Why is it thought that black holes could make us travel to the past?

[Etherealist]

I very often see in movies and works of fiction that scientists explain that with a black hole you can travel in time and how the characters use black holes to travel in time, more precisely to the past

Do scientists really believe that time travel through black holes is likely? If so, why?

 

[Dale]

No. Those are fictional scientists. Their statements are for plot convenience, not education.

 

[Demystifier]

A more technical answer is this. Maximal extension of the simplest eternal black hole solution (Schwarzschild solution) has a non-traversable wormhole. Such an eternal solution is not physically realistic because the realistic black hole forms through gravitational collapse, so is not eternal. And even if it was realistic, the non-traversable wormhole, as its name suggests, cannot be used for travel. Nevertheless, it's easy to ignore the "non-traversable" stipulation and fantasize what would happen if black hole contained a wormhole which was traversable. Mathematically, it is possible to imagine wormhole geometries which allow time travel, under certain conditions perhaps even to the past, which is where the inspiration for SF stories of this kind comes from. In fact, I think the first SF story using a wormhole for space travel was "Contact" by the astrophysicist Carl Sagan, who used the idea of wormholes suggested to him by the physicist Kip Thorne.

 

[pinball1970]

A more technical answer is this. Maximal extension of the simplest eternal black hole solution (Schwarzschild solution) has a non-traversable wormhole. Such an eternal solution is not physically realistic because the realistic black hole forms through gravitational collapse, so is not eternal. And even if it was realistic, the non-traversable wormhole, as its name suggests, cannot be used for travel. Nevertheless, it's easy to ignore the "non-traversable" stipulation and fantasize what would happen if black hole contained a wormhole which was traversable. Mathematically, it is possible to imagine wormhole geometries which allow time travel, under certain conditions perhaps even to the past, which is where the inspiration for SF stories of this kind comes from. In fact, I think the first SF story using a wormhole for space travel was "Contact" by the astrophysicist Carl Sagan, who used the idea of wormholes suggested to him by the physicist Kip Thorne.

As Jodie Foster's character, Ellie, goes through the worm hole we see her as a mixture of future and present events like causality has been messed with.
Interstellar, has the inside of the black hole as a series of past events as compartments, Cooper can go to where he can communicate with Murph in the past in his present....
Sci fi but fun!

 

[PeroK]

I can't say I've ever subjected myself to a feature film involving a black hole. Kubrick's Space Odyssey and Tarkovsky's Solaris are the closest I've come.

 

[pinball1970]

I can't say I've ever subjected myself to a feature film involving a black hole. Kubrick's Space Odyssey and Tarkovsky's Solaris are the closest I've come.

Interstellar is definitely worth seeing. Kip Thorne was the SA on this film as well apparently.

https://en.m.wikipedia.org/wiki/The_Science_of_Interstellar

 

[pbuk]

I can't say I've ever subjected myself to a feature film involving a black hole.

You are missing out: suspension of disbelief can be entertaining.

Edit: although the "compartment" thing at the end of Intersteller was a bit of a stretch for me, even though it was a great plot device.

 

[PeroK]

You are missing out: suspension of disbelief can be entertaining.

Edit: although the "compartment" thing at the end of Intersteller was a bit of a stretch for me, even though it was a great plot device.

It's not about suspension of disbelief. One of my favourite modern films is Crouching Tiger, Hidden Dragon. It's the crassness and lack of imagination of the blockbuster movie.

 

[pinball1970]

It's the crassness and lack of imagination of the blockbuster movie.

"The blockbuster" is fairly broad. I do not want to derail the thread. Perhaps a small post in Arts.

 

[Demystifier]

I can't say I've ever subjected myself to a feature film involving a black hole. Kubrick's Space Odyssey and Tarkovsky's Solaris are the closest I've come.

So you watch only hard core SF.

 

[PeroK]

So you watch only hard core SF.

I've seen four Tarkovsky films: Ivan's Childhood, Andrei Rublev, Solaris and The Mirror.

I've seen all Kubrick's major films, except Barry Lyndon.

 

[berkeman]

[Thread moved from the Relativity technical forum to the SciFi forum]

 

[Hornbein]

It's not about suspension of disbelief. One of my favourite modern films is Crouching Tiger, Hidden Dragon. It's the crassness and lack of imagination of the blockbuster movie.

I liked that one. Asian people seem more demanding of logical plots than the West, where all too often the plot is merely a thin excuse for car chases and fist or gun fights.

 

[Ivan Seeking]

There is a solution from GR that allows a spacecraft to circumnavigate a black hole, and exit orbit at the same moment they enter orbit, or nearly so. IIRC this is a consequence of frame dragging.

 

[Ivan Seeking]

There is also a solution that allows for massless black holes traveling at the speed of light. But that's another story. :)

 

[mpresic3]

I very often see in movies and works of fiction that scientists explain that with a black hole you can travel in time and how the characters use black holes to travel in time, more precisely to the past

Do scientists really believe that time travel through black holes is likely? If so, why?

I think that currently scientists do not believe that time travel through black holes is possible. I have read that it would negative energy, whatever that is, and maybe a spinning black hole, Spinning black holes do exist, something like closed timelike curves, etc, and other exotic concepts.

Where most scientists do not believe it is possible, Many will not say it is impossible. Scientists are known for their open minds. Time travel without black holes would be even more unlikely, so fiction writers use this mechanism in their stories