As opposed to what? Is a phonon any less real than a table? My point is that every human concept of the world resides in the mind ultimately, that even the term"table" is just a name we give to what or brains do with a certain collection of sensory inputs. Phonon is, of course, a lot less familiar concept and a lot less well tested since it is not directly observable.
Steven Desjardins Department of Chemistry Washington and Lee University Lexington, VA 24450 (540) 458-8873 FAX: (540) 458-8878 [EMAIL PROTECTED] >>> [EMAIL PROTECTED] 05/10/04 08:17PM >>> RE: Phonons... The idea of a phonon is like a ruler. There are no Phonons, there are no Inches, a ruler is just a stick with marks on it, but if it makes the right predictions than that's all the scientific method can deal with... http://www.cm.utexas.edu/~mcdevitt/supercon/glossary.htm#P The natural vibrations of a solid's crystal lattice. It's a term not a thing. -Shawn -----Original Message----- From: Steve Discarding [mailto:[EMAIL PROTECTED] Sent: Monday, May 10, 2004 9:53 AM To: [EMAIL PROTECTED] Subject: Re: how gravity works... They often do, using names like charm and color to describe properties of subatomic particles that simply have no analog in everyday life. Remember, most of these bizarre properties/object are terms in equations. They make predications about events in accelerators like "this particle will deflect this much due to this property". Since there are no macroscopic analogies, they have to make up names for things. A more accessible example is a "phonon" A phonon is a quantized vibration, like a sound wave. You can make phonons by banging your knuckles on the table top. It turns out that if you assume these vibrations are little particles you can make predictions that agree with many, many experiments. The agreement is easily good enough to use this theory to construct technological devices. This whole idea of sound waves being little particles may bother some, but if the internal logic is consistent and makes the correct predictions, then that's all the scientific method can deal with. It is important to remember that common sense only applies to common things, and not even them sometimes. The only real meaning of common sense is "that collection of empirical rules of thumb I/we have found useful to explaining the events of my daily life". "Science" imposes a much higher degree of logic/experimental precision on this process, and sometimes the results are surprising. >>> [EMAIL PROTECTED] 05/09/04 02:11PM >>> Hi, [...] > That's what I like about you guys. Something beyond explanation? Let's > make up an entity that explains it. Then, we'll go looking for it. > It's just so cool that these sorts of things are theoretical constructs at > first, then are proven through various observations/experiments. It's like, > "hey, given what we know of the mass of the universe, it's expanding too > slowly. There's some gravity out there we can't find. We'll "invent" black > matter, to explain it!" > "What's that you say? We need to "invent" grey matter to explain something > else? Okay, we can do that too". to paraphrase a song, they laughed at phlogiston. But to my naive mind it sounds as though the physicists just invent their own types of phlogiston. It might be easier to understand if they called it all x, or perhaps 'damnedifiknowon'. -- Cheers, Bob
