What is Research gate?

From the platforms website

[Their] mission is to connect researchers and make it easy for them to share and access scientific output, knowledge, and expertise. On ResearchGate they find what they need to advance their research.

Some of the CH(A)T academics are on Research gate. For finding them you can follow for example the ‘topics’: Sociocultural Theory of Learning; Activity Theory. Also you can search and follow people.