The universe is a vast and complex entity that has been the subject of human curiosity for centuries. Despite our many advancements in science and technology, we still have much to learn about the universe and what it’s made of. In this article, we’ll explore the mysterious composition of the universe and what scientists have discovered so far.
Dark Matter
One of the most intriguing mysteries of the universe is the presence of dark matter. Dark matter is a type of matter that cannot be seen with telescopes or detected with any of our current technology. Scientists believe that dark matter makes up about 27% of the universe, based on its gravitational effects on visible matter. However, the exact nature of dark matter remains unknown, and it continues to be one of the most fascinating and enigmatic mysteries of the universe. The following are six theories of what dark matter could be.
WIMPs: Weakly Interacting Massive Particles (WIMPs) are the leading candidates for dark matter. WIMPs are particles that interact only through the weak nuclear force and gravity, making them difficult to detect. They are thought to have a mass of about 100 times that of a proton and may be produced in the early universe.
Axions: Axions are hypothetical particles that were proposed to explain why the strong nuclear force doesn’t violate CP symmetry. They were later proposed as a possible candidate for dark matter. Axions are thought to have a very small mass and interact very weakly with matter, making them difficult to detect.
MACHOs: Massive Compact Halo Objects (MACHOs) are objects such as brown dwarfs, black holes, or planets that are too small to be stars but too large to be planets. They could be dark matter if there are enough of them, but current observations suggest that they cannot account for all of the dark matter.
Sterile Neutrinos: Neutrinos are elementary particles that have a very small mass and interact only through the weak nuclear force. Sterile neutrinos are hypothetical particles that do not interact through any known forces except gravity. They could be a candidate for dark matter if they have a mass of a few keV.
Modified Gravity: Some scientists have proposed that the laws of gravity need to be modified to explain the observed gravitational effects of dark matter. This theory, called Modified Newtonian Dynamics (MOND), suggests that gravity behaves differently at large scales than it does at small scales.
Dark Photons: Dark photons are hypothetical particles that are thought to interact with dark matter through a force similar to the electromagnetic force. They could be a candidate for dark matter if they have a mass in the range of a few electronvolts.
While scientists have proposed various theories about what dark matter could be, its true nature remains a mystery. Future research and observations may help to shed light on this enigmatic substance and unravel the secrets of the universe
Dark Energy
Dark energy is a mysterious component of the universe that makes up about 68% of the universe. It is believed to be responsible for the accelerated expansion of the universe. Scientists have discovered the existence of dark energy through its effects on visible matter, but they still do not know what dark energy actually is or how it behaves. Dark energy is what most people think of when they hear the word “dark”. It’s a term used to describe an unknown and mysterious force within the universe. Dark energy seems to defy gravity, pushing the universe apart faster and faster. This is why it is also called “repulsive dark energy.” In recent years, scientists have come up with two possible theories as to how dark energy behaves. The first theory says that it exists as one form called quintessence, while the second theory says that it comes in many different forms. Multiple universes are possible.
Visible Matter
Visible matter, commonly referred to as baryonic matter, only accounts for 5% of the universe. It’s everything we can see and interact with - stars, planets, galaxies and more. This type of matter is made up of atoms which further comprise of protons, neutrons and electrons. It also seems to be the most abundant and fundamental form of matter.
Cosmic Background Radiation
Cosmic background radiation is the faint glow of light that fills the universe and serves as a reminder of the Big Bang. This radiation was discovered in the mid-1960s and is believed to be the afterglow of the Big Bang, the explosive event that created the universe. Cosmic background radiation provides valuable information about the early universe and helps scientists understand the origin and evolution of the universe. It is a remnant from the Big Bang and is composed of photons, or particles of light. The signal is strongest in the microwave region of the spectrum and can be detected with radar-based instruments. The strength of this radiation decreases as one moves further away from Earth, but it never completely disappears. This means that there are no large structures or sources that could absorb it to measure its original intensity, making cosmic background radiation a valuable tool for observational cosmology: providing information about where space-time begins and ends as well as detecting vast cosmic structures like galaxies.
Conclusion
The universe is a complex and mysterious entity that scientists are still trying to understand. While we have made many advancements in our understanding of the universe, much remains unknown. Dark matter, dark energy, visible matter, and cosmic background radiation are just a few of the many components of the universe that continue to captivate the minds of scientists and the public alike. The study of the universe is a never-ending journey of discovery, and we look forward to learning more about the cosmos in the years to come.