Whether you need a new villain or an old Spider-Man, your science fiction movie will sound more respectable from a scientific point of view if you use the word multiverse. Marvel’s multiverse puts different versions of our “out there somewhere” universe. In these films, with the right combination of technology, magic and imagination, travel between these universes is possible.
For example (spoilers!), C Spider-Man: No way home, we find that there are other universes and other Earths, some of which have their own local Spider-Man. In the universe of film, magic is possible.
This magic, thanks to an improper spell by superhero Dr. Strange, causes some of the other Spider-Man to be transported to our universe, along with several supervillains.
IN Dr. Strange in the multiverse of madness (in theaters this week) The rogue universe on the universe threatens to “desecrate reality.”
So which of these ideas did Marvel borrow from science and which are pure fiction?
Multiverse lite: a really big universe
Could there be other lands? Could there be other people who look a lot like us, on a planet that looks like ours? It is scientifically possible because we do not know how big our universe really is.
We can see billions of light years in space, but we don’t know how much more space there is beyond what we can see.
If there is more space outside, full of galaxies, stars and planets, then there are more and more chances for the existence of another Earth. Somewhere. With enough space and enough planets, any possibility becomes possible.
The invention of Marvel’s multiverse stems from the ability to travel between these other lands. There is a good reason why Dr. Strange should use magic for this.
According to Albert Einstein, we cannot travel in space faster than light. And while more exotic ways to travel the universe are scientifically possible – wormholes, for example – we don’t know how to make them, the universe doesn’t seem to make them naturally, and there’s no reason to think you connect us to another Earth, not to any random part of the empty space.
So, almost certainly, if the Other Earth is somewhere out there, it is unimaginably far away, even for an astronomer.
Changing the laws of nature
Marvel’s multiverse may look wild, but from a scientific point of view it’s actually too meek. Too normal. Too familiar. That’s why.
The main building blocks of our universe – protons and neutrons (and their quarks), electrons, light, etc. – are able to create amazing things, such as human life. Your body is amazing: it collects energy, processes information, mini-engineering, self-healing.
physicists have discovered that the ability of the building blocks of our universe to create life forms is extremely rare. It’s just that all the old blocks don’t work.
If the electrons were too heavy or the force that held the atomic nuclei together was too weak, the matter of the universe would not even stick together, let alone do something as beautiful as a living cell. Or, really, whatever this can be called alive.
How did our universe get the right combination of ingredients? Maybe we won the space lottery. Perhaps on a scale much larger than what our telescopes can see, other parts of the universe have different building blocks.
Our universe is just one of the options – especially happy – among many universes with lost tickets.
This is the scientific multiverse: not just more than our universe, but universes with different fundamental components. Most are dead, but very rarely is the right combination of life forms.
Marvel’s multiverse, in contrast, simply rearranges the familiar atoms and forces of our universe (plus a little magic). This is not enough.
Cosmic inflation and the Big Bang
What has our universe been like in the past? Evidence suggests that the universe was hotter, denser and smoother. This is called The Big Bang Theory.
But was there a Big Bang? Was there a time when the universe was infinitely hot, infinitely dense, and contained at one point? Okay maybe. But we’re not sure, so scientists have explored a bunch of other possibilities.
An idea called space inflation, says that in the first part of a second the universe expanded extremely fast. If true, that would explain a few things about why our universe is expanding exactly the way it does.
But how do you make a universe expand so fast? The answer is a new type of energy field. It controls the first moments of the universe, causes rapid expansion and then transmits the reins to the more familiar forms of matter and energy: protons, neutrons, electrons, light, etc.
Cosmic inflation can create a multiverse. This is how. According to this idea, most of the space expands, inflates, doubles in size, from moment to moment. Spontaneously and arbitrarily, on small islands, the new energy field transforms its energy into ordinary matter with extremely high energies, releasing what we now see as the Big Bang.
If these high energies mix and reset the basic properties of matter, then each island can be considered as a new universe with different properties. We created a multiverse.
So is there a Multiverse?
In the cycle of the scientific method, the multiverse is in a research phase. We have an idea that can explain a few things if it was true. That makes it worthy of our attention, but it’s not quite science yet. We need to find evidence that is more direct, more decisive.
Something left over from the effects of the multiverse generator could help. The idea of a multiverse can also predict the winning numbers in our lottery ticket.
However, as Dr. Strange explains, “The multiverse is a concept we know frighteningly little about.”