# Can gravitons travel in a vacuum?

## Main Question or Discussion Point

I'm a complete newbie at physics so bear with me..

The minute a spaceship is out of the earths atmosphere and into the vacuum, the gravitational pull lets go and the spaceship is free.
So what I'm asking is, how can the sun attract the earth into its pull?

Can gravitons travel in a vacuum? if not how does it work?

Related Classical Physics News on Phys.org
Actually in order to be "free" from gravitational attraction you have to put an infinite distance between two objects.

I cannot tell you about Gravitons but I can tell you that gravitational effects need no medium to be transmitted.

SGT
bola said:
I'm a complete newbie at physics so bear with me..

The minute a spaceship is out of the earths atmosphere and into the vacuum, the gravitational pull lets go and the spaceship is free.
No, the gravitational pull will decrease with distance squared, so it will become smaller when the ship moves away, but it will only be zero at an infinite distance.
So what I'm asking is, how can the sun attract the earth into its pull?
Read above. Even distant stars exert a gravitational pull on Earth, but it is too small to be measured.
Can gravitons travel in a vacuum? if not how does it work?
Yes.

HallsofIvy
Homework Helper
Gravitational pull never "lets go". It drops off very rapidly (as 1/r2) but there is always some force (and the sun is very massive!). A lot of people confuse "free fall" with gravity "stopping". You feel gravity when there is something (like the earth or a floor) preventing you from going down. In space, when you shut off the rocket engines, you are in "free fall" because you are now "falling freely" with nothing to stop you. You could get the same effect by stepping off a tall building (except it won't last as long!).

DB
bola said:
Can gravitons travel in a vacuum? if not how does it work?
gravitons are just hypothetical particles to link Quantum Mechanics, General Relativity and gravity. they carry the force of gravity in (dont hold me to this)
wave packets. in Newtonian physics as we are talking about in this thread, they really dont matter.

pervect
Staff Emeritus