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View Full Version : Are Higgs bosons really necessary?


very_cryptic@hotmail.com
Aug26-04, 04:32 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=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>In the original Higgs model, we have the electroweak [SU(2) X U(1)]/Z_2\nYang-Mills theory and a Higgs field which takes values in a (linear)\ndoublet representation of the gauge group which then acquires a VEV. In\nthis model, the mass spectrum includes massive W and Z bosons and a\nmassless photon (which we observe) and a Higgs boson (which we haven\'t\nobserved yet).\n\nHowever, there is no rule in quantum field theory telling us scalar\nfields have to come in linear representations. A nonlinear sigma model\nis also possible provided it\'s a realization of the gauge group. So,\nwhy can\'t we take the Higgs field to be a nonlinear sigma model taking\nvalues in the coset space {[SU(2) X U(1)]/Z_2}/U(1)_em ? This model\nwould still predict the right spin-1 spectrum but in addition, there\nwouldn\'t be any Higgs boson in the msss spectrum, which is consistent\nwith current observations.\n\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">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>In the original Higgs model, we have the electroweak [SU(2) X U(1)]/Z_2
Yang-Mills theory and a Higgs field which takes values in a (linear)
doublet representation of the gauge group which then acquires a VEV. In
this model, the mass spectrum includes massive W and Z bosons and a
massless photon (which we observe) and a Higgs boson (which we haven't
observed yet).

However, there is no rule in quantum field theory telling us scalar
fields have to come in linear representations. A nonlinear \sigma model
is also possible provided it's a realization of the gauge group. So,
why can't we take the Higgs field to be a nonlinear \sigma model taking
values in the coset space {[SU(2) X U(1)]/Z_2}/U(1)_em ? This model
would still predict the right spin-1 spectrum but in addition, there
wouldn't be any Higgs boson in the msss spectrum, which is consistent
with current observations.

kurious
Sep4-04, 02:05 AM
very-cryptic:
>"Are higgs bosons really necessary?"

Kurious:
Any field that opposes a change in motion of a particle could
"cause" its mass.And that field could result from a new property of matter (just as colour was once a new property) .The Higgs is popular because it restores symmetries to other fields in the standard model.But the standard model doesn't include gravity
and when you think how important the concept of mass is to gravitational theory
this seems peculiar.