Multiverse Question

[Teallaura]

Hi, me again! No, not debating, I really just want an answer - although I concede I suspect that it depends on who you ask (not in a bad way, just that it's not firmly established).

Okay, so the multiverse - is it supposedly existent at all three levels of scale: infinitesimal, macro, infinite? My understanding is that it primarily answers issues at the infinitesimal and just because a quark can have infinite possibilities does not mean the table it belongs to also has infinite possibilities (until the collapse, of course).

Sci Fi operates under the assumption that the multiverse exists at the macro and (probably) the infinite as well. So there is a dimension out there that has Earth populated by blue unicorns who all speak Klingon. Great stories result - but is this a valid representation of the theory?

Thanks in advance!

Oh, and if you want to post links, remember I'm a layman - my days as a physics student were short and long, long ago...

[Sea of red]

The speculation you speak of comes from the combining of two areas of... speculation.

One is the of 'many worlds interpretation' of QM by Hugh Everett, which postulates that each quantum state is representative of an alternative history occurring in a larger universe. Some have speculated that it means 'anything goes' in this domain, leading to some absurd conclusions such as each of us having a history where we are president (), etc,. The metaphysical conclusions get really silly, really fast.

The other is the anthropic landscape. This postulates that the universe is actually a larger domain of 'pocket universes' (PU) where the constants of nature vary greatly, leading to different environments. String theory and cosmic inflation are the basis to these ideas, and while there is some evidence to support inflation, we really don't understand it all that well. String theory is a mangled mess of esoteric mathematics, and has gone nowhere in forty years. There are good reasons for taking the idea seriously, but we're nowhere near confirming - plus alternatives do exist.

Here's a good rundown of the situation.

The Multiverse: Big Bangs Without End



http://www.skyandtelescope.com/astro...s-without-end/

Cheers.

[Teallaura]

Thanks!

[Sea of red]

No problem.

[psstein]

Yes and no, it depends what "type" of multiverse you hold to. David Deutsch suggests four different types:

1. None

2. One in which there is more of a universe than accessible to current instruments (this is what I subscribe to)

3. One in which there are separate universes, similar to our own.

4. One in which the physical constants greatly vary among multiverses.

[oxmixmudd]

The wikipedia article has a bit more information on the possible types of multiverses based on current theories. I'm just going to quote the section here.

for the entire article, see https://en.wikipedia.org/wiki/Multiverse

Source: wikipedia multiverse article

Brian Greene's nine types
The American theoretical physicist and string theorist, Brian Greene, discussed nine types of parallel universes:[64]
Quilted
The quilted multiverse works only in an infinite universe. With an infinite amount of space, every possible event will occur an infinite number of times. However, the speed of light prevents us from being aware of these other identical areas.
Inflationary
The inflationary multiverse is composed of various pockets in which inflation fields collapse and form new universes.
Brane
The brane multiverse version postulates that our entire universe exists on a membrane (brane) which floats in a higher dimension or "bulk". In this bulk, there are other membranes with their own universes. These universes can interact with one another, and when they collide, the violence and energy produced is more than enough to give rise to a big bang. The branes float or drift near each other in the bulk, and every few trillion years, attracted by gravity or some other force we do not understand, collide and bang into each other. This repeated contact gives rise to multiple or "cyclic" big bangs. This particular hypothesis falls under the string theory umbrella as it requires extra spatial dimensions.
Cyclic
The cyclic multiverse (via the ekpyrotic scenario) has multiple branes (each a universe) that have collided, causing Big Bangs. The universes bounce back and pass through time until they are pulled back together and again collide, destroying the old contents and creating them anew.
LandscapeQuantum
The quantum multiverse creates a new universe when a diversion in events occurs, as in the many-worlds interpretation of quantum mechanics.
Holographic
The holographic multiverse is derived from the theory that the surface area of a space can simulate the volume of the region.
Simulated
The simulated multiverse exists on complex computer systems that simulate entire universes.
Ultimate
The ultimate multiverse contains every mathematically possible universe under different laws of physics.

© Copyright Original Source

It's all very much speculative at this point, though in theory there may be ways to get hints as to whether or not they are out there.

There was an article aimed at layman descibing a conundrum that might point to such a thing: a 'cold spot' in the CMB

https://futurism.com/new-evidence-ab...-a-multiverse/

and here:

http://www.telegraph.co.uk/science/2...t-space-could/

Another intriguing varient is the simulation universe which basically blew Tassman's mind. Nevertheless, it is one of the possible types of universes in the multiverse that has a least some serious representation. Nick Bostrom at Oxford has published some papers on the idea and seems to be pushing it as a serious possibility.

http://www.simulation-argument.com/matrix.html

The other one I find interesting is the holographic universe, where we 'really' are simply existing on a 2-D hologrphic surface:

https://phys.org/news/2017-01-reveal...-universe.html

It's all very fantastic stuff, but there are serious scientists doing serious work on these ideas and astronomers and physicists are keeping their eyes open for hints one of them might have observable evidence.

JIm

[Teallaura]

OOOOHHHH!!!!! Thanks guys!!!!!!

[Sparko]

I want to go live in the Star Trek universe.

[37818]

I want to go live in the Star Trek universe.

Jeremiah 31;37,
Thus saith the LORD; If heaven above can be measured, and the foundations of the earth searched out beneath, I will also cast off all the seed of Israel for all that they have done, saith the LORD.

[rossum]

I want to go live in the Star Trek universe.

Sorry, no room there, it's full of Tribbles. You need the Star Trek2 universe, the one without Tribbles.

rossum

[Sparko]

Sorry, no room there, it's full of Tribbles. You need the Star Trek2 universe, the one without Tribbles.

rossum

I was hoping for the Star Trek the New Generation Universe. More modern.

[rogue06]

I was hoping for the Star Trek the New Generation Universe. More modern.

You could take your cell phone with you to the original one and use it to "modernize" their communicators. With your luck if you went to the STNG universe you'd end up on a planet being assimilated by the Borg.

[Sparko]

You could take your cell phone with you to the original one and use it to "modernize" their communicators. With your luck if you went to the STNG universe you'd end up on a planet being assimilated by the Borg.

Do they have wi-fi?

[Sparko]

You could take your cell phone with you to the original one and use it to "modernize" their communicators. With your luck if you went to the STNG universe you'd end up on a planet being assimilated by the Borg.

In some other universe they are watching a TV show about an alternate history America that is run by celebrities and overrun by radical liberals who demand free speech be stopped and that eating tacos is racist.

[rossum]

You could take your cell phone with you to the original one and use it to "modernize" their communicators. With your luck if you went to the STNG universe you'd end up on a planet being assimilated by the Borg.

Nah. "Phasers on slaughter!"

rossum