The Doomsday algorithm is an algorithm for determining the day of the week for any calendar date. It is simple enough that, with practice, it can be done mentally without paper or pencil. Just like in part 1 of this paper, we would like to suggest a modification to the calculation of the doomsyear component of the Doomsday algorithm. We call this proposed method the Odd+11 method. For compariso...

We analyze the arguments allegedly supporting the so-called Self-Indication Assumption (SIA), as an attempt to reject counterintuitive consequences of the Doomsday Argument of Carter, Leslie, Gott and others. Several arguments purportedly supporting this assumption are demonstrated to be either flawed or, at best, inconclusive. Therefore, no compelling reason for accepting SIA exists so far, an...

We make corrections on the paper by González-D ´ iaz [Phys. Lett. B 586 (2004) 1] where the false illustration of Eq. (10) for the case of β = 0.5 (relevant to Fig. 1 (II) therein is pointed out and illustrated.

If the human race comes to an end relatively shortly, then we have been born at a fairly typical time in history of humanity. On the other hand, if humanity lasts for much longer and trillions of people eventually exist, then we have been born in the first surprisingly tiny fraction of all people. According to the Doomsday Argument of Carter, Leslie, Gott, and Nielsen, this means that the chanc...

Recent developments in cosmology indicate that every history having a nonzero probability is realized in infinitely many distinct regions of spacetime. Thus, it appears that the universe contains infinitely many civilizations exactly like our own, as well as infinitely many civilizations that differ from our own in any way permitted by physical laws. We explore the implications of this conclusi...