- #1
jeebs
- 325
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sorry if this looks ugly but I couldn't find out how to write out bras and kets on the Latex thing.
I have these inner products
<f|g> = i<x|(AB - A<B> - <A>B + <A><B>)|x>
and
<g|f> = -i<x|(BA - B<A> - <B>A + <A><B>)|x>
where |x> is some arbitrary ket and A and B do not commute.
I'm trying to follow a derivation of the uncertainty principle that has a step which involves getting
<f|g> + <g|f> = i<x|[A,B]|x>,
but I'm not sure how to add the two things together.
I tried to see if it was allowed that, say, <x|M|x> + <x|N|x> = <x|(M+N)|x>, but that didn't work, and I tested this with a real numerical example so that definitely doesn't work. I need to somehow end up with
<f|g> + <g|f> = i<x|(AB - BA)|x>
but I haven't seen how objects like these add together before.
How is this done?
I have these inner products
<f|g> = i<x|(AB - A<B> - <A>B + <A><B>)|x>
and
<g|f> = -i<x|(BA - B<A> - <B>A + <A><B>)|x>
where |x> is some arbitrary ket and A and B do not commute.
I'm trying to follow a derivation of the uncertainty principle that has a step which involves getting
<f|g> + <g|f> = i<x|[A,B]|x>,
but I'm not sure how to add the two things together.
I tried to see if it was allowed that, say, <x|M|x> + <x|N|x> = <x|(M+N)|x>, but that didn't work, and I tested this with a real numerical example so that definitely doesn't work. I need to somehow end up with
<f|g> + <g|f> = i<x|(AB - BA)|x>
but I haven't seen how objects like these add together before.
How is this done?
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