Groups take some time to “get going”. Gather people, start discussion. My advice? Plunge in. Do not be afraid of being wrong about a post. There are enough places if you want to be nervous about judgement. I feel this does not need to be one of them.
I think any standards will emerge over time and usage.
If you post something interesting to a similar group, feel free to post it here as well, as not all will be members of the same groups, and each group generates its own style over time.
It is not “restricted to” transdisciplinary and multidisciplinary discussion: What this means is you can start from where you are but there is leeway to allow a multitude of perspectives to work with.
If Physics is your thing, then by all means, Physics. Yet, should someone speaks of a sociological matter related to Physics, they have a voice. One may speak of biology and another responds with chemistry. Also, you can stay within the field you are comfortable: you do not have to relinguish the perspective you are familiar with.