Universes. Is one a sign of others?

[chezlaw]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
could be a multiverse is just a universe. There was talk of creating a universe in a lab, that would presumably be within this universe in some sense.

as long as its possible in theory for us to create universes then doesn't that measn that universes are nothing particularly special?

chez

[/ QUOTE ]
Perhaps it's definitional. I dont understand universe to include some subset of this universe (I dont even understand what "universe in a lab" means, it just seems a smaller part of our universe).

I thought luckyme was referring to other things like our physical universe but with, perhaps, differing physical laws - I dont see how it would be possible to create something within a laboratory which had a force of gravity proportional to the cube of the distance, for example. Nonetheless, if other universes are possible, perhaps one could exist which had this property (Not that it would be very interesting imo).

[/ QUOTE ]
this sort of thing

chez

[/ QUOTE ]
*shrug* If the laws of this "pocket universe" are necessarily the same as the laws in this one and if the matter inside it was previously in this one then it's not what I mean by "another" universe. I would think of it as a part of this universe, isolated from the rest. To me, a different universe has differing fundamental constants or laws than ours (at least potentially).

[/ QUOTE ]
So if we created two of these and someone like you lives in one and discovers the other he would be wrong to think he had discovered another universe (in your sense of the word universe).

chez

[Kaj]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
could be a multiverse is just a universe. There was talk of creating a universe in a lab, that would presumably be within this universe in some sense.

as long as its possible in theory for us to create universes then doesn't that measn that universes are nothing particularly special?

chez

[/ QUOTE ]
Perhaps it's definitional. I dont understand universe to include some subset of this universe (I dont even understand what "universe in a lab" means, it just seems a smaller part of our universe).

I thought luckyme was referring to other things like our physical universe but with, perhaps, differing physical laws - I dont see how it would be possible to create something within a laboratory which had a force of gravity proportional to the cube of the distance, for example. Nonetheless, if other universes are possible, perhaps one could exist which had this property (Not that it would be very interesting imo).

[/ QUOTE ]
this sort of thing

chez

[/ QUOTE ]
*shrug* If the laws of this "pocket universe" are necessarily the same as the laws in this one and if the matter inside it was previously in this one then it's not what I mean by "another" universe. I would think of it as a part of this universe, isolated from the rest. To me, a different universe has differing fundamental constants or laws than ours (at least potentially).

[/ QUOTE ]
So if we created two of these and someone like you lives in one and discovers the other he would be wrong to think he had discovered another universe (in your sense of the word universe).

chez

[/ QUOTE ]

I think by definition if you're in one universe, you can't "discover" the other.

[bunny]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
this sort of thing

chez

[/ QUOTE ]
*shrug* If the laws of this "pocket universe" are necessarily the same as the laws in this one and if the matter inside it was previously in this one then it's not what I mean by "another" universe. I would think of it as a part of this universe, isolated from the rest. To me, a different universe has differing fundamental constants or laws than ours (at least potentially).

[/ QUOTE ]
So if we created two of these and someone like you lives in one and discovers the other he would be wrong to think he had discovered another universe (in your sense of the word universe).

chez

[/ QUOTE ]
Yeah - he would have discovered a previously inaccessible part of the univers. Although I dont think this scenario is possible in the pocket universe suggested in the link you posted - they postulated that the pocket universe would be completely inaccessible to ours, so I dont see how they could "discover" ours. (Perhaps deduce it's existence somehow?)

[chezlaw]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
could be a multiverse is just a universe. There was talk of creating a universe in a lab, that would presumably be within this universe in some sense.

as long as its possible in theory for us to create universes then doesn't that measn that universes are nothing particularly special?

chez

[/ QUOTE ]
Perhaps it's definitional. I dont understand universe to include some subset of this universe (I dont even understand what "universe in a lab" means, it just seems a smaller part of our universe).

I thought luckyme was referring to other things like our physical universe but with, perhaps, differing physical laws - I dont see how it would be possible to create something within a laboratory which had a force of gravity proportional to the cube of the distance, for example. Nonetheless, if other universes are possible, perhaps one could exist which had this property (Not that it would be very interesting imo).

[/ QUOTE ]
this sort of thing

chez

[/ QUOTE ]
*shrug* If the laws of this "pocket universe" are necessarily the same as the laws in this one and if the matter inside it was previously in this one then it's not what I mean by "another" universe. I would think of it as a part of this universe, isolated from the rest. To me, a different universe has differing fundamental constants or laws than ours (at least potentially).

[/ QUOTE ]
So if we created two of these and someone like you lives in one and discovers the other he would be wrong to think he had discovered another universe (in your sense of the word universe).

chez

[/ QUOTE ]

I think by definition if you're in one universe, you can't "discover" the other.

[/ QUOTE ]
it's a hypothetical to help understand what bunny means.

chez

[luckyme]

[ QUOTE ]
*shrug* If the laws of this "pocket universe" are necessarily the same as the laws in this one and if the matter inside it was previously in this one then it's not what I mean by "another" universe. I would think of it as a part of this universe, isolated from the rest. To me, a different universe has differing fundamental constants or laws than ours (at least potentially).

[/ QUOTE ]

I was striving to be non-rigorous.
A different universe could be like identical twins or something with just enough features that we call it a universe. Not sure that 'inside this one' fits the concept of universe, but it's not crucial to how I think about it.
One test for this approach is that if CNN announced tomorrow- 'evidence of new universe found', I'd be more inclined to give an excited shrug and say "well, 'bout time." I wouldn't be surprised in the way somebody who was locked into the 'Uni' part of 'Universe'.

luckyme

[bunny]

[ QUOTE ]
I was striving to be non-rigorous.

[/ QUOTE ]
There's no point, doesnt DS consider you a lost cause?

[ QUOTE ]
A different universe could be like identical twins or something with just enough features that we call it a universe. Not sure that 'inside this one' fits the concept of universe, but it's not crucial to how I think about it.
One test for this approach is that if CNN announced tomorrow- 'evidence of new universe found', I'd be more inclined to give an excited shrug and say "well, 'bout time." I wouldn't be surprised in the way somebody who was locked into the 'Uni' part of 'Universe'.

luckyme

[/ QUOTE ]
I think I would shrug and say "Wow, it's bigger than we thought". Probably terminology though.

To go back to your original point though - dont you agree that the induction that one object/process is unlikely to be unique is at least partly justified by the properties of the universe the object occurs in? I dont think you would be as inclined to induce the likelihood of a similar object somewhere if we lived in a random, ever changing universe (and I realise how impossible that is to even imagine, I'm striving for nonrigorousness as well).

[luckyme]

[ QUOTE ]
To go back to your original point though - dont you agree that the induction that one object/process is unlikely to be unique is at least partly justified by the properties of the universe the object occurs in? I dont think you would be as inclined to induce the likelihood of a similar object somewhere if we lived in a random, ever changing universe (and I realise how impossible that is to even imagine, I'm striving for nonrigorousness as well).

[/ QUOTE ]

That touches on what I was attempting to tease apart with the OP - how much of this expectation is the human evolved conditioning and how much is objectively valid.
To reload - even in a much more random universe, why would the discovery of a structure or process demand the reaction, "ok, that's it, no way now there could be two of these types of things".
It would seem to be a very strange set of laws at work that would deny any similarity in output ( not impossible I 'spose, but I can't get my mind around the requirements ).

luckyme

[bunny]

[ QUOTE ]
[ QUOTE ]
To go back to your original point though - dont you agree that the induction that one object/process is unlikely to be unique is at least partly justified by the properties of the universe the object occurs in? I dont think you would be as inclined to induce the likelihood of a similar object somewhere if we lived in a random, ever changing universe (and I realise how impossible that is to even imagine, I'm striving for nonrigorousness as well).

[/ QUOTE ]

That touches on what I was attempting to tease apart with the OP - how much of this expectation is the human evolved conditioning and how much is objectively valid.
To reload - even in a much more random universe, why would the discovery of a structure or process demand the reaction, "ok, that's it, no way now there could be two of these types of things".
It would seem to be a very strange set of laws at work that would deny any similarity in output ( not impossible I 'spose, but I can't get my mind around the requirements ).

luckyme

[/ QUOTE ]
I dont think it would be right to conclude there's no way there'd be another such object. However, I dont think it would be right to conclude that another such object was now more likely either (unless you had a theorised process by which the observed object was produced and a hunch that the required initial state was likely to recur). I'm loathe to mention religion in a thread which has gone 20 or so posts without,[img]/images/graemlins/grin.gif[/img] yet it seems reminiscent of your atheism distinction - I dont think not believing there's another such object implies you believe there isnt another one.

In other words, I think it is a false dichotomy if you are suggesting "this must be unique" and "there's likely to be others" are the only options. I think, absent any information as to the cause (which is something you dont experience with any actual object you have encountered within our universe), the justified response is "we dont know if there are any other things like this".

[luckyme]

[ QUOTE ]
In other words, I think it is a false dichotomy if you are suggesting "this must be unique" and "there's likely to be others" are the only options. I think, absent any information as to the cause (which is something you dont experience with any actual object you have encountered within our universe), the justified response is "we dont know if there are any other things like this".

[/ QUOTE ]

It seems, "we dont know if there are any other things like this" is the position we're in prior to observing one ( we just imagined one with a "I wonder if it's possible" thought).

Having observed one, doesn't that increase the chance there are two or more compared to the pre-observation chance when we had observed zero?

Prior to observing one we would only have justification for believing A's were more likely than B's to exist if we had some idea about causation. Given equal ignorance of causation, once we observe one A, that is an argument in favor of other A's that imagined B doesn't have for B's.

I seem to operate on some "Uniqueness is very unique" viewpoint and can't shake the notion that observing an A raises "what would prevent another A from existing now we know they are possible". B seems to have " perhaps they are impossible to form" going against it which A has now escaped. That seems significant to me and more trivial to you ??

In the dichotomy corner - I wouldn't split it into "that's not possible" and "It must be possible". Rather that observation slides likelihood quite a long way up the scale from Impossible to Certain. Keeping in mind that conjured up possibles don't start at the extreme Impossible end.

thanks for helping. onward, thru the fog..., luckyme

[luckyme]

[ QUOTE ]
I'm loathe to mention religion in a thread which has gone 20 or so posts without, yet it seems reminiscent of your atheism distinction - I dont think not believing there's another such object implies you believe there isnt another one.

[/ QUOTE ]

To indulge your loathing -
There is a category 'Animal'.
Things that don't fit the shirt are Non-Animals.
That not all Non-Animals are identical does not reduce the purity of the statement "These are all Non-Animals".
It almost seems like the "No True Scotsman" fallacy to wiggle that one Non-Animal is less or more of a Non-Animal than the next if the only criteria for Non-Animal is that it 'ain't no Animal'.

It does relate to this thread because there are two groups of objects, "this Universe" and "Non-this Universes". To point out that there are differences between the various Non-this Universes doesn't alter the fact that "Non-this Universes" is a proper and distinct category.

luckyme