# Can massless objects be affected by gravity?

## Can massless objects be affected by gravity?

Massless particles are known to experience the same gravitational acceleration as other particles (which provides empirical evidence for the equivalence principle) because they do have relativistic mass, which is what acts as the gravity charge.

## Are you massless in free fall?

When this definition is used, an object in free fall is indeed “weightless”. How do you define the weight of the Earth? If you decide that it’s the force exerted by the Earth’s gravity on the Earth itself, then the answer is that the Earth’s weight is always zero.

Can something without mass move?

The only known particles with zero mass are photons. Light can be used to move objects (Try searching for Solar Sail) even thought light carries no mass, because it can carry momentum which can be transfered to objects.

### How can light be affected by gravity if it has no mass?

It might be surprising to you to hear that gravity can affect light even though light has no mass. If gravity obeyed Newton’s law of universal gravitation, then gravity would indeed have no effect on light. The gravitational curvature of light’s path is a weak enough effect that we don’t notice it much on earth.

### Can massless particles travel faster than light?

Massless particles are not only unable to move faster than light; they’re unable to move slower than light, too. The massless particles must move exactly by the speed of light.

Is mass an invariant?

The word mass has two meanings in special relativity: invariant mass (also called rest mass) is an invariant quantity which is the same for all observers in all reference frames, while the relativistic mass is dependent on the velocity of the observer.

#### Does gluon have mass?

Photons, which carry the force between the electrons, are there- fore massless. In contrast to electromagnetism, the range of the strong force does not extend outside the nuclei of atoms. This fact would imply that gluons are very massive. Gluons, however, appear to be massless.

#### Is a photon massless?

Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely “no”: the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits.

How can black holes be massive but not big?

Small black holes, or stellar-mass black holes, are more massive than our sun, but not by that much. Through mergers with other black holes and by slowly feeding on any stray bits of gas that wander too close to their ever-hungry mouths, these black holes can get bigger.