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Given the effects of gravitational time dilation, a person falling into a black hole would take an infinite amount of time to cross the event horizon. But black holes don't last forever due to Hawking radiation, so by the time a person got close enough to the event horizon, wouldn't the black hole cease to exist?
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Gravitational time dilation affects the observer, not the person falling into the black hole. To the one falling time ticks the same as usual but the one watching them seems them being time dilated 'infinitely'. The light would also be ever more redshifted so at some point you wouldn't be able to see them anyway.
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I've got another question: if black holes very slowly evaporate via hawking radiation, and and eventually explode and cease to exist as the last things in the universe, so where does all that evaporated matter go? Energy cannot be lost, according to the second laws of thermodynamics, so is it just so scattered all over vast universe or what?
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>>15011421
I know that. From the perspective of the person falling into the black hole, time outside would speed up until the entire age of the universe went by when they reach the event horizon, meaning the black hole shouldn't exist anymore.
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>>15011443
Well you got to think about the acceleration factor
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Hawking radiation is bullshut(his last attempt for the noble price) and the trick is to realise to us the black hole doesnt age that fast aswell
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>Hawking radiation is black body radiation
>Black-body radiation is the thermal electromagnetic radiation within, or surrounding, a body in thermodynamic equilibrium
>Thermal radiation is electromagnetic radiation generated by the thermal motion of particles in matter
>particles in matter in an empty universe
what, a bunch of hydrogen? or helium, like alpha radiation?
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>>15011437
>energy cannot be lost
probably true, but ultimately this will either be trivially disproven or will remain forever unfalsifiable.
>last things in the universe
You imply that energy cannot be created. A known property of all mass is that it warps mass etc towards itself. A known property of the only known prior boring universe is that it created more particles than antiparticles until the universe was no longer boring. Consider that whatever conditions which caused the current state of the universe to arise may reoccur in a similar fashion, and that the alternative would be that the laws of reality have or could change. The CMB cold spot is my wife's temperment.
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>>15011437
>so where does all that evaporated matter go?
It is converted into photons.
>so is it just so scattered all over vast universe or what?
Yes, it is scattered as hawking radiation.
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>>15011671
>Consider that whatever conditions which caused the current state of the universe to arise may reoccur in a similar fashion, and that the alternative would be that the laws of reality have or could change. The CMB cold spot is my wife's temperment.

This is my belief as well, it's the most logically congruent.

Otherwise the universe either randomly popped into existence one day, or spent what I assume would have to be an infinite amount of time as a singularity before randomly blowing up.
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>>15011443
This. Everyone always goes "nono, the slowing down is only what an outside observer would see"
Yeah, I know the guy falling in wouldn't feel slow or something. As he nears the EH, time dilates arbitrarily close to infinity, in the same way that a photon crosses the universe in an instant from its perspective.
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>>15011686
Then what happens?
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>>15011443
>From the perspective of the person falling into the black hole, time outside would speed up until the entire age of the universe went by when they reach the event horizon,
No, your brain would slow down on processing your reality, it's illusion and it's stupid to say it your way.
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>>15011771
What the fuck are you talking about?
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>>15011670
selfreply: it's like mostly photons
also eventually black holes will dissipate and explode, releasing all kinds of massive particles
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>>15011404
Hawking radiation is pseudoscience and there’s no evidence that it exists.
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>>15011437
>Energy cannot be lost, according to the second laws of thermodynamics
There is no reason to believe this is true
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>>15011443
No, it wouldn't, what you would see is absolutely nothing, as the gravity would be strong enough to instantly accelerate whatever light crosses the event horizon to the center of the black hole, time is not a physical object that can be manipulated, "time dilation" is just information delay between two or more things, local time is never manipulated or violated in any way
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>>15011736
Well, logically it would follow that back he's are not actually stable structures but are instead rapid implosions folled immediately by an explosion, but dialated to a near standstill from our perspective.

It would evaporate as soon as you were about to cross the EH imo. In fact, the only matter within the EH is the stellar matter that was already within its radius at the time of collapse. All other material drawn to the black hole exists as a hyperthin, redshifted to near black, frozen in time shell just barely outside of the EH.
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>>15012659
In the actual fact there's no EH either, the whole pre-collapse mass is hovering at just above critical density stuck in time dilation, and the material that falls in later is layered around it as a shell. And since there's no EH there's no Hawking radiation either, it's just a normal thermal radiation.
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>>15011421
How can there be a mismatch between observer and the event being observed without something being an optical illusion? Clearly something's wrong with our theories.
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>>15011404
I know (almost) nothing about black holes or general relativity.

but the way I see it, by the time you reach lightspeed the universe ends with you and even if the black hole ceases to exist you are still accelerated to the speed of light.



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