What is the difference between dark matter and dark energy?

Our universe is dominated by mysterious and invisible forms of matter and energy that are not yet fully (or fully) understood. Two galaxy clusters collided to form the “bullet galaxy cluster” shown here. Regular matter is shown in pink and the rest in blue, indicating that dark matter dominates this huge cluster.

Most of our universe is hidden. Although we can’t see or touch it, most astronomers say that most of the universe is made up of dark matter and dark energy. But what is this mysterious and invisible thing around us? And what is the difference between dark energy and dark matter? Dark matter slows down the expansion of the universe, while dark energy accelerates it. Dark matter acts like gravity, the cosmic glue that holds our universe together. This is because dark matter interacts with gravity but does not reflect, absorb, or emit light. Dark energy, on the other hand, is a type of anti-gravity that is causing the accelerated expansion of the universe. Of the two energies, dark energy is by far the more dominant, accounting for about 68 percent of the universe’s total mass and energy. Dark matter accounts for 27 percent. And the rest – just 5% – are ordinary things we see and interact with every day. dark matter In the 1930s, Swiss-born astronomer Fritz Zwicky examined images of the approximately 1,000 galaxies that make up the Coma Cluster and noticed something strange about their behavior. The galaxy was moving so fast that it simply had to fly away. He suspected that some kind of “dark matter” was holding them together. Decades later, astronomers Vera Rubin and Kent Ford discovered a similar phenomenon while studying the rotational speed of individual galaxies. Stars on the outer edge of a galaxy should orbit more slowly than stars near the center. This is how planets orbit within our solar system. Instead, they found that stars at the edges of galaxies orbit as fast as, or even faster than, the stars around them. Rubin and Ford found further evidence that invisible matter apparently holds the universe together. “Even stars in peripheral orbits are orbiting at high speeds,” Rubin once explained in an interview with Discover. “For stars to orbit this fast, they must have a lot of mass, but we can’t see it. This invisible mass is called dark matter.”

How was dark matter discovered? What is dark matter made of? How is dark matter different from dark energy? Astronomy’s free downloadable e-book “The Science Behind Dark Matter” contains everything you need to know about the elusive and invisible substance. Astronomers now have more evidence suggesting the existence of dark matter. In fact, the existence of dark matter is widely accepted and is part of the so-called standard model of cosmology, which forms the basis of how scientists understand the formation and evolution of the universe. Without them, we cannot explain how we got here. But this high status puts pressure on cosmologists to find conclusive evidence that dark matter exists and that their models of the universe are correct. For decades, physicists around the world have been using increasingly sophisticated equipment to detect dark matter. So far, no signs of this have been found. dark energy Astronomers have known for about a century that the universe is expanding. Telescopic observations show that most galaxies are moving away from each other, suggesting that they were once closer together in the distant past. As a result, evidence of the Big Bang accumulated. However, astronomers believed that the sum of the gravitational forces of all the stars and galaxies in the universe should slow the expansion of the universe. Perhaps someday there will be a major crisis and it will collapse again. However, this idea was rejected in the late 1990s when two teams of astronomers discovered something that didn’t make sense. Researchers studying supernovae in the most distant galaxies have discovered that distant galaxies are moving away from us faster than nearby galaxies. The universe was not just expanding, but the expansion was accelerating. “My own reaction is somewhere between surprise and horror,” astronomer Brian Schmidt, who led one of the two teams, told the New York Times in 1998. “I was surprised because this result was completely unexpected, and horrified that the majority of astronomers, who, like me, are highly skeptical of unexpected events, are unlikely to believe it. “I’m here” However, subsequent observations did not disprove it, but only made the evidence for dark energy even stronger. In fact, some prominent dark matter critics still acknowledge the existence of dark energy. But that doesn’t mean researchers know what dark energy is. Far from it. But thanks to Albert Einstein’s theory of general relativity, we can explain its role in the universe. Einstein knew nothing about dark energy, but his equations suggested that new space could be created. And he also introduced a false element into the theory of relativity called the cosmological constant. This is something he later regrets adding to prevent the universe from collapsing into itself. This idea creates energy in the space itself. However, scientists have never seen this force on Earth. Some theoretical physicists believe that a dark realm of particles and forces exists, waiting to be discovered. Whatever dark energy and dark matter are made of, they seem to be in a tug of war with our universe – holding it together and tearing it apart at the same time.