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The Schwarzschild Defence

nature.com

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Re: The Schwarzschild Defence

#21

Post by gorgoiler »

cyberax wrote: post #17
pontifier wrote: post #16

Earlier quoted context omitted.

I saw a very interesting lecture on YouTube about what you'd see as you fall through an event horizon. Basically you catch up to everything that has ever fallen into the black hole before you. My guess is that it would look like another big bang. https://youtu.be/BdYtfYkdGDk?t=4126

Not quite. A fixed observer far away from a black hole sees that objects falling into the black hole become more and more faint, and move towards horizon ever so slower. In a classical situation with a good enough detector you can see the images of ALL the objects that fell into the black hole. But this is merely an optical illusion. Objects that fall into the black hole emit only a fixed amount of energy before they…

And if you fall in feet first you see your feet like a flatbed scanner scans an image.

When you stand still on Earth, photons from your feet move at light speed into your eyes. When you fall feet first into a black hole, they emit stationary photons on the event horizon, which you cross at the speed of light. It’s all c to you though.

(I’m halfway through Cox and Forshaw’s Black Holes: The Key to Understanding the Universe. It’s really good — undergrad relativity written as a pop sci book. I think I’ve understood it so far.)

Re: The Schwarzschild Defence

#24

Post by doctor_eval »

skrebbel wrote: post #20
hinkley wrote: post #8

Vernor Vinge’s Peace War has balls of stasis, which you can’t see in to tell if the person trapped is alive or dead. So when they figured out how to calculate the lifetime of the bubble, they started putting the guilty party into a bubble timed so they both popped at the same time, which would quickly be followed by your court date if it turned out to be murder.

This sounds really interesting but I have absolutely no idea what you mean. Is the ball the same as the bubble? Why does someone go into it? Who is the “guilty party”?

I think - it was a very very long time ago when I read this - but a bad person can put someone into a stasis field without their consent. The stasis field is the shape of a perfect bubble or ball. IIRC it's also perfectly reflective. Anything inside the stasis field simply doesn't participate in time.

Once Bob puts Alice into statis, the stasis ball is impenetrable, so the cops don't know if Alice was alive or dead when she was involuntarily put into stasis.

However, they do know that the stasis bubble containing Alice will eventually open up and pop Alice back into the current time. And they know when that will happen. So, the state puts Bob (the guilty party) into stasis too; with Bob's stasis timed to end when Alice's ends.

In this way, both stasis fields pop at roughtly the same time, and Bob can be tried either for murder, or for whatever the name is when you transport someone into the future against their wishes.

Re: The Schwarzschild Defence

#26

Post by pa7x1 »

pontifier wrote: post #18
cyberax wrote: post #17

Earlier quoted context omitted.

Not quite. A fixed observer far away from a black hole sees that objects falling into the black hole become more and more faint, and move towards horizon ever so slower. In a classical situation with a good enough detector you can see the images of ALL the objects that fell into the black hole. But this is merely an optical illusion. Objects that fall into the black hole emit only a fixed amount of energy before they…

I believe there's a directionality component that happens when you fall into a black hole as well. The directions out of the black hole begin to constrict into a point above you, while directions that end at the singularity become more and more spread out, until every direction leads to the singularity as you cross the event horizon. Edit: this Forbes article describes this effect. https://www.forbes.com/sites/starts…

It's not every direction that points into the singularity inside the event horizon. It's time itself that points to the singularity, hence why it's inevitable to fall into the singularity in a Schwarzschild BH.

Re: The Schwarzschild Defence

#27

Post by codeflo »

doctor_eval wrote: post #24
skrebbel wrote: post #20

Earlier quoted context omitted.

This sounds really interesting but I have absolutely no idea what you mean. Is the ball the same as the bubble? Why does someone go into it? Who is the “guilty party”?

I think - it was a very very long time ago when I read this - but a bad person can put someone into a stasis field without their consent. The stasis field is the shape of a perfect bubble or ball. IIRC it's also perfectly reflective. Anything inside the stasis field simply doesn't participate in time. Once Bob puts Alice into statis, the stasis ball is impenetrable, so the cops don't know if Alice was alive or dead w…

I still don’t get it. So in this fictional universe, has the legal system regressed to the point where kidnapping someone for (presumably) decades is no longer a crime with a life sentence?

Or alternatively, is the point that you can’t be punished for kidnapping if you might also have murdered the person, but that part can’t be proven? None of that makes sense.

Re: The Schwarzschild Defence

#28

Post by justsomehnguy »

doctor_eval wrote: post #24
skrebbel wrote: post #20

Earlier quoted context omitted.

This sounds really interesting but I have absolutely no idea what you mean. Is the ball the same as the bubble? Why does someone go into it? Who is the “guilty party”?

I think - it was a very very long time ago when I read this - but a bad person can put someone into a stasis field without their consent. The stasis field is the shape of a perfect bubble or ball. IIRC it's also perfectly reflective. Anything inside the stasis field simply doesn't participate in time. Once Bob puts Alice into statis, the stasis ball is impenetrable, so the cops don't know if Alice was alive or dead w…

>for whatever the name is

Involuntary time travel VS involuntary murder.

Re: The Schwarzschild Defence

#29

Post by justsomehnguy »

codeflo wrote: post #27
doctor_eval wrote: post #24

Earlier quoted context omitted.

I think - it was a very very long time ago when I read this - but a bad person can put someone into a stasis field without their consent. The stasis field is the shape of a perfect bubble or ball. IIRC it's also perfectly reflective. Anything inside the stasis field simply doesn't participate in time. Once Bob puts Alice into statis, the stasis ball is impenetrable, so the cops don't know if Alice was alive or dead w…

I still don’t get it. So in this fictional universe, has the legal system regressed to the point where kidnapping someone for (presumably) decades is no longer a crime with a life sentence? Or alternatively, is the point that you can’t be punished for kidnapping if you might also have murdered the person, but that part can’t be proven? None of that makes sense.

> kidnapping someone for (presumably) decades

Presume Alice was 'kidnapped' in the ball for XX years. You trial Bob and sentence him for 20 years. 20 years passes, Bob serves his sentence and some time later it occurs what Alice were dead all these years, but Bob not only left the country but served his sentence.

Or you sentence Bob for the murder of Alice (even better - execute him), yet Alice is alive, though 20 years later.

Thing is, till the bubble pops you don't know for what exactly you should punish someone and hence - how hard and harsh.

It's a classical dilemma of bringing in/justice with the lack of means to prove anything.

There was a short story in a similar vein with a 'light retarded glass', ie glass what slowed the passage of light through it for times. It were essentially a CCTV/DVR with a years to retrieve 'the record'. The protagonist of the story waited for ~decades waiting to confirm if he sentenced the culprit rightfully for murder or he murdered innocent person with the state authority. Maybe someone would remember what was the name of this story.

Re: The Schwarzschild Defence

#30

Post by krisoft »

cyberax wrote: post #17
pontifier wrote: post #16

Earlier quoted context omitted.

I saw a very interesting lecture on YouTube about what you'd see as you fall through an event horizon. Basically you catch up to everything that has ever fallen into the black hole before you. My guess is that it would look like another big bang. https://youtu.be/BdYtfYkdGDk?t=4126

Not quite. A fixed observer far away from a black hole sees that objects falling into the black hole become more and more faint, and move towards horizon ever so slower. In a classical situation with a good enough detector you can see the images of ALL the objects that fell into the black hole. But this is merely an optical illusion. Objects that fall into the black hole emit only a fixed amount of energy before they…

> And in general, there's no way for the observer to tell if the falling ship is falling towards the black hole or merely accelerating under its own power.

That’s it. I’m getting a “not accelerating towards black holes” bumper sticker for my ship. I might die a sphagetti, but people will not think that I was foolish. That will clear up any ambiquity.

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