As real as math
In the most scientific way possible, there’s no way these could affect our own. If they did, we’d consider that mechanism part of our universe. Real possibility - of course it’s real. There’s just absolutely no way to know, even if you made the question a lot more specific. (What does it mean, specifically? What would you expect to see if it were true vs false?)
Max Tegmark came up with different “levels” of multiverse, and the first level only depends on the universe (not just observable) being infinitely large in volume - which as I understand it seems likely to be the case. (Certainly hasn’t been ruled out at least)
Given infinite space with accompanying infinite matter/energy, there will be infinite repeats and near repeats of the stuff in any given volume of space - the volume of the observable universe for example, meaning us and everything we can interact with (even just see) is repeated infinite times, and with all physically possible variations.
And that’s without any particular interpretation of quantum mechanics.
dang, cosmology is weird. I went to reply about the big bang, the age of the universe, and how it can’t be infinite, but instead decided to look it up. I really don’t understand this stuff.
Not everyone in this comment section uses correct nomenclature. It would be preferable for those bugged by it to use empathy to understand the true meaning of the comments (or, if impossible, to ask politely about the meaning) and to correct the mistakes in a nice way, avoiding the urge to take the wrong words litterally - that doesn’t add to the discussion.
Hopefully that can be the case in one of the multiverses. I doubt it will be this one.
You mean I shouldn’t react emotionally and impulsively because I disagree and feel personally offended by the first sentence in your comment?
You might enjoy this recent lecture from Neil Turok: https://youtu.be/rsI_HYtP6iU
Over the past decade or so he’s been putting out papers with a model that’s only a slight change to the standard model - that at the point of the big bang there was an expansion in both directions of time leading to a CPT symmetric universe.
He and his coauthors have managed to address a number of the major outstanding unsolved challenges in cosmology with only this theory, and are perhaps only a few years away from having some of its testable predictions verified. And at least one of the recent CERN projects that would have falsified the idea came up short just the other year.
If he lives long enough, he may well end up with a Nobel for his efforts.
It’s probably my favorite bit of theoretical cosmology these days.
According to the many worlds interpretation of quantum physics there’s not only alternative universes, but that there’s an infinite amount of them including ones exactly like this one with just slight variations.
As in the classic theory idea, that each time a decision is made a new reality is created for each choice? For it to be possible would break our fundamental laws regarding conservation of mass and energy. Where would this alternative universe get all that energy and mass from? It’s possible our current understanding of the law is inaccurate, but it’s extremely unlikely.
Where did all the energy in the universe come from? This is not physics, it’s methaphysics. We are talking about things that are outside our knowledge and science is descriptive, not prescriptive. Extrapolations must be tested. This is not much different from saying that the most remote galaxies receding at speeds faster than light is impossible, because nothing can travel faster than light. Maybe it’s just matter that can’t break that rule, while space itself can expand at whatever speed, or maybe it’s just an error somewhere in our assumptions. We still don’t know. But we DO think they are receding faster than light.
This video from PBS Space Time is a good summary of the current state of science on this topic. https://youtu.be/z-syaCoqkZA?si=nRK78T_FAD5By-f0
I like Neil Degrasse Tyson’s take on this one. At first we thought there was only one Sun, then we figured out the sun was a star, like so many others. Then we thought there was only one galaxy, then we figured there are much more than that.
Now we think there is only one universe, but it seems nature isn’t very good at creating only one version of something. It’s not unreasonable to think there are many universes. We just can’t prove/observe it yet.
https://youtu.be/1jmNzlTd09E?si=5w486YFlK4IbqpmK
Watch this^^^^^^
There are different levels of multiverse that are logically possible with our current understanding of physics.
It’s incredible to think about.
I honestly think that whatever soup we’re all swimming in, it’s just one big soup. There are not multiple soups. There are multiple solar systems and multiple galaxies within the soup, but it’s just one big universe. We cannot fathom how big the universe is or if it’s infinite or even if the universe is an infinitely massive sphere.
That’s how I picture it. One big infinitely massive spherical universe.
But If it’s infinite, how can it be a sphere?
I dunno, some things are too massive for us to comprehend.
There are multiple solar systems
There’s only one solar system in the universe.
Reference: https://science.nasa.gov/solar-system/facts/
I’m confused, are you saying there’s only one solar system because we’ve only really named our planetary system the “solar system” ?
Not to be rude but that seems pedantic because there’s more than one definition and according to Merriam Webster
solar system noun: the sun together with the group of celestial bodies that are held by its attraction and revolve around it also : a similar system centered on another star
Meanwhile, elsewhere on the same site, over here https://spaceplace.nasa.gov/other-solar-systems/en/ says:
Our solar system is just one specific planetary system—a star with planets orbiting around it. Our planetary system is the only one officially called “solar system,” but astronomers have discovered more than 3,200 other stars with planets orbiting them in our galaxy.
Genuinely curious to learn as I do not know a lot about this stuff and feel like I am missing something?
This is a case of a term that was until recently specific but is now becoming a more general term.
While planets orbiting other stars has been talked about for centuries, it is only in the past few decades that we have been able to confirm their existence.
So, up until then Solar system was a term that described our solar system as it was the only one known to exist.
There’s only one solar system in the universe as it is the system of Sol (the Sun), our local star.
Other terms such as solar mass, solar wind, solar nebula, solar atmosphere, and solar flare likewise relate to Sol.
Yes, there’s only one solar system in the universe as it is the system of Sol (the Sun), our local star.
Other terms such as solar mass, solar wind, solar nebula, solar atmosphere, and solar flare likewise relate to Sol.
In addition to what everyone else has already said, consider this: the “Universe” is by definition everything that exists. There cannot “be” things which do not exist. Therefore the question cannot be answered because it presupposes something could exist which is not part of the universe.
That’s a philosophical answer, not a scientific one.
No, it’s a logical answer. The definition of the word universe is “everything that exists”
Edit: this is really just another way of expressing that the hypothesis isn’t testable. If something could be measured which could validate or falsify the hypothesis, then that thing being measured would have to exist, and therefore has to be part of the universe.
So a multiverse can’t exist because it doesn’t match a Webster’s Dictionary definition or did you just not understand the question?
The question makes no sense because the terms aren’t well-defined. It’s like asking “are there other sets of integers besides the ones we know about?” There’s only one set of all integers. We know what the integers are by definition. If something looks like an integer, it is an integer. Similarly, you can’t ask about the existence of something which is not part of the universe, because if something exists, it is part of the universe.
The “Many Worlds” interpretation of quantum mechanics proposes that there are other universes separate from our own, perhaps even an incredible number of them if there’s one for every quantum interaction.
It’s consistent with our mathematical understanding of reality. But scientifically, it’s still an open question on whether the hypothesis is testable or whether those other potential universes will ever be observable. https://youtu.be/z-syaCoqkZA?si=5_KJB2rcscjhD9_e
