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wave-particle duality and TV reception
The whole science of RF seems to be based on wave theory. Does particle
theory have any place? Discuss. Bill |
wave-particle duality and TV reception
I thought the particle aspect of radio, or electromagnetic 'stuff', was that
the wave function is just the outcome of approximating the energy and the quantum state, or guess of the position of the particle. it only becomes a particle in a given place when something makes it become actually visible. I've thought for a long time that time itself moves in jumps, but the actual universe is in motion between our snapshots of the situation. Since we are made of the stuff that is in motion, it is going to be hard for us to pin anything down, as by definition it takes time to measure things, and all I can see is that the universe has motion often affected by its temperature. cool stuff enough and it acts like a single atom. Unfortunately we cannot cool anything below a fraction of a percent above absolute zero, as in order to cool things you need a place to be colder that the item you cool which is impossible. Yes, I saw the programme as well, before the second episode I need to watch it again, it might be different next time, and the more times I watch it the more precisely I'll know what I don't know. Brian -- From the Sofa of Brian Gaff Reply address is active "Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? Discuss. Bill |
wave-particle duality and TV reception
"Bill Wright" wrote in message
... The whole science of RF seems to be based on wave theory. Does particle theory have any place? Discuss. Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. -- Woody harrogate three at ntlworld dot com |
wave-particle duality and TV reception
Are we going to see that old demo of the diy microwave? The one where a
waveguide is terminated by a sausage which gets cooked. Mind you, it could well be a health and safety nightmare these days. Brian -- From the Sofa of Brian Gaff Reply address is active "Woody" wrote in message ... "Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? Discuss. Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. -- Woody harrogate three at ntlworld dot com |
wave-particle duality and TV reception
Brian Gaff wrote:
Snip Yes, I saw the programme as well, before the second episode I need to watch it again, it might be different next time, and the more times I watch it the more precisely I'll know what I don't know. Brian Surely the process of observing the programme will change it. -- Ashley |
wave-particle duality and TV reception
In article , Bill Wright
wrote: The whole science of RF seems to be based on wave theory. Does particle theory have any place? In general the frequency ranges and power levels associated with 'RF' tends to mean that you get a lot of photons for yer money. :-) So in practice the photon approach only matters much in some specific fairly extreme cases. e.g. if you're trying to work with ultra low signal levels at very high frequencies and photon shot noise becomes a limit. More usually the coherent properties matter far more, so wave theory makes more sense. That said, one possible place for photons is in 'explaining' the currently trendy ideas of 'microwave beams with angular momentum'. But if you look into that bear in mind that some of what it said may look baffling because it is what academic jargon would call 'baloney'. :-) Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
I'd prefer a demonstration of Nicholas Kurti's inverted baked Alaska -
meringue cooked inside ice-cream, showing how microwaves are differentially absorbed by ice and water. Would be even better if the demonstration achieved Kurti's - probably mythical - goal of using helium to acheive lighter-than-air meringue! -- Robin reply to address is (meant to be) valid |
wave-particle duality and TV reception
In article ,
Robin wrote: I'd prefer a demonstration of Nicholas Kurti's inverted baked Alaska - meringue cooked inside ice-cream, showing how microwaves are differentially absorbed by ice and water. Would be even better if the demonstration achieved Kurti's - probably mythical - goal of using helium to acheive lighter-than-air meringue! how would you get them down from the ceiling? -- From KT24 Using a RISC OS computer running v5.18 |
wave-particle duality and TV reception
On Thu, 11 Dec 2014 08:12:29 -0000, "Woody"
wrote: Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. Yes, I find it genuinely encouraging that such creatures exist, as in all the time I spent in broadcast engineering, I never met one. I don't mean just professors of course; there were never female versions of any kind of engineer (except a few I recruited myself, which probably doesn't really count). I expect the usual suspects, notably in the Guardian, will make the usual noises about this, suggesting that the reason for it is some kind of fiendish male plot to keep the girlies away from our technical toys, but I've never seen any evidence of any such thing, rather the reverse if anything. My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. Rod. |
wave-particle duality and TV reception
Jim Lesurf wrote:
In article , Bill Wright wrote: The whole science of RF seems to be based on wave theory. Does particle theory have any place? In general the frequency ranges and power levels associated with 'RF' tends to mean that you get a lot of photons for yer money. :-) So in practice the photon approach only matters much in some specific fairly extreme cases. e.g. if you're trying to work with ultra low signal levels at very high frequencies and photon shot noise becomes a limit. More usually the coherent properties matter far more, so wave theory makes more sense. Jim Thanks for that. Bill |
wave-particle duality and TV reception
In article , Roderick Stewart
wrote: My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. However that still may be a 'conditioned response' which is indoctrinated long before they approach the end of schooling. The young tend to pick up their ideas from their peers and the ones who are a year or two older at school. Hence may be acquired as just one part of a general social set of fitting in. IIRC the stats indicate that women are far more likely to take an interest in 'science' if they went to a single-sex school. After that they tend to run into the assumptions, etc, in workplaces, etc. Again, as a part of the general taken-for-granted assumptions of society. Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
On Thu, 11 Dec 2014 10:09:53 +0000 (GMT), Jim Lesurf
wrote: In article , Bill Wright wrote: The whole science of RF seems to be based on wave theory. Does particle theory have any place? In general the frequency ranges and power levels associated with 'RF' tends to mean that you get a lot of photons for yer money. :-) So in practice the photon approach only matters much in some specific fairly extreme cases. e.g. if you're trying to work with ultra low signal levels at very high frequencies and photon shot noise becomes a limit. More usually the coherent properties matter far more, so wave theory makes more sense. That said, one possible place for photons is in 'explaining' the currently trendy ideas of 'microwave beams with angular momentum'. But if you look into that bear in mind that some of what it said may look baffling because it is what academic jargon would call 'baloney'. :-) Which neatly takes us back to that 'sausage reference' again. :-) -- J B Good |
wave-particle duality and TV reception
In article ,
Roderick Stewart wrote: On Thu, 11 Dec 2014 08:12:29 -0000, "Woody" wrote: Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. Yes, I find it genuinely encouraging that such creatures exist, as in all the time I spent in broadcast engineering, I never met one. we had one in our department for a couple of years and there was another with TCPD in Warwick whom I talked to on the phone fairly often. I met her once at an RF Safety Conference at ERA. She was the only women aout of soem 50 engineers. -- From KT24 Using a RISC OS computer running v5.18 |
wave-particle duality and TV reception
Now you are just being silly. However waveguide theory seems to be
suggestive of um, waves, not particles, its probably something really obvious that is cocking up the theories . Brian -- From the Sofa of Brian Gaff Reply address is active "Robin" wrote in message ... I'd prefer a demonstration of Nicholas Kurti's inverted baked Alaska - meringue cooked inside ice-cream, showing how microwaves are differentially absorbed by ice and water. Would be even better if the demonstration achieved Kurti's - probably mythical - goal of using helium to acheive lighter-than-air meringue! -- Robin reply to address is (meant to be) valid |
wave-particle duality and TV reception
Silly? Well if I recall rightly he demonstrated the inverted baked
Alaska on TV in 1969 - and I used to know people who'd had it at his dinner parties. As regards the use of helium to make meringue, do please bear in mind this was a man who regularly made them using a vacuum chamber. He was a colourful lecturers too (but sadly IME never brought food to share). -- Robin reply to address is (meant to be) valid |
wave-particle duality and TV reception
how would you get them down from the ceiling?
I wouldn't have put it past Kurti to serve them with a sauce made with heavy water :) -- Robin reply to address is (meant to be) valid |
wave-particle duality and TV reception
"charles" wrote in message
... In article , Roderick Stewart wrote: On Thu, 11 Dec 2014 08:12:29 -0000, "Woody" wrote: Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. Yes, I find it genuinely encouraging that such creatures exist, as in all the time I spent in broadcast engineering, I never met one. we had one in our department for a couple of years and there was another with TCPD in Warwick whom I talked to on the phone fairly often. I met her once at an RF Safety Conference at ERA. She was the only women aout of soem 50 engineers. As a trainee at Pye back in the 70's I used to work with a girl who tested (and fixed!) 130W mobile HF transceivers, and boy was she good! More recently my last employer decided to take on some apprentices one of which I'm glad to say I spotted when she came to an open evening. She is now a qualified electrician and with the retirement of her mentor she is the area sparks and still only in her mid/late 20's. I saw her a couple of weeks ago and she is having a whale of a time. As said before, I think much of it is conditioning in the early part of senior school as few teachers have ever had experience of anything else. One of the best lecturers I ever had at Tech had been a design and lab engineer dealing with servo and associated control systems with GEC before moving into education. Just shows...............? -- Woody harrogate three at ntlworld dot com |
wave-particle duality and TV reception
Jim Lesurf wrote:
My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. However that still may be a 'conditioned response' which is indoctrinated long before they approach the end of schooling. The young tend to pick up their ideas from their peers and the ones who are a year or two older at school. Hence may be acquired as just one part of a general social set of fitting in. I did a lot to avoid sexual stereotyping with my kids. It made no difference. The girls developed girly interests; the boy developed masculine interests. Of course, parents are only one influence on a child, and in any case they probably model themselves on their parents. Bill |
wave-particle duality and TV reception
On Thursday, 11 December 2014 05:25:36 UTC, Bill Wright wrote:
The whole science of RF seems to be based on wave theory. Does particle theory have any place? Discuss. Bill Waves, particles, neither, both? Who knows? Treating EM waves as "waves" makes the maths easier,(for some value of easier), for calculating aerial lengths, diffraction, etc. But you can turn it around and say something like:- The transmitter emits a stream of photons, some of which bang into the recieving aerial and knock electrons out of their orbits around the atoms. These bang into the next atom up, and then the next, and if you get enough of them, you end up with an electric current to feed into the receiver. Simples! It was a good program, though. Except I got lost at Bell's inequality. Remember photons, electrons and such are not things as we understand it. Just as radio waves are not waves as we understand them, as they're not waves IN anything. Trying to think about it hurts the head. As someone famous said:- If you're not shocked by Quantum theory, you haven't understood it. I think someone else said "No-one really understands it at all". Good thinking, Ian. |
wave-particle duality and TV reception
On Thu, 11 Dec 2014 18:51:10 -0000, "Woody"
wrote: "charles" wrote in message . .. In article , Roderick Stewart wrote: On Thu, 11 Dec 2014 08:12:29 -0000, "Woody" wrote: Looks like the RS Christmas Lectures this year will be interesting - being delivered by a woman (name escapes me) who is Professor of Radio Frequency Engineering at UMIST. Yes, I find it genuinely encouraging that such creatures exist, as in all the time I spent in broadcast engineering, I never met one. we had one in our department for a couple of years and there was another with TCPD in Warwick whom I talked to on the phone fairly often. I met her once at an RF Safety Conference at ERA. She was the only women aout of soem 50 engineers. As a trainee at Pye back in the 70's I used to work with a girl who tested (and fixed!) 130W mobile HF transceivers, and boy was she good! More recently my last employer decided to take on some apprentices one of which I'm glad to say I spotted when she came to an open evening. She is now a qualified electrician and with the retirement of her mentor she is the area sparks and still only in her mid/late 20's. I saw her a couple of weeks ago and she is having a whale of a time. As said before, I think much of it is conditioning in the early part of senior school as few teachers have ever had experience of anything else. One of the best lecturers I ever had at Tech had been a design and lab engineer dealing with servo and associated control systems with GEC before moving into education. Just shows...............? One evening, with his charge at full capacity, Micro Farad decided to get a cute coil to discharge him. He went to the Magnet Bar to pick up a chip called Millie Amp. He caught her out back trying self induction; fortunately, she had not damaged her solenoid. The two took off on his megacycle and rode across the Wheatstone Bridge into a magnetic field, next to a flowing current , to watch the sine waves. Micro Farad was very much stimulated by Millie's characteristic curve. Being attractive himself, he soon had her field fully excited. He set her on the ground potential, raised his frequency, lowered her resistance, and pulled out his high voltage probe. When he inserted it in parallel, he short-circuited her shunt. Fully excited, Millie cried out, "ohm, ohm, give me mho". As he increased his tube to maximum output, her coil vibrated from the current flow. It did not take long for her shunt to reach maximum heat. Now with the excessive current shortening her shunt, Micro's capacity rapidly discharged – every electron was drained off. But that was not the end of it. Indeed, they fluxed all night, tried various connections and hookings until his bar magnet weakened, and he could no longer generate enough voltage to sustain his collapsing field. With his battery fully discharged, Micro was unable to excite his tickler, so they went home. A few weeks later, they were merged forever and oscillated happily ever after. -- Graham. %Profound_observation% |
wave-particle duality and TV reception
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wave-particle duality and TV reception
"Robin" wrote in message
... Silly? Well if I recall rightly he demonstrated the inverted baked Alaska on TV in 1969 - and I used to know people who'd had it at his dinner parties. Rather pointless as you could just put the ice cream on afterwards. -- Max Demian |
wave-particle duality and TV reception
"Bill Wright" wrote in message
... The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. -- Max Demian |
wave-particle duality and TV reception
On 11/12/14 10:09, Jim Lesurf wrote:
So in practice the photon approach only matters much in some specific fairly extreme cases. e.g. if you're trying to work with ultra low signal levels at very high frequencies and photon shot noise becomes a limit. If I interpret http://www.coseti.org/9006-005.htm correctly, and using an efficiency of 1, rather than 0.5, I get the effective noise temperature as about 0.6K, for a DBS system. That is a lot less than the open sky limit of 3K, and much much lower than achievable system noise temperatures. |
wave-particle duality and TV reception
That no doubt is his training when he was wit e Atomic energy authority.
Brian -- From the Sofa of Brian Gaff Reply address is active "Max Demian" wrote in message ... "Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. -- Max Demian |
wave-particle duality and TV reception
On 12/12/14 10:00, brightside S9 wrote:
Reflection from a non smooth surface. What are the particle aspects of that? It is generally easiest to analyse as a wave phenomenum, especially when the surface and its roughness are similar to, or less than, the wavelength. |
wave-particle duality and TV reception
On Thu, 11 Dec 2014 14:02:09 +0000 (GMT), Jim Lesurf
wrote: My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. However that still may be a 'conditioned response' which is indoctrinated long before they approach the end of schooling. The young tend to pick up their ideas from their peers and the ones who are a year or two older at school. Hence may be acquired as just one part of a general social set of fitting in. So where do their peers get it from? I've got peers too you know, and have managed with no difficulty to ignore the preferences of most of them, thus ending up with no interest in football, pop music, fishing, sports cars, drinking 10 pints in pubs and getting into fights, and many of the other blokey things that blokey blokes are traditionally supposed to like. One of my favourite inspirational books is called "What do you care what other people think?". What I do like to think is that I have a mind of my own so don't need to copy other people's. If I can do this, then so can anybody else, but look around you and see who does, and who doesn't. If what you say is true, and "fitting in" is more important to some people than following their own paths, then that's their choice, not anybody else's imposition. Rod. |
wave-particle duality and TV reception
Max Demian wrote:
"Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. There's been a lot of stories recently about scientists fiddling their results! Apparently a lot of them admit to it, years later. Bill |
wave-particle duality and TV reception
In article , Bill Wright
wrote: Jim Lesurf wrote: My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. However that still may be a 'conditioned response' which is indoctrinated long before they approach the end of schooling. The young tend to pick up their ideas from their peers and the ones who are a year or two older at school. Hence may be acquired as just one part of a general social set of fitting in. I did a lot to avoid sexual stereotyping with my kids. It made no difference. The girls developed girly interests; the boy developed masculine interests. Of course, parents are only one influence on a child, and in any case they probably model themselves on their parents. They also tend to pick up a lot of assumptions from the other kids at school about how to behave and what they should 'like'. That's one reason why the results from single-sex schools tend to differ from mixed. Jim Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
In article ,
wrote: It was a good program, though. Except I got lost at Bell's inequality. You're in good company! Most people get baffled by any attempt to explain it! Including most professional research physicists. 8-] He may have erred on the side of giving too few details, so omitting some that may have helped. But giving more details may simply mean more ways to confuse people. Some things just aren't that easy to explain, alas. I'd have preferred him to say more about the actual experimental details so people could chew them and see if that helped. But it would risk losing people along the way as they got bored by arcane details or lost. FWIW Personally I'm quite happy with 'spooky action at a distance' as I *want* there to be mechanisms that 'communicate' relationships 'faster than the speed of light'. TBH I'm not really convinced by the blanket assertion that the speed of light is an absolute limit for *every* form of this. I suspect that the QM tangling is just a hint of this. Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
In article , David Woolley
wrote: On 11/12/14 10:09, Jim Lesurf wrote: So in practice the photon approach only matters much in some specific fairly extreme cases. e.g. if you're trying to work with ultra low signal levels at very high frequencies and photon shot noise becomes a limit. If I interpret http://www.coseti.org/9006-005.htm correctly, and using an efficiency of 1, rather than 0.5, I get the effective noise temperature as about 0.6K, for a DBS system. That is a lot less than the open sky limit of 3K, and much much lower than achievable system noise temperatures. Happy to accept your figures. They show the reason why people generally ignore 'photons' in RF. FWIW I've had to take them into account in the past as my early work was on 'far infrared' detectors that were cooled to 3K or lower to work, then pointed at a clear sky. In such cases photons may end up limiting such measurements. And indeed, the signal being measured might be photon counted when you move to nearer IR. But this isn't likely to spoil your ability to watch UHF Freeview. :-) Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
Max Demian wrote:
"Bill Wright" wrote: The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. From the look of the mangled bean cans he'd practised with the blue golf balls beforehand. |
wave-particle duality and TV reception
In article , Roderick Stewart
wrote: On Thu, 11 Dec 2014 14:02:09 +0000 (GMT), Jim Lesurf wrote: My life's experience, all the way from childhood, would suggest that most girls and women avoid involvement in technology because most of them are simply not interested. However that still may be a 'conditioned response' which is indoctrinated long before they approach the end of schooling. The young tend to pick up their ideas from their peers and the ones who are a year or two older at school. Hence may be acquired as just one part of a general social set of fitting in. So where do their peers get it from? Schools tend to have a set of cohorts across some years. Thus each new year of intake tends to pick up established ways from the kids who started in previous years. to like. One of my favourite inspirational books is called "What do you care what other people think?". If you mean Feynman, I also have a copy. Alas I fear most junior school kids won't think that way or have read a copy. More commonly, 'rebellion' for kids is 'not agreeing with your parents/teachers' usually about something trivial like musical taste or haircut. What I do like to think is that I have a mind of my own so don't need to copy other people's. If I can do this, then so can anybody else, but look around you and see who does, and who doesn't. If what you say is true, and "fitting in" is more important to some people than following their own paths, then that's their choice, not anybody else's imposition. I can't recally saying anyone was systematically and intentionally doing it. Just that it seems common human behaviour when you colllect a range of kids of different ages into a school and let them interact. Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
In article , Bill Wright
wrote: Max Demian wrote: "Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. There's been a lot of stories recently about scientists fiddling their results! Apparently a lot of them admit to it, years later. OK, I confess that when I took my English Language O-Level I fibbed. I didn't really want to be a train driver. I just wrote that in my essay for effect. :-) Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
"Bill Wright" wrote in message
... Max Demian wrote: "Bill Wright" wrote in message ... The whole science of RF seems to be based on wave theory. Does particle theory have any place? It looked as if he deliberately missed the tin cans with the red ping pong balls. There's been a lot of stories recently about scientists fiddling their results! Apparently a lot of them admit to it, years later. At uni we learned that Mendel probably cheated in his pea breeding experiments. -- Max Demian |
wave-particle duality and TV reception
On 12/12/14 13:21, brightside S9 wrote:
For reflections from non smooth surfaces, with roughness much greater than the wavelength, the reflection is from the whole surface. But it is not a simple(ish) mathemetical problem to analyse the resultant reflected waves and build a picture of what gets to the receiver (for example a viewer of reflections from rippling water). In this example it is simpler to use the particle theory, and angle of incidence equals angle of reflection rule. That only applies when the surface is essentially locally flat at the wavelength in question and is large in relation to the wavelength. |
wave-particle duality and TV reception
On 12/12/14 13:21, brightside S9 wrote:
Unless anyone knows of some exotic material that has a photoelectric effect when hit with RF. masers. atomic clocks. quadrupole resonance spectroscopy. MRI. These all tend to depend on spin flips, rather than knocking electrons out. |
wave-particle duality and TV reception
In article , David Woolley
wrote: On 12/12/14 13:21, brightside S9 wrote: For reflections from non smooth surfaces, with roughness much greater than the wavelength, the reflection is from the whole surface. But it is not a simple(ish) mathemetical problem to analyse the resultant reflected waves and build a picture of what gets to the receiver (for example a viewer of reflections from rippling water). In this example it is simpler to use the particle theory, and angle of incidence equals angle of reflection rule. That only applies when the surface is essentially locally flat at the wavelength in question and is large in relation to the wavelength. The idea that angle of incidence = angle of reflection is really a part of simple geometric ray theory, not of wave theory. It can be based on either, given suitable simplifying assumptions. Wave 'theory' actually comes in various forms which then get used according to the circumstances. Ditto in fact for ray theories. In general physicists and engineers dodge having to solve Maxwell's Equations if they can as it can be a real PITA except in simple situations. So we have a gang of wave and ray theories to pick from, depending on the case. I used to point out in tutorials in the past that photons were far smarter than people. They can 'solve' Maxwell's equations far more quickly when they have to work out how to deal with hitting a window. :-) Jim -- Please use the address on the audiomisc page if you wish to email me. Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html Audio Misc http://www.audiomisc.co.uk/index.html |
wave-particle duality and TV reception
Jim Lesurf wrote:
But this isn't likely to spoil your ability to watch UHF Freeview. :-) Jim Could we market our aerials as photon beam collectors? Bill |
wave-particle duality and TV reception
Jim Lesurf wrote:
Schools tend to have a set of cohorts across some years. Thus each new year of intake tends to pick up established ways from the kids who started in previous years. Playground games go through the cohorts, year after year, sometimes almost unchanged for generations. Bill |
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