With great power comes great responsibility. As our grip on Earth grows ever tighter, so does the possibility that we could destroy it, or at least ourselves. But the prospect pales into insignificance when you consider that we may have the power to do something even worse.
We could destroy the universe.
Advertisement
Remember the outcry when CERN was getting ready to start smashing particles together in its Large Hadron Collider? A few doomsayers warned that it might be opening the door to the apocalypse.
This existential angst was triggered by the prospect of protons colliding at extremely high energies. Einstein鈥檚 general theory of relativity suggests that concentrating this kind of energy in a volume smaller than an atom might distort space and time enough to tear a hole in the fabric of the universe. This 鈥渕ini black hole鈥� could rapidly expand to engulf the entire cosmos.
CERN took the possibility seriously enough to carry out the ultimate workplace health and safety assessment. In 2008, it declared the disaster scenario virtually impossible. That assessment still stands, even though the LHC is now powering up to almost double its original energy.
We aren鈥檛 completely off the hook, however. That鈥檚 because the Higgs boson, discovered in the LHC in 2012, has given us reason to believe we might destroy the universe in a completely different way.
This danger was first by physicists Lawrence Krauss and James Dent, both then at Case Western Reserve University in Cleveland, Ohio. The problem, they said, is that the universe is governed by the rules of quantum physics, where observations of a system can affect its state (see 鈥�Does consciousness create reality?鈥�).
The notion might be familiar to you in the form of Schr枚dinger鈥檚 cat. In this thought experiment, a cat is placed in a sealed box with a vial of deadly poison that will be cracked open if a quantum event occurs: the radioactive decay of an atom. According to standard interpretations of quantum theory, as long as the box remains sealed, the cat is both alive and dead. It is the act of opening the box and observing the state of the cat that determines whether the radioactive decay occurs. In other words, human observation changes the state of the system.
Krauss and Dent suggested that something similar applies to the universe. It is theoretically possible to write down a quantum state for the cosmos. This moves between different states, just like the radioactive atom in the Schr枚dinger鈥檚 cat experiment, and can be similarly affected 鈥� in theory 鈥� by human observations.
An observation of something that is a property of the whole cosmos, such as the dark energy thought to be accelerating the universe鈥檚 expansion, might cause a sudden shift from being in a mixture of two states to being in one definite state. So looking at a supernova could be enough to alter the overall quantum state of the universe. The result might just 鈥渞eset鈥� the universe鈥檚 state, moving it back to where it was a few moments before. But there is a remote possibility of catastrophe.
This is because we are living in what physicists call a false vacuum 鈥� essentially an unstable configuration of space and time. That means the universe鈥檚 quantum state is slowly decaying towards a more stable one. However, an observation could tip it into that state abruptly. The universe would suddenly cease to exist, then reappear as a new, more stable cosmos 鈥� without us in it.
Not surprisingly, this was a controversial idea when first raised, not least because we didn鈥檛 know whether we were living in a false vacuum. However, some of the properties of the Higgs boson tell us that we almost certainly are. 鈥淭he discovery makes the issues we discussed more relevant,鈥� says Krauss, who is now based at Arizona State University.
We don鈥檛 know for sure that observing the cosmos can affect its quantum state. If it does, we really could precipitate our universe鈥檚 demise. But like the LHC black hole scare, it isn鈥檛 something that should keep us awake at night; Krauss says it was just a thought experiment, not a proof of peril.
Read more: 鈥�The human universe: Exploring our place in space鈥�
This article appeared in print under the headline 鈥淐ould we destroy the universe?鈥�
