Hypothetical question time

[TheCanadianVendingMachine]

What would happen if you are outside of the Milky Way, outside of any gravity field that can make big affects. Then slow the ship down to 0m/s. What would happen?

[brooklyn666]

There is no "outside of any gravity field." galaxies are gravitationally bound in groups, groups are bound in clusters, clusters in superclusters...

[dharak1]

As far as I know fall towards the strongest gravitational field.

[K^2]

Then slow the ship down to 0m/s. What would happen?

Relative to what?

But if you are far enough from gravity sources for gravity to be negligible, then your acceleration will also be negligible, and you'll stay very close to whatever velocity you've been at.

[DaveofDefeat]

I'd say you would drift in space for a rather large amount of time.

[Camacha]

Relative to what?

I wanted to say this. Speed is always measured in relation to something else, so what is you baseline? As different galaxies are moving apart and some together, you will always be moving in relation to most of them.

[WestAir]

If every particle in the universe immediately froze relative to all other particles in the universe, then was allowed to proceed from a 0 m/s relative to all other particles, would we encounter a "BIG CRUNCH" end to the cosmos?

[TheCanadianVendingMachine]

Sorry, I meant it in a way as you did it. But you are inside, would you float or...?

[Camacha]

But you are inside, would you float or...?

I think you would feel pretty and behave much exactly like when in orbit. There are no major forces acting upon you, so you are not going anywhere without interacting with something.

[The Destroyer]

I think you would feel pretty and behave much exactly like when in orbit. There are no major forces acting upon you, so you are not going anywhere without interacting with something.

Exactly what I was thinking.

[K^2]

If every particle in the universe immediately froze relative to all other particles in the universe, then was allowed to proceed from a 0 m/s relative to all other particles, would we encounter a "BIG CRUNCH" end to the cosmos?

No. Expansion is accelerating. If you somehow managed to stop it, and then let go, it'd still expand. Why gravity suddenly turns repulsive on grand scale is the million dollar question in cosmology right now. GR predicts that to this repulsion corresponds a so-called dark energy, and there is bloody lot of it in the universe, except, for some reason, nowhere where we can see it. So yeah, a riddle wrapped in a mystery inside an enigma.

[Spartan125]

What would happen if gravity didn't exist all of a sudden?

[ZetaX]

You will die.

[Skyler4856]

You would slowly begin accelerating towards the nearest massive object. As to slowing the ship down to 0 m/s, that defies relativity. O m/s in reference to what? My origin point? The nearest object? Regardless of your reference point you would still be accelerating with the expansion of space.

Ugh ninja'd

[Beowolf]

If every particle in the universe immediately froze relative to all other particles in the universe, then was allowed to proceed from a 0 m/s relative to all other particles, would we encounter a "BIG CRUNCH" end to the cosmos?

That one comes down to details humanity doesn't know yet. Are dark energy and gravity propagated by particles? If not, others' answers about expansion continuing are correct. But if they are particles and you're stopping literally ALL particles...I think you've essentially stopped time.

I was more intrigued thinking about what happens to the particles that CAN'T stop, like photons. Since photons do exert pressure on matter, if you didn't stop them too they'd ruin your experiment. But I've never even heard of a hypothetical way to stop a photon...or affect its speed in any way, really. You can slow a photon's forward progress by making it pass through dense materials, but that's just because it's ricocheting around inside. The photon never actually slows down.

300 million meters/second. It's the law.

[Kulebron]

What would happen if gravity didn't exist all of a sudden?

You'd fly in space because of Earth centrifugal force, and Earth would explode because of internal pressure not being counteracted by gravty anymore.

[insylem]

You can measure speed reletive to the "fabric" of spacetime itself..

Simply look for the doppler shift in the 3 kelvin background radiation.

And at that, the awnser would be.

You'd just sit there... not moving.. accelerating VERY VERY slowly, becuase there would be SOME gravity from somewhere, but not a noticeable amount.