物理就是无理

字体 -

在我刚刚登陆多伦多时,ESL老师说了一句让我终生难忘的话:你应该了解你所生活的城市!说实在的,我在中国的好几个大城市和农村都生活过,却从来没有仔细想过这个问题,也没有刻意要去了解所在的城市;在哪里生活不都一样,都是俗人、房子和车子,有什么好了解的?稀里糊涂或者明明白白过几十年又有什么差别?

然而,世界这么大,不出去走走看看,不去了解一番,这一世岂不是白来一趟?地球有多大,太阳系有多大,银河系又有多大?Local Group 听说过吗?Walls of Galaxies 又是什么?一个人,才多大一点啊?还那么傲慢自大!

弄清宇宙的组成和运作,正是物理学的根本目的。这何偿又不是其它学科的目的呢?天文、地理、化学、生物,都是在了解不同的对像而已。怎么去了解呢?听别人讲解?还是自己亲手做实验?物理学不相信理论,只相信眼见为实的实验;既是实验,不同的人在不同条件下得出的结果,其准确度就难以让人信服。物理中的等号(=)其实都是近似等号(),有的物理学者甚至分不清大于号(>)和小于号(<)。

怎么记录你所了解的东西呢?当然是用记号。如你所知,为了准确性,记号最终都变成了数字。看看书店里的所谓科学著作,许多都是夸夸其谈,没有半个数字。对于这种书,我是翻一下就扔一边的。稍微有点数量意识的,也大都是说,这个与那个成正比,或者与第三者的平方成反比;至于那个比例系数呢,做几次实验取个平均值,再拿个人名来做单位就行了。更有甚者说,以我本人的名字做单位,比例系数就是1

列个方程就真的那么难吗?对于可观测的东西(也就是能够与电磁波有相互作用的东西),只要有个记时器,从某个事件的外部影响因素和内部结构两个方面来考虑,就可以得出近似方程;准确方程就用无穷级数逼近啊,能算几项是几项。我小时候玩的炸洋碗的游戏,就完全可以测定爆炸力、万有引力、空气阻力,还有大气压力。

对于不可观测的东西,现在使用的有两种办法。一是臆想中的实验,比如爱因斯坦的相对论。我一直不相信他用勾股定理推出的时间延长公式,但又说不出他错在哪里;现在才明白错在两处:一是相对速度是有方向的,你不能假设光线与相对速度的方向垂直;所以不能用勾股定理,而是要用一般的余弦定理。二是相对速度的测定必须依赖于第三方的、一个共同的参照系。因此,相对论仍然是近似的。

第二种方法是公理法。比如,实数的理论就是建立在7条相互等价的公理之上的,化学也有自己最基本的假设,那就是原子不灭。物理中的公理是什么呢?力学要推虎克定律和牛顿第二定律,电磁学要推库伦定律和Biot-Savart定律,但是这些所谓成正比例关系的定律,对其精确度,我是一直不敢恭维的。自然科学中,如果要说有公理的话,那就只有能量守恒定律。物理学家们为什么不去推导它在各种物质形态中的表现,再加以实验验证呢?

对于我们连臆想都想不到的东西,比如暗物质和暗能量,该怎么去了解呢?是不是干脆说它们不存在就万事大吉了?我在一次数学课上给几个5年级学生讲圆锥体积的实验求法,说到用三个同底等高的圆锥去灌满一个圆柱;一个学生说,可能相差一个水分子;另一个学生说,还可能少了一个氢原子呢!第三个学生干脆说,我才不在乎呢,分子原子的差别谁能感觉得到?

学过微积分的人都知道,准确的求法是微元法。物质的组成是有最小单位的,不是夸克,也不是弦,而是微元。微元如何生成质量呢?靠Higgs Boson去赋予?微元如何生成电量呢?靠大爆炸的推动力?还是靠不可捉摸的量子纠缠?

一个八年级学生在学校学完圆之后回到家里,家长想考考他,就拿了一个锅盖让他去求出周长。学生找来一根皮尺,想去量出直径,却怎么也找不到圆心,因为学校老师并没有教过。家长说,你拿皮尺直接去量圆周不就行了,要量什么直径啊!我们只知道周长等于直径乘以圆周率,却不知道圆周率的定义是基于相似图形。其实,再多学一点圆内角的知识,找圆心易于反掌;再多学一点微分几何的知识,你就能证明,直径其实就是圆内最长的线段。

从一个基本点出发,用类比的方法去推理,我们就能明白世间的一切。公理只有一个:物由两极而生,中间有最优化的第三态。因为一物的存在需要另一物的体现,一个量的检测需要另外一个量来比较。宇宙被上天设计成了这样,人类只不过是诸多观察者中微不足道的一个。

分享博文至:

    65 条评论

  1. 1. mexico resorts vacation packages - 2018年3月3日 05:26

    Discover opinions for Mexico family holidays.

  2. 2. Carri - 2018年3月7日 06:33

    Hello! I know this is kind of off topic but I was wondering if you knew where I could find a captcha plugin for my comment form? I’m using the same blog platform as yours and I’m having difficulty finding one? Thanks a lot!

  3. 3. zippyaudio unblocked - 2018年3月19日 22:04

    Start trying to find petting sitting, free.

  4. 4. rv towing service near me - 2018年3月21日 05:59

    We’re your finest towing firm in Atlanta.

  5. Hardware wallets are secure, offline gadgets.

  6. 6. blockchain technology stocks nasdaq - 2018年3月22日 13:59

    Supplies access to all the Bitcoin blockchain.

  7. 7. blockchain technology stocks 2018 - 2018年3月23日 20:25

    Provides entry to the whole Bitcoin blockchain.

  8. 8. perez tree service atlanta ga - 2018年3月24日 21:14

    Professionals should deal with tree service.

  9. 9. water filtration system for home costco - 2018年3月29日 00:03

    Tap water shouldn’t be cleaner than bottled water.

  10. 10. trash removal companies in wilmington delaware - 2018年3月30日 02:22

    SDI is a Full Service Waste Management company.

  11. 11. water equipment & treatment services inc - 2018年3月31日 10:46

    We did not discover results for: water remedy companies.

  12. 12. tow truck services cost - 2018年4月3日 16:29

    Tow Truck & Wrecker Towing Service Acres Houses TX.

  13. 13. lawn care needed near me - 2018年4月5日 13:22

    Prepay and Save on TruGreen Garden Providers.

  14. 14. floor finishing cost - 2018年4月7日 03:39

    The newest pattern is to go for concrete flooring.

  15. 15. water treatment specialist jobs in uae - 2018年4月9日 11:33

    Operates and maintains water therapy equipment.

  16. 16. basement waterproofing diy - 2018年4月10日 03:59

    There are various kinds of basement waterproofing.

  17. 17. basement waterproofing products - 2018年4月11日 04:51

    Water seepage from your basement partitions or flooring.

  18. 18. tow truck service mesa az - 2018年4月12日 20:56

    Tow Truck & Wrecker Towing Service Greenspoint TX.

  19. 19. mold removal home depot - 2018年4月17日 11:46

    Black Mold Clear up can a be a challenging job.

  20. 20. mold removal spray for bathroom - 2018年4月21日 08:36

    Mold spores is not going to survive in dry climates.

  21. 21. wright tree service jackson mi - 2018年4月30日 02:18

    Let’s face it, lawn care services abound.

  22. 22. basement floor finishing products - 2018年5月1日 13:09

    They can harm the finish and warp a hardwood flooring.

  23. 23. tree companies atlanta ga - 2018年5月4日 02:11

    Glorioso Tree Service is a INCREDIBLE firm.

  24. 24. garage floor refinishing cost - 2018年5月5日 06:55

    Your floor undoubtedly wants refinishing, and soon.

  25. 25. tree cutting service cost - 2018年5月5日 09:11

    They just lately took down three massive bushes from my yard.

  26. 26. download mp3 instrumentals songs - 2018年5月8日 02:30

    The encoder compresses the song into the MP3 format.

  27. 27. tree cutting service - 2018年5月11日 20:46

    Welcome to Farage Tree & Stump Elimination.

  28. 28. mold removal from wood - 2018年5月14日 17:17

    Apply baking soda directly to moldy surfaces.

  29. 29. home theater systems deals - 2018年7月11日 05:23

    Next, try the sound of your speakers.

  30. 30. accounting and bookkeeping principles (us) - 2018年7月15日 16:47

    The double entry system makes use of nominal ledger accounts.

  31. 31. minecraft - 2018年9月11日 15:02

    It’s a pity you don’t have a donate button! I’d definitely donate to this fantastic blog! I guess for now i’ll settle for book-marking and adding your RSS feed to my Google account. I look forward to brand new updates and will talk about this site with my Facebook group. Talk soon!

  32. 32. minecraft - 2018年10月1日 03:12

    I am sure this post has touched all the internet viewers, its really really fastidious post on building up new weblog.

  33. 33. minecraft - 2018年10月1日 08:34

    Greetings from Los angeles! I’m bored to tears at work so I decided to check out your site on my iphone during lunch break. I love the information you present here and can’t wait to take a look when I get home. I’m surprised at how fast your blog loaded on my phone .. I’m not even using WIFI, just 3G .. Anyhow, superb blog!

  34. 34. minecraft free download 2018 - 2018年10月11日 03:48

    Wonderful website. A lot of useful information here.

    I am sending it to a few pals ans additionally sharing in delicious. And obviously, thank you in your effort!

  35. 35. tinder dating site - 2018年10月16日 10:06

    Attractive component of content. I simply stumbled upon your blog and in accession capital to say that I get actually enjoyed account your weblog posts. Any way I’ll be subscribing to your feeds and even I success you get admission to consistently quickly.

  36. 36. Coconut Oil - 2018年10月21日 12:50

    I always spent my half an hour to read this website’s articles everyday along with a mug of coffee.

  37. 37. Quest Bars Cheap - 2018年11月6日 23:37

    Hello there! This article couldn’t be written much better! Going through this post reminds me of my previous roommate! He constantly kept preaching about this. I’ll send this article to him. Pretty sure he’ll have a great read. Thanks for sharing!

  38. 38. Sling TV - 2018年11月11日 01:32

    First of all I want to say fantastic blog! I had a quick question in which I’d like to ask if you do not mind. I was interested to know how you center yourself and clear your head before writing. I’ve had a tough time clearing my thoughts in getting my thoughts out. I do enjoy writing however it just seems like the first 10 to 15 minutes are generally lost just trying to figure out how to begin. Any recommendations or tips? Appreciate it!

  39. 39. What Equipment is Needed for Sling TV - 2018年11月17日 08:30

    Howdy would you mind letting me know which webhost you’re working with? I’ve loaded your blog in 3 completely different internet browsers and I must say this blog loads a lot quicker then most. Can you suggest a good hosting provider at a reasonable price? Thanks a lot, I appreciate it!

  40. 40. Sling TV - 2018年12月5日 22:27

    I like reading an article that will make people think. Also, thanks for allowing me to comment!

  41. 41. minecraft - 2019年4月14日 03:40

    Have you ever thought about adding a little bit more than just your articles? I mean, what you say is fundamental and everything. Nevertheless think about if you added some great images or videos to give your posts more, “pop”!

    Your content is excellent but with images and videos, this blog could certainly be one of the greatest in its niche. Awesome blog!

  42. 42. tinyurl.com - 2019年4月14日 16:51

    Very nice post. I just stumbled upon your blog and wished to say that I’ve really enjoyed browsing your blog posts. In any case I will be subscribing to your feed and I hope you write again very soon!

  43. 43. minecraft - 2019年4月18日 13:12

    you are really a good webmaster. The site loading velocity is incredible. It sort of feels that you are doing any distinctive trick.

    Furthermore, The contents are masterwork. you’ve performed a magnificent job on this topic!

  44. 44. minecraft - 2019年4月23日 10:43

    I believe that is among the most important information for me. And i am happy studying your article. However want to statement on few basic things, The site taste is great, the articles is in point of fact great : D. Excellent task, cheers

  45. 45. quest bars - 2019年6月16日 12:31

    My brother recommended I might like this web site. He was entirely right. This post actually made my day. You cann’t imagine just how much time I had spent for this information! Thanks!

  46. 46. how to get help in windows 10 - 2019年7月16日 08:16

    This design is spectacular! You certainly know how to keep a reader entertained. Between your wit and your videos, I was almost moved to start my own blog (well, almost…HaHa!) Excellent job. I really enjoyed what you had to say, and more than that, how you presented it. Too cool!

  47. 47. pof https://natalielise.tumblr.com - 2019年8月1日 07:03

    Great article, just what I needed. pof natalielise

  48. 48. minecraft games - 2019年8月18日 18:13

    Thanks for sharing such a good thought, post is fastidious, thats why i have read it completely

  49. 49. minecraft games - 2019年9月1日 13:09

    Hello to all, how is everything, I think every one is getting more from this website, and your views are nice in support of new users.

  50. 50. minecraft games - 2019年9月4日 15:30

    Why viewers still make use of to read news papers when in this technological world the whole thing is existing on net?

  51. 51. quest bars cheap - 2019年9月7日 03:04

    Saved as a favorite, I like your web site!

  52. 52. minecraft games - 2019年9月18日 22:59

    Hi there! I know this is kinda off topic however I’d figured I’d ask.

    Would you be interested in trading links or maybe guest writing a blog article or vice-versa? My blog covers a lot of the same subjects as yours and I believe we could greatly benefit from each other.

    If you are interested feel free to shoot me an email. I look forward to hearing from you! Superb blog by the way!

  53. 53. quest bars cheap - 2019年10月8日 17:32

    Howdy I am so delighted I found your web site, I really found you by mistake, while I was browsing on Digg for something else, Anyways I am here now and would just like to say many thanks for a marvelous post and a all round exciting blog (I also love the theme/design), I don’t have time to look over it all at the minute but I have bookmarked it and also added your RSS feeds, so when I have time I will be back to read more, Please do keep up the fantastic b.

  54. 54. enterfuntech quest bars cheap - 2019年10月12日 05:38

    Wow that was strange. I just wrote an really long comment but after I clicked submit my comment didn’t appear. Grrrr… well I’m not writing all that over again. Regardless, just wanted to say great blog!

  55. 55. on coconut oil - 2019年11月13日 20:48

    It’s remarkable in favor of me to have a web page, which is beneficial in favor of my experience. thanks admin

  56. 56. coconut oil is - 2019年11月14日 09:55

    Its such as you read my thoughts! You appear to grasp a lot approximately this, such as you wrote the ebook in it or something. I think that you just could do with some percent to force the message home a bit, but other than that, this is excellent blog. A great read. I will definitely be back.

  57. 57. coconut oil for - 2019年11月14日 19:33

    It’s not my first time to pay a visit this site, i am visiting this web page dailly and obtain fastidious information from here daily.

  58. 58. plenty of fish dating site - 2019年11月17日 13:43

    you are actually a excellent webmaster. The site loading speed is incredible. It sort of feels that you’re doing any distinctive trick. Moreover, The contents are masterwork.

    you have performed a excellent task on this subject!

  59. 59. http://tinyurl.com/vprqsol - 2019年11月20日 02:28

    Remarkable issues here. I am very happy to peer your post. Thank you so much and I’m looking ahead to contact you. Will you please drop me a mail?

  60. 60. ps4 games - 2019年11月28日 05:50

    Attractive part of content. I just stumbled upon your weblog and in accession capital to claim that I get actually enjoyed account your blog posts. Anyway I will be subscribing on your feeds or even I success you get admission to persistently rapidly.

  61. 61. quest bars cheap - 2019年11月30日 13:29

    Simply desire to say your article is as astounding. The clarity in your post is just great and i could assume you are an expert on this subject.

    Well with your permission allow me to grab your RSS feed to keep up to date with forthcoming post. Thanks a million and please keep up the rewarding work.

  62. 62. quest bars cheap - 2019年12月1日 19:50

    I have been exploring for a bit for any high-quality articles or weblog posts in this sort of house . Exploring in Yahoo I ultimately stumbled upon this website. Studying this information So i’m happy to convey that I’ve an incredibly just right uncanny feeling I found out exactly what I needed. I so much certainly will make certain to don?t fail to remember this web site and give it a look regularly.

  63. 63. quest bars cheap coupon twitter - 2019年12月3日 02:26

    Very nice article. I certainly love this website. Thanks!

  64. 64. mobile legends zilong guide - 2019年12月4日 10:54

    I loved as much as you’ll receive carried out right here. The sketch is attractive, your authored material stylish. nonetheless, you command get bought an edginess over that you wish be delivering the following. unwell unquestionably come more formerly again since exactly the same nearly a lot often inside case you shield this hike.

  65. 65. quest bars cheap - 2019年12月8日 18:55

    Greate post. Keep posting such kind of information on your blog. Im really impressed by your site. Hello there, You’ve done an excellent job. I will certainly digg it and in my opinion suggest to my friends. I am sure they will be benefited from this site.

发表评论