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The Schwarzschild Defence (nature.com)
172 points by bookofjoe 10 months ago | hide | past | favorite | 85 comments

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.

In Altered Carbon, criminal punishment was making that criminal "sleep" (well, destroying his body, keep his memory/conciousness and resleeve him later) for many decades, waking up at a time where he knows no one, and his knowledge was totally outdated. Putting someone into stasis for long would fit into that idea of punishment, and should be a crime by itself, who cares if your wife is alive or dead if she won't be there for the rest of your life anyway?

The bubbles in Vinge's story send people to a future they don't know, and that may be hostile or deserted (I think he wrote a sequel with that idea).

In Marooned in Spacetime we have a set of people who hoped for a better Tomorrow and some rich tourist types who wanted to see what happens in the future come out of stasis to find the Earth deserted. No war, no plague, no apocalypse, just fucked off.

They bubble forward a bit, just in case everyone took a timeout (maybe a toxin was released and there’s a cave full of bubbles waiting for the earth to repair, who knows), but only a few new people show up. Not even enough to repopulate the species. The weird thing is that your status is determined by where you left from not how rich you are. A powerful family skips forward and finds themselves lower status than a group of lower-upper class people with what amounts to top of the line camping gear, which is so much newer than the family’s gear that everything it can do it does better than theirs.

There’s one reclusive person who basically has a space ship. She has been away from humans so long she is barely human (relatable) anymore. She goes out to check other solar systems and finds nothing there either.

The implication is that either we gave up or we ascended somehow, but since they can only travel forward there’s no way to know. They missed the boat.

I think about this book really often, especially the 9,000 year old woman. Really amazing imagery.

> However, they do know that the stasis bubble containing Alice will eventually open up and pop Alice back into the current time.

In the first book, IIRC, they did not know that, and in fact believed the spheres would last forever.

The spheres were used like nukes, in a very indiscriminate way. Whole armies were sphered in a short time.

Many years after, when the first sphere popped, they realized a new way of time travel just opened.

> Whole armies were sphered in a short time.

Yes, till it got easy to make the bubbles. All you have to do to prevent being bubbled, was to carry a bubble. Doesn't prevent cutting you in half though, assuming they guessed the right half, so you might want to carry a few.

Yes, I definitely remember that. Whole cities were carved out from the ground. And didn’t the bubbles also appear to be weightless? Or massless? And would float? I remember thinking at the time that they kinda reflect everything, including gravity, though the book probably had a better explanation that I don’t remember.

The bobbles retain their mass. There is a scene in the book where a bobble floats aways because it was created during the day, and at night the surrounding air cools enough for the bobble to effectively become a hot air balloon.

As far as I know, the book doesn't cover if the bobble retain their angular momentum or charge.

There's a vivid scene where they create a tiny bobble above a candle to catch the hot air.

I always wondered if creating a bobble around an off-center weight would allow you to kind of spin it by wobbling it.

There were some places where large pieces of land unbobbled without any relative movement, so maybe they were locked in their rotation somehow?

I really liked that book a lot.

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.

No, Bob’s put into stasis until Alice is out of stasis, and then he is tried for the appropriate crime. I suppose you could say that the minimum sentence is losing the same amount of time that Alice lost with her loved ones.

There is also the interesting question, what if Alice was never in the bubble in the first place?

> 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.

This is not how double jeopardy works.

By all means, sentence Bob for kidnapping, stick him in jail, have him get out, put a tracker on him and forbid him to leave the country. Then, when Alice pops out and is dead, you just trial him again. It's a different crime! What's more, even if it was the same crime, it'd be material new information!

(Quoth the ECHR: "The provisions of the preceding paragraph shall not prevent the reopening of the case in accordance with the law and penal procedure of the State concerned, if there is evidence of new or newly discovered facts")

Thats great, but the ball pops and its not Alice there.

You jailed Bob for years for the crime he didn't commit. Are you happy?

If it's not Alice there, bubbling Bob was also an injustice.

What would be the difference between this futuristic case and: - Bob kidnapping Alice - Alice not being found - Bob's guilt of the kidnapping is proven in court

Bob could claim e.g. that she escaped after being kidnapped and he's no longer aware of where she is.

Alice's dead body can still be found at some point, which could prove that Bob killed Alice; or she can be found alive, but because of any reason did not want to be found.

Why regressed? You sure can trial them for either kidnapping or murder. But first do the same thing to them they did to the victim, and then you also know for what to trial them. Sounds fair and makes total sense to me.

> 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?

Vinge posits a technology that is used for good and bad purposes. One of the protagonists is a cop who is bobbled by a criminal and emerges in the distant future, when the Earth is essentially uninhabited except for a handful of humans who have been bobbled (electively or not).

>for whatever the name is

Involuntary time travel VS involuntary murder.

I’m curious how voluntary murder works

I think the legal term voluntary means the assailant willed the action taken. For example, first-degree murder involves forethought and a desire to see the victim dead. Involuntary murder or manslaughter covers accidents without malice.

I recommend just reading the books, they're pretty entertaining (in particular, "Marooned in Realtime"). Has some of the best near-singularity tech I've seen.

Ray Kurzweil claims to have invented the Singularity. Ray Kurzweil is full of shit. Marooned in Realtime came out in 1986. Ray didn’t start talking about this stuff until the mid 1990’s. If anyone invented it, it was Vinge.

He’s retired now but he was a professor of CS and Math at San Diego State.

Yes, I read real names in high school and am quite full of a) how prescient vinge was and b) how vapid kurzweil is

What if the guilty party wasn't guilty? Isn't that like putting someone in prison for life on the expectation that eventually evidence will come to light that it was the right call?

This is a major plot point in the stories, that and criminally bobbling someone to get them out of the way.

If you thought your accountant was about to become an informant, bubble him up.

Catch your crime boss enemy with his pants down? Bubble him and watch his empire unravel.

Someone sleeping with your wife? Bubble.

Thus the habbit of carrying a bubble. You can't bubble a bubble, however if you carry just one someone could cut you in half in spite.

How would they determine the guilty party or would it be a case of putting all the suspects into stasis?

Well it’s science fiction not a model for the Rule of Law, so there’s some hand waving to get back to the story at hand. To prove a murder without a body today you need a lot of corroborating evidence. Bodies make everything easier.

He only goes as far as he does because his protagonist in the second book is a detective (and a victim).

Schrödinger's ball of stasis

Sure, it's infinite time, in some framework, until the horizon is reached.

But it's finite time (an assertation left as an exercise for the reader) until murder .. when the tidal forces tear the husbands atoms asunder.

Yes! That, and the gamma-rays being emitted by all the falling matter. That’ll kill the husband way before he gets close.

But I love the story. Clever use of time dilation.

I thought this too until the most recent xkcd book taught me that if a black hole is big enough it's actually possible to pass through the event horizon without getting torn apart. It's a question about soup. Good stuff.

The story says the black hole was "wreaking havoc in the Kuiper belt," which implies that it's not very big (else it would be wreaking havoc in the entire solar system). So spaghettification on a human timescale is quite possible!

P.S. I love this discussion

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.


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 hit the event horizon (and then the singularity). It just takes infinitely long time for that energy to escape.

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.

So as you fall down the black hole, the objects in front of you will start getting less red-shifted and brighter as you begin matching velocities with them.

But nothing special (for you) happens at the event horizon.

The images of objects that fell before you, will just continue to become brighter and brighter. In fact you'd even be able to communicate with somebody who just fell in in front of you.

But you don't have a lot of time before the singularity. So you won't catch up with _everything_ that fell before you, and the amount of energy that you absorb from their fading echoes will not be infinite. It won't even be that large.

What will get you, is the fact that this finite amount of energy will get concentrated into an infinitely thin and infinitely bright band at the singularity.

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/startswithabang/2018/01/19/what...

Yup. But if you're a free-falling point-like observer then you won't be able to find this out. You'll only discover this if you try to send a signal out or fire your ship's engines.

And of course, at some point the tidal forces would be so large that any non-point-like observer would be torn into pieces.

The possible directions that you'll see actually become constricted to a line, not a point. It's essentially a projection of the time axis. That's because in a classical theory singularity exists as an infinitely long time-like line. As you fall down, you can influence the location where you hit it a bit if you fire your ship's engines.

But anywhere on this line the gravity (curvature) is still infinite so it's not like you'd be much better off.

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.

> 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.

>But nothing special (for you) happens at the event horizon.

I smiled as I read this and recalled that old saw attributed to someone's high school coach: "Nothing good happens after midnight."

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.)

> When you fall feet first into a black hole [...] which you cross at the speed of light.

I don't know where you're getting this but nothing with mass can reach the speed of light. And it's absolutely possible to cross the event horizon (of a very large black hole) without having any idea whatsoever. There would be no particular event to happen that would indicate to you that you did.

>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.

In our neck of the multiverse we call this death.

Who's to say it's not a fact?

If you enjoyed xkcd on black holes, you might also enjoy this talk:

Black Holes and the Fundamental Laws of Physics


Since they discuss deliberately skimming the event horizon, I assumed that there were some form of protections against that (perhaps they no longer inhabit biological bodies, which would increase the available options).

Even if it weren't classified as murder, I think they could at least charge with attempted murder.

This is also the premise of the novel Gateway by Fredrik Pohl. https://en.wikipedia.org/wiki/Gateway_(novel)

Hoo boy, the first Gateway book really stuck with me. It really hit me when the protagonist explained their suffering. Even if it's decades later for you, how can you get over something or forgive yourself for it if, for them, it's still happening. “She's thinking I betrayed her, and she's thinking it now!"

They need to make a remake of this game ;)


Not a lawyer, but doesn't the direct and intentional actions (sabotage of the steering) by the narrator put Xaiver into a position that would ultimately end in death (with no possible escape or rescue), then the time it takes to achieve that is irrelevant from a law perspective. It was first degree murder.

If the FBI created a sting wherein they gave you a gun you thought was real, but wasn't actually capable of firing, and you pointed it at someone and pulled the trigger, you could still face a murder a charge even though there was no way the gun would do any harm. It was your intent followed by action to achieve that intent that mattered.

As I had the introduction of the Murder chapter in a criminal law textbook explained to me, "Death is inevitable. So what we are really talking about here is acceleration."

Since the victim's demise here was decelerated, at least from the point of view of everyone in the trial, it can't be murder. Maybe some kind of kidnapping.

Interesting, but I would say its the victim's POV that matters. In a relatively short amount of time from his perspective, he will be torn apart by tidal forces or smashed to bits by debris impacts (he can't steer). Even if that time is long, then he'll die of starvation or dehydration when his supplies run out. His life span, from his perspective, is greatly shortened.

I'd rule out kidnapping, because unlawful detainment presumes that the person can be released from that detainment. There is no possibility of release for Xavier.

> I'd rule out kidnapping, because unlawful detainment presumes that the person can be released from that detainment. There is no possibility of release for Xavier.

False imprisonment seems to fit:

To prevail under a false imprisonment claim, a plaintiff must prove:

Willful detention in a bounded area

Without consent; and

Without authority of lawful arrest. (Restatement of the Law, Second, Torts)

neat story, but since when did nature branch out to publishing short stories? roots about the website 2000??


That's the most recent set, but they've had a long history of publishing fiction and speculation in addition to research papers. It's important to remember that Nature is a bit of an oddity among scientific publications (although its American equivalent Science is somewhat similar) in that it is really two publications in one -- the journal part where it publishes papers, and also a magazine about science where non-papers get published -- news stories, book reviews, obituaries of famous scientists, and yes, sometimes fiction as well.

It’s a magazine. Many magazines have a readers’ letter section, an opinion column, a short story, … and in case of science magazines, the short stories are traditionally science fiction.

Yet another reason why having a black hole within the solar system is a bad idea.

This reminds me of the kind of fiction that would be in Omni Magazine.


What frame of reference does the Justice system see as canonical?

Unlawful restraint of person

My thoughts exactly. But it's a tricky argument as well, because from the point of view of the victim, they're not actually being restrained.

> Once he turned towards the black hole, the controls locked. He can’t turn back anymore. He can only fall.

Death’s end by Cixin Liu employed a similar plot device . A great read.

I'll admit that I preferred the first two books in the trilogy.

But it was a very interesting ending!

For some reason that reminds me of this totally unrelated animation, "To Be" about teleportation from the 80s


This was a fun short read!

Sounds like something from The Illustrated Man, by Ray Bradbury.

A "video representation" of the sabotage is still traveling through space and someone with a good telescope can pick it up.

There is a huge mistake in this reasoning! Time dilation goes to infinity at the center of the black hole - at the singularity, not at the event horizon! The event horizon could be millions of miles (many AUs) away from the singularity. Near the event horizon, her husband is likely to be falling rapidly into the black hole and is not going to be stuck indefinitely. So, it's Murder 1, immediately.

> Time dilation goes to infinity at the center of the black hole - at the singularity, not at the event horizon

That is incorrect. The inside and outside of the black hole are causally disconnected. For someone who passes the event horizon the entire future history of the universe plays out above them as the universe warps down into a single beam of light as the black-ness engulfs you.

From the perspective of someone outside, nothing ever "crosses" the event horizon - it just slowly redshifts into darkness and appears to take infinity to "touch" the even horizon.

There is nothing "happening" inside of any black hole right now that has any corresponding time in the outside universe. From our perspective, it happens in the infinitely far future.

"For someone who passes the event horizon the entire future history of the universe plays out above them"

I believe this is only true if you have found a way of lingering with zero speed at the event horizon. If you are entering it at near light speed, as you likely would, you will be ingested as a part of "treadmill" containing yourself as well as all the light and will not see much of the future history.

Think of it this way: 1) the closer to the speed of light the bigger difference between your time frame and an external observer's. 2) at the speed of light the universe will age to infinity as you watch 3) inside the event horizon, even the speed of light is not enough to escape.

For an external observer you'll appear to slow down as you approach the event horizon. However feeding blackholes do increase is size obviously (or they would all be the same size), which may well save you from the (from an external perspective) an infinite descent.

> There is a huge mistake in this reasoning!

No there isn't. As far as external observers are concerned, an object falling into a black hole takes an infinite amount of time to cross the event horizon. It vanishes from sight because its emissions get red-shifted beyond detection range, but in principle you could still see it however far in the future you care to go, "frozen" in place over the horizon, still approaching it asymptotically.

Not a physicist, but Wikipedia seems to disagree with this.

> Due to this effect, known as gravitational time dilation, an object falling into a black hole appears to slow as it approaches the event horizon, taking an infinite time to reach it


Or have a twin sibling. They can never convict you or your sibling.

> That’s all there is, Detective. Clearly, there’s been no murder. Inconvenience, probably, but has he actually said so? Is he pressing charges? I didn’t think so.

This seems like the kind of "clever" legal defense that I expect judges in the real world would probably shoot down real quick though.

Even without a black hole or stasis tech, you could attempt, a similar situation occurs e.g. with people in coma. Someone who injured a person badly enough that he is in coma could also try to argue "Your honour, the person never said he is uncomfortable with the situation, you can go right ahead and ask him..."

I don't think that would be very convincing.

On the contrary - if you say that with confidence in front of a crowd that is hanging on your every word, that's a winning chess move. Sometimes, rarely. Maybe only once.

Writing quality is not great and you coule BLUF the whole piece without losing anything.

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