Yes, the two expressions are equivalent.

Thread starter v_pino
Start date Feb 1, 2012
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Complex

AI Thread Summary

The discussion centers on whether the expressions P_x = c_+^* c_- + c_-^* c_+ and 2Re(c_+^* c_-) are equivalent. It is noted that the equivalence depends on the relationship between c_- and c_+. Specifically, if c_-·c_+ equals (c_+^*·c_-)*, then the expressions can be transformed using the property that c + c^* = 2Re(c). The conversation emphasizes the importance of understanding complex conjugates in this context. Ultimately, the equivalence hinges on the specific values of c_+ and c_-.

Feb 1, 2012

v_pino

Homework Statement

I'm part way through a problem and got the answer P_x=c_+^* c_-+c_-^*c_+.
But the answer should be 2Re(c+^*c_-).

Are the two equivalent?

Homework Equations

c+c^*=2Re(c)

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Feb 2, 2012

Redbelly98

Staff Emeritus

Science Advisor

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v_pino said:

Are the two equivalent?

That depends. Is c_-*·c₊ equal to (c₊*·c_-)* ? If so, then you can apply:

Homework Equations

c+c^*=2Re(c)

Feb 2, 2012

conquest

Just complex conjugate on of the both terms

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