Recently, there is some speculation about the fact that quantum gravity could imply the existence (naturally, even without extra dimensions or any other stuff) of 3 gravitons: a massive spin-2 ghost and a massive graviscalar field.
1st. Why does the massive spin-2 GHOST make sense? Is it not cumbersome a PHYSICAL ghost with spin-2?
2nd. The additional massive scalar field, is correct to call it a graviscalar?