This all depends on what you mean by a "spiritual experience". If you mean the feeling of awe you get from contemplating the majesty of nature, the vastness of the universe, or similar, then maybe. But probably not, because none of these things mean that "spirituality" (again, depending on what you mean by that word) is real. If by "spiritual experience" you mean some experience of a greater power (call it "god" if you like), then no, that is almost certainly your mind at work.