me to teach a course in Modern Physics, I would start with this hypothesis. Principia and classical electrodynamics just don't get along. At least not completely. Both theories work for a wide range of conditions. There is an overlap. Under some conditions, both classical electrodynamics and Principia work to a high degree of precision. However, technology late in the nineteenth century drifted into "realms" where the discrepancy was noticeable. Independent of who invented what, the development of modern physics started with the contradiction. If one understands this, the odd development of modern physics becomes more understandable. > > Side question: Is there anything in theory (or practice) that gives an > estimate for how long it takes to make the transition from the states > 'electron and photon' to the state '(more energetic) electron'? Its called the Heisenbergy Uncertainty Principle. A virtual photon is a photon under conditions where the uncertainty in energy is greater than the most probable energy of the photon. The uncertainty in time can thus be estimated as Planck's constant divided by the uncertainty in energy. Basically, this corresponds to an uncertainty law in classical physics. When an electronics engineer wants to estimate the response time of his system, he often measures the frequency bandwidth of his system. The response time is the inverse of the bandwidth. This is perfectly classical. A QEDer could say that the bandwidth tells you the transition time of states that are changed by virtual photons.
From: Darwin123 on 2 Aug 2010 19:18 On Aug 2, 5:01 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > news:222c4fd5-9424-4b34-a8b8-658c9e5fe776(a)m17g2000prl.googlegroups.com... > On Aug 1, 10:34 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > > > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > So what is your problem with a photon being a single cycle of a wave > > 1) A "single cycle" of a wave can have a large amount of energy. > Real photons are caused by the quantization of the waves amplitude, > not the waves wavelength. > ==================================== > Three cycles would have three times as much energy. > Fifty-five cycles would have fifty-five times as much energy. > What is your problem with a photon being a single cycle of a wave, drosen? Because the energy of a "cycle" of the radio waves increases with amplitude, not frequency. Let the frequency of a radio wave be 1 Hz. One cycle of radio energy can have 1 J of energy. Once cycle of radio energy can have 10^-31 J of energy. One cycle of radio energy can have 10^31 J of energy. One cycle of the radio wave can have a most probable value of 6.626x10^-34 J. One cycle of the radio wave can have a most probable value of 6.626x10^-34 J. The energy of the "cycle" is the proportional to the square of the amplitude of the wave. The exact proportionality constant depends on the geometry of the box that contains the circle. A "Newtonian" particle has to have a fixed amount of kinetic energy that depends only on the velocity of the particle. Your definition of photon as "a cycle of energy" contradicts your claim that the photon is a "Newtonian" particle. The photon, which is a quantum of energy, has an energy fixed by the frequency of the wave. Your "cycle" can have any value for energy. One cycle can contain 1 photon, 10^35 photons, or any amount of energy. You have amplitude and wavelength mixed up. The photon is related to quantization of amplitude, not quantization of frequency. Consider a radio wave with a frequency of 1 Hz. One photon of such energy contains 6.626x10^-34 J. With an uncertainty determined by the Heisenberg uncertainty condition. > > 2) Single "cycles" of the wave have an uncertainty in position > determined by the wavelength of the cycle. A radio wave can have a > wavelength that is miles long. > ==================================== > It all arrives, like a carriage on a railway train. The carriage can't fit. The contents can't arrive all at the same time. The photoelectric effect is almost instantaneous, occurring within the bandwidth of the process. How does a photon, miles wide, manage to deposit all its energy into one teeny atom, out of all the atoms in the sample, in such a short time? The single cycle extends of millions of atoms. Consider that radio wave of 1 Hz. It has a wavelength of 3x10^8 m. We chose a cavity and an amplitude so the radio wave has only one photon. It has energy enough for one photon. It is incident on a gas with an absorption band at 1 Hz. The atoms in this gas are 10^-9 m in diameter. An absorption takes place at some point, instantly, at one ion only. The other ions are unaffected. How did the photon, which is 3x10^8 m wide, end up packing all the energy into an atom 10^-9 m wide? This what happens to > railway trains. <shrug> > > A single atom, maybe a nanometer wide, > can absorb a quantum of energy from a radi wave. That is what happens > in atomic clocks. > ===================================== > A single platform, maybe a carriage door wide, can absorb a > quantum of passengers from a railway train. That is what happens > in cities. > A single tray, maybe a Mars bar wide, can absorb a quantum of candy > when you put a quantum coin in the slot. That is what happens in > vending machines. What? I absolutely don't understand this example. > What is your problem with a photon being a single cycle of a wave, drosen? > > 3) A single cycle of a wave has an uncertainty in frequency. If you > chop a single cycle out of a wave, it becomes a wave packet. > > ================================================= > And wave packets are not called photons? No! Wave packets are not called photons! > > The > frequency of this chopped out cycle has a bandwidth determined by the > classical uncertainty principle. > ================================================= > Quantum passengers leave the carriage door and wander off in > different directions into the city. Tell us what the classical uncertainty > principle is, drosen. Uncertainty in frequency times uncertainty in time is greater than or equal to 1. It is used all the time by electrical engineers. > > The bandwidth of a single cycle of a > wave can be quite large. However, a real photon can exchange a fixed > amount of energy. > > ================================================= > A real radio wave can exchange a fixed amount of energy. > A real railway train with real seats can exchange a fixed amount of > passengers, some tall, some short. What? I don't see what the analogy is. How is the height of a person analogous to the wavelength of a "cycle?" > > and what do your "virtual" photons do? Create "virtual" radio waves? > > Photons, both real and virtual, > ================================================= > Tell us what a virtual photon is, drosen. A quantized expression of a near electromagnetiic field. > > change the energy and momentum of > electrons they interact with. A virtual photon is annihilated or > created when it collides with an electron in the wire or antennae. > A virtual photon can "create" real photons. A virtual photon can > collide with an electron and be annihilated, passing changing the > energy of the electron. The electron can emit a real photon. > ==================================== > Three photons would hit three electrons. What? This is totally stupid! > What is your problem with a photon being a single cycle of a wave, drosen? The properties of a single cycle don't in any way, shape or form match the properties of photons. Good bye!
From: Androcles on 2 Aug 2010 20:36 "Darwin123" <drosen0000(a)yahoo.com> wrote in message news:791e4a6f-a858-484d-90a2-13e9309c3749(a)i24g2000yqa.googlegroups.com... On Aug 2, 5:01 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > news:222c4fd5-9424-4b34-a8b8-658c9e5fe776(a)m17g2000prl.googlegroups.com... > On Aug 1, 10:34 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > > > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > So what is your problem with a photon being a single cycle of a wave > > 1) A "single cycle" of a wave can have a large amount of energy. > Real photons are caused by the quantization of the waves amplitude, > not the waves wavelength. > ==================================== > Three cycles would have three times as much energy. > Fifty-five cycles would have fifty-five times as much energy. > What is your problem with a photon being a single cycle of a wave, drosen? Because the energy of a "cycle" of the radio waves increases with amplitude, not frequency. ================================================ Ok, now we may be making progress. Let the frequency of a radio wave be 1 Hz. One cycle of radio energy can have 1 J of energy. ================================================= Ok, so why isn't that called a photon? drosen will answer "Because it has more amplitude than a photon". Next question: what is the amplitude of a photon? Once cycle of radio energy can have 10^-31 J of energy. One cycle of radio energy can have 10^31 J of energy. One cycle of the radio wave can have a most probable value =========================================== Sorry, I'm not doing probable today. We'll get to probable later. Q: Why can't a great big atom emit high amplitude photons? A: Because there are no great big atoms. Q: Can lots of normal atoms emit 1J of energy? A: Of course. Light bulbs and lasers do it all the time. Q: If we could somehow arrange for an atom to emit one photon at a time, one after the other, until 1 J of energy has been sent, isn't that a COHERENT light wave? http://www.merriam-webster.com/dictionary/coherent Date: circa 1555 1 a : logically or aesthetically ordered or integrated : consistent <coherent style> <a coherent argument> b : having clarity or intelligibility : understandable <a coherent person> <a coherent passage> 3 a : relating to or composed of waves having a constant difference in phase <coherent light> b : producing coherent light <a coherent source> Please be coherent, drosen. If we double the rate of photon emission we can send 1 J of energy in half the time, thereby doubling the POWER. What is your problem with a radio wave being composed of single photons, one after the other so that they all have a constant difference in phase, even if they are big fat photons with lots of amplitude?
From: Darwin123 on 2 Aug 2010 22:27 On Aug 2, 8:36 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > news:791e4a6f-a858-484d-90a2-13e9309c3749(a)i24g2000yqa.googlegroups.com... > On Aug 2, 5:01 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote:> "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > >news:222c4fd5-9424-4b34-a8b8-658c9e5fe776(a)m17g2000prl.googlegroups.com.... > > On Aug 1, 10:34 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > > > > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > > So what is your problem with a photon being a single cycle of a wave > > > 1) A "single cycle" of a wave can have a large amount of energy. > > Real photons are caused by the quantization of the waves amplitude, > > not the waves wavelength. > > ==================================== > > Three cycles would have three times as much energy. > > Fifty-five cycles would have fifty-five times as much energy. > > What is your problem with a photon being a single cycle of a wave, drosen? > > Because the energy of a "cycle" of the radio waves increases with > amplitude, not frequency. > ================================================ > Ok, now we may be making progress. > > Let the frequency of a radio wave be 1 Hz. > One cycle of radio energy can have 1 J of energy. > ================================================= > Ok, so why isn't that called a photon? > drosen will answer "Because it has more amplitude than a photon". > Next question: what is the amplitude of a photon? > > Once cycle of radio energy can have 10^-31 J of energy. > One cycle of radio energy can have 10^31 J of energy. > One cycle of the radio wave can have a most probable value > =========================================== > Sorry, I'm not doing probable today. We'll get to probable later. > > Q: Why can't a great big atom emit high amplitude photons? There is no such thing as "high amplitude photon". One photon corresponds to a fix amplitude. An atom emits a small amount of energy, losing a small amount of amplitude, corresponding to one photon. Your high amplitude photon is a contradiction in terms. The atom emits a photon as a unit. It does not emit "single wave cycles". Since you don't like me to give links, I will merely mention one counter example to your model. Femtosecond lasers provide light pulses that are very short. Most femtosecond lasers make pulses only a few cycles long. Some femtosecond lasers can make single cycle pulses. The amplitude of the wave packet can be decreased by neutral density filters. The amplitude of the wave packet can be continuously increased by amplifiers. The energy of the cycles is not distributed as a unit. There are high amplitude cycles. There are femtosecond lasers that emit on cycle of light. The one cycle of light is a very short wave packet. This wave packet can contain a lot of energy. This "single cycle" of light contains billions of photons. There is no fixed energy corresponding to a wave packet. The energy of the wave packet is not absorbed or emitted as one unit. Although the femtosecond laser emits these short wave packets, the wave packet itself has to develop with time as it bounces back and forth in the cavity. This is not an issue of theory. This is experiment. Single cycles contain varying amounts of energy. A high amplitude cycle would contain a lot of energy. Atoms emit a fixed amount of energy, which is defined as the quantum of energy. Thus, the amplitude of the cycle Experimental measurements show it doesn't. The amount of energy emitted by an atom is fixed. > A: Because there are no great big atoms. > Q: Can lots of normal atoms emit 1J of energy? Yes, of course. However, each atom absorbs or emits a single photon. You can add up a lot of photons to make a high amplitude pulse. Even a high amplitude pulse with one cycle. The lasing medium in femtosecond lasers has lots of atoms. It manages to make a short pulse with high amplitude. > A: Of course. Light bulbs and lasers do it all the time. > Q: If we could somehow arrange for an atom to emit one photon at >a time, one after the other, until 1 J of energy has been sent, > isn't that a COHERENT light wave? No. That does not describe a coherent light wave. The photons in a coherent light wave are Poisson distributed. Their emission is random, although with a well defined probability. The arrival times, and the emission times, of a coherent light wave is not periodic or determined. Many investigators have examined the emission times of coherent light sources. Experiment has clearly shown that coherent light sources have photons with arrival times that are Poisson distributed. You are confusing the wave front of a light wave with a photon. The wave fronts of a coherent light wave is completely periodic. There is no randomness in the arrival of a wave front, at least not in a coherent light wave. The arrival of a wave front is not correlated with the arrival of the photon. > > http://www.merriam-webster.com/dictionary/coherent > Date: circa 1555 > 1 a : logically or aesthetically ordered or integrated : consistent > <coherent style> <a coherent argument> b : having clarity or intelligibility > : understandable <a coherent person> <a coherent passage> > 3 a : relating to or composed of waves having a constant difference in phase > <coherent light> Your dictionary did not say that "related to or composed of photons having a constant difference in phase." That is what you are claiming. I said: "related to or composed of waves have a constant difference in phase". Photons are particles. Wave packets can have phase. A photon is not a wave packet. What your dictionary meant by "waves" was "wave packets". If you are going to quote dictionary definitions, please rad them first. A coherent light wave is not an orderly progression of photons. The photons in a coherent light wave arrive randomly, in a Poisson distribution. I have heard coherent waves defined differently. Some scientists define coherent light waves as "a random, Poisson distributed stream of photons." You are the first person that I have seen that defines a coherent light wave as an orderly progression of photons. You don't want to see a link, so I won't give it. However, your definition violates many, many experimental results. A coherent light wave is composed of waves fronts that have a constant difference in phase. > > Please be coherent, drosen. <LOL> I am coherent. You are not. Your posts have been a random stream of insults. Insults are not arguments. > > If we double the rate of photon emission we can send 1 J of energy in half > the time, thereby doubling the POWER. Still the single cycle wave packet will continue to be a single cycle wave packet. Capitalizing the word "power" doesn't prove that you understand even the simplest electronics. Nor does it tell me anything about what you mean by "photon". > What is your problem with a radio wave being composed of single photons, one > after the other so that they all have a constant difference in phase, even > if they are big fat photons with lots of amplitude? Single photons have a fixed amplitude. You can't have a photon with lots of amplitude. The energy of a photon is fixed. Therefore, its amplitude is fixed. Photons are fat, now? "Lots of amplitude" corresponds to "obesity"? You are becoming less coherent every day!
From: Darwin123 on 3 Aug 2010 11:30
On Aug 3, 10:20 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Darwin123" <drosen0...(a)yahoo.com> wrote in message > > news:deae2524-8c0b-49c1-ba10-d6a4728552b4(a)d37g2000yqm.googlegroups.com... > On Aug 3, 1:52 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > > If it had meant photons, it would have said photons. > ====================================== > I added one cycle of a wave since I need two cycles > to be both necessary and sufficient to recognise phase. What? > > It said waves, not photons. > ======================================== > If it said "vehicle" it would include 18 wheelers and monocycles. If it said, "gas", it could not have included any 18 wheelers and monocycles. A "gas" is not a "vehicle". A "wave" is not a "photon". > > http://www.merriam-webster.com/dictionary/vehicle > : a means of carrying or transporting something <planes, trains, and other > vehicles> A "gas" is not a "means" of carrying anything. > > http://www.merriam-webster.com/dictionary/photon > > 2 : a quantum of electromagnetic radiation > > http://www.merriam-webster.com/dictionary/quantum > > 2 a : any of the very small increments or parcels into which many forms of > energy are subdivided b : any of the small subdivisions of a quantized > physical magnitude (as magnetic moment) Not even a single mention of the word "wave". > Waves include photons. Gases include vehicles? > > You are the one who added photons to the definition. > ============================================== > Yes, and I asked you what your problem was with that definition. My answer is that you are the only one who uses the word that way. The way you use the word "photon" contradicts every other definition ever given. > All you came up with was amplitude and paragraphs of lame >justification for your pathetic prejudice. Your definition contradicts the experimental results of everyone who has ever performed experimental studies of a photon. >"A roller skate is not a vehicle because it isn't > big enough." -- the mentality of drosen. A gas is a vhicle because it is a means of transporting atoms - the mentality of Androcles. > > A radio antenna works quantum mechanically by emitting one photon at a time, > coherently producing a wave train. > > What is your problem was with that definition, drosen? Photons are not waves. >Oh, I know... you > don't like big photons. Only atoms can emit photons, right, >drosen? I have repeated again and again that radio antenna can emit photons. What is your problem with my objections to your "definition of photon?" |