著名的动量能量公式在数学上是恒等式

---从0=0导出动量-能量关系的数学表达式

 

冯向军

 

 

摘要

 

从0=0推导出著名的动量能量关系式的数学表达式,从而证明了该关系式在数学上是恒等式。

 

关键词:恒等式,动量-能量关系式。

 

 

一、推导

 

我们暂抛开一切符号的物理意义来作纯数学推导

 

因为 0 = 0                                                              (1)

令:0<=v < c

有:

1/(1-(v/c)2) = 1/(1-(v/c)2)                                              (2)

考虑到:

 

1/(1-(v/c)2) = 1 + (v/c)2 / (1-(v/c)2)                                    (3)

 

有 (m02c4)/(1-(v/c)2) = m02c4 + (m0/sqrt (1-(v/c)2)vc)2                     (4)

 

m = m0/sqrt(1-(v/c)2)                                                    (5)

E=mc2                                                                    (6)

p=mv                                                                    (7)

E2 = (m0c2)2 + (pc)2                                                      (8)

 

( 8 )式就是动量-能量关系的数学表达式!

 

 

二、结论

 

狭义相对论中著名的动量-能量关系式[1] 在数学上是恒等式。

 

 

参考文献

[1] Special relativity, Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/Special_relativity