Changing all non trivial operations that use broadcasting with einsum where possible

[wiederm]

Pull Request Summary

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Key changes

Notable points that this PR has either accomplished or will accomplish.

• Change 1

Questions

• Question 1

Associated Issue(s)

• Issue 1

Pull Request Checklist

• Issue(s) raised/addressed and linked
• Includes appropriate unit test(s)
• Appropriate docstring(s) added/updated
• Appropriate .rst doc file(s) added/updated
• PR is ready for review

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.43%. Comparing base (c1430f2) to head (64e4cfa).

Additional details and impacted files