The Pandorica opens in the Xeeleeverse

[mr friendly guy]

I need some help from Xeelee experts to answer this.

After escaping the photino birds the Xeelee escapes into the Whoverse and observes some interesting things. They notice that a time explosion on 26 June 2010, the day of Amy's wedding to Rory causes cracks in time. They notice every star in the universe going out after the events of the "Pandorica opens" and notice the Doctor resetting things in the next episode using the Pandorica.

By an act of authorial fiat, the Xeelee eventually gets hold of some Whoverse tech, including a TARDIS and a new Pandorica with whatever Whoverse tech they encounter. They now plan to repeat the same things in their old universe and then reboot it to defeat the photino birds. The idea is reality gets wiped out including the dark matter birds. Just before all of reality gets wiped out reboot the universe.

My question for those Xeelee experts, will it work? Assume that they follow the Doctor for the next season where we hopefully find out the agency which made the TARDIS to cause the time explosion, and gain its knowledge on how to do that.

[Xenophobe3691]

But the Xeelee already have time travel, due to their use of FTL drives...

[Dahak]

And "it's bigger on the inside" space folding.

[Crossroads Inc.]

Didn't the Xeelee use time travel to "escape" the photino birds?
I swear I recall one book that delt with a group of exiles who "survived" by existing within a certain time period of the universe. After a few thousand years that would jump back in time and continue existing in another part of the universe, each time going back to an unnoccupied planet.

Or I could be thinking of another sci fi story.

[Imperial Overlord]

Didn't the Xeelee use time travel to "escape" the photino birds?
I swear I recall one book that delt with a group of exiles who "survived" by existing within a certain time period of the universe. After a few thousand years that would jump back in time and continue existing in another part of the universe, each time going back to an unnoccupied planet.

Or I could be thinking of another sci fi story.

No. The Xeelee used time travel to reboot their war against the photino birds when they lost the first time. They went to the beginning of time and gave all their knowledge to the first Xeelee to boost strap their civilization. They still lost. They eventually fled our universe for one that had no dark matter.

[mr friendly guy]

But the Xeelee already have time travel, due to their use of FTL drives...

Yeah I know. The question is can their time travel be rigged to create a plot device time explosion which wipes out most of the universe except a certain spot, from which you can reboot it again (with changes).

[Molyneux]

Didn't the Xeelee use time travel to "escape" the photino birds?
I swear I recall one book that delt with a group of exiles who "survived" by existing within a certain time period of the universe. After a few thousand years that would jump back in time and continue existing in another part of the universe, each time going back to an unnoccupied planet.

Or I could be thinking of another sci fi story.

No. The Xeelee used time travel to reboot their war against the photino birds when they lost the first time. They went to the beginning of time and gave all their knowledge to the first Xeelee to boost strap their civilization. They still lost. They eventually fled our universe for one that had no dark matter.

I have not read the relevant books, but...if you already have knowledge of time travel, why wouldn't they try to bootstrap themselves again, with all the accumulated knowledge of both universes? Any conflict where only one side has time travel seems a foregone conclusion to me, though it may take awhile to get to it.

[mr friendly guy]

I have not read the relevant books, but...if you already have knowledge of time travel, why wouldn't they try to bootstrap themselves again, with all the accumulated knowledge of both universes? Any conflict where only one side has time travel seems a foregone conclusion to me, though it may take awhile to get to it.

I haven't read the books either, but I gathered that their enemies are made of dark matter. Since most of the universe is dark matter, no matter how far they travel back in time, their enemies will always outnumber them. Their enemies of course have vast natural powers as well, namely they apparently outmass the baryonic universe (most matter which we are familiar with is baryonic).

[The_Saint]

Not exactly sure how the Dr Who reboot mechanic works but I got the feeling they'd reboot the universe and go "whee!! look ... no birds" and with that thought usher them into existence ... or something. I thought it relied a lot on Amy 'remembering' everything back into existence.

[Xon]

Fundamentally, the Xeelee are just too big physically to fit into the universe when it was small enough that dark matter doesn't exist.

Plus thier own reality-wide editing technology is way too much potluck, as it basicly resolves to somehow tinkering with supermassive blackholes where the Monads live in. Even then, we are told various vacuum meta-stability events propagate at lightspeed, and then your opponent has an FTL drive , it simply isn't fast enough to prevent the otherside triggering thier own vacuum meta-stability event to cancel out yours.

[mr friendly guy]

I just rewatched the last episode (hey I got season 5 on dvd), but it seems that Amy remembering was just to bring the Doctor back (somehow). To bring the universe back the technobabble explanation was that some small amounts of the original universe was preserved in the Pandorica, and by flying it into the TARDIS it will spread to all points in time and sort of like cloning from a single cell, some technobabble will allow it to reproduce itself.

To prevent the photino birds coming back, they would simply need to find another universe where they can "clone" from the Pandorica. By this stage they had clearly found other refugee universes, of which presumably some if not most don't have the photino birds in them.

Or since I stipulated they get TARDIS technology, just use the inside of a TARDIS as the template for your new universe, since according to BBC, the inside is a separate universe.

Now I wait for those Baxter fans to tell me if this plan works, or am I just pulling it from a hat.

[Sriad]

Didn't the Xeelee use time travel to "escape" the photino birds?
I swear I recall one book that delt with a group of exiles who "survived" by existing within a certain time period of the universe. After a few thousand years that would jump back in time and continue existing in another part of the universe, each time going back to an unnoccupied planet.

Or I could be thinking of another sci fi story.

No. The Xeelee used time travel to reboot their war against the photino birds when they lost the first time. They went to the beginning of time and gave all their knowledge to the first Xeelee to boost strap their civilization. They still lost. They eventually fled our universe for one that had no dark matter.

I have not read the relevant books, but...if you already have knowledge of time travel, why wouldn't they try to bootstrap themselves again, with all the accumulated knowledge of both universes? Any conflict where only one side has time travel seems a foregone conclusion to me, though it may take awhile to get to it.

Some of this is inference, but all well backed by the books.

All parties involved have time travel to a degree; even Mankind, when they waged a 1000 year war to kick the Xeelee out of the Milky Way, used time travel very heavily to repeat the same battles over and over until they'd reached the most favorable plausible outcome... while the Xeelee were doing the same thing.

In the entire series we never see the Photino Birds' point of view, but it's reasonable to assume they have approximate technological parity with the Xeelee since 1: their "Kill All Large Stars" effort has covered the entire cosmos for billions of years and 2: they won. So, after many decabillion-year long iterations, the war was established in the form we see: the Xeelee have no hope of victory because their foe has ~10 times as much mass to work with, giving the Birds insurmountable strategic superiority. They're committed to a fighting retreat inward to their Ring, escaping into more hospitable universes through their naked-ring-singularity portal.

The Birds are satisfied with this arrangement because the Xeelee have enough baryonic-matter-based tactical advantage in individual conflicts that to decisively win they would have to divert more resources from the KALS effort than is optimal.

[Sriad]

I just rewatched the last episode (hey I got season 5 on dvd), but it seems that Amy remembering was just to bring the Doctor back (somehow). To bring the universe back the technobabble explanation was that some small amounts of the original universe was preserved in the Pandorica, and by flying it into the TARDIS it will spread to all points in time and sort of like cloning from a single cell, some technobabble will allow it to reproduce itself.

To prevent the photino birds coming back, they would simply need to find another universe where they can "clone" from the Pandorica. By this stage they had clearly found other refugee universes, of which presumably some if not most don't have the photino birds in them.

Or since I stipulated they get TARDIS technology, just use the inside of a TARDIS as the template for your new universe, since according to BBC, the inside is a separate universe.

Now I wait for those Baxter fans to tell me if this plan works, or am I just pulling it from a hat.

I'm not solid enough on the Who-tech to say for sure, but by the time they have access to other universes the Xeelee are in as close to a Happy Place as a civilization can get in the Xeelee-verse. By controlling the fluctuations of the outer ring they can change the parameters of the universe that will be reached by traveling through the inner ring to their liking, mostly extremely hot and young universes with less dark matter than baryonic... so access to the TARDIS is a bit of a moot point.

[ThomasP]

The Xeelee's time travel seems to have some limits to it. One of the shorts in Resplendent (or this might have been in Exultant, it's been awhile since I've read either) talks about the Xeelee having come into being in three stages, with the third being the 'baryonic' variants that featured in the stories. The two primordial versions pre-dated matter forming after the Big Bang.

There's no mention of the Xeelee discovering the photino birds during those early eras, as dark-matter life wasn't discovered until star formation had begun. The Sugar Lumps, the Xeelee time ships, might have had some kind of constraints on traveling back to those earlier eras; the primordial Xeelee were mentioned to already have universe-altering technology (given that they were credited with kicking off inflation...), so why didn't they just alter physical laws from that point so that dark matter never came into existence?

Not sure how that will affect the scenario, but it's worth mentioning.

[Sriad]

It's been a while since I've read Resplendent/Exultant too, but my recollection is that to the extent they played a role in triggering inflation's form they did it as damage control. It was like the Big Rip would be to us, but the pre-inflation societies had just enough control

I have a couple competing (or possibly complementary) pet theories:
-Altering the post-inflation universe drastically enough to prevent dark matter's ascendancy has implications serious enough for their own survival in any recognizable form that they just don't.

-They know the Monads love a good war enough they won't allow it.

-It's politically non-viable because the pre-inflation societies were in irreconcilable competition with one another until it was too late to do anything more. This seems especially likely given the alien relations we explicitly see in the Xeelee Sequence.

-It's simply the best utilitarian choice. Even though the Bird War was 13 billion years of fighting retreat it compelled them to build the Ring which from a certain point of view lets them custom-build universes. And they need the tech to GTFO to escape heat-death anyway.

Of course, it's also entirely possible that they can't travel back to before, say, 1,000,000 years post-big-bang because of whatever reason. That's the simplest (though to me less satisfying) explanation.

[Xon]

The Xeelee hyperdrive (and thus timetravel) functions 'better' when the curvature of spacetime is flatter. The higher the degree of curvature the harder it is to plot a time-like path to where/when-ever you want to execute an FTL jump to.

[ThomasP]

It's been a while since I've read Resplendent/Exultant too, but my recollection is that to the extent they played a role in triggering inflation's form they did it as damage control. It was like the Big Rip would be to us, but the pre-inflation societies had just enough control

You're probably right. I have half a recollection of there being some kind of war, and the proto-Xeelee civilization flipping a metaphorical switch (I think that's the wording that was used) to send the enemy past their light-horizon, but that's all I can remember. It might well have been a natural thing that they accelerated and I'm just not remembering that detail.

Still pretty humbling as technologies go, either way

The Xeelee seemed pretty consigned to 'losing' their war, though it's never made clear if they couldn't win (which would be impressive) or just found a better alternative in the Ring and decided to go with that. I'd be inclined to go with that idea rather than saying it was beyond their power, given everything else they did.