While Sean Carroll’s latest chat-from-home presentations on his YouTube channel address the “biggest ideas” in the universe, other theoretical physicists explore whether our mind-boggling big universe has sort of a shelf life. A final reservation date, so to speak, at a fantastically socially-distanced restaurant at the end of the universe.
Reference: Forbes > “What Will It Be Like When We Reach The End Of The Universe?” by Ethan Siegel, Senior Contributor (May 6, 2020).
It’s remarkable how our understanding of the universe has changed over recorded history. Once viewed as so perfect and eternal – a timeless realm, the universe may in fact have an expiration date. But in what sense? And there’s no need to panic. Even the demise of life on Earth when the Sun becomes a red giant is likely one or two billion years away.
The Forbes article referenced above is a good overview of research regarding the fate of the universe, the various scenarios, and whether “heat death” remains the most likely projection. It includes some excellent visuals and contains a socially-distanced presentation (video) sponsored by the Perimeter Institute, as part of its reimagined lecture series, by astrophysicist Dr. Katie Mack, basically promoting her new book (a labor of love) The End of Everything: (Astrophysically Speaking) which will be released in August.
[Teaser] From one of the most dynamic rising stars in astrophysics, an accessible and eye-opening look at five ways the universe could end, and the mind-blowing lessons each scenario reveals about the most important concepts in cosmology.
… a mind-bending tour through five of the cosmos’s possible finales: the Big Crunch, Heat Death, the Big Rip, Vacuum Decay (the one that could happen at any moment!), and the Bounce.
YouTube > Perimeter Institute for Theoretical Physics > “A Conversation with Katie Mack” (May 6, 2020)
So, how does a mind-boggling cosmology connect with our search for meaning and purpose? A framework of such vast scales (10^-n – 10^n) with an end to the universe or to time itself – what does that do to us? Is this quest for cosmic specialness a timeless journey as well?
Well, that’s what physicist Brian Greene discusses in his new book Until the End of Time: Mind, Matter, and Our Search for Meaning in an Evolving Universe. Here’s a YouTube conversation about the book.
YouTube > Pioneer Works > “Until the End of Time: Brian Greene in Conversation with Janna Levin” (April 23, 2020).
Here’re some notes after watching the video.
A perspective on the journey toward an answer … highly reductionist but with synthesis [cf. Sean Carroll’s poetic naturalism]. Deeper understanding … scales of meaning … [book] The Denial of Death by Ernest Becker  … awareness of mortality, what does that do to us? Our lifespan and interplay with life cycle of universe, that physics explores an end to the universe.
We are the product of purposeless mindless laws of physics playing themselves out on our bags of particles. That perspectives changes the way we search for meaning and purpose. Manufacture our own meaning, coherence, make sense of existence. That doesn’t make it artificial but more noble, rather than accepting purpose thrust upon us from outer world. Doesn’t lead to darkness.
Re entropy, pockets of order – stars, so not total loss of structure. Entropic two-step. Big Bang as highly ordered start. Currently laws of physics do not define initial conditions, just the evolution from that. [Personally, I like the notion of evolution (from a Big Bang, for example) as the most efficient way to disperse energy across the universe.]
Challenge to explain life, consciousness. (Levin: A map of the external world evolving to a map of the internal world. A map because there’s just too much information.) Challenge of tethering that limited map to physical processes. (Levin: Free will debate.) Utterly spectacular that same laws for objects orchestrate consciousness (versus a magical impetus). A continuity. Of unfolding. A kind of freedom that distinguishes us from the inanimate world. Not freedom from laws of physics but a freedom in our range of behaviors.
A different kind of gratification than the notion of free will. A view of our role in the world. (Levin: Development of language and story telling.) About the mysteries that excite us, in different communities. Why we spend time doing that. A realm where people can make up (all kinds of) so so tales.
Some research that story telling prepares us for encounters in the real world. Safe rehearsals so to speak. [Cf. neuroscience.] And competition among those narratives. Visions of the world. The limits of language to describe some experiences. (Levin: And the dark side of arbitrary projections …) [Risks of imagination gone wild.]
(Levin: Myth and religion.) Being a spiritual person vs. a religious one. Religious journey of his older brother. (Levin: Paths to meaning.) A resonance between questions in each journey, physics and religion. [Cf. Two cultures redux.] (Levin: Survival value … adaptive role …) Utility of junk food as preying on past adaptive utility of energy rich foods in evolution. Music … we can highly value although predicated on primitive roles. Such as innovation. In physics new patterns of how the world works.
In book a metaphor for time scales that defy human intuition … logarithmic (powers of 10) floors in Empire State building. 10th floor as Big Bang to date. Floor 11 Sun goes red giant. … (Levin: A time when there can be no thought anymore.)
A reverence that we are here and what we can do [despite the dark side], our moment on the cosmic time line.
Q&A: Einstein’s block universe? Greene: That was a classical world. Determinism vs. probabilistic world. That’s not what we mean by free will. Not whether in classical or quantum world, but is the universe lawful? …
Space.com > “Four amazing astronomical discoveries from ancient Greece” by Gareth Dorrian, Ian Whittaker (May 10, 2020, originally published at The Conversation).
 Regarding Wiki’s article on heat death of the universe (aka Big Chill or Big Freeze), the Controversies section is interesting. Even the phrase “entropy of the universe” may not make sense. And I’ve always wondered how the universe could be considered a closed system in equilibrium. And how does gravity add to the mix?
Max Planck wrote that the phrase “entropy of the universe” has no meaning because it admits of no accurate definition. More recently, Walter Grandy writes: “It is rather presumptuous to speak of the entropy of a universe about which we still understand so little, and we wonder how one might define thermodynamic entropy for a universe and its major constituents that have never been in equilibrium in their entire existence.” According to Tisza: “If an isolated system is not in equilibrium, we cannot associate an entropy with it.” Buchdahl writes of “the entirely unjustifiable assumption that the universe can be treated as a closed thermodynamic system“.
 Amazon’s listing for Ernest Becker‘s book contains an excerpt. Here’s a quote from that excerpt.
It doesn’t matter whether the cultural hero-system is frankly magical, religious, and primitive or secular, scientific, and civilized. It is still a mythical hero-system in which people serve in order to earn a feeling of primary value, of cosmic specialness, of ultimate usefulness to creation, of unshakable meaning. They earn this feeling by carving out a place in nature, by building an edifice that reflects human value: a temple, a cathedral, a totem pole, a skyscraper, a family that spans three generations. The hope and belief is that the things that man creates in society are of lasting worth and meaning, that they outlive or outshine death and decay, that man and his products count. When Norman O. Brown said that Western society since Newton, no matter how scientific or secular it claims to be, is still as “religious” as any other, this is what he meant: “civilized” society is a hopeful belief and protest that science, money and goods make man count for more than any other animal. In this sense everything that man does is religious and heroic, and yet in danger of being fictitious and fallible.