Entanglement setup that shouldn't allow for the transmission of info

[entropy1]

Suppose we produce a polarisation-entangled photon pair $A_1$ and $A_2$. Then we entangle another pair $B_1$ and $B_2$.

Now suppose that these photons will not interact with anything, sending $A_1$ and $B_1$ to Alice and $A_2$ and $B_2$ to Bob.

Alice measures the polarisations of the pair of photons she received. Bob however doesn't measure them, but either entangles them correlative or anti-correlative.

I don't know a lot of aspects of this setup, but I ask: what makes transmission of information impossible?

 

[vanhees71]

Search for "entanglement swapping" in these forums. We had a huge thread about it, discussing all aspects about "transmission of information".

 

[DrChinese]

Alice measures the polarisations of the pair of photons she received. Bob however doesn't measure them, but either entangles them correlative or anti-correlative.

I don't know a lot of aspects of this setup, but I ask: what makes transmission of information impossible?

The key word in your setup is the bolded "or". This is not something Bob can control when Bob performs an entanglement swap. A successful swap places the 2 photons in a random unknown state. (A random state obviously doesn't allow for much information to be present.)