来源: 绚彩糖豆 于 2014-02-11 08:02:39
K娃糖豆对“物理知识”的感知(3)-Particles,Force,Field等
三个月前,K班第一次家长会,校长“突然出现”(我们不知情,是班主任安排的)。狠狠地给糖豆爹娘打了针鸡血!至于如何表扬咱家糖豆同学的?此处省略80分钟…… 最后握手道别的时候,校长笑道:“Who knows, he may be the one solving the mystery of ‘Dark Matter’!" 我?这校长也有心灵感应哈,咋知道糖豆前一天才对Dark Matter发表“建设性”speech呢!
那是去年11月份的一天, 第一次对糖豆提起“Dark Energy”时,他非常淡定地回答说:“And there is something called Dark Matter!”我就好奇了。糖豆妈我自己才扫的盲。他从哪里得来的消息?!就听糖豆继续说: “You can find them because light going near them will bend!” “Otherwise, the light will travel in the straight line if there is nothing there!” 糖豆说是从“Particle Zoo”(一个iPad App)里看来的:“I know that when I was 4!”小朋友的确有好记性。前一阵子当我read book,象发现新大陆般地告诉他:“Wow! There are six different kind of Quarks!”他扬起笑脸““Yeah! Up, down, bottom, top, charming and strange Quarks”! 他可是有将近一年没有去玩这个app了哈!
处于好奇,当天晚上我还是去搜出了这个app。找到了那个“Dark Matter”。看介绍非常简短,只写了这东东 “neither emits light; nor absorbs light”。哪里就提到Light bends when near it! ( 不过,YouTube的clip里的确是这么个意思)。趁着小猪泡澡高兴呢,我“似乎”灰常不经意地问他:“how do you know ‘light can bend around Dark Matter’?”他嘻嘻哈哈地,但简单明了地解释道: “Matter has mass. Mass has gravity. Gravity makes light bend.”
两天之后,从学校将糖豆接回家的路上,他突发感想: " THEY say ‘Dark Matter’ and ‘Dark Energy’ are two different things. But I think they’re the same!" 那啥,5岁娃居然敢怀疑科学家的话!他继续:"They (Dark Energy and Dark Matter)might be the same stuff doing opposite things. The ‘(Dark) Matter’ pulls the matters together, the ‘(Dark) Energy is pushing space (no matter) apart!" 糖豆爸对此的评价是:“无知者无畏啊!” 当晚,我在厨房一边准备晚餐,一边看iMac上 “The Dark Universe” 扫盲片。突然听到一句 "some theory puts these two together, called ‘Dark Fluid’." 哈!不管人科学家说的是否和我家K娃一个概念。先将糖豆爸拖过来洗脑,然后暴打一个毛栗子!叫你说糖豆“无知”!
下面说说糖豆对于常见particle的感知吧:
去年夏天,糖豆问为什么水是H2O, not O2H。当时我这个理科盲和他绕啊绕的,搞得一头雾水。(http://blog.wenxuecity.com/myblog/62002/201309/2760.html)由此,糖豆再次pick up了化学元素表。他这次主要是想学electron shell。第一次看见diagram,他小手指着electron cloud说道:“Oh! This (electron) has magnetic energy!” 那时候,他还没有接触过EM呢。天晓得他从哪里听来的!
听了啥叫“Quantum Leap”,小子不学好,哈哈大笑道:““Electron pooped out Photon, like lost energy, so electron goes down a shell level. But when electron eat a Photon, it gains energy, so it goes up a shell level!” (是的,糖豆同学还处于“神马东西都和Poop,Peepee扯上关系的tender age。)
当我告诉他“Photons don’t have mass, they are not considered as matters.”,他的第一反应是:“Then how about x-ray?” 小同学还没有学过Electron-Magnetic Spectrum 的知识呢。 咋就将visible和invisible的light都归类了呢。问他怎么想出这个问题的,他耸耸肩:“It just popped into my brain!”
一周后,终于让糖豆看了EM的扫盲片。里面提及了Frequency,wavelength等等,正好和他自学的Trig function中的graphing关联起来。当时一看见最简单的那种sine function’s graph,amplitude, frequency和phase的关系。小朋友立马说:“increasing frequency will affect the period!—— It decreases the period.” 然后说:“The higher the frequency, the more dangerous that EM wave is! Such as Gamma Ray.” 现在真的知道了为什么理论物理学家必须要有好的数学功底,或必须要有一个数学超强的老婆(看Einstein传有感!呵呵呵)
也还是去年底的时候。我问他:“哪个 particle responsible for the Electromagnetic Force?” 他头也没抬:“Electron”!但,马上,他将注意力从iPad上移开了,灿烂的笑脸,眼睛亮亮地纠正自己:“Oh! Not electron! It is photon!” 天晓得啊!我这是刚从物理书里5秒钟前才批发来的知识啊,原本想抖一抖的…… 不久,提起CERN发现了Higgs Boson。 我问他知不知道什么是Higgs Boson,他乐:“Yeah! That Boson is giving Higgs Field!” 说实话,我真想知道他是如何搞清楚 “Field” 和“Particles”,还有“force”的关系的。
昨晚,糖豆在看“Who was Einstein”的书。里面提起Einstein在Teen的时候就发表了第一篇学术论文:推翻了过去Scientists认为的Space里有Ether的理论。Einstein认为“Empty Space is Empty”。他问我:“Is that true?”我真不敢瞎说,只能说:“还是个unknown吧。Einstein也有那个时代的limitation,technology一直在发展的……”还没等我说完呢,他笑着说:“Yeah!Otherwise it would be ‘Einstein Boson’, Not ‘Higgs Boson’了!”(Higgs Boson可能fill了Space,它的Field给了Matters Mass。)至于Mass 和Weight之间的关系,糖豆同学在“小时候”已经搞得很清楚了。