Astronomers regularly explore the universe using different wavelengths of the electromagnetic spectrum. However, there are problems with studying the universe this way. We can only see the light from when the universe was only 380,000 years old. Another approach is to use gravitational waves. Gravitational waves are thought to exist in the early universe, potentially allowing us to probe even deeper into the past. The concept of gravitational waves is actually quite simple. Imagine the structure of the universe in the form of a vast ocean. When an object moves within it, waves are generated and propagate through the water. Sea fog will limit visibility, but waves may still develop. Gravitational waves are like ripples in space caused by the motion of objects.
Rishabh Roshan and Graham White from the University of Southampton believe gravitational waves can be used to explore the universe’s earliest moments. In the early stages of the creation of the universe, space was opaque because it was filled with ionized gas and electromagnetic radiation could not penetrate inside. Roshan and White believe they can overcome this barrier. In a paper published on the preprint server arXiv, they describe his three main strategies for detecting gravitational waves: pulsar time grids, astrometry, and interferometry. These methods are similar and all rely on gravitational waves that destroy the space between the elements of the system. In interferometry, gravitational waves are revealed by the destruction of the space between the optical elements of the system. In pulsar arrays, changes in the timing of pulses from a known pulsar system indicate the presence of waves, and using astronomical techniques, even small changes in the angular velocity of a target can reveal the presence of gravitational waves. Since their discovery, gravitational waves have provided valuable information about events in distant parts of the universe. Now it appears they can be used to solve the mysteries of not only space but also time.