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Old 26th November 2017, 08:16 PM   #321
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Originally Posted by Jodie View Post
Most inventions and theory build upon what we already have.
Irrelevant to traversable wormholes which require things we do not have and may not even exist such as exotic matter or a negative mass cosmic string.
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Old 27th November 2017, 02:00 AM   #322
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So, compared to some even I am thinking small with my comet as a spacecraft idea. In this episode of his podcast, Isaac Arthur suggests using Jupiter*:

https://www.youtube.com/watch?v=PQnvjGN91Mg

It's around the 28 minute mark.

*The moons of Jupiter would come along for the ride in this scenario.
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Old 27th November 2017, 02:15 AM   #323
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Originally Posted by Roboramma View Post
So, compared to some even I am thinking small with my comet as a spacecraft idea. In this episode of his podcast, Isaac Arthur suggests using Jupiter*:

https://www.youtube.com/watch?v=PQnvjGN91Mg

It's around the 28 minute mark.

*The moons of Jupiter would come along for the ride in this scenario.
he also talks about using dyson swarms to strip stars of some of their mass to stop them going super nova and a by product of doing that means you have
reaction mass

http://www.internationalskeptics.com...2#post12057952

the whole solar system would come along for the ride in this case

this is more of a brute force thing too there isnt really any exotic technology needed (at least nothing we're not pretty close to already doing)
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Old 2nd December 2017, 04:51 PM   #324
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Originally Posted by Reality Check View Post
Irrelevant to traversable wormholes which require things we do not have and may not even exist such as exotic matter or a negative mass cosmic string.
That doesn't mean that the research we are doing today can't lend itself to future research that does, that's an asinine assumption on your part.

http://time.com/4517897/nobel-prize-physics-2016/

"Thouless, Haldane and Kosterlitz found that at different energy levels or at supercold temperatures, topological phase transitions can occur in thin films of matter, causing tight pairs of vortices that spin in close proximity to separate—a little like a catamaran separating into two free-floating boats—and that has superconductive and superfluid implications. That doesn’t quite upend existing topology—as it would if a second or third hole appeared out of nowhere. But in terms of the behavior of the material it’s close, as illustrations (above) released by the Nobel Committee reveal. The prize-winners also showed that these changes happen in predictable integers or steps, like the thermometer falling a degree at a time until it reaches 32º F or 0º C and water freezes.

Nobody in Stockholm, where the Nobel Committee meets, pretends that any of this has immediate applications, but it will. Superconductivity and superfluidity occurring in extremely thin layers have very real potential in all matter of engineering fields, including computing. And better understanding of phase transitions and states of exotic matter can be helpful in simulating and studying quantum states. It’s not as straightforward as doughnuts and coffee, but eventually it will be vastly more important."
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Old 2nd December 2017, 05:14 PM   #325
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Originally Posted by Jodie View Post
That doesn't mean that the research we are doing today can't lend itself to future research that does, that's an asinine assumption on your part.

http://time.com/4517897/nobel-prize-physics-2016/

"Thouless, Haldane and Kosterlitz found that at different energy levels or at supercold temperatures, topological phase transitions can occur in thin films of matter, causing tight pairs of vortices that spin in close proximity to separate—a little like a catamaran separating into two free-floating boats—and that has superconductive and superfluid implications. That doesn’t quite upend existing topology—as it would if a second or third hole appeared out of nowhere. But in terms of the behavior of the material it’s close, as illustrations (above) released by the Nobel Committee reveal. The prize-winners also showed that these changes happen in predictable integers or steps, like the thermometer falling a degree at a time until it reaches 32º F or 0º C and water freezes.

Nobody in Stockholm, where the Nobel Committee meets, pretends that any of this has immediate applications, but it will. Superconductivity and superfluidity occurring in extremely thin layers have very real potential in all matter of engineering fields, including computing. And better understanding of phase transitions and states of exotic matter can be helpful in simulating and studying quantum states. It’s not as straightforward as doughnuts and coffee, but eventually it will be vastly more important."
It's interesting physics, but utterly irrelevant to faster than light travel.

Anymore than superconductors help us communicate with Kal El.
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Old 3rd December 2017, 06:53 AM   #326
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Eight-plus pages, lots of hoop-jumping & speculation, & it still appears the answer is "no."
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Old 3rd December 2017, 08:18 AM   #327
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Originally Posted by Peregrinus View Post
Eight-plus pages, lots of hoop-jumping & speculation, & it still appears the answer is "no."
Or there is no known answer. My own guess is that interstellar travel may be accomplished by our intellectual descendants, if they are thinking machines, as I believe they will be; but that it can't be achieved by natural organisms like our present selves.

Intergalactic travel is unthinkable in the absence of FTL travel, and I believe that is ruled out by the structure of the universe.
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Old 3rd December 2017, 09:25 AM   #328
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Originally Posted by Craig B View Post
Or there is no known answer. My own guess is that interstellar travel may be accomplished by our intellectual descendants, if they are thinking machines, as I believe they will be; but that it can't be achieved by natural organisms like our present selves.

Intergalactic travel is unthinkable in the absence of FTL travel, and I believe that is ruled out by the structure of the universe.
Given that Andromeda is on a collision course with us, if you wait long enough intergalactic travel really only requires interstellar travel.

I haven't seen anyone who thinks it can't or won't happen comment on RY's suggestion of similarly waiting for the stars to come to us rather than going to the stars.
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Old 3rd December 2017, 11:41 AM   #329
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Originally Posted by Jodie View Post
That doesn't mean that the research we are doing today can't lend itself to future research that does, that's an asinine assumption on your part.

http://time.com/4517897/nobel-prize-physics-2016/

"Thouless, Haldane and Kosterlitz found that at different energy levels or at supercold temperatures, topological phase transitions can occur in thin films of matter, causing tight pairs of vortices that spin in close proximity to separate—a little like a catamaran separating into two free-floating boats—and that has superconductive and superfluid implications. That doesn’t quite upend existing topology—as it would if a second or third hole appeared out of nowhere. But in terms of the behavior of the material it’s close, as illustrations (above) released by the Nobel Committee reveal. The prize-winners also showed that these changes happen in predictable integers or steps, like the thermometer falling a degree at a time until it reaches 32º F or 0º C and water freezes.

Nobody in Stockholm, where the Nobel Committee meets, pretends that any of this has immediate applications, but it will. Superconductivity and superfluidity occurring in extremely thin layers have very real potential in all matter of engineering fields, including computing. And better understanding of phase transitions and states of exotic matter can be helpful in simulating and studying quantum states. It’s not as straightforward as doughnuts and coffee, but eventually it will be vastly more important."
You're just trying to rescue your wrong claim that wormhole research was currently under way.
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Old 3rd December 2017, 03:27 PM   #330
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Originally Posted by Jodie View Post
That doesn't mean that the research we are doing today can't lend itself to future research that does, that's an asinine assumption on your part.
An "asinine assumption" is that past research producing results automatically means that future research on things we think are physically impossible but hypothetically may exist will succeed.

An actually "asinine assumption" is that a Nobel prize in superconductors is relevant to traversable wormholes. It is almost as if you Googled 'exotic matter' and posted the first credible but irrelevant link you found.
Why 'Exotic Matter' Matters—and Won the Nobel Prize in Physics
Quote:
Nobody in Stockholm, where the Nobel Committee meets, pretends that any of this has immediate applications, but it will. Superconductivity and superfluidity occurring in extremely thin layers have very real potential in all matter of engineering fields, including computing. And better understanding of phase transitions and states of exotic matter can be helpful in simulating and studying quantum states. It’s not as straightforward as doughnuts and coffee, but eventually it will be vastly more important.
The "exotic matter" is thin film superconductors. This is normal matter in a state that we do not usually see. There are other examples of "exotic matter", e.g. Bose-Einstein condensates.

Irrelevant to traversable wormholes which require things we do not have and may not even exist such as exotic matter or a negative mass cosmic string.
If you bothered to learn about traversable wormholes then you would know that this needs exotic matter with negative energy density or a negative mass cosmic string.

Last edited by Reality Check; 3rd December 2017 at 03:29 PM.
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Old 3rd December 2017, 03:46 PM   #331
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Originally Posted by Jodie View Post
That doesn't mean that the research we are doing today can't lend itself to future research that does, that's an asinine assumption on your part.

[...]"
If we all were to place wagers about who is making asinine assumptions, I know which line I'll be standing in.
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Old 3rd December 2017, 05:00 PM   #332
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Originally Posted by Roboramma View Post
...if you wait long enough ...
how long have you got? Waiting billions of years for a galaxy to crash into us isn't my idea of "Travel".

What would you rather do? Fly to America or wait for plate tectonics to bring America back in our direction?
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Old 4th December 2017, 08:28 AM   #333
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Originally Posted by Craig B View Post
how long have you got? Waiting billions of years for a galaxy to crash into us isn't my idea of "Travel".

What would you rather do? Fly to America or wait for plate tectonics to bring America back in our direction?
We were talking about whether or not it's possible. If it's impossible to fly (or sail) to America, waiting for America to come to you might be the only way that life spreads from one continent to another, but life will spread.
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Old 5th December 2017, 03:24 AM   #334
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Originally Posted by Roboramma View Post
We were talking about whether or not it's possible. If it's impossible to fly (or sail) to America, waiting for America to come to you might be the only way that life spreads from one continent to another, but life will spread.
Only if other conditions stay the same, by the time the continents rejoin the earth may no longer be capable of supporting life.
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Old 5th December 2017, 03:28 AM   #335
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Originally Posted by Roboramma View Post
We were talking about whether or not it's possible. If it's impossible to fly (or sail) to America, waiting for America to come to you might be the only way that life spreads from one continent to another, but life will spread.
How can you know that? It will spread if it has the opportunity to spread, like every other natural entity. It is not a supernatural force with a predetermined destiny.
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Old 5th December 2017, 07:11 AM   #336
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Originally Posted by Craig B View Post
How can you know that? It will spread if it has the opportunity to spread, like every other natural entity. It is not a supernatural force with a predetermined destiny.
Sure, if all life on both continents is extinguished before they come together, there won't be anything to spread. I doubt that will happen, but it's possible. I'm not sure what the time frame is, but I think we're talking tens to hundreds of millions of years. That's shorter than, but approaching, the time at which the sun will be much hotter than it is today and may make the earth uninhabitable. In that case then, yeah, life won't spread.

On the other hand, if it's still around it will spread from one continent to the other, simply because there's nothing to stop it. We certainly have evidence that it has happened many times in the past.

But anyway, my point is simply that it's possible to spread to other stars by waiting for them to come to us, and in the same way to spread to the Andromeda galaxy. Yes, this presupposes that we have some sort of descendants hundreds of millions or billions of years from now. If we die out before Andromeda arrives, obviously we won't be going there.

But I don't think it's impossible for some form of our descendants to be around billions of years from now. After all, our ancestors were around billions of years ago.
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Old 6th December 2017, 06:53 AM   #337
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My understanding of how to get around the FTL requirement is by utilizing a means of folding space, which is theoretically possible, and is naturally occurring. We wouldn't actually move anywhere, the destination would come to us instead.
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Old 6th December 2017, 08:22 AM   #338
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Originally Posted by Jodie View Post
My understanding of how to get around the FTL requirement is by utilizing a means of folding space, which is theoretically possible, and is naturally occurring. We wouldn't actually move anywhere, the destination would come to us instead.
Every model that allows some form of faster than light travel requires something that we have no reason to believe exists in this universe.

While the possibility isn't entirely ruled out, we really have no reason to believe that it is actually possible either. And the fact that faster than light travel implies the ability to travel to the past, which has major issues for causality, I think chances are that it really will turn out to be impossible.
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Old 6th December 2017, 08:47 AM   #339
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Originally Posted by Jodie View Post
My understanding of how to get around the FTL requirement is by utilizing a means of folding space, which is theoretically possible, and is naturally occurring. We wouldn't actually move anywhere, the destination would come to us instead.
And also, your understanding of spacetime wormholes is that they are essentially the same kind of phenomenon as electromagnetic wave cancellation.

But okay, fine. Whatever. Based on your current understanding of FTL, what research is being done right now for the creation of wormholes?
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Old 6th December 2017, 09:28 AM   #340
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Originally Posted by Jodie View Post
My understanding of how to get around the FTL requirement is by utilizing a means of folding space, which is theoretically possible, and is naturally occurring. We wouldn't actually move anywhere, the destination would come to us instead.
Can you give a real example of a natural occurrence of folded space?
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Old 6th December 2017, 01:08 PM   #341
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Originally Posted by Jodie View Post
My understanding of how to get around the FTL requirement is by utilizing a means of folding space, which is theoretically possible, and is naturally occurring. We wouldn't actually move anywhere, the destination would come to us instead.
Folding of spacetime does not occur naturally. Spacetime curves due to mass and energy which are both naturally positive as far as we have determined. The curvature is one-way and so we get gravitational wells, i.e. not a fold. To get a fold we need to also have opposite curvature. Thus the word negative in the requirements for a traversable wormhole: "exotic matter with negative energy density or a negative mass cosmic string". Ditto for the FTL Alcubierre drive that needs negative mass.
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Old 6th December 2017, 01:26 PM   #342
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Originally Posted by Reality Check View Post
Folding of spacetime does not occur naturally. Spacetime curves due to mass and energy which are both naturally positive as far as we have determined. The curvature is one-way and so we get gravitational wells, i.e. not a fold. To get a fold we need to also have opposite curvature. Thus the word negative in the requirements for a traversable wormhole: "exotic matter with negative energy density or a negative mass cosmic string". Ditto for the FTL Alcubierre drive that needs negative mass.
What's hilarious is that if Jodie actually knew the first thing about "wormhole" research, she would have started with Alcubierre cites and other cites of sources from the article you linked.
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Old 7th December 2017, 07:16 PM   #343
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Originally Posted by Roboramma View Post
But I don't think it's impossible for some form of our descendants to be around billions of years from now. After all, our ancestors were around billions of years ago.
Our ancestors who were around billions of years ago are also the ancestors of today's sea anemones and oak trees, among other organisms.
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Old 7th December 2017, 08:44 PM   #344
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Originally Posted by Craig B View Post
Our ancestors who were around billions of years ago are also the ancestors of today's sea anemones and oak trees, among other organisms.
Of course. Does that have any bearing on anything I said?
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Old 9th December 2017, 07:25 PM   #345
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Originally Posted by theprestige View Post
You're just trying to rescue your wrong claim that wormhole research was currently under way.
It was in response to the comment regarding exotic matter. At any rate if a Nobel prize for some groundbreaking research on exotic matter doesn't prove my point then nothing will. You don't start from the finish line and work your way back.
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Old 9th December 2017, 07:38 PM   #346
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Originally Posted by Jodie View Post
It was in response to the comment regarding exotic matter. At any rate if a Nobel prize for some groundbreaking research on exotic matter doesn't prove my point then nothing will. You don't start from the finish line and work your way back.
Do you google words with no understanding of what they mean?
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Old 9th December 2017, 07:47 PM   #347
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Originally Posted by Reality Check View Post
Folding of spacetime does not occur naturally. Spacetime curves due to mass and energy which are both naturally positive as far as we have determined. The curvature is one-way and so we get gravitational wells, i.e. not a fold. To get a fold we need to also have opposite curvature. Thus the word negative in the requirements for a traversable wormhole: "exotic matter with negative energy density or a negative mass cosmic string". Ditto for the FTL Alcubierre drive that needs negative mass.
So I suppose the planets in our solar system aren't affecting the space they inhabit and near by objects? They are bending space causing it to curve. Black holes would be no different except the curve is more acute i.e. a fold.
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Old 9th December 2017, 08:53 PM   #348
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Originally Posted by Jodie View Post
It was in response to the comment regarding exotic matter. [...]
Cite? Didn'tThinkSo.
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Old 9th December 2017, 09:07 PM   #349
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Originally Posted by Roboramma View Post
Of course. Does that have any bearing on anything I said?
Yes.
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Old 9th December 2017, 10:20 PM   #350
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Originally Posted by Craig B View Post
Yes.
Could you perhaps clarify what?

I'll try to unpack what you are saying myself so that hopefully you don't think I'm being intentionally dense here:

The OP question is will humans ever explore other galaxies. If wait 4 billion years for the Andromeda galaxy to arrive here, whatever it is that will explore it won't be humans, so the answer to the OP is still no. That's reasonable, but I still think there's a difference between our descendants exploring Andromeda 4 billion years from now and no one doing so.

The other issue is that, as you point out, those descendants, if they exist, won't be just not human, they will likely be as different from us as we are from the archaea (primordial bacteria). I think that's true in some sense and not in others. Just as we share certain characteristics (like the coding of our DNA) with bacteria, those descendants will likely share certain characteristics with us. While they will certainly be extremely different in many ways those shared characteristics may be things we find more important than the ones that are different. For instance I would suspect that they will be intelligent and capable of communication with other beings.
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Old Yesterday, 01:23 AM   #351
Brainache
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Originally Posted by Roboramma View Post
Could you perhaps clarify what?

I'll try to unpack what you are saying myself so that hopefully you don't think I'm being intentionally dense here:

The OP question is will humans ever explore other galaxies. If wait 4 billion years for the Andromeda galaxy to arrive here, whatever it is that will explore it won't be humans, so the answer to the OP is still no. That's reasonable, but I still think there's a difference between our descendants exploring Andromeda 4 billion years from now and no one doing so.

The other issue is that, as you point out, those descendants, if they exist, won't be just not human, they will likely be as different from us as we are from the archaea (primordial bacteria). I think that's true in some sense and not in others. Just as we share certain characteristics (like the coding of our DNA) with bacteria, those descendants will likely share certain characteristics with us. While they will certainly be extremely different in many ways those shared characteristics may be things we find more important than the ones that are different. For instance I would suspect that they will be intelligent and capable of communication with other beings.
I don't think there is any reason to believe that anything living on Earth several billion years from now will be descended from Human Beings. They might be descended from cockroaches or squids or something...
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Old Yesterday, 01:41 AM   #352
Roboramma
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Originally Posted by Brainache View Post
I don't think there is any reason to believe that anything living on Earth several billion years from now will be descended from Human Beings. They might be descended from cockroaches or squids or something...
It's possible that we will go extinct, but I think our technology makes us the most likely organism on this planet to be able to thrive in whatever new environments present themselves and perhaps to move into environments off this world.

Cockroaches are certainly quite adaptable, but their abundance in the world today is due in large part to their ability to adapt to human-produce environments. Is there another species on this planet that has adapted itself to more environments than we have? Our technology is only continuing to progress at present and our ability to adapt to more and more severe environments continues.

The species most prone to extinction tend to be those limited to restricted ranges, or specialising in particular habitats or on particular food sources. We are about as far from that as it's possible to be.

Again, it's certainly possible that conditions could change enough that we go extinct and all future life is descended from something living around an undersea vent or something, but I think we are a robust enough lifeform that I wouldn't predict our extinction soon and I'd also predict that it will become more and more difficult to render us extinct as time passes (for instance: if we do being to colonize the solar system).
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Old Yesterday, 02:04 AM   #353
Craig B
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I don't think that "humans exploring other galaxies" covers the concept of organisms still being around in several billion years when Andromeda finally merges with our home galaxy. There won't be a seprate galaxy to explore, and the entities doing it may be descended from cockroaches, and all they will have to do is travel from star to star within a merged elliptical galaxy: nor do we know if conditions in such a galaxy will permit such journeys.
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Old Yesterday, 02:18 AM   #354
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Originally Posted by Craig B View Post
I don't think that "humans exploring other galaxies" covers the concept of organisms still being around in several billion years when Andromeda finally merges with our home galaxy. There won't be a seprate galaxy to explore, and the entities doing it may be descended from cockroaches, and all they will have to do is travel from star to star within a merged elliptical galaxy: nor do we know if conditions in such a galaxy will permit such journeys.
I think we understand the conditions in such a galaxy pretty well. Our own galaxy is the product of many past mergers. Further, a galaxy is a collection of stars, gas, dust, rocks, etc. The fact that it has merged with the Milky Way doesn't mean that it won't be those stars (etc.) being explored.

I also agreed that our descendants won't be human and in that sense, in this scenario, the answer to the OP question is no. I think that's a relatively trivial objection, however, given that the exploration will still be occurring. Even if the explorers are robots I'd still consider the OP's question to be answered "yes" in spirit.

Finally if you are positing that we leave no descendants to do that exploration (you say "the entities doing it may be descended from cockroaches") that's fine, I agree it's entirely possible. But the issue was whether the converse, that we do have such descendants, is possible. I still think it is, and relatively likely too. If you disagree with that feel free to address my last post.
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Old Yesterday, 02:59 AM   #355
Craig B
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Originally Posted by Roboramma View Post
I think we understand the conditions in such a galaxy pretty well. Our own galaxy is the product of many past mergers. Further, a galaxy is a collection of stars, gas, dust, rocks, etc. The fact that it has merged with the Milky Way doesn't mean that it won't be those stars (etc.) being explored..
PhysOrg has an article stating that mergers with small galaxies are different from collisions between large ones. In the latter case
In a galaxy collision, large galaxies absorb smaller galaxies entirely, tearing them apart and incorporating their stars. But when the galaxies are similar in size – like the Milky Way and Andromeda – the close encounter destroys the spiral structure entirely. The two groups of stars eventually become a giant elliptical galaxy with no discernible spiral structure.
Such interactions can also trigger a small amount of star formation. When the galaxies collide, it causes vast clouds of hydrogen to collect and become compressed, which can trigger a series of gravitational collapses. A galaxy collision also causes a galaxy to age prematurely, since much of its gas is converted into stars.
That sounds very nasty, even though the probability of even one direct stellar collision between the Milky Way's 300 billion and Andromeda's trillion stars is very low, so great are the distances between individual stars. https://phys.org/news/2016-10-galaxies-collide.html
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Old Yesterday, 06:40 AM   #356
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Originally Posted by Craig B View Post
PhysOrg has an article stating that mergers with small galaxies are different from collisions between large ones. In the latter case
In a galaxy collision, large galaxies absorb smaller galaxies entirely, tearing them apart and incorporating their stars. But when the galaxies are similar in size – like the Milky Way and Andromeda – the close encounter destroys the spiral structure entirely. The two groups of stars eventually become a giant elliptical galaxy with no discernible spiral structure.
Such interactions can also trigger a small amount of star formation. When the galaxies collide, it causes vast clouds of hydrogen to collect and become compressed, which can trigger a series of gravitational collapses. A galaxy collision also causes a galaxy to age prematurely, since much of its gas is converted into stars.
That sounds very nasty, even though the probability of even one direct stellar collision between the Milky Way's 300 billion and Andromeda's trillion stars is very low, so great are the distances between individual stars. https://phys.org/news/2016-10-galaxies-collide.html

Yeah, the violent imagery of merging/colliding galaxies, with words like "tearing apart" and "destroyed" and "chaotic," apply only on a ridiculously compressed time scale.

It's like looking at plate tectonics and imagining that everyone living on the earth must be constantly running for their lives to avoid being suddenly pulled into subduction zones.
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Old Yesterday, 06:56 AM   #357
Craig B
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Originally Posted by Myriad View Post
Yeah, the violent imagery of merging/colliding galaxies, with words like "tearing apart" and "destroyed" and "chaotic," apply only on a ridiculously compressed time scale.

It's like looking at plate tectonics and imagining that everyone living on the earth must be constantly running for their lives to avoid being suddenly pulled into subduction zones.
Only by a fantastic compression of timescales can anyone interpret the merger of Andromeda and the Milky Way as permitting a form of intergalactic voyaging. It's like looking at plate tectonics closing the Pacific Ocean and saying, now, that's a good way of travelling to Hawaii!
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Old Yesterday, 08:51 AM   #358
Roboramma
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Originally Posted by Craig B View Post
Only by a fantastic compression of timescales can anyone interpret the merger of Andromeda and the Milky Way as permitting a form of intergalactic voyaging. It's like looking at plate tectonics closing the Pacific Ocean and saying, now, that's a good way of travelling to Hawaii!
It's funny that you are using the same analogy again and yet haven't actually discounted the fact that it works.

That may not be how life got to Hawaii, but for instance much of South America's fauna arrived there when it merged with North America, and many of it's prior inhabitant went extinct due to that interaction.
https://en.wikipedia.org/wiki/Great_...an_Interchange
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Old Yesterday, 09:05 AM   #359
Craig B
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Originally Posted by Roboramma View Post
It's funny that you are using the same analogy again and yet haven't actually discounted the fact that it works.

That may not be how life got to Hawaii, but for instance much of South America's fauna arrived there when it merged with North America, and many of it's prior inhabitant went extinct due to that interaction.
https://en.wikipedia.org/wiki/Great_...an_Interchange
It's not how life got to Hawaii, and it's not how life got to S America either. Nor is it relevant to humans exploring other galaxies. When our galaxy merges with Andromeda there won't be two galaxies. Only one combined galaxy.
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Old Yesterday, 09:08 AM   #360
Roboramma
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Originally Posted by Craig B View Post
It's not how life got to Hawaii, and it's not how life got to S America either.
It's certainly how much of the life in South America got there. Do you deny that? The fact that there was already some life there prior to that doesn't change that fact.

Quote:
Nor is it relevant to humans exploring other galaxies. When our galaxy merges with Andromeda there won't be two galaxies. Only one combined galaxy.
What is now Andromeda may be explored by our descendants.
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