# I I need a list of all singularities in physics

1. May 1, 2017

### SothSogi

Hi there everyone

I'd like to have a list of all the instances where a singularity appears in physics, e.g., in relativity, causing the black hole thing.

Specific cases where

$$\frac{x}{0}$$

appears.

For instance, I heard that there is another case in quantum mechanics, or quantum field theory, and I think it is called renormalization.

Thank you very much in advance

2. May 1, 2017

### Buzz Bloom

Hi SothSogi:

The Friedmann equation

has a singularity for a=0 which also corresponds to t=0.

Good luck.

Regards,
Buzz

3. May 1, 2017

### SothSogi

Thanks Buzz Bloom. That is exactly the kind of information I am looking for. Thank you very much

4. May 1, 2017

### cosmik debris

This is difficult to do because many singularities are the products of co-ordinate choices. You will have to sift through them all and determine which ones are, and I hate to use the word, real.

5. May 1, 2017

### SothSogi

Yes, I suppose. But here I am talking about well known singularities, like black holes, or that thing, renormalization which I do not know very well. I think there is another called cosmic string, or another called domain wall.