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Researchers have been looking at everything, including supernovas, trying to uncover the mysteries of dark matter. Recent scientific studies suggest that dark matter might not be a particle hiding in the universe. Instead, it's possible that it could be the result of physics happening in a hidden, fifth dimension. According to a 2024 article in Wired, researchers working in string theory proposed a "dark dimension scenario." In addition to the four already-known dimensions of spacetime, consisting of the three spatial dimensions plus time itself, there could be a compact fifth dimension that potentially explains the effects credited to dark matter, including why gravity is weaker than other forces.
In the extra dimension, there could be heavy particles called gravitons or other particles that carry gravity that act like dark matter. This would add the "missing mass," helping to explain why galaxies spin like they do and how the universe's structure forms. SciTechDaily explains that some scientists think looking at ordinary particles from a five-dimensional perspective could produce a new heavy particle that connects normal matter with hidden "dark" matter. These ideas suggest that the universe's missing mass may not be missing after all; it could just be hidden in a fifth dimension beyond our space and time.
Dark matter explained
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Dark matter is invisible "stuff" in the universe that we can't see or touch, but we know it's there because of how it pulls on stars and galaxies with gravity. For instance, think of the stars in a galaxy as racecars driving around a NASCAR track. They are moving so fast that without some kind of invisible weight to hold them together, they would fly off the track. That invisible weight is dark matter. For analogy's sake, let's talk Avengers movies. The Tesseract was a magical cube that acted as a bridge, letting heroes and villains travel instantly between realms and worlds. Loki used it to travel to Earth in the opening scene of the first movie, while Thanos went just about anywhere he wanted in "Avengers: Infinity War."
Scientists have presented a similar idea, the "dark dimension scenario," to try and explain the nature of dark matter. The hidden fifth dimension is like the "other side" of a Tesseract portal, the part of the universe we can't see in our normal 3D space; however, dark matter might live there, which is why we can see its effects even though we can't see it directly. But even though it's still not fully understood, scientists have the belief that dark matter can be heated and even moved.
Why is science obsessed with Dark Matter?
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There could be some pretty big implications if the dark dimension scenario is correct, completely changing the way scientists think about the universe. If dark matter exists in a hidden fifth dimension, scientists now have a pathway on where to look. The proposed scenario predicts new heavy particles that could be like messengers between our familiar universe and the hidden space beyond, and discovering these particles would give researchers the first direct evidence of physics beyond our four-dimensional world. Experiments are being created and tools like the new observatory are being used to redefine what researchers already know and to search for unusual signals, like subtle gravitational effects or traces of particles that appear and disappear in ways normal matter doesn't.
For example, studies have proven that dark matter's gravity bends light substantially, resulting in an effect called gravitational lensing, leaving essential clues scientists need to confirm if the fifth dimension does in fact exist. If scientists can find a fifth dimension, it would explain dark matter and would expand the laws of physics as we know them, influencing how scientists understand gravity, the formation of galaxies, and even the future of particle physics experiments, expanding the exploration limits of science.
