Just Finished Reading The End of Everything (Astrophysically Speaking) by Katie Mack

Katie Mack is an astrophysicist/cosmologist who also is one of those treasured scientists who strive to popularize their respective fields and increase awareness and understanding among the general population...I love people like that...Neil deGrasse Tyson and the late Carl Sagan and Isaac Asimov also come to mind.  I read Tyson's book Astrophysics For People in a Hurry three years ago and loved it: here's a link to my earlier article about it: [Tyson].  Mack's just recently published book The End of Everything (Astrophysically Speaking) picks up where Tyson left off and is an intriguing adventure into the origins, fundamental nature...and possible endings...of our universe as today's astrophysicists, including the author, are on the cutting edge of discovery.  She is a bit more detailed on the scientific side with her narrative than was Tyson in his book, but I recognize that it's got to be tough translating what is essentially highly technical material bathed in complex mathematics into common language that laypeople can understand.  You get treated to a great variety of topics: stages in the universe's development, quantum theory, the different fundamental forces, general relativity, entropy, the cosmic microwave background, inflation, gravity fields, subatomic physics...this plus much more. Since the book's title referred to the end of everything, Mack's presentation culminates in a listing and description of five potential scenarios:

The Big Crunch...the amount of matter in the universe ultimately causes an end to its expansion and causes it to draw back upon itself and contract.

The Heat Death...with dark energy now a recognized element in the cosmos and causing an accelerating...no slowing...expansion, this scenario has the cosmos reaching a point of complete cooling where entropy has reached its limit and time itself ceases.

The Big Rip...another dark energy-caused scenario whereby the very fabric of existence is torn apart suddenly and without warning.

Vacuum Decay...what we nowadays consider as an absolute vacuum is actually permeated with a gravity field...should that field alter into a higher vacuum state anywhere in the universe the result could be the Bubble of Death expanding to end and replace our own reality.

Multiverse Collison...in a setting comprised of multiple universes, another one colliding with us could conceivably cause our destruction...assuming of course that there are actually other universes.

When I refer to "our" destruction, I'm referring to our cosmos as a whole and not specifically our own Earth and its life, doomed to disappear in a few billion years anyway as the dying sun expands as a red giant and encompasses our orbit.  I noticed something interesting about Katie Mack's presentation: the doomsday scenarios...particularly that one about vacuum decay...seem to exist as logical extensions of ongoing theories, theories that are subject to revision with incoming new information.  As for the universe's actual, ultimate demise, this sounds like a topic that's a little bigger than me.  It's clear to me that Katie Mack loves her job...I liked her book so much that I bought it!