- #1
venus_in_furs
- 19
- 1
ok so this is a bit of a boring question, so sorry in advance, but for some reason I am struggling with this.
I am deriving the seesaw formula.
Now I have gone through the derivivate and I get A : ## m_{\nu} = - m_D^T M^{-1} m_D ##
Now I have seen other derivations where they get B : ## m_{\nu} = - m_D M^{-1} m_D^T ##
Note( transpose on LH or RH side )
So I think the reason for this is that in the langrangian you always have + h.c.
And so depending on which term you write, and which term you shove in h.c. I think you get these two different versions.
But essentially it must be describing the same physics, obviously.
Now, in a paper I am reading they have version B and they have the diagonalisation
##-Dm = U^{\dagger} m_{\nu} U^* = U^{\dagger} m_D M^{-1} m_D^T U^* ##
They have used B. I need some somehow reconcile A with B and I am a bit confused.
## D_m ## should be the same whatever convension, its real and diagonal, so it is just mass eingenvalues on the diagonal of the mass matrix.
but it doesn't seem obvious that ## U^{\dagger} m_D M^{-1} m_D^T U^* = U^{\dagger} m_D^T M^{-1} m_D U^* ## ? these don't look equal ..
but it must do, if both give a diagonal matrix of mass values?
is this right? Or have I missed something?Basically I have written deriviation A in my report. but now I realize some work I did used deriviation B. So I need some smooth transition between the two.
I hope this makes sense, and apologies again for such a boring convension based question, but I guess it means I'm lacking some fundamental understanding if I am struggling with this.
Thanks
I am deriving the seesaw formula.
Now I have gone through the derivivate and I get A : ## m_{\nu} = - m_D^T M^{-1} m_D ##
Now I have seen other derivations where they get B : ## m_{\nu} = - m_D M^{-1} m_D^T ##
Note( transpose on LH or RH side )
So I think the reason for this is that in the langrangian you always have + h.c.
And so depending on which term you write, and which term you shove in h.c. I think you get these two different versions.
But essentially it must be describing the same physics, obviously.
Now, in a paper I am reading they have version B and they have the diagonalisation
##-Dm = U^{\dagger} m_{\nu} U^* = U^{\dagger} m_D M^{-1} m_D^T U^* ##
They have used B. I need some somehow reconcile A with B and I am a bit confused.
## D_m ## should be the same whatever convension, its real and diagonal, so it is just mass eingenvalues on the diagonal of the mass matrix.
but it doesn't seem obvious that ## U^{\dagger} m_D M^{-1} m_D^T U^* = U^{\dagger} m_D^T M^{-1} m_D U^* ## ? these don't look equal ..
but it must do, if both give a diagonal matrix of mass values?
is this right? Or have I missed something?Basically I have written deriviation A in my report. but now I realize some work I did used deriviation B. So I need some smooth transition between the two.
I hope this makes sense, and apologies again for such a boring convension based question, but I guess it means I'm lacking some fundamental understanding if I am struggling with this.
Thanks