liuyanghe:和原文好象有出入

根據下麵你所提供的參考文獻的兩段文章，你說的“龐加萊在100多年前看到的小漏洞”可能就是龐加萊所說的“位移電流理論的一個缺點”。龐加萊沒說過：“...位移電流...可以推動自由電子運動，使電子獲得能量，但是反過來，運動的電子...不能對位移電流有任何影響，....於是能量就不守恒了。”
http://www.hitesla.org/ShowPost.asp?ThreadID=444

值得指出，雖然 Maxwell 用位移電流概念成功地解釋了電容器電路中的電流連續性的問題，並預言了電磁波的存在，但他錯誤地把電磁位的瞬時解（Instantaneous vector potential）作為電磁場以無窮大速度傳播的理論依據，以致位移電流概念受到質疑。

謝謝你提供的參考文獻。
---------------------------------------------------------------
Lorentz himself, whowas very familiar with Poincar´e’s publications and who used retarded potentials from 1902 in his theory, stated pointedly in 1906 that ‘an electromagnetic field in the ether is never produced by any other causes than the presence and motion of electrons’. In Lorentz theory all fields—bound electric and magnetic and free radiation fields—are generated by charges: contrary to J J Thomson, changing electric fields do not generate magnetic fields. （意思：勞倫茲認為電磁場隻能由電荷產生，改變電場不能產生磁場。）

In 1901 Poincar´e found another weakness in displacement current theory. He showed that when the displacement current is acted on by a magnetic field it ‘does not experience any mechanical action according to the theory of Lorentz’. Although the displacement current neither produces a magnetic field nor is affected by a magnetic field in Lorentz electromagnetism, it remained a physical reality for both Poincar´e and Lorentz as a process in the ether equivalent to light and as contributing to the closure of currents in an open circuit. （意思：按勞倫茲理論，龐加萊發現位移電流理論的另一個缺點：位移電流不產生磁場，位移電流和生磁場之間沒有互作用。）

John Roche,“The present status of Maxwell's displacement current,” Eur. J. Phys. 19,155 (1998). http://128.112.100.2/~kirkmcd/examples/EM/roche_ejp_19_155_98.pdf

所有跟帖： 

• 是你理解錯誤 -liuyanghe- ♂ (228 bytes) () 05/26/2010 postreply 15:50:58

• 看看你的答複： -zhejiangbeijing- ♂ (545 bytes) () 05/26/2010 postreply 16:31:23

• 說你看不懂，還不信！ -liuyanghe- ♂ (0 bytes) () 05/26/2010 postreply 17:39:03

• 龐加萊提出過"位移電流破壞動量守恒”？ -zhejiangbeijing- ♂ (229 bytes) () 05/26/2010 postreply 16:49:36

• 知道什麽是動量嗎？ -liuyanghe- ♂ (0 bytes) () 05/26/2010 postreply 17:36:40

• 你家裏的微波爐能加熱食品嗎？ -zhejiangbeijing- ♂ (305 bytes) () 05/26/2010 postreply 17:07:28

• 不懂裝懂，抬杠 -liuyanghe- ♂ (0 bytes) () 05/26/2010 postreply 17:35:16

• 信號源是有線還是無線發送能量？ -zhejiangbeijing- ♂ (356 bytes) () 05/27/2010 postreply 01:53:23