Why can't an abstract method be synchronized?

Question

I was reading a thread from CodeRanch saying that abstract methods could not be synchronized due to the fact that an abstract class cannot be instantiated, meaning no object

Answer 1

synchronized void foo()
{
    body
}

is defined to be equivalent to

void foo()
{ 
    synchronized(this)
    {
        body
    }
}

(if static, synchronized on the class instead of this)

Since an abstract method has no body, synchronized keyword on the method is undefined.