# Tag Info

Accepted

### Does the cosmological constant entail a mass for the graviton?

No, you don't get a mass term in the propagator, and there is no graviton mass for GR with a cosmological constant. If you linearize about Minkowski space, $g_{\mu\nu}=\eta_{\mu\nu}+h_{\mu\nu}$, then ...
• 51.1k
Accepted

### What Does Feynman Mean When He Says Amplitude and Probabilities?

I think the confusion starts from an interpretation of quantum mechanics I have seen many times applied to atomic orbitals or Young's double-slit experiment (YDSE). In the former case the electron has ...
• 35.4k
Accepted

### Is the size of a black hole singularity smaller than a fundamental particle?

The very short answer to this is: We have no idea. General relativity predicts that the singularity of a Schwarzschild black hole (which I assume is what you mean by "actual black hole") is ...
• 1,897

### Is the size of a black hole singularity smaller than a fundamental particle?

While @paulina's answer: we don't know is correct, because quantum gravity is not understood, I'll answer for a classical Schwarzschild blackhole as described by Kip Thorne. The size is zero, however ...
• 35.4k

### Is the size of a black hole singularity smaller than a fundamental particle?

We know that black hole is infinitely densed. More exactly: The theory of general relativity predicts that the center of a black hole is infinitely dense. This theory predicts very well everything ...
• 40.1k

### Can you calculate the radius of a hypothetical singular surface inside a black hole from observing changes to its linear momentum?

No, because as an observer outside the event horizon, you will never be able to see an object cross the event horizon. (See This post)
Another option for finding the Hawking temperature of the BTZ black hole is by the formalism of the surface gravity $\kappa$ which connected to the Hawking temperature via: $$T_H=\frac{\kappa}{2\pi}$$ ...