can you tell me the differences between libertarianism and objectivism
I am not authority on the subject, but google the terms, you will find some articles explaining the differences.
Clasically, philosophy has 5 branches: metaphysics, epistemology, ethics, politics, and esthetics.
Objectivism is a complete philosophy, with published material in all 5 branches.
Libertarianism is synonymous with the politics of Objectivism.