An important part of long-term thinking is the never-ending search for very long-lived methods of information storage. A perfect, eternal storage medium still eludes us; most of the ones we’ve invented and used over the course of civilization have had their limitations – even stone, nickel, and sapphire have a shelf life.
But new research by a team of physicists now suggests that searching for a storage medium that lives forever may be a waste of energy, because the laws of physics themselves limit the amount of time that any information can be kept.
In a paper recently published by the New Journal of Physics, the researchers review how spacetime dynamics might influence the storage of information by asking how much data we can reliably hold on to from the beginning to the end of time.
In order to answer that question, the team combined Einsteinian cosmology with quantum theories about the nature of matter and reality. They worked with a standard model of the universe, called the Friedman-Lemaître-Robertson-Walker metric: based on Einstein’s theory of general relativity, it describes a universe that is homogeneous and isotropic, and therefore expands (or contracts) uniformly in all directions.
Working with this metric, the researchers modeled what would happen to stored data over the course of universe expansion. When you encode information into some kind of matter and then track what happens to your storage medium throughout the life course of the universe, you’ll find that the quantum state of its matter (in other words, its properties: its position, momentum, and spin) will eventually and inevitably change. The research team was able to prove that this change in state creates ‘noise’ that dampens the stored information. One of the research physicists explains the process in this video abstract of the paper:
The faster the universe expands, the team argues, the more ‘noise’ interferes with stored data. Looking at the storage of both classical information (anything encoded in bits) and quantum information (anything encoded by the quantum state of a given particle), they conclude that not very much data will last from the beginning to the end of time.
In other words, it seems as though we may be doomed to an eventual quantum dark age. Unless, of course, we always take care to anticipate these state changes, and continuously forward migrate our data.