Space in Regular Expression

Best approach is to create a method in js file using jquery to create space in regular expression

$.validator.addMethod("alpha",
            function (value, element) {
                var alphaRegExp = new RegExp("^[\\sa-zA-Z]*$");
                if (alphaRegExp.test(element.value)) {
                    return true;
                }
                else return false;
            },
            "Please enter alphabet"
    );