# Is general relativity correct?

Table of Contents

- 1 Is general relativity correct?
- 2 Is time different in space?
- 3 Why is it called space time?
- 4 What is the general theory of relativity in simple terms?
- 5 How did Einstein predict black holes?
- 6 Why is it called quantum theory?
- 7 What is E mc2 used for?
- 8 What happens to time at the speed of light?
- 9 Is gravity a law or a theory?
- 10 Who discovered special relativity?
- 11 What does Einstein’s equations of general relativity relate to?
- 12 What is meant by length contraction?
- 13 How many dimensions are there in string theory?
- 14 What is string theory in layman’s terms?
- 15 What do you mean by inertial frame of reference?

## Is general relativity correct?

The predictions of general relativity in relation to classical physics have been confirmed in all observations and experiments to date. Although general relativity is not the only relativistic theory of gravity, it is the simplest theory that is consistent with experimental data.

## Is time different in space?

So depending on our position and speed, time can appear to move faster or slower to us relative to others in a different part of space-time. And for astronauts on the International Space Station, that means they get to age just a tiny bit slower than people on Earth. That's because of time-dilation effects.

## Why is it called space time?

Space-time is a mathematical model that joins space and time into a single idea called a continuum. This four-dimensional continuum is known as Minkowski space. … This is because the observed rate at which time passes depends on an object's velocity relative to the observer.

## What is the general theory of relativity in simple terms?

General relativity is a theory of space and time. The theory was published by Albert Einstein in 1915. The central idea of general relativity is that space and time are two aspects of spacetime. Spacetime is curved when there is gravity, matter, energy, and momentum.

## How did Einstein predict black holes?

In 1915, Albert Einstein developed his theory of general relativity, having earlier shown that gravity does influence light's motion. Only a few months later, Karl Schwarzschild found a solution to the Einstein field equations, which describes the gravitational field of a point mass and a spherical mass.

## Why is it called quantum theory?

The word quantum derives from the Latin, meaning "how great" or "how much". … The discovery that particles are discrete packets of energy with wave-like properties led to the branch of physics dealing with atomic and subatomic systems which is today called quantum mechanics.

## What is E mc2 used for?

The mass–energy equivalence formula was used in the understanding of nuclear fission reactions, and implies the great amount of energy that can be released by a nuclear fission chain reaction, used in both nuclear weapons and nuclear power.

## What happens to time at the speed of light?

The faster the relative velocity, the greater the time dilation between one another, with the rate of time reaching zero as one approaches the speed of light (299,792,458 m/s). … For sufficiently high speeds, the effect is dramatic. For example, one year of travel might correspond to ten years on Earth.

## Is gravity a law or a theory?

Gravity is most accurately described by the general theory of relativity (proposed by Albert Einstein in 1915) which describes gravity not as a force, but as a consequence of the curvature of spacetime caused by the uneven distribution of mass.

## Who discovered special relativity?

The history of special relativity consists of many theoretical results and empirical findings obtained by Albert A. Michelson, Hendrik Lorentz, Henri Poincaré and others. It culminated in the theory of special relativity proposed by Albert Einstein and subsequent work of Max Planck, Hermann Minkowski and others.

## What does Einstein’s equations of general relativity relate to?

Einstein thought of the cosmological constant as an independent parameter, but its term in the field equation can also be moved algebraically to the other side, written as part of the stress–energy tensor: … Thus, the terms "cosmological constant" and "vacuum energy" are now used interchangeably in general relativity.

## What is meant by length contraction?

Length contraction is the phenomenon that a moving object's length is measured to be shorter than its proper length, which is the length as measured in the object's own rest frame. … Length contraction is only in the direction in which the body is travelling.

## How many dimensions are there in string theory?

One notable feature of string theories is that these theories require extra dimensions of spacetime for their mathematical consistency. In bosonic string theory, spacetime is 26-dimensional, while in superstring theory it is 10-dimensional, and in M-theory it is 11-dimensional.

## What is string theory in layman’s terms?

String theory is a set of attempts to model the four known fundamental interactions—gravitation, electromagnetism, strong nuclear force, weak nuclear force—together in one theory. … Einstein had sought a unified field theory, a single model to explain the fundamental interactions or mechanics of the universe.

## What do you mean by inertial frame of reference?

An inertial frame of reference in classical physics and special relativity possesses the property that in this frame of reference a body with zero net force acting upon it does not accelerate; that is, such a body is at rest or moving at a constant speed in a straight line.