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As long as we are talking about how far you can go in one lifetime, how would human body react in a spaceship with that much mass? Wouldn't the gravity crush an

As long as we are talking about how far you can go in one lifetime, how would human body react in a spaceship with that much mass? Wouldn't the gravity crush any humans to death. 10% of the sun's mass is more than 30,000 times earth's mass. Add to that the fact that the diameter is only 620 m, and the gravity becomes 1.4e13 g.

sombremesa 5y ago
The solar system is traveling in space and is quite massive but I haven’t been crushed to death yet.
- smnrchrds 5y ago
  You are far away from the masses. We are alive because we only experience 1g on earth. 10g is enough to kill a human. I don't even know what 14,000,000,000,000g would do, but I imagine we would get added to the neutron star.
  - IIsi50MHz 5y ago
    1g towards Earth's center. Well, center of mass. :adjusts bow tie: Welllll…combination of that and angular momentum. Combined with the masses of the sun, and the moon, the other planets, and all the other masses of the universe. Fortunately, orbits factor in, too. Everything that orbits is essentially in free fall, wellll…until they get tooo eliptical and the oscillating accelerations get really noticeable. And it all affects time. Time is a bunch of wibbly-wobbly…stuff. (( Ok, ok: Matt Smith might not have been that wordy as The Doctor. ))
brendyn 5y ago
If we could somehow make it into a donut planet we could presumably sit in the middle of it experiencing no acceleration. Would the time dilation effects still occur then?
- unlaxedneurotic 5y ago
  I don't think so. As I understand it, gravity and acceleration are equivalent, if you aren't experiencing any acceleration then time dilation won't occur. (Assuming we are not traveling near the speed of light)
  - darken 5y ago
    One of the more mindbending things to wrap your head around is that gravity isn't a force (i.e doesn't not cause acceleration in the F=Ma sense.). You're simply on a path through spacetime warped by gravity. Think about it: when you are in free fall you feel 0 acceleration. You appear to be accelerating relative to the ground-- but you're actually motionless in an "inertial reference frame". (Similar to how the astronauts on the ISS don't "feel" acceleration despite accelerating rapidly relative to the earth.) The "force" of gravity is often modeled as "gravity pulling you down" and the ground "pushing you back up". This works mathematically, but isn't quite logically consistent. In reality, on the ground you're in a region of warped spacetime, so you feel constant upward acceleration despite not actually accelerating. (Thinking of this another way, standing on earth feels identical to being in a far away spaceship accelerating at 9.8 m/s².) This is also why time "speeds up" near more massive objects. (Separate from "acceleration".) We're so used to gravity this it doesn't seem weird. But when you consider the fact free-fall is when you're not accelerating... well pondering that from many angles is what ultimately led Einstein to his model of relativity. (This is me trying to condense what could be a 10 minute explanation into a few sentences, so apologies if it's not particularly clear.)
    - badocr 5y ago
      The Veritasium youtube channel has a great video about this: https://www.youtube.com/watch?v=XRr1kaXKBsU https://www.youtube.com/watch?v=XRr1kaXKBsU
  - Asraelite 5y ago
    Then what about just orbiting around it? It would just need to be big enough to not cause strong tidal forces.

sombremesa 5y ago

The solar system is traveling in space and is quite massive but I haven’t been crushed to death yet.

smnrchrds 5y ago
You are far away from the masses. We are alive because we only experience 1g on earth. 10g is enough to kill a human. I don't even know what 14,000,000,000,000g would do, but I imagine we would get added to the neutron star.
- IIsi50MHz 5y ago
  1g towards Earth's center. Well, center of mass. :adjusts bow tie: Welllll…combination of that and angular momentum. Combined with the masses of the sun, and the moon, the other planets, and all the other masses of the universe. Fortunately, orbits factor in, too. Everything that orbits is essentially in free fall, wellll…until they get tooo eliptical and the oscillating accelerations get really noticeable. And it all affects time. Time is a bunch of wibbly-wobbly…stuff. (( Ok, ok: Matt Smith might not have been that wordy as The Doctor. ))

brendyn 5y ago

If we could somehow make it into a donut planet we could presumably sit in the middle of it experiencing no acceleration. Would the time dilation effects still occur then?

unlaxedneurotic 5y ago
I don't think so. As I understand it, gravity and acceleration are equivalent, if you aren't experiencing any acceleration then time dilation won't occur. (Assuming we are not traveling near the speed of light)
- darken 5y ago
  One of the more mindbending things to wrap your head around is that gravity isn't a force (i.e doesn't not cause acceleration in the F=Ma sense.). You're simply on a path through spacetime warped by gravity. Think about it: when you are in free fall you feel 0 acceleration. You appear to be accelerating relative to the ground-- but you're actually motionless in an "inertial reference frame". (Similar to how the astronauts on the ISS don't "feel" acceleration despite accelerating rapidly relative to the earth.) The "force" of gravity is often modeled as "gravity pulling you down" and the ground "pushing you back up". This works mathematically, but isn't quite logically consistent. In reality, on the ground you're in a region of warped spacetime, so you feel constant upward acceleration despite not actually accelerating. (Thinking of this another way, standing on earth feels identical to being in a far away spaceship accelerating at 9.8 m/s².) This is also why time "speeds up" near more massive objects. (Separate from "acceleration".) We're so used to gravity this it doesn't seem weird. But when you consider the fact free-fall is when you're not accelerating... well pondering that from many angles is what ultimately led Einstein to his model of relativity. (This is me trying to condense what could be a 10 minute explanation into a few sentences, so apologies if it's not particularly clear.)
  - badocr 5y ago
    The Veritasium youtube channel has a great video about this: https://www.youtube.com/watch?v=XRr1kaXKBsU https://www.youtube.com/watch?v=XRr1kaXKBsU
- Asraelite 5y ago
  Then what about just orbiting around it? It would just need to be big enough to not cause strong tidal forces.