Jacobsen's main areas of research include
Sāṃkhya,
Yoga, Pilgrimage in South Asia, and South Asian religions and migration.
He is the founding editor and editor-in-chief of the six volume Brill's Encyclopedia of Hinduism (2009–2015) and editor-in-chief of the Brill's Encyclopedia of Hinduism Online.
He is the author or editor of more than 30 books, in Norwegian and English.
Writings
Selected Writings in English include:
1999 Prakṛti in Sāṃkhya-Yoga: Material Principle, Religious Experience, Ethical Implications. New York: Peter Lang
2004 South Asians in the diaspora: histories and religious traditions. (with P. Pratap Kumar). Leiden: Brill.
2005 Theory and Practice of Yoga: Essays in Honour of Gerald James Larson. Leiden: Brill.[4]
2011 Sikhs in Europe: Migration, Identity and Transnational Practices. (with Kristina Myrvold). Farnham: Ashgate.
2011 Brill's Encyclopedia of Hinduism. Volume Three: Society, Religious Professionals, Religious Communities, Philosophies. Leiden: Brill.
2012 Yoga Powers: Extraordinary Capacities Attained Through Meditation and Concentration. Leiden: Brill.
2012 Brill's Encyclopedia of Hinduism. Volume Four. Historical Perspectives, Poets/Teachers/Saints, Relation to Other Religions and Traditions, Hinduism and Contemporary Issues. Leiden: Brill.
2012 Sikhs Across Borders. (with Kristina Myrvold). London: Bloomsbury.
2013 Pilgrimage in the Hindu Tradition: Salvific Space. Abingdon: Routledge.
2013 Brill's Encyclopedia of Hinduism. Volume Five: Symbolism, Diaspora, Modern Groups and Teachers. Leiden: Brill.
2015 Brill's Encyclopedia of Hinduism. Volume Six: Indices. Leiden: Brill.
2015 Objects of Worship in South Asian Religions (co-edited with Mikael Aktor og Kristina Myrvold). Abingdon: Routledge.[5]
2015 Young Sikhs in a Global World. (with Kristina Myrvold). Farnham: Ashgate.[6]
2016 Routledge Handbook of Contemporary India. Abingdon: Routledge.[7]