The universe is believed to have been continuously expanding since the Big Bang. This expansion rate was reported to be relatively consistent for the first eight years due to the force of gravity. However, some missions revealed that expansion has accelerated over the past five billion years. Many attributed this acceleration to either a mysterious force called dark energy or a change in gravity. But, a new study shows, the nature of gravity has remained constant for the entire history of the universe. According to Einstein’s general theory of relativity, gravity changes the curvature of space-time. This theory has proven to be accurate in predicting the existence of black holes in the universe and many phenomena, including gravitational lensing.
Despite this, scientists were skeptical of this theory when they noticed some discrepancies. One of them was that the gravitational effects of giant cosmic structures did not correspond to their observed mass. This skepticism led to the theory that space is full of invisible mass. Meanwhile, the expansion of the universe gave rise to the theory of dark energy and the Lambda Cold Dark Matter (Lambda CDM) cosmological model.
To clear things up, researchers from the Dark Energy Survey (DES) collaboration Victor M. Blanco 4-meter telescope and observed galaxies 5 billion light-years away. With this, they aimed to determine whether gravity has changed over the past 5 billion years.
The team observed the images and found subtle distortions caused by dark matter in them. This distortion of space-time by the gravitational lens helps scientists know the force of gravity. The DES team also used this method and measured the sizes of more than 100 million galaxies, with all their observations matching the predictions of general relativity theory.
the conclusions were published In a paper in the American Physical Society Journal physical review d,
