Is there any real association between different sites (except Association Bonus)?

Question

Stack Exchange has grown to consist of over 130 sites, that discuss a variety of subjects. We still call ourselves a single network. Apart from the fact that the basic functioning is the same, there isn't much 'association' between the sites (that I know of, except for Association Bonus of 100).

There are a lot of links between the subjects discussed on the various sites.

For example, there are various physics questions that require a higher level of mathematical understanding. Yes, these questions may be off-topic on the maths site, but a person answering it on the physics site should receive some rep on his math account also. Someone answering a question tagged 'physics' on the maths could receive reputation on his physics account also.

Similarly, someone answering questions on the web applications site could also receive reputation on his main SE account. This will help since there are many computer-related sites (main, programmers, stackoverflow, code golf, etc.), with only slight differences in accepted questions. There should be an option of posting a question on 2 or even 3 sites, if it fits the criteria for all of them.

I currently know that only that only the association bonus links the sites, and reputation, badges, moderation, etc. are all kept separate. Please correct me if I am wrong.

Will this lead to over-complication, or is it a good idea? It is only an 'idea' that I got, how it could be implemented is completely upto the community.

Answer 1

First off, there are more, limited ways, where sites do have some interactions. The fact that one can have multiple accounts linked together is one. Another is the (limited) ability to migrate questions between sites.

There should be an option of posting a question on 2 or even 3 sites, if it fits the criteria for all of them

I think this will indeed both over-complicate and confuse matters (never mind that the current implementation doesn't lend itself to it - if we think it is worth it, we would manage a change).

It is also not needed - though there is some overlap between certain sets of sites, that's all it is - some overlap.

We have and still maintain that if a question conceptually better belongs on one site in a set, it should be asked there.