“Nature doesn’t treat both directions of time equally.”
We all experience time — it continuously moves forward whether we like it or not. There have been several theories regarding why this is the case, but it is pretty much accepted by most of the scientific community that it is an inevitable and fundamental fact of nature.
However, new research from Joan Vaccaro of Griffith University’s Centre for Quantum Dynamics in Australia is challenging this long-held presumption of time. In the paper, titled “Quantum asymmetry between time and space,” Vaccaro suggests there may be a deeper origin due to a difference between the two arrows of time — forwards and backwards — which is constantly pushing us to the future instead of the past.
This means that the two directions of time may not be identical after all. “In particular, subatomic particles called K and B mesons behave slightly differently depending on the direction of time. In other words, the subtle behaviour appears to be responsible for making the universe move forwards in time,” said Vaccaro in a press release.
“While we are indeed moving forward in time, there is also always some movement backwards, a kind of jiggling effect, and it is this movement I want to measure using these K and B mesons,” added Vaccaro.
What makes time so perplexing is that even though it is moving forward, if we look very closely at individual atoms and molecules, it really doesn’t matter whether time is moving forwards or backwards — they behave the same way.
However, that is not the case with space, so scientists assumed that there must be some fundamental reason why the universe continues to move forward in time, but not in space. This is known as the asymmetry between time and space.
“In the connection between time and space, space is easier to understand because it's simply there. But time is forever forcing us towards the future,” said Vaccaro.
“If you want to know where the universe came from and where it's going, you need to know about time,” Vaccaro added. “Experiments on subatomic particles over the past 50 years ago show that Nature doesn't treat both directions of time equally.”
According to ScienceAlert, to investigate her theory, Vaccaro reworked the equations of quantum mechanics while assuming that time was not identical in both directions. Her results showed that these calculations accurately described the universe.
“When this subtle behaviour is included in a model of the Universe, what we see is the Universe changing from being fixed at one moment in time to continuously evolving,” said Vaccaro. “In other words, the subtle behaviour appears to be responsible for making the Universe move forwards in time.”
Confirming this theory could lead to some monumental changes in how we currently understand and think about time. “Understanding how time evolution comes about in this way opens up a whole new view on the fundamental nature of time itself,” Vaccaro explained. “It may even help us to better understand bizarre ideas such as travelling back in time.”