Is this a “good enough” statement of Wigner's theorem from Quantum Mechanics?












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I'm a fourth year physics and math student who is writing up a report on some quantum mechanical symmetries and their consequences. The "audience" for my paper are either senior physics majors or first year graduate students in physics. Wigner's theorem's mathematical content is unfortunately beyond the scope of my report so I decided to "water it down". My question is this: is this an acceptably simplified version of Wigner's theorem?



Theorem (Wigner)
Let $Psi, Phi$ be arbitrary state vectors in a Hilbert space $mathscr{H}$. Suppose $delta: mathscr{H} mapsto mathscr{H}$ is bijective and Wigner symmetric (that is, under the mapping $delta$, the transition probability $langle Psi | Phi rangle$ is unchanged). Then




  1. there exists a unitary or anti-unitary operator $U$ such that
    $$delta(psi) = U psi U^{-1},$$


  2. $U$ is unique up to an arbitrary phase factor.


Is there anything I'm misunderstanding with this formulation of Wigner's theorem?










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  • 1




    $begingroup$
    Cross-posted to Physics.
    $endgroup$
    – rob
    Dec 9 '18 at 22:23
















0












$begingroup$


I'm a fourth year physics and math student who is writing up a report on some quantum mechanical symmetries and their consequences. The "audience" for my paper are either senior physics majors or first year graduate students in physics. Wigner's theorem's mathematical content is unfortunately beyond the scope of my report so I decided to "water it down". My question is this: is this an acceptably simplified version of Wigner's theorem?



Theorem (Wigner)
Let $Psi, Phi$ be arbitrary state vectors in a Hilbert space $mathscr{H}$. Suppose $delta: mathscr{H} mapsto mathscr{H}$ is bijective and Wigner symmetric (that is, under the mapping $delta$, the transition probability $langle Psi | Phi rangle$ is unchanged). Then




  1. there exists a unitary or anti-unitary operator $U$ such that
    $$delta(psi) = U psi U^{-1},$$


  2. $U$ is unique up to an arbitrary phase factor.


Is there anything I'm misunderstanding with this formulation of Wigner's theorem?










share|cite|improve this question









$endgroup$








  • 1




    $begingroup$
    Cross-posted to Physics.
    $endgroup$
    – rob
    Dec 9 '18 at 22:23














0












0








0





$begingroup$


I'm a fourth year physics and math student who is writing up a report on some quantum mechanical symmetries and their consequences. The "audience" for my paper are either senior physics majors or first year graduate students in physics. Wigner's theorem's mathematical content is unfortunately beyond the scope of my report so I decided to "water it down". My question is this: is this an acceptably simplified version of Wigner's theorem?



Theorem (Wigner)
Let $Psi, Phi$ be arbitrary state vectors in a Hilbert space $mathscr{H}$. Suppose $delta: mathscr{H} mapsto mathscr{H}$ is bijective and Wigner symmetric (that is, under the mapping $delta$, the transition probability $langle Psi | Phi rangle$ is unchanged). Then




  1. there exists a unitary or anti-unitary operator $U$ such that
    $$delta(psi) = U psi U^{-1},$$


  2. $U$ is unique up to an arbitrary phase factor.


Is there anything I'm misunderstanding with this formulation of Wigner's theorem?










share|cite|improve this question









$endgroup$




I'm a fourth year physics and math student who is writing up a report on some quantum mechanical symmetries and their consequences. The "audience" for my paper are either senior physics majors or first year graduate students in physics. Wigner's theorem's mathematical content is unfortunately beyond the scope of my report so I decided to "water it down". My question is this: is this an acceptably simplified version of Wigner's theorem?



Theorem (Wigner)
Let $Psi, Phi$ be arbitrary state vectors in a Hilbert space $mathscr{H}$. Suppose $delta: mathscr{H} mapsto mathscr{H}$ is bijective and Wigner symmetric (that is, under the mapping $delta$, the transition probability $langle Psi | Phi rangle$ is unchanged). Then




  1. there exists a unitary or anti-unitary operator $U$ such that
    $$delta(psi) = U psi U^{-1},$$


  2. $U$ is unique up to an arbitrary phase factor.


Is there anything I'm misunderstanding with this formulation of Wigner's theorem?







mathematical-physics quantum-mechanics






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asked Dec 6 '18 at 22:19









talrefaetalrefae

446




446








  • 1




    $begingroup$
    Cross-posted to Physics.
    $endgroup$
    – rob
    Dec 9 '18 at 22:23














  • 1




    $begingroup$
    Cross-posted to Physics.
    $endgroup$
    – rob
    Dec 9 '18 at 22:23








1




1




$begingroup$
Cross-posted to Physics.
$endgroup$
– rob
Dec 9 '18 at 22:23




$begingroup$
Cross-posted to Physics.
$endgroup$
– rob
Dec 9 '18 at 22:23










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