Yet another quandary

[Karn Maeshalanadae]

So many threads, so many subjects, so little time.


Okay. This time, the question does not deal with gods or creatures, but this time with stars. My new situation is....


Given all that we have theorized about the universe, is it too much of a stretch of the imagination for there to be a supernova caused by a Red Giant rogue star, situated between the Milky Way and Andromeda galaxies, to cause a chain reaction to affect planets with life in both those galaxies?

 

[David Evil Overlord]

Short answer -- I don't know.

Long answer -- In Larry Niven's novels set in the Known Space universe, there is a supernova in the galactic core (Milky Way galaxy). Because the stars are so closely packed in the core, the supernova affects nearby stars, causing more supernovae. The resulting radiation is due to reach Earth some 20,000 years later. By then, the human race faces either extinction or the need to relocate to somewhere safe (like the Magellenic Clouds).

The alien puppeteers left the moment they found out (since they are cowards, and one thing they fear is hyperspace, so they have to go sublight). Most other races don't plan that far ahead.

Not sure if there are enough stars in intergalactic space to cause the destruction you seek. Galactic cores are more likely. Hmmm. Gives me an idea involving a wormhole transit system, a lack of understanding of gravitational warping of wormholes, a galactic core, and destruction on a very, very large scale.

 

[Galacticdefender]

There is so much space in between two galaxies that a supernova would probably not affect them at all. I'd consider it a stretch for even soft scifi.

 

[AlcubierreWarp]

So many threads, so many subjects, so little time.


Okay. This time, the question does not deal with gods or creatures, but this time with stars. My new situation is....


Given all that we have theorized about the universe, is it too much of a stretch of the imagination for there to be a supernova caused by a Red Giant rogue star, situated between the Milky Way and Andromeda galaxies, to cause a chain reaction to affect planets with life in both those galaxies?

A few issues with your situation.

1. Red Giants do not become Supernovae. Red giants are far too cool (relatively speaking) to precipitate the required temperatures for a supernova. Generally speaking it is a White Dwarf which collects enough mass to surpass the Chandrasekhar limit which then collapses into a supernova. So it is plausible that a red giant which is in a binary system with a white dwarf would feed the white dwarf enough to cause a supernova, but it would not be the red giant which goes supernova itself. That's for Type IA supernovae. For type II supernovae, they're hot enough that they would not emit light in the red spectrum.

2. Whether or not your supernova affects life in both galaxies depends on what you mean by affect. If you mean the natives of both galaxies saw a pretty light in the night sky (as Supernovas appear like bright stars), and they wrote stories about it which might have changed their evolution, then yes, it could affect them (although the light would take about 1.25 million years to reach either galaxy).

If you mean it would physically affect them (knock out power, change planetary orbits, kill people, cataclysm, etc.) then no, it would not. Any material or shockwave ejected by the supernova would travel at subluminal speeds, and would have dissipated due to cosmic winds by the time it reached either of the galaxies.

 

[Karn Maeshalanadae]

Alright. It seems I would have to find something else then. I don't want to throw logic out the window for this.

 

[Galacticdefender]

Quasars could possibly do something, though from a different galaxy.

http://en.wikipedia.org/wiki/Quasar

 

[Karn Maeshalanadae]

Yes, but there are no quasars in either of the galaxies....okay. As a reader, can anyone give me any plausible scenarios that could wipe out planets in two separate galaxies, at the same time? (Relatively, of course.)

 

[David Evil Overlord]

Yes, but there are no quasars in either of the galaxies....okay. As a reader, can anyone give me any plausible scenarios that could wipe out planets in two separate galaxies, at the same time? (Relatively, of course.)

Very warlike and xenophobic aliens, who set off for both galaxies about a billion years ago?

Very warlike and xenophobic aliens, who also have an advanced transit system using wormhole technology that turns all those millions of years of FTL travel between galaxies into a single second of travel?

Profiteering aliens, who cause an economic meltdown when they purchase both planets for the high-tech equivalent of some shiny beads? To recover their losses, they strip-mine both planets until what remains cannot support life of any kind.

An accident (or was it?) that links the planet-based wormholes of an advanced transit system with a location not suited to planet-based life -- such as the heart of a White Dwarf star, a supernova, or a quasar?

Or the wormhole system causes two planets to occupy the same space at the same time?

Sorry, but with the distances involved, I can't see any easy way to do this without bypassing the distance with wormholes.

Or time travel. What would happen if the sentient races of both worlds were trying to go back in time to deflect an ancient cosmic accident that dooms their world? But the only way for each race to live is to doom the other race...

 

[Karn Maeshalanadae]

I would probably have to resort to time travel or wormholes...

Both planets, Earth and Morcalia, are in alliance with one another. The way I want to set it up is, both planets get destroyed at roughly the same time; within perhaps just five or ten Earth years of one another at most. Then two gods, one of each planet, pool what magical resources they have left to use the remainders of each planet to build a new one for evolution to start again...

 

[Venusian Broon]

What about cosmic strings?

http://en.wikipedia.org/wiki/Cosmic_string

They are 1 dimensional cracks that (might) have formed during the big bang. We don't know if they exist. But if they do, despite only being one dimensional they will be of vast size by now (order of the size of the universe and will utterly dwarf galaxies) and be all over the place. Put one in between our galaxy and Andromeda. Have it 'shift' or perhaps 'collapse in' - a bit like a rift in plate tectonics, like the san andreas fault which relaxes with an earthquake when it is stresed - and the results rearrange quantum spacetime could create an onrushing wave in all directions along a huge volume of space of deadly radiation, high energy particles, gravity waves or whatever you fancy!

I haven't thought this through so it might not work, but hey - we don't know if they exist and there pretty exotic so you can make more or less anything you want to happen!

I know of some theories of galaxy formation that use these 1-d strings as sort of condesation centres - as a way of explaining why some areas of the universe are lumpy and full of matter and some are empty. Essentially they state that the fractures in space attract matter.

 

[Interference]

Galactic distances are almost incomprehensibly huge, Karn. Atoms-in-the-desert-type huge.

All I can think of is a pan-dimensional effect, where space dimensions are irrelevant. An event at this level could possibly have a simultaneous effect, in the spacetime dimension, on individual planets in different galaxies.

 

[Moonbat]

How about QED, but on a macro-planetary-scopic range.
The two planets could be quantumly entangled, and so the destruction of one instantly destroys the other. Not really scientifically plausible, but could even be changed to work as a schrodingers planet way,
A planet exists in one of three different galaxies but until it is observed in one specific galaxy it exists in all three of them, and then when it is observed the wavefront collapses and only one planet is left, the other two are destroyed.

Trouble it this doesn't leave any bits of planet lying around for your Gods to combined into a new planet. Sorry. Ignore my post.

 

[Karn Maeshalanadae]

This does put me at a quandry because as I said I don't want to throw logic out the window completely.

I know quasars are not a possibility because they're only at the far edges of the universe, and space debris would be too conveniently coincidental...hmm...



Okay, how about this scenario, going off a wormhole experiment:


NASA and other space programs, funded by their respective governments, experiment with wormholes to create a dimensional pathway between Earth and Morcalia as a trade shipping route, but the wormhole soon grows out of control and starts to suck in both planets, until they collide with one another?

Or is that a bit of a stretch?

 

[Venusian Broon]

I wouldn't be too concerned about logic and wormholes.

It seems you are describing something akin to a Stargate SG-1 sort of thing.

But In reality, from the solutions of general relativity that produce a wormhole, it would probably need a massive black hole (none near earth then) and also require a white hole for the exit (an object that has never ever been observed in our universe). In fact double it, if you want two-way transport. You'd have to invent a whole new physics (and logic) to get round this rather difficult starting position

To be honest, your distances between the two planets are just too far. Andromeda to Earth is 2.6 million light years. To put that in perspective - light reaching us now from Andromeda left when there was no such thing as homo sapians.

Connecting the two regions is going to be tough.

 

[Karn Maeshalanadae]

I can ignore the theories of relativity to a point; these planets not only have had contact with one another, they're allies.

But as I said, I don't want to throw logic out COMPLETELY. I do want an at least semi-plausible scenario, even if the chances of it are near zero.

 

[Venusian Broon]

Mind you, if you've already got the two of them connected and allies - is this because of the wormhole or through some other means?

If it's your wormhole then that's is the most obvious way to spill disaster out at either end. In Greg Bears 'Eon' the future humans open a portal into the heart of a star and let it nova inside the infinite tube inside the asteriod to save themselves from the bad guys. So perhaps you could have someone connect another wormhole to the original Earth-Morcalia wormhole in the middle, to some nasty stellar object and the result devastates the worlds.

 

[Karn Maeshalanadae]

No, the time the destruction of the planets is going to take place is ~6500 A.D. Earth time, they had been allies for two thousand years at that point, about.

Experiments with stable wormholes have just begun.

 

[David Evil Overlord]

There are things out there in interstitial space, in-between our universe of spacetime and the other dimension of the wormholes. By making wormholes, we have awakened those things. And they are hungry...

 

[Venusian Broon]

Ok starting to get to grips with your ideas...

So how did two planets so astronomically far apart (and astronomically is indeed rightly used in this case), manage to get in touch with each other?!?

- very, very, very fast spaceships? (Timeships really if you still have normal physics with the characters if they stay relatively still)? Or something else. As it wasn't wormholes.

 

[Interference]

6500 AD and only now experimenting with stable wormholes? I should imagine that, by this time, wormholes would be old hat and either dismissed as impractical or used for limited purposes (limited by the value of wormholes themselves). I would definitely imagine that a surviving human race would, in 4000 years' time, be involved more closely in metaphysical sciences which will, of course, render all spacetime limitations impotent. This explains the alliance between planets in far distant galaxies.

Have another look at http://www.sffchronicles.co.uk/forum/534561-a-handy-scale-of-the-universe-thingy.html and the question of why galaxies need alliances becomes clearer. They can't be operating under the same restrictions as we are in travelling astronomical distances to begin with, so clearly our bubble of spacetime has been somehow escaped. Only quantum physics currently gives us a clue to how this might be done, but remember that quantum physics has only been a viable study for under 100 years at this moment. Wormholes aren't much older, in theoretical terms. Add a zero and multiply by 4 and what other areas of physics will have been discovered?