Apocalypse Prevention
A significant number of religions and cults make some prediction about how the universe will end. The technical term for this is eschatology.
These are usually referred to as "apocalypse" events, particularly in the Abrahamic traditions. Other depictions of the end times in scripture include the Hindu god Kalki and Zoroastrian Frashokereti.
Scientific Eschatology
The wiki page "Ultimate fate of the universe" discusses the scientific theories that attempt to predict the manner and time in which the universe will end. This is the eschatology of science.
Fortunately all evidence indicates that this event is many billions of years of, and not something we need to concern our life choices with.
Apocalypse Allegories
In many cases, the notion of an apocalypse or rapture event is used as an allegory for war and the transformative changes in society that can arise from the ashes of the old.
Notions of a supernatural afterlife can make this a confusing metaphor. You could be talking about toppling the government of Rome, and literalists think you mean that angels are going to descend from the heavens any day now and start smiting people on your behalf.
The Apocalypse Is Bad
The apocalypse is bad. Don't look forward to the end of the world. Don't welcome the apocalypse with open arms. Don't make geopolitical decisions to help bring it about.
This stuff should be obvious, but therein lies the problem with a literalist view of the afterlife. For the literalist, everyone dying means everyone goes to heaven, except the people you don't like who go to hell. It turns what is actually the worst case scenario imaginable and re-casts it as the best case scenario.
In most cases, looking on the bright side of negative events is very good for promoting happiness. This is not the case when it comes to the apocalypse, whether you are using it as a metaphor for war and revolution, or talking about the actual end of existence.
Apocalypse Prevention
The philosophy and theology of metaculture accepts the eventual heat death of the universe will come, and until that time its practitioners should do anything in their power to avoid human extinction. This should come easily to evolved lifeforms.
If it should be possible to escape the end of this universe by creating or moving to another one, this option should be explored. However, it is premature to do so at this time.
In the interest of apocalypse prevention, issues like climate change and the proliferation of weapons of mass destruction should be considered high priorities. This is why the creation of a universal in-group is vitally important.