Is Conjugate Symmetry Enough for a Hermitian Inner Product?

In summary, conjugate symmetry in an inner product implies antilinearity in the second slot, and together with linearity in the first slot, it also implies antilinearity in the first slot.
  • #1
Treadstone 71
275
0
I'm getting some confusing information from different sources. If an inner product satisfies conjugate symmetry, it is called Hermitian. But the definition of a hermitian inner product says it must be antilinear in the second slot only. Doesn't conjugate symmetry imply that it's antilinear in both slots?
 
Last edited:
Physics news on Phys.org
  • #2
Conjugate symmetry (plus linearity in the first slot) implies antilinearity in the second:

[tex]\langle u,\,\alpha v\rangle = \overline{\langle \alpha v,\, u\rangle } = \overline{\alpha \langle v,\, u\rangle } = \overline{\alpha}\overline{\langle v,\, u\rangle } = \overline{\alpha}\langle u,\, v\rangle[/tex]

If you think conjugate symmetry implies antilinearity in both, present a proof for it.
 
  • #3
I thought conjugate symmetry and antilinearity in the second slot implied antilinearity in the first, but I made an error when pulling out the constant.
 

What is a Hermitian Inner Product?

A Hermitian Inner Product is a mathematical operation that takes two vectors and produces a scalar value. It is similar to the dot product, but it is defined for complex vectors and has additional properties such as symmetry and linearity.

What are the properties of a Hermitian Inner Product?

A Hermitian Inner Product has three main properties: symmetry, linearity, and positive definiteness. Symmetry means that switching the order of the vectors does not change the result. Linearity means that the operation is distributive over addition and scalar multiplication. Positive definiteness means that the result is always a positive real number.

How is a Hermitian Inner Product calculated?

A Hermitian Inner Product is calculated by multiplying the complex conjugate of one vector with the other vector, and then taking the sum of the products. In mathematical notation, it is written as Hermitian Inner Product formula where u and v are complex vectors.

What is the significance of a Hermitian Inner Product in science?

A Hermitian Inner Product is important in many areas of science, particularly in quantum mechanics and signal processing. It allows for the calculation of distances between vectors, determination of orthogonality, and characterization of vector spaces. It is also used in various equations and principles, such as the Cauchy-Schwarz inequality and the Gram-Schmidt process.

What is the difference between a Hermitian Inner Product and a regular dot product?

The main difference between a Hermitian Inner Product and a regular dot product is the type of vectors that can be used. A dot product is defined for real vectors, while a Hermitian Inner Product is defined for complex vectors. Additionally, a Hermitian Inner Product has the added properties of symmetry and positive definiteness, which a dot product does not have. However, both operations share the property of linearity.

Similar threads

Replies
3
Views
2K
  • Linear and Abstract Algebra
Replies
2
Views
1K
  • Linear and Abstract Algebra
Replies
4
Views
2K
Replies
21
Views
1K
  • Quantum Physics
Replies
8
Views
2K
  • Quantum Physics
Replies
2
Views
926
  • Calculus and Beyond Homework Help
Replies
2
Views
2K
Replies
15
Views
2K
  • Quantum Physics
Replies
8
Views
2K
  • Linear and Abstract Algebra
Replies
2
Views
2K
Back
Top