Can a Running Tap Water Basin Be an Analogy for a Black Hole Event Horizon?

AI Thread Summary
The discussion explores the analogy between a running tap water basin and a black hole's event horizon. The original poster suggests that water swirling in a basin represents light trapped at the event horizon, unable to escape or enter. However, participants clarify that water can flow down the basin and that the analogy is flawed, as light does not hover but rather crosses the event horizon. They also mention that light emitted at the horizon can still reach the singularity, contrasting with the proposed analogy. Ultimately, the consensus is that the analogy does not accurately represent the nature of a black hole's event horizon.
shounakbhatta
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Hello,

I am trying to draw an analogy, which just came with a flash in my mind. Please clarify me, if it is wrong. Kindly note that it is an analogy only.

An event horizon -- Where the light emitting is not strong enough to go inside the black hole also it cannot go outside the zone and keeps on hovering around.

If I open a tap water and the water gushing down the basin creates a spherical form. The water neither can flow inside the basin, nor it can go outside.

Is it this which can be thought of a black hole event horizon?

Please correct me if I am wrong.

Thanks.
 
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shounakbhatta said:
If I open a tap water and the water gushing down the basin creates a spherical form. The water neither can flow inside the basin, nor it can go outside.
I don't follow you there at all. Of course the water can flow down. Why would it not?

Also, it would not be a spherical form, it would be a circular form.
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Also, light readily enters a black hole. The only light that is trapped is light emitted at the horizon in the radial outgoing direction. All other light emitted at or in the horizon reaches the singularity (in the simplest BH). Further, all light heading toward the BH, crosses the horizon and reaches the singularity.
 
There is another analogy that has drawn significant scientific interest. It is called an acoustic black hole. IIRC one was created not long ago using an Bose-Einstein condensate.
 
My question was trying to understand how an event horizon looks like? My analogy of water flowing down is that the light which hovers around the 'event horizon' of a black hole, can that look like the water which forms a border on the basin?
 
The short answer is ... No.
 
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