I will publish patent application and I want to share my invention with others right after that. I want to see if there will be any interest from investors. Are there any dangers associated with such a disclosure (as the priority date is granted already)?
If you were to file another application claiming priority from the first patent application, and you were to further add new embodiments in that another application, then the publication of the white paper will be prior art against those new embodiments in countries/regions where you do not have a grace period. This means that claims directed to those new embodiments might not be novel or non-obvious over your white paper.
There are many factors that should be taken into account when deciding whether the publication is a good idea or a bad idea: the patent application itself, the technology of the invention, competitors, business model, etc.