Add as show below

<field name="name" required=True />

and then convert to this as a answer......thanx

To make a field required, you can achieve by 2 methods:

1. WITH PY:
    _columns = {
      'name': fields.char("Name",size=64,required=1),
    }

2. WITH XML: (Same as Jeff's Suggestion)
         <field name="name" required="1"/>

NOTE: If we make the field required at PYTHON file, no need to add required at XML.

Error: Unknown field id in domain [["id","!=",false]]:
          A domain can be set for the fields that are displayed on its own view.

If you are trying to use domain = "[('categ_id','=',False)]", then 'categ_id' field should be available in their respective FORM/TREE view.