# How do you cancel the bare mass and the correction out? (Renormalisation)

#### Cedobor

mass experimental = m + c^2correction. How do you cancel the two out to get the physical mass?

#### Pmb

PHF Hall of Fame
mass experimental = m + c^2correction. How do you cancel the two out to get the physical mass?
As far as I know, the "physical mass" is the experimental mass. What do you think those terms mean. Knowing that can help me answer your question.

#### Cedobor

As far as I know, the "physical mass" is the experimental mass. What do you think those terms mean. Knowing that can help me answer your question.
Hi someone gave an analogy
"Let x = 4 + 1/r − 1/r
If you are going to assign a value to x at r=0, what would that value be? Does it matter that 1/r is infinite?" With the 4+1/r being the bare mass and the 1/r being the correction in this case would it matter if it's changed to x = 4 +1/w - 1/r where I've simply changed the letter representing a value?

#### Pmb

PHF Hall of Fame
Hi someone gave an analogy
"Let x = 4 + 1/r − 1/r
If you are going to assign a value to x at r=0, what would that value be? Does it matter that 1/r is infinite?" With the 4+1/r being the bare mass and the 1/r being the correction in this case would it matter if it's changed to x = 4 +1/w - 1/r where I've simply changed the letter representing a value?
x is undefined when y = 0. But you need to tell me what you're talking about, otherwise I can't help you.

You've stumbled upon one of the major problems in physics today.