If the speed of anything is indeed limited to c, and if indeed a Star Trek like sub space (faster than light) communication is impossible – wouldn’t it then be impossible for a species to maintain some sort of internal (hierarchical / cohesive) organisational structure – in case the species is dispersed across multiple planets, at least when the distance between the different planets surpasses a certain threshold?
In the first place, and especially when everything is indeed bound to c: Undertaking interplanetary let alone interstellar population – especially of entire species is an ultimately expensive undertaking – one that a species ultimately will only undertake when all resources on the mother planet are depleted, or due to some other form of disaster. A species only does this when it has no other option – after options of getting alternative resources to the mother planet have been depleted. Anything rather than having to ship part of your population to another planet – let alone your entire species (if at all possible) – let alone to another star (if at all plausible).
I’d imagine that a ‘mother planet’ will sooner rather than later lose its influence over a ‘child planet’:
– a child planet will need to sort out her problems on her own – without the help of a mother planet multiple light years away
– a mutually beneficial relationship doesn’t seem to be logical once a certain threshold in distance has been surpassed
– this goes for information / communication (for government and for guidance) let alone goods or auxiliaries
Only an – in development, equipment, resources, and or status – very unequal relationship might last. Especially when a child planet is dependent on its mother for some or other vital resource.
Mothers and children will sooner rather than later breach – violently or peacefully – at least maintaining some sort of federal order and regime seems unmaintainable. Not for thousands, not for hundred thousands, let alone Myrs or Gyrs. Eras one would imagine to need to build hyper stellar infrastructures.
Thus advanced species are bound to be bound to solitary planets (or a group close to each other).
– And have nor the ability nor the urge – ultimately – to rule large quadrants of the universe – or let themselves be at all known to possible others – only through Very energy expensive infrastructures. All they would benefit from this would be knowing that they’re not alone, but at what cost and what risk.
Individual advanced species on their solitary (groups of) planets have nothing other to gain and will therefore ultimately not undertake this all too expensive endeavour. Ultimately there’s nothing other to gain but risk.
So: The universe might be oozing with intelligent life but due to c all presence remains local – bound to individual (groups) of planets, and due to this inability to build and Maintain interplanetary / interstellar infrastructures and or federations – no infrastructure or species can / will become large and or developed enough to have themselves known to others, to us. And for a local, developed species on its solitary planet there’s nothing to gain, only to risk by having themselves known throughout.
I’m not saying that spatiotemporal limitations aren’t diminished, and that interstellar travel won’t be practically doable in the foreseeable future (and that many other species before us have had the technical ability) – I’m saying that it’s impossible to build and maintain an interplanetary / interstellar federal structure due to c. And that this is ultimately the reason of the cosmic silence.
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