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documentation:guide:overview_of_hep_features [2015/09/22 18:28] 127.0.0.1 external edit |
documentation:guide:overview_of_hep_features [2015/11/21 11:02] poslavskysv [Dirac & SU(N) algebra] |
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</sxh> | </sxh> | ||
See [[documentation:ref:DiracTrace]]. | See [[documentation:ref:DiracTrace]]. | ||
+ | |||
+ | ---- | ||
+ | ===SpinorsSimplify=== | ||
+ | simplifies Dirac spinors: | ||
+ | <sxh groovy; gutter: false> | ||
+ | defineMatrices 'G_a', 'G5', Matrix1.matrix, 'cu', Matrix1.covector | ||
+ | def sSimplify = SpinorsSimplify[[uBar: 'cu', Momentum: 'p_a', Mass: 'm']] | ||
+ | println sSimplify >> 'cu*G^a*p_a'.t | ||
+ | </sxh> | ||
+ | <sxh plain; gutter: false> | ||
+ | > -m*cu*G_{b}+2*cu*p_{b} | ||
+ | </sxh> | ||
+ | See [[documentation:ref:SpinorsSimplify]]. | ||
+ | |||
+ | ---- | ||
+ | ===DiracSimplify=== | ||
+ | simplifies products of gamma matrices: | ||
+ | <sxh groovy; gutter: false> | ||
+ | defineMatrices 'G_a', 'G5', Matrix1.matrix | ||
+ | println DiracSimplify >> 'G5*G_a*G5*G_b*G^a*G^b'.t | ||
+ | </sxh> | ||
+ | <sxh plain; gutter: false> | ||
+ | > -8 | ||
+ | </sxh> | ||
+ | See [[documentation:ref:DiracSimpllify]]. | ||
+ | |||
+ | ---- | ||
+ | ===DiracOrder=== | ||
+ | order products of gamma matrices: | ||
+ | <sxh groovy; gutter: false> | ||
+ | defineMatrices 'G_a', 'G5', Matrix1.matrix | ||
+ | println DiracOrder >> 'G5*G_c*G_b*G_a'.t | ||
+ | </sxh> | ||
+ | <sxh plain; gutter: false> | ||
+ | > G_{a}*G_{b}*G_{c}*G5+2*G_{b}*G5*g_{ca}-2*G_{c}*G5*g_{ba}-2*G_{a}*G5*g_{cb} | ||
+ | </sxh> | ||
+ | See [[documentation:ref:DiracOrder]]. | ||
---- | ---- | ||
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</sxh> | </sxh> | ||
See [[documentation:ref:setMandelstam]]. | See [[documentation:ref:setMandelstam]]. | ||
+ | |||
+ | ---- | ||
+ | ===setMandelstam5=== | ||
+ | generates a list of mass shell and general Mandelstam substitutions for 2->3 processes: | ||
+ | <sxh groovy; gutter: false> | ||
+ | def mandelstam = | ||
+ | setMandelstam5([k1_a: 'm1', k2_a: 'm2', k3_a: 'm3', k4_a: 'm4', k5_a: 'm5']) | ||
+ | println mandelstam >> 'k1_a*k2^a + k3_b*k1^b + k5_a*k1^a'.t | ||
+ | </sxh> | ||
+ | <sxh plain; gutter: false> | ||
+ | > (1/2)*(s-m2**2-m1**2)+(1/2)*(-t1+m3**2+m1**2)+(1/2)*(s+t1-m4**2-m2**2-m3**2+t2-m1**2) | ||
+ | </sxh> | ||
+ | See [[documentation:ref:setMandelstam5]]. | ||
---- | ---- | ||
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* [[documentation:tutorials:compton_scattering_in_qcd]] | * [[documentation:tutorials:compton_scattering_in_qcd]] | ||
* [[documentation:tutorials:b_c_to_u_bar_d_gamma|$B_c \to u \bar d \gamma$]] | * [[documentation:tutorials:b_c_to_u_bar_d_gamma|$B_c \to u \bar d \gamma$]] | ||
- | |||
====See also==== | ====See also==== | ||
* Related guides: [[documentation:guide:list_of_transformations]], [[documentation:guide:calculating_one-loop_counterterms]], [[documentation:guide:programming_with_redberry]] | * Related guides: [[documentation:guide:list_of_transformations]], [[documentation:guide:calculating_one-loop_counterterms]], [[documentation:guide:programming_with_redberry]] | ||