Noether theorem [Archive] - Physics Forums

Alexander Kubelsky

Apr7-04, 08:46 AM

Danny Ross Lunsford

Apr7-04, 09:05 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resize=yes,status=no,wi dth=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\nAlexander Kubelsky wrote:\n\n\\> Can anyone think of classical field theory without Noether theorem ?\n\\> And can we talk about existence of field theory before Noether theorem ?\n\\> S.Wienberg point 1927 as the birth date of field theory, correlate with Dirac works.\n\nIMO too much is made of this topic and a more or less simple result is\nmade to seem mysterious. The answer is, to the extent a part of physics\nis expressible by a variational principle, then the ideas of Noether\nwill be important. Every real field theory I know of is expressible that\nway.\n\nField theory proper began equally with Dirac, Jordan, and Pauli. The\npapers are\n\nDirac, Proc. Roy. Soc. London A, 114 (1927) p.243, 710\nJordan and Pauli, Zeits. f. Physik 47 (1928) p. 151\n\nThe formulation of quantum electrodynamics followed in three papers from\n1929-1931:\n\nPauli and Heisenberg, Zeits. f. Physik 56 (1929) p. 1\nPauli and Heisenberg, Zeits. f. Physik 59 (1930) p. 169\nFermi, Rev. Mod. Phys. 4 (1931) p. 131\n\nThe positron was then discovered in the lab and it\'s been all downhill\nsince :)\n\nPascual Jordan is an interesting case. He was certainly on the same\nlevel as the other famous inventers of quantum theory, but got mixed up\nin German politics and was besmirched with Naziism (in his case there is\nno plausible deniability, as with Heisenberg). Today he is a forgotten name.\n\n-drl\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>Alexander Kubelsky wrote:

> Can anyone think of classical field theory without Noether theorem ?
> And can we talk about existence of field theory before Noether theorem ?
> S.Wienberg point 1927 as the birth date of field theory, correlate with Dirac works.

IMO too much is made of this topic and a more or less simple result is
made to seem mysterious. The answer is, to the extent a part of physics
is expressible by a variational principle, then the ideas of Noether
will be important. Every real field theory I know of is expressible that
way.

Field theory proper began equally with Dirac, Jordan, and Pauli. The
papers are

Dirac, Proc. Roy. Soc. London A, 114 (1927) p.243, 710
Jordan and Pauli, Zeits. f. Physik 47 (1928) p. 151

The formulation of quantum electrodynamics followed in three papers from
1929-1931:

Pauli and Heisenberg, Zeits. f. Physik 56 (1929) p. 1
Pauli and Heisenberg, Zeits. f. Physik 59 (1930) p. 169
Fermi, Rev. Mod. Phys. 4 (1931) p. 131

The positron was then discovered in the lab and it's been all downhill
since :)

Pascual Jordan is an interesting case. He was certainly on the same
level as the other famous inventers of quantum theory, but got mixed up
in German politics and was besmirched with Naziism (in his case there is
no plausible deniability, as with Heisenberg). Today he is a forgotten name.

-drl