Complex scalar fields and antiparticles in quantization

[captain]

I wanted to ask a quick question about the complex scalar field. My question is that does the scalar field need to be complex in order to include the part for anti-particles or do you regards the scalar field for particles and anti-particles separate. I saw this specifically when you second quantization to quantize the scalar field that satisfies the Klein-Gordon equation. Are there any advantages and disadvantages of making the scalar field complex if it really doesn't apply to what I mentioned above? Thanks in advance for anybody who can clarify this question.

 

[Ben Niehoff]

If the field is real, then the particle is its own antiparticle. Note that a real KG field is uncharged.

So, one uses complex KG fields to model spin-0, charged particles, such as the charged pions. (The neutral pion is modeled using a real KG field).

 

[akhmeteli]

If the field is real, then the particle is its own antiparticle. Note that a real KG field is uncharged.

Not necessarily, according to Shroedinger (Nature (1952), v.169, p.538). I mentioned this article in several posts.