A possible world is a logical structure. A system, or world, that is governed by a rule.

As current theory of multiple worlds in quantum physics goes, different possibilities for the universe exist simultaneously. — Jackson

Yes, and?

But the initial state of the universe is unique in this picture. The MWI was introduced to ensure unitarity in QM, during an interaction, which is just a mathematical necessity imposed on the world which doesn't have to hold physically. It's conceivable that a wavefunction collapses non-unitarily in a different interpretation of the wavefunction collapse.

Infinitely many inital worlds are not contained in this MWI.

Yes, and? — Haglund

And monads.

What are you talking about?

I don't believe in possible worlds. I believe in Toity worlds. Have you read Toity Worlds by Prof. Boule Sheet?

Prof. Sheet distinguishes between two kinds of truth: hoity truths and toity truths.

What's a toity truth? Well, a toity truth, Prof. Sheet tells us, is a truth that is true in at least one toity world.
What's a hoity truth? A hoity truth is a truth that is true in 'all' toity worlds.

What's a toity world? Well, it's just a device to make clearer what a toity truth is.

Interesting.

I don't believe in possible worlds. I believe in Toity worlds. Have you read Toity Worlds by Prof. Boule Sheet?

Prof. Sheet distinguishes between two kinds of truth: hoity truths and toity truths.

What's a toity truth? Well, a toity truth, Prof. Sheet tells us, is a truth that is true in at least one toity world.
What's a hoity truth? A hoity truth is a truth that is true in 'all' toity worlds.

What's a toity world? Well, it's just a device to make clearer what a toity truth is. — Bartricks

When I was 8 old I found this to be funny. Not since then.

What's a toity world? Well, it's just a device to make clearer what a toity truth is. — Bartricks

It's refreshing that, having assumed all avenues of original philosophical exploration had been traveled, something novel and appealing bubbles up from spilled beer at the local bar. :strong:

Then you are as lacking in humour as you are in insight. Substitute 'possible' for 'toity' and 'necessary' for 'hoity' and then see if that produces any mirth in you.

Then you are as lacking in humour as you are in insight. Substitute 'possible' for 'toity' and 'necessary' for 'hoity' and then see if that produces any mirth in you. — Bartricks

If you don't like philosophy, try posting on a chit chat site.

I'm a philosopher.

Now, what do you understand a possible world to be? And can you distinguish one from a toity world?

Now, what do you understand a possible world to be? And can you distinguish one from a toity world? — Bartricks

Goodbye.

That makes no sense.

Come on - what's a possible world and how is one different from a toity world?

A possible world is a logical structure. A system, or world, that is governed by a rule. — Jackson

The logical structure itself is made by us. In one side, we have a world or "universe" and, in the other side, we the humans make an order to live on those structures. We do not really know yet how many x universes or worlds exist with our same logical structure. I think this is due to that the term "logic" is something we created. The universe exists itself, "it" doesn't care about how many logic worlds are on it

Now, what do you understand a possible world to be? And can you distinguish one from a toity world? — Bartricks

I have to admit, you got humour! :lol:

Two very different things with a similar name. Modal possible worlds, the sort Leibniz discussed, are used to discuss problems in modal logic. The many-worlds interpretation of QM is used to solve problems in physics.

They are worlds apart.

Two very different things with a similar name. Modal possible worlds, the sort Leibniz discussed, are used to discuss problems in modal logic. The many-worlds interpretation of QM is used to solve problems in physics. — Banno

Small minds think small thoughts.

But you and I can do better...

Did you peruse the links to SEP articles on each?

And monads. — Jackson

What about them? Can't monads exist in many worlds? Nomads travel between them. Monads stay in one.

One is not immortal in the MWI. At one branching point one encounters a superposition of death. The so-called death collapse.

What about them? Can't monads exist in many worlds? Nomads travel between them. Monads stay in one. — Haglund

Nomads?

Did you peruse the links to SEP articles on each? — Banno

Stop misquoting me. It is wrong.

What about them? Can't monads exist in many worlds? Nomads travel between them. Monads stay in one.
— Haglund

Nomads? — Jackson

Nomads travel from world to world, like the Roma on that beautiful painting of van Gogh. What color, light and atmosphere! Monads, on the other hand, are stuck in a category, in one world. If there are many parallel worlds, like in the MWI, what determines you find yourself in this particular one? Which is only particular in the context of the others. How can we ever know there are other worlds?

There couldn't have existed a world in which the airplane above the city flew on a different line, while everything else is the same. Such a world can't come to be after a next big bang. Out of the question, I might humbly add.