Multitasking

On Sunday night, Tar won the OscarThe popular name for the Academy Awards, referring to the gold-plated statuette of a medieval knight given to winners. for Best Picture. A joyful Cate Blanchett made a dazzling speech to a cheering audience while accepting her own award for Best Actress.

Of course, this is not what happened. It was Everything Everywhere All at Once that swept the Oscars, with its lead, Michelle Yeoh, also becoming the first Asian woman to win Best Actress.

But according to the film's central theme, there is a universe where Tar won. And a universe where the award went to Cocaine Bear. And a universe where the award for Best Actress was accepted by a pair of googly eyes stuck to a rock.

The film is based on multiverse theory, the idea that there are multiple realities where different versions of our lives are played out.

This is one of the many mind-boggling ideas that have come out of quantum mechanicsA fundamental theory in physics describing the properties of nature on an atomic scale. Unlike general relativity, which works when applied to large objects, quantum mechanics helps describe the world on a tiny level - at a scale where things can be in several places at once, and measurement can affect reality., one of the newest branches of physics.

The Copenhagen interpretation of quantum physics states that particles can exist in multiple different states in the same place.¹ This is called a superposition.

The multiverse is a way of making sense of this. If many versions of the same particle can exist at the same time, then it stands to reason that many versions of the same reality can also exist simultaneously.

Mathematicians also have their own version of multiverse theory. They say if the universe is infiniteLimitless or endless. An amount impossible to count. , then it must contain everything that can possibly exist. That means it must have infinite versions of Earth where everything that ever could have happened, has happened.

Some experts think that whether or not the multiverse is real, it plays an important psychological role in the modern world. Many believe that every time we make a choice, a different universe branches off in which we made the opposite choice.

Five hundred years ago, most people's lives were mapped out for them. Their religion, their job and their partner were all chosen for them. 

Today, we have to make all our own choices. Every choice that we make prevents us from living a different life. This can make us very anxious.

So believing in the multiverse can be comforting. It means we are not closing off possible lives; we are just letting other versions of ourselves live them.

Yes: Strange as it may seem, the multiverse is the only way of making sense of scientific and mathematical facts that we know to be true. 

No: Many experts say the multiverse is an unscientific theory because it cannot be falsified - there is no way of proving that it is not true. The fact that it logically could or even should exist does not mean that it does.

Or... Saying the multiverse is "real" does not really mean anything: it is only a thought experiment that we use to make sense of the world, not a physical place. However, it might do an anxious world a lot of good to believe in it.