Some writers immerse us so deeply in time that present-day issues are dwarfed by immensity. I always think of Olaf Stapledon and Star Maker (1937) in this regard, but consider Arthur C. Clarke’s The City and the Stars (1956), in which we see the city Diaspar on the Earth of a billion years from now. And even Clarke’s story is trumped by Greg Bear, whose City at the End of Time (2008), something of an homage not just to Clarke but to William Hope Hodgson as well, takes us to the Kalpa, a place and a civilization that is trying to ward off the breakdown of physical laws one hundred trillion years hence.
With the Bear novel we enter the realm of extreme cosmology. Here spacetime itself is threatened by an entity intent on destroying it, creating a Chaos that harks back to ancient Earth myth. The human race is scattered across the cosmos, the galaxies themselves burned out husks. I also mentioned Hodgson above. The English writer (1877-1918), who would die at Ypres, produced a vast novel called The Night Land (1912) that explores a universe where the Sun has gone dark. Clark Ashton Smith, who loved purple prose and wrote his share of it, would call Hodgson’s work “…the ultimate saga of a perishing cosmos, the last epic of a world beleaguered by eternal night and by the unvisageable [sic] spawn of darkness.”
I’m drawn back to these tales today because of work out of the Galaxy and Mass Assembly (GAMA) project, an effort that itself pushes right up against the ultimate fate of the cosmos. GAMA is a multi-wavelength survey using both ground- and space-based telescopes to measure the energy output of over 200,000 galaxies. Presented at the International Astronomical Union’s 29th General Assembly in Honolulu, the results tell us that the energy produced in a section of the universe today is only half what it was two billion years ago.
A ‘world beleaguered by eternal night indeed.’ The fading, as we may conceive it, is occurring across all wavelengths from the ultraviolet to the far infrared. This is not, as it turns out, startling news, for we’ve been tracking the accelerating expansion of the universe since the late 1990s, when so-called ‘dark energy’ was invoked to explain the phenomenon. Simon Driver (University of Western Australia), who heads up the GAMA team, puts the matter rather charmingly: “The Universe will decline from here on in, sliding gently into old age. The Universe has basically sat down on the sofa, pulled up a blanket and is about to nod off for an eternal doze.”
Image: The first data from the GAMA survey examine over 200,000 galaxies, offering the best look yet at the universe’s slow fade. Credit: GAMA.
Exactly how that doze will proceed is thoroughly considered in Greg Laughlin and Fred Adams’ The Five Ages of the Universe (1999), which departs from linear time to consider logarithmic cosmological decades. We live, in these terms, in the 10th cosmological decade, approximately 1010 years after the Big Bang. We are, in fact, in the ‘Stelliferous Era,’ when galaxies and stars as we know them continue to shine, as they will through the 14th cosmological decade. But a universe ten thousand times its current age will eventually use up all nuclear fuel. What happens in the Degenerate Era to follow is well beyond our experience but not our ability to project, and if Laughlin and Adams are right, there may be a way for intelligent life to persist, perhaps even into the supremely lengthy Black Hole Era.
But back to GAMA, whose object is to map and model all the energy generated within a large volume of space. In a news release from the IAU, Driver describes that energy this way:
“While most of the energy sloshing around in the Universe arose in the aftermath of the Big Bang, additional energy is constantly being generated by stars as they fuse elements like hydrogen and helium together. This new energy is either absorbed by dust as it travels through the host galaxy, or escapes into intergalactic space and travels until it hits something, such as another star, a planet, or, very occasionally, a telescope mirror.”
The team would like to map and model this energy over the entire history of the universe, a mammoth undertaking that will involve facilities not yet online, such as the Square Kilometer Array scheduled for South Africa and Australia over the coming decade. Until then, what is being reported by the GAMA team is considered the most comprehensive assessment of the energy output of at least the nearby universe. Each galaxy is measured at 21 wavelengths from the ultraviolet to the far infrared. We can only imagine the fictional uses the universe’s slow fade will inspire as we learn more about how it occurs and how intelligence may deal with it.
Addendum: I can’t rush past William Hope Hodgson as quickly as I did, especially since I didn’t even mention his best known work, The House on the Borderland (1908). If you do get interested in Hodgson, and you should, let me recommend Michael Dirda’s comprehensive and highly readable look at the author From Out of the Depths: The Weird Tales of William Hope Hodgson, an online essay at the Barnes & Noble site.
What exactly is the purpose of this study – giving us more precise data on the energy output of the universe since the Big Bang and projections into the future? AFAICS the popular science pieces don’t tell us anything we didn’t already know. Are there any non-obvious (to me) useful observations, for example, pinning down the expansion rates of the universe over time from dark energy?
Here’s how the project is described on the GAMA site:
“Our primary goal is to test the CDM paradigm of structure formation. In particular, the key scientific objectives are:
“To test modified theories of gravity by measuring the growth rate of structure; the CDM model by measuring the halo mass function; and galaxy formation models by measuring the star formation efficiency in groups.
“To measure the connection between star formation fuelling, stellar mass build-up and feedback processes.
“To uncover the detailed mechanisms that govern the build-up of the stellar content of galaxies.
“To directly measure the recent galaxy merger rate as a function of mass, mass ratio, local environment and galaxy type.”
But I would think accumulating data on cosmological expansion would be an off-shoot as well.
Thank you Paul. These goals makes a lot more sense to me. The pop sci articles seem to have focused on the aging aspect.
The aging aspect is the one that GAMA has highlighted in its early press release, but that’s presumably going to change as the real focus emerges with later assessments.
Am I the only one surprised by this half-life of 2 BY? It seems, in the grand scheme of things, an incredibly short time.
Some of William Hope Hodgson are available as ebooks at Project Gutenberg:
http://www.gutenberg.org/ebooks/author/3260
” The House on the Borderland ” reads like Lovecraft. It’s excellent.
The “aging” can be seen more as a maturing. Big, bright stars fortunately only consume a tiny fraction of their hydrogen/helium fraction, then blow it all back into the void to recycle. As the gases are cycled through, the heavy element fraction (“metals” but that means everything other than hydrogen & helium) increases over cosmic time. Heavy elements govern how quickly stars fritter away their fusion potential energy. With a higher fraction, the stars start dimmer and age slower. Plus the minimum mass for sustained hydrogen fusion decreases – in the early days it was ~0.09 solar masses, now it’s 0.07 solar masses. Galaxies get dimmer as they mature, so that eventually more mass is tied up in dimmer, longer-lived stars. They then settle into a longer, more steady luminous phase. Almost a trillion years will see galaxies maintain near constant luminosity, a bit dimmer than the current level.
On Hope Hodgson’s epic, the stellar physics presumed is somewhat out-dated, as it gives a merely multi-million year lifespan to the Sun. However there is a scenario in which it does become possible. Assuming Earth’s survival, after the Sun has become a Red Giant and its shrunken white dwarf core remains, then, if Earth is relocated to 0.01 AU, the luminosity of the Sun will decline as it cools, ultimately reddening and dimming. What’s more the Earth will be tide-locked – one half will become the Night Land, with all the unvisageable Terrors of 50 aeons hence.
The article makes reference to the Big Bang, but recently in the popular press, “The demise of the Big Bang theory–the universe is eternal” has been discussed. (Having an old computer, I can’t open many websites that I once could; I’m working on a new one.) Does the rejection of the Big Bang theory (*IF* it has been–I haven’t heard any mention of Fred Hoyle’s Steady State theory being accepted again, even with revisions) affect the projected dimming or “maturing” of the universe?
For an illuminating discussion of the evolution of the Milky Way’s luminosity, there’s this paper by Greg Laughlin, Fred Adams & Genevieve Graves: Red Dwarfs and the End of the Main Sequence” …essentially the Milky Way will hold steady for the next ~800 billion years before going into a slow decline. Note especially the graph of the luminosity-vs-time.
If mass and energy are equivalent and interchangeable, the universe is presumably growing dimmer but not less “energetic”. This dimming seems like a natural continuation of a universe that has progressed from pure energy at the moment of the Big Bang to a changing mix of mass and energy.
Shouldn’t it be a corollary of (i) the dimming universe and (ii) the conservation of mass-energy that: the universe is becoming more massive as it becomes dimmer?
@Jim Strom: exactly, and one should not forget that dimming EM radiation is ostensibly only a very small fraction of the energy-mass density of the Universe in the current cosmic epoch. We have little information on the supposedly dominant ‘dark sector’. We don’t know what DM is, and how its energy density may evolve with time including how it might convert to dark energy via an EM analog in that sector (‘dark photons’).
@Jason Wentworth: Hoyle’s ‘C field’ (creation field) superficially resembles dark energy. Hoyle posited that it might be enhanced in e.g. quasars (‘white holes’), which we now know isn’t correct. But he also advocated ‘diffuse creation’ of matter, whereas we *think* that dark energy manifests itself more uniformly, without much evidence.
Jim Strom: No, the universe will not become more massive. Galaxies will become less massive by the amount of light that escapes them, but that light will, of course, remain in the universe. It’s added mass will perfectly balance what is lost from the galaxies in the process of emitting it.
“Shouldn’t it be a corollary of (i) the dimming universe and (ii) the conservation of mass-energy that: the universe is becoming more massive as it becomes dimmer?”
Not really. Energy in the form of “matter” and gravitational potential is gradually decaying into energy in the form of thermalized photons. As the universe ages, less and less of the mass/energy is in the concentrated and useful form of matter. More and more of it is in the form of useless low energy EM radiation.
Think of it this way: The reason fusion releases energy is that a Helium atom actually weighs less than four Hydrogen atoms. But the “missing mass” is to be found in the form of the energy released, and the total is unchanging.
Anyway, just recently read “The House on the Borderland” for the third or fourth time. Hodgson is another Lovecraft, well worth reading. Might even have been more famous than Lovecraft, if he hadn’t died in WWI.
G. Cecil wrote:
“@Jason Wentworth: Hoyle’s ‘C field’ (creation field) superficially resembles dark energy. Hoyle posited that it might be enhanced in e.g. quasars (‘white holes’), which we now know isn’t correct. But he also advocated ‘diffuse creation’ of matter, whereas we *think* that dark energy manifests itself more uniformly, without much evidence.”
Thank you. It sounds like our current understanding of these matters may be like Bohr’s understanding of the atom (electrons orbiting within a vague sphere of positive charge) before protons were discovered–“fuzzy,” as in glimpsing something at a distance in rather dim light.