Alexander is the author of a book entitled Dark Dominion, in which he explored the idea that another world occupied the same spacetime as our own.
ˌælɪɡzˈændɚɹ ɪz ðɪ ˈɔːθɚɹ əvə bˈʊk ɛntˈaɪɾəld dˈɑːɹk dəmˈɪniən, ɪnwˌɪtʃ hiː ɛksplˈoːɹd ðɪ aɪdˈiə ðæt ɐnˈʌðɚ wˈɜːld ˈɑːkjʊpˌaɪd ðə sˈeɪm spˈeɪstaɪm æz ˌaʊɚɹ ˈoʊn.