Black Hole Event Horizon: Is There a Physical Boundary?

[ChrisVer]

Is there a physical boundary that is the event horizon? Or is there not?
The reason I'm asking is because texts say that the event horizon that appears in Schwarzschild's metric is a result of the coordinate choice, and it disappears by choosing some other coordinates.

 

[A.T.]

The reason I'm asking is because texts say that the event horizon that appears in Schwarzschild's metric is a result of the coordinate choice, and it disappears by choosing some other coordinates.

I think what they say is that the singularity at the EH exists only in some coordinates.

 

[Nugatory]

Is there a physical boundary that is the event horizon? Or is there not?
The reason I'm asking is because texts say that the event horizon that appears in Schwarzschild's metric is a result of the coordinate choice, and it disappears by choosing some other coordinates.

The singularity at the horizon is a result of coordinate choice (you can make it go away by choosing, for example, Kruskal coordinates) but the physical significance of the event horizon is not. The event horizon is a light-like surface, and "physical boundary" is not an especially natural term for describing it, but it is a well-defined surface in the Schwarzschild spacetime as long as you use coordinates that aren't singular there.

 

[George Jones]

The reason I'm asking is because texts say that the event horizon that appears in Schwarzschild's metric is a result of the coordinate choice, and it disappears by choosing some other coordinates.

I have never encountered a text that says this.

 

[ChrisVer]

I have never encountered a text that says this.

That's a coordinate singularity. It exists due to the choice of coordinates, and can be resolved by a more appropriate choice of coords.

 

[Ibix]

At risk of putting words in George's mouth, I think he's pointing out that a coordinate choice doesn't remove the event horizon, which is a co-ordinate independent surface. You can remove the coordinate singularity at the event horizon by careful choice of coordinates, but the horizon remains.