#34146 - differential attention implementation for bert
Author: Chirayu-Tripathi
Pull request: yes

# What does this PR do?
Fixes https://github.com/huggingface/transformers/issues/34146
Implements differential attention for BERT

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Comments:
> Hey! Do you know if there were any official checkpoints trained with this attention? In general we would add a new model for DifferentialBert as it does not comput the same thing as eager, flash or sdpa

Hey @ArthurZucker,
Thanks for the review, but I am afraid they did not release the weights, I am hoping they would release it with time, or we might need to pre-train it.

Hey @ArthurZucker,
Sorry to bother you, I was wondering if we can still merge this, because I think the code can still be used to pre-train the model, or   does it require some major changes? 

Hey! Let's just keep this as is until we have released checkpoints! I would advise you to share your code on the hub this way people can use it! 🤗 https://huggingface.co/docs/transformers/v4.34.0/en/custom_models for more details!