In four ways, quantum mechanics will call the existence into question.
Consider opening the weekend newspaper and searching the puzzle pages for the Sudoku puzzle. You spend the morning working on this logic puzzle, only to find that there is no consistent way to finish it by the last few squares.
You say to yourself, “I must have made a mistake.” But you try again, this time starting from the corner where you failed and working your way around. However, the same thing occurs once more. You’ve come down to the final few squares and can’t seem to find a consistent solution.
Finding out the underlying essence of life using quantum mechanics is a bit like solving an impossible Sudoku puzzle. We still end up at a conundrum with quantum theory, no matter where we start. It causes us to reconsider how the world fundamentally works. (This is why quantum mechanics is so fascinating.)
Let me take you on a brief tour, through the eyes of a philosopher, of the world according to quantum mechanics.
1.Suspenseful action from-a-far
The speed of light (around 300 million metres per second) is the universe’s absolute speed limit, as far as we know. Albert Einstein famously laughed at the possibility of physical structures affecting one another faster than light could pass between them.
This was dubbed “spooky action-at-a-distance” by Einstein in the 1940s. When quantum mechanics seemed to predict certain strange events in the past, he argued that the theory had not yet been completed, and that a better theory would reveal the reality.
Today, we know that such a better theory is extremely unlikely. And if we believe the universe is made up of well-defined, self-contained “stuff,” then our world must allow for spooky action-at-a-distance between these pieces of “stuff.”
2.Weakening our hold on reality
“What if the world is not made of well-defined, independent pieces of ‘stuff’?” I hear you say. “Then can we avoid this spooky action?”
Yes, we definitely can. Many people in the quantum physics community believe the same thing. This, however, would be of little comfort to Einstein.
This was the topic of a long-running debate between Einstein and his friend, Danish physicist Niels Bohr. Bohr concluded that we should abandon the notion that the material of the universe is well defined in order to prevent spooky action-at-a-distance. According to Bohr, the universe has no definite properties until we look at it. When we are not looking, the universe as we know it does not exist, according to Bohr.
But, regardless of how we look at it, Einstein maintained that the universe is made of something; otherwise, we wouldn’t be able to speak to each other about it, and science would cease to exist. But Einstein couldn’t have a well-defined, autonomous universe and no creepy action-at-a-distance at the same time… or would he be able to?
3.Returning to the future
In the history of quantum mechanics, the Bohr-Einstein controversy is fairly well-known. The hazy corner of this quantum logic puzzle, where we can save both a well-defined, independent universe and no spooky behaviour, is less well-known. However, we’ll have to get weird in other ways as well.
If measuring a quantum system in the lab has the potential to change how the system was before the measurement, Einstein might have his cake and eat it too. Since the results of conducting the experiment will have to move “backwards in time,” this theory is known as “retrocausality.”
You are not alone in thinking this is weird. This is not a commonly held belief in quantum mechanics, but it does have supporters. When faced with the prospect of spooky action-at-a-distance or no world-as-we-know-it if we don’t look, retrocausality might not seem so strange after all.
4.There is no view from Olympus.
Imagine Zeus standing atop Mount Olympus, looking out over the universe. Imagine being able to see all that has happened and will happen in the future, from any location and at any time. This is known as the “God’s eye view” of the universe. It’s normal to believe that the universe must be in some way, even though it can only be understood by an all-seeing God.
Recent quantum mechanics research shows that a God’s eye view of the universe is theoretically unlikely. Different scientists will look closely at the processes in their laboratories and make comprehensive recordings of what they see – but when it comes time to compare notes, they can disagree on what happened. And there may be no real truth to the matter of who is right – not even Zeus knows!
So the next time you come across an impossible Sudoku, know that you’re not alone. The entire quantum physics world, and possibly even Zeus himself, is aware of your feelings.