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Nikolaas Van der Heyden
Jul22-04, 05:17 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>\nIn QFT-textbooks, the process of dynamical mass-generation is often used.\nFor example one gets an effective quarkmass as a solution of the Schwinger\nDysonequation. This mass is dependent on the quarks momentum.\n\n\n\nThe effective quarkmass as a function of the momentum gives an image of the\ninteraction between a quark and its surrounding virtual particles. For\nlow-energy quarks, the strong force coupling constant is very large because\nof asymptotic freedom. So in this condition, many virtual particles become\nreal because of the strong interaction and thus quarkmass is generated.\n\n\n\nIs this conclusion right or am I making e few mistakes here?\n\n\n\nCan anyone give me a clear definition of the effective quarkmass, what does\nis really mean?\n\nHow is mass generated dynamically\n\n\n\n\n\nThanks a lot\n\n\n\nNikolaas Van der Heyden\n\n\n\nNikolaas.vanderheyden@ugent.be\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 QFT-textbooks, the process of dynamical mass-generation is often used.
For example one gets an effective quarkmass as a solution of the Schwinger
Dysonequation. This mass is dependent on the quarks momentum.



The effective quarkmass as a function of the momentum gives an image of the
interaction between a quark and its surrounding virtual particles. For
low-energy quarks, the strong force coupling constant is very large because
of asymptotic freedom. So in this condition, many virtual particles become
real because of the strong interaction and thus quarkmass is generated.



Is this conclusion right or am I making e few mistakes here?



Can anyone give me a clear definition of the effective quarkmass, what does
is really mean?

How is mass generated dynamically





Thanks a lot



Nikolaas Van der Heyden



Nikolaas.vanderheyden@ugent.be
alistair
Jul22-04, 01:07 PM
<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>\n\n\n\n&gt; Nikolaas Van der Hayden said:\n&gt; &gt;the strong force coupling constant is very large\n\nAlistair asks:\nIs this because NF ( number of quarks in pair production) is large in\nthe equation below:\n\na(E)= 12 pi / {(33 - 2NF) ln [E^2 / LAMBDA^2]}\n\nwhere alpha (E) is the strong coupling constant,\nE is the energy of virtual particles and lambda is an\nexperimentally determined constant.\nWas this equation predicted by theory or derived\nfrom experimental observations?\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>Nikolaas Van der Hayden said:
> >the strong force coupling constant is very large

Alistair asks:
Is this because NF ( number of quarks in pair production) is large in
the equation below:

a(E)= 12 \pi / {(33 -[/itex] 2NF) [itex]ln [E^2 / \LAMBDA^2]}

where \alpha (E) is the strong coupling constant,
E is the energy of virtual particles and \lambda is an
experimentally determined constant.
Was this equation predicted by theory or derived
from experimental observations?