Frequently used to change scenery in science fiction, parallel universes and the multiverse are indeed possible, but jumping from one to another might be a little tricky.
How can you see something that’s invisible? Well, with Euclid! This future ESA telescope will map the structure of the universe and teach us more about invisible dark matter and dark energy. Scientific coordinator of Euclid and Leiden astronomer Henk Hoekstra explains how this works.
Why do we assume that dark matter exists, if we have never seen it or even measured it? “We are orbiting the centre of our galaxy at 220 kilometres per second,” says Hoeksta. A bizarre speed, which fortunately we don’t notice. Still, something strange is going on. “Based on the number of stars in our Milky Way, the stars at the edge of the Milky Way should have a much lower speed, but they move as fast as the Sun. Yet these stars are not being slung into the universe. Something is holding them together.”
Is our Universe really the only one? A new theory that hopes to solve one of the biggest problems in physics, may have rewritten our perception of time, and found a way through the Big Bang. Video by Howard Timberlake.
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Physicists have long searched for hypothesized dark matter particles called WIMPs. Now, focus may be shifting to the axion — an ultra-lightweight particle whose existence would solve two mysteries at once.
Cosmology draws on many branches of physics to study the universe’s history. And what it’s found has forever changed how we understand our position in the cosmos.