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Salviati

(6,054 posts)
11. They aren't canceled
Sun Jan 14, 2024, 03:50 PM
Jan 2024

In the case of the orbiting object the acceleration is not zero. The object is undergoing a continuous change in its direction, which is an acceleration.

In the case of an object right in between two black holes, those two gravitational forces could cancel out, but if we look at the details of the time dilation between two different points it depends on the difference in gravitational potential, so while the force cancels out, the time dilations would actually combine to get bigger.

The way to visualize it is with the common rubber sheet analogy for thinking about spacetime curved by objects. The gravitational force is represented by the slope of the sheet. The steeper the slope, the stronger the force. If you're a distant observer very far away from an object, the sheet is flat and horizontal.

Time dilation depends on the height of the rubber sheet though, not the slope. The lower the height, the slower a distant observer will see a clock on that object running. At a point midway between two black holes, the sheet may be horizontal, but it will still be at a lower level than a distant observer.

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I thought this was a question about Trump lawyers nt Stardust Mirror Jan 2024 #1
Yeah they definitely are looking for ways to slow down time! Shermann Jan 2024 #2
Planning a little intergalactic trip and want to make it seem longer or shorter? marble falls Jan 2024 #3
Yes. Salviati Jan 2024 #4
Right, but can the effects be canceled out? Shermann Jan 2024 #10
They aren't canceled Salviati Jan 2024 #11
OK so gravitational field strength and gravitational potential are two separate things Shermann Jan 2024 #14
Right, they're different - but related. Salviati Jan 2024 #16
Oh I got them reversed! Oh well. Shermann Jan 2024 #22
I feel that time changes when I stand up. Arne Jan 2024 #5
Does an object ... experience time dilation? sanatanadharma Jan 2024 #6
"Experience" means simply encounter or undergo in this context. Shermann Jan 2024 #7
I "googled" this through Duck Duck Go: stable orbits around black holes and time dilution Backseat Driver Jan 2024 #8
Just for funzies I posed the question to Microsoft Copilot Shermann Jan 2024 #9
Have to be careful about trusting AI Salviati Jan 2024 #12
Yeah Copilot got part of that from the OP! Shermann Jan 2024 #13
What about gravitational tides? Jeebo Jan 2024 #15
Some really weird stuff happens around black holes - even outside of the event horizon. Salviati Jan 2024 #17
Again, pardon my ignorance, but ... Jeebo Jan 2024 #18
By radius here... Salviati Jan 2024 #20
Could you help me find something? Jeebo Jan 2024 #21
That doesn't give a whole lot to go on, and it's not ringing any bells. Salviati Jan 2024 #23
The last time I orbited a black hole, time just stood still, just like it does on the church pew on Sunday morning. Chainfire Jan 2024 #19
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