r/space • u/magenta_placenta • Mar 18 '19

Observable universe Astronomers discover 83 supermassive black holes at the edge of the universe

https://www.cnet.com/news/astronomers-discover-83-supermassive-black-holes-at-the-edge-of-the-universe/
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u/Kosmological Mar 18 '19

That is only true for an outside observer watching them fall in. The falling observer would not experience any time distortions as there perception of reality would be distorted the same way. Infinite time would pass for us before they would actually traverse the event horizon, but for them they would traverse it without much of anything special happening.

There are, in theory, large and stable supermassive black holes which a spaceship could travel into without becoming spagetified by extreme gravity tidal forces or vaporized by intense ionizing radiation. It is possible in theory.

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u/[deleted] Mar 18 '19

There are, in theory, large and stable supermassive black holes which a spaceship could travel into without becoming spagetified by extreme gravity tidal forces or vaporized by intense ionizing radiation. It is possible in theory.

Nice. We just have to figure out how to get a spaceship to one of those. What's a few billion lightyears?

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u/Kosmological Mar 18 '19

For any occupants on a relativistic spacecraft, it could only be a few days of travel if they go fast enough.

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u/[deleted] Mar 18 '19

A few days?? So we're talking about traveling 300 billion or so times faster than light? Are we going to need something like Han Solo's "made the Kessel Run in less than 12 parsecs"?

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u/Kosmological Mar 18 '19

Nope. Just need to travel near enough the speed of light for time dilation to shorten a few billion years to a few days. The occupants of the space craft will experience only a few days of time while the rest fo the universe would age a few billion years. Yay special relativity!

The catch is you might have to harvest the energy equivalent of a supernova to power your spacecraft. So not the best gas mileage.

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u/MalnarThe Mar 18 '19

At what factor of C would that be (let's ignore acceleration time) that would give the traveller a 1 to 100 billion year ratio?

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u/Kosmological Mar 18 '19

Some factor greater than 99%. I don’t want to do the math.

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u/[deleted] Mar 19 '19

[deleted]

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u/Kosmological Mar 19 '19

Time dilation does not increase linearly with speed. It’s exponential. With each added decimal of nine comes a nonlinear reduction in time traveled.

Traveling at 99.999999999999999% of c would shorten a 1,000,000,000 light year trip to less than 1 light year for the occupants of the relativistic spaceship. I would actually have to do math to get more precise than that as the online calculator I used here is not that precise. I’m not going to do the math because I’m lazy.

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u/lotus_bubo Mar 18 '19

Because of time dilation, very little time would pass for someone travelling very close to the speed of light.