Six Weighty Facts About Gravity
The force of gravity is something we rarely give much thought to unless we experience its effects, such as when we fall on ice or while climbing stairs.
Initially, scientists didn’t even consider gravity to be a force; rather, it was seen as the inherent inclination of everything on Earth to fall to the centre of the planet, whereas the other worlds followed different rules.
We now know that gravity has many more effects besides only causing objects to fall to the ground. The structure of the cosmos is determined by it, and it regulates the orbits of the planets around the sun. Like electromagnetism, weak force, and strong force, we acknowledge gravity as one of nature’s four basic forces.
Einstein’s general theory of relativity, which underpins the present understanding of gravity, is often regarded as one of the most successful theories in existence. Yet there are many things about gravity, such as how it interacts with the other fundamental forces, that we still don’t fully understand. And these are the strangest gravity facts we know.
By far, the weakest force we are familiar with is gravity
There is no opposite of gravity that may cause objects to move away from one another. Even while gravity may keep galaxies together, it is so feeble that stars consistently triumph over it. If you decide to defy Earth’s gravity and pick up an apple, you’ll be doing just that.
One quintillion times greater than the gravitational pull between an electron and a proton within an atom is the electric force between them. Indeed, we don’t know the precise strength of gravity since it is so faint.
The concept of weight is not the same as gravity
When asked why astronauts aboard the space station appear to float, it is commonly said that they are in zero gravity. Nevertheless, that’s not the case. For an astronaut, gravity is around 90% of what it is on Earth. Weight is the force the earth imposes back on a person on Earth, but astronauts experience no such force throughout their time in space.
Gravitational waves move at light speed
The existence of gravitational waves is predicted by general relativity. When gravitational waves drain energy from binary star systems, white dwarfs, and black holes in mutual orbit gradually draw closer to one other. Gravitational waves are produced by Earth’s orbit around the sun, however the amount of energy lost is negligible.
Scientists have been baffled by the microscopic behaviour of gravity
On the lowest of sizes, quantum theories, and in particular the Standard Model, describe the other three basic forces of existence. Although scientists are making progress, a quantum theory of gravity has yet to be developed.
The field of loop quantum gravity explores the use of quantum mechanical tools to the problem of describing the fabric of space and time. In the same manner as matter is composed of atoms, quarks, and gluons, this theory suggests that space-time itself is particle-like at the smallest scales. With this kind of structure, matter would be confined to moving in a hopping motion from one place to another on the mesh. Loop quantum gravity is therefore able to represent the gravitational action on a scale far smaller than the atomic nucleus.