The Mystery of Dark Matter

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The universe we know today is simply the tip of the iceberg. Everything we see- stars, planets, galaxies- account for less than 5% of what is actually out there. The exponential rest is made of 95% dark energy (68%) and dark matter (27%)-the dark reality-hindering our view of it (Planck Collaboration, 2020). Conversely, dark matter does not emit, absorb, or reflect light unlike ordinary matter. Nevertheless, the gravitational force exerted by dark matter forms galaxies and curves spacetime itself. 

What Is Dark Matter, and How Do We Know It Exists?

So, how do we know if dark matter is even real? Imagine spinning a bucket of water, if you spin fast enough, the water clings to the sides. Similarly, galaxies spin so rapidly that based on the visible matter alone, they should be flinging stars into space, but they don’t. Something unseen is holding them together- something exerting gravitational force without being perceptible (Rubin & Ford, 1970). That, is dark matter. 

Physicists have theorised that dark matter could be made up of WIMPs (Weakly Interacting Massive Particles) or axions, subatomic particles that interact only through gravity and possibly the nuclear force (Bertone & Hooper, 2018). Despite decades of experiments- from underground detectors like XENONnt and LUX-ZEPLIN, to the Large Hadron Collider (LHC), we have not detected these particles yet. Inherently, some scientists are even questioning whether dark matter is a new form of matter or an indication that our understanding of gravity itself is incomplete. 

It's hidden, nay invisible, but what if one found the key to control it? Theories show that undiscerned interactions between dark matter particles might yield leverage for some exotic propulsion technologies whereby perhaps soon, spacecraft will manipulate gravity; an engine may, by means of dark matter, warp space-time and therefore make interstellar travel as easy as crossing a room.

While it is a very speculative notion, there may be a direct connection between dark matter and wormholes, specifically hypothetical tunnels that cut through spacetime and could offer a shortcut through light-years of distance between regions of the universe (Morris and Torne, 1988). If dark matter is indeed helping keep such structures stable, science-fiction notions may bleed into reality-warp drives or intergalactic highways. 

Despite decades of research aimed toward it, dark matter remains one of the most enigmatic puzzles of current modern physics. Every powerful new experiment, whether success or failure, spurs us on to draft a new agreement on how to understand the universe. Knowing its true nature one day may alter physics and all exploration for the years or centuries to come. 

Solving the question of dark matter might not just change how we look at our universe, but also how we travel through it. 

References

Bertone, G., & Hooper, D. (2018). History of dark matter. Reviews of Modern Physics, 90(4). https://doi.org/10.1103/revmodphys.90.045002

Morris, M. S., & Thorne, K. S. (1988). Wormholes in spacetime and their use for interstellar travel: A tool for teaching general relativity. American Journal of Physics, 56(5), 395–412. https://doi.org/10.1119/1.15620

Gilmore, R. C., Somerville, R. S., Primack, J. R., & Domínguez, A. (2012). Semi-analytic modelling of the extragalactic background light and consequences for extragalactic gamma-ray spectra. Monthly Notices of the Royal Astronomical Society, 422(4), 3189–3207. https://doi.org/10.1111/j.1365-2966.2012.20841.x

Rubin, V. C., & Ford, W. K. J. (1970). Rotation of the Andromeda Nebula from a Spectroscopic Survey of Emission Regions. The Astrophysical Journal, 159, 379. https://doi.org/10.1086/150317