Do civ­i­liza­tions have the ca­pac­ity to sur­vive?

It’s time to ask where our own plan­e­tary civ­i­liza­tion falls on the spec­trum

Truro Daily News - - Opinion - Gwynne Dyer Gwynne Dyer’s new book is Grow­ing Pains: The Fu­ture of Democ­racy (and Work).

“The uni­verse is a pretty big place,” as Carl Sagan once re­marked. “If it’s just us, seems like an aw­ful waste of space.”

The Drake Equa­tion is grad­u­ally fill­ing out, and it’s look­ing good for the ex­is­tence of life, the rise of in­tel­li­gence, and the likely num­ber of civ­i­liza­tions else­where in the uni­verse.

There’s even rea­son to hope that some high-en­ergy tech­no­log­i­cal civ­i­liza­tions suc­cess­fully pass through the en­ergy- en­vi­ron­ment bot­tle­neck that our own plan­e­tary civ­i­liza­tion is now en­ter­ing.

But not many make it through the bot­tle­neck with­out suf­fer­ing ma­jor losses, and quite a lot just col­lapse.

The Drake Equa­tion was writ­ten by Amer­i­can ra­dio as­tronomer Frank Drake in 1961 to es­ti­mate how many high- tech civ­i­liza­tions there were in the gal­axy. It had seven fac­tors, but they were all empty.

The first three fac­tors, all un­cer­tain in 1961, were: what is the aver­age rate of star for­ma­tion in our gal­axy; how many of those stars have plan­ets; and what pro­por­tion of those plan­ets can po­ten­tially sup­port life? We know the an­swers now, and they are pretty en­cour­ag­ing.

There’s around one new star an­nu­ally, most stars have plan­ets, and about one star in five hosts one or more plan­ets with liq­uid wa­ter on the sur­face.

That means there are prob­a­bly around a hun­dred bil­lion plan­ets in this gal­axy alone that can sup­port life, but that’s just a start.

As Dou­glas Adams pointed out in The Hitch- Hiker’s Guide to the Gal­axy, “Space is big. Re­ally big. You just won’t be­lieve how vastly, hugely, mind-bog­glingly big it is.”

The Hub­ble tele­scope has re­vealed around a hun­dred bil­lion gal­ax­ies in the uni­verse. To­tal num­ber of po­ten­tially life-sup­port­ing plan­ets? Around 10,000,000,000,000,000,000,000 (ten bil­lion tril­lion).

Drake’s re­main­ing fac­tors are still un­known quan­ti­ties. The only two that mat­ter for Adam Frank – be­cause all he wants to know is how many non-hu­man civ­i­liza­tions have ever ex­isted any­where in the uni­verse – are what frac­tion of po­ten­tially life­sup­port­ing plan­ets ac­tu­ally do de­velop life; and what pro­por­tion of those plan­ets go on to de­velop in­tel­li­gent life.

What Adam Frank has done, in his re­cent book, Light of the Stars: Alien Worlds and the Fate of the Earth, is to point out that there must there­fore have been a lot of ‘exo-civ­i­liza­tions’.

Make your as­sump­tions about first life and then in­tel­li­gence emerg­ing on any given planet as pes­simistic as you like, and there will still be a lot.

Maybe not bil­lions or even mil­lions, but even if you as­sume that only one life- sup­port­ing planet in a mil­lion tril­lion ever sup­ported a civ­i­liza­tion, there would have been 10,000 of them.

That’s big enough for a sta­tis­ti­cal sam­ple, and what Frank re­ally wants to do is to crank the num­bers and get a han­dle on how many of those civ­i­liza­tions would have made it through the bot­tle­neck.

He doesn’t need to know any­thing spe­cific about those un­known exo- civ­i­liza­tions. He only needs to know that all civ­i­liza­tions use large amounts of en­ergy, and that there is a strictly lim­ited num­ber of ways that a tech­no­log­i­cally ‘ young’ civ­i­liza­tion like ours can ac­cess en­ergy.

There are fos­sil fu­els, if your planet had a Car­bonif­er­ous Era, or just burn­ing bio­ma­te­ri­als if it didn’t.

There’s hy­dro, wind and tides. There’s so­lar, geo­ther­mal and nu­clear.

That’s it.

Us­ing en­ergy al­ways pro­duces waste, but some of these modes pro­duce far less heat, car­bon-diox­ide, and toxic chem­i­cals than oth­ers.

So put dif­fer­ent orig­i­nal mixes of these en­ergy sources into your ex­per­i­men­tal models, put in dif­fer­ent plan­e­tary con­di­tions as well ( some plan­ets closer to their suns, some fur­ther away), and run a few thou­sand of these models through your com­puter.

It turns out most of the models see run­away pop­u­la­tion growth, fol­lowed at a dis­tance by grow­ing pres­sures on the planet’s en­vi­ron­ment that low­ers the ‘pop­u­la­tion-car­ry­ing ca­pac­ity’.

At some point the alarmed pop­u­la­tion switches to lower-im­pact en­ergy sources. There is still a steep die-back (up to 70 per cent) in the pop­u­la­tion, but then a steady state emerges, and the civ­i­liza­tion sur­vives.

In other models, the planet’s peo­ple ( crea­tures? be­ings?) de­lay switch­ing the en­ergy sources for too long.

They all switch in the end, but the lag­gards still don’t make it.

The pop­u­la­tion starts to fall, then ap­pears to sta­bi­lize for a while, then rushes down­ward to ex­tinc­tion. No­body saw that one com­ing, but it’s what the models are telling us.

There’s still a huge amount of re­search to be done in this new do­main, but it’s time to ask where our own plan­e­tary civ­i­liza­tion falls on this spec­trum of pos­si­ble be­hav­iours.

I don’t know, but this just in. Oil pro­duc­tion is at an all-time high of 100 mil­lion bar­rels a day, and the Or­ga­ni­za­tion of Pe­tro­leum- Ex­port­ing Coun­tries pre­dicts that it will reach 112 mbd in the next 20 years.

That’s the wrong di­rec­tion.

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