# What happens if the range of gravity extends only 10 light minutes?

If the range of gravity abruptly shortens from infinite to mere 10 light minutes, assume no other changes in properties and this effect occurs at no time at all. What happens beyond the Sun's gravitational drop-off?

• Can you elaborate further? For example, how does gravity work at lim_[x->10-] x light-minutes? – SOFe Sep 10 '16 at 7:12
• So at lim_[x->10+] x light-minutes, you receive no external gravitational forces at all, and at lim_[x->10-] x you suddenly get a relatively infinitely greater force? That feels wrong... I mean, in real life, we never encounter any sudden increase in force, only a gradual, even if an enormous slope, increase... – SOFe Sep 10 '16 at 7:22
• @PEMapModder: tell that to the nuclear physicist ask them how the weak and strong force works😁 – user6760 Sep 10 '16 at 7:27
• @Mołot But the strong nuclear force does. A conceptual answer is possible, this is only hypothetical after all. See the answers below. – a4android Sep 10 '16 at 10:45
• @Mołot. Very interesting, but at distances in units of 10^-15 m, that's close enough to ending abruptly even it falls smoothly and fast. This could easily describe this hypothetically short-range gravity's limit. Any idea that it would fall to zero in zero distance is amusing to say the least. – a4android Sep 10 '16 at 11:23

## Solar systems don't even form.

Ten light-minutes is barely more than the radius of Earth's orbit around the sun. Assuming gravitational effects have always been short-to-medium-range phenomena no celestial body large enough to initiate stellar fusion would ever form. The accumulation of matter in gravity wells from the supposed "initial condition" of a baryonic soup depends on the attraction of gravity accumulating over much larger distances than this.

# 1- The Universe Would Be Cold ... And Dead

Considering that solar systems have planets at distances of several dozen light minutes (Earth is at 8:20 while Jupiter is at more than 40 light minutes from the sun), the solar systems, as know them, would never form. You might think that Earth-like terrestrial planets would still form around stars, but that would be impossible. Read ahead.

Galaxies have lengths of dozens of thousands of light years. Limiting gravity to mere minutes range would mean that galaxies never form at all. Without going into lengthy details, let it suffice to say that supermassive blackholes of galactic centers never form at all, putting galaxies out of the picture completely.

Which means that after the Big Bang, universe would go on to expand at nearly the speed of light. Once the individual particles are more than 10 light minutes away from one another, there would be no way for them to ever reunite.

The universe would just be composed of infinitely small, infinite number of sub-atomic particles, moving away from one another at 99.999% the speed of light. It would be a dark, cold, dead universe.

# 2- If It Was Thus, You Would Never Get To Ask This Question

This should be self-evident.

• #2 says it all that's why there is no #3 – NuWin Sep 10 '16 at 22:48