Sankar Hajra

Sankar Hajra
Born	1946 (age 79–80) Rajagram, Hooghly district, West Bengal, India
Residence	Calcutta (Kolkata), India
Nationality	Indian
Known for	Classical electrodynamic interpretations of relativity
Scientific career
Fields	Physics
Institutions	Indian Physical Society, Kolkata; Indian Association for the Cultivation of Science, Kolkata

Sankar Hajra (born 1946) is an Indian researcher in theoretical physics based in Calcutta (Kolkata), West Bengal. Working outside mainstream academia, he is known for a research programme that seeks to reinterpret the effects predicted by the special and general theories of relativity as consequences of classical electrodynamics, drawing on the field equations of James Clerk Maxwell together with Newtonian mechanics. His central contention is that electric charges, electromagnetic fields and light are real physical objects carrying momentum and energy, that they are therefore subject to gravitation, and that they are carried along with the Earth near its surface — a classical premise from which he argues the relativistic reformulation of space and time becomes unnecessary.

Biography

Hajra was born in 1946 in the village of Rajagram, in the Hooghly district of West Bengal, India. His father, Ratimohan Hajra, was a primary school teacher noted for his proficiency in mathematics. Hajra received his early schooling at Bajua High School, where he studied mathematics under H. C. Ghosh. He went on to graduate from Presidency College, Calcutta, a college of long standing repute in India.

After completing his education, Hajra joined the Reserve Bank of India in Calcutta, where he worked until his retirement in 2005, pursuing physics research alongside and then full-time after his banking career. His interest in the foundations of relativity was encouraged by Debabrata Ghosh, a Calcutta-based critic of relativity theory, under whom he studied the subject. Hajra has published under the affiliations of the Indian Physical Society, Kolkata, and the Indian Association for the Cultivation of Science, Kolkata.

He has presented his work internationally, including at the Physical Interpretations of Relativity Theory (PIRT) conference series in London, where he presented "A Critical Analysis of Special Relativity" in 2000.

Scientific contributions

Hajra's work concerns the foundations of the special and general theories of relativity. He contends that the phenomena usually attributed to relativity can instead be derived from classical physics, treating them as consequences of Maxwell's electrodynamics combined with Newtonian mechanics rather than as evidence for the relativistic reformulation of space and time. In this programme he has attempted to obtain the electrodynamic relations used by special relativity — including forms of the Lorentz transformation equations — directly from the Maxwell field equations, arguing that these relations were already classical results, several of them available in the work of Oliver Heaviside in the 1880s, before Einstein's 1905 paper.

Electromagnetic entities as physical objects

The premise underlying most of Hajra's papers is that electric charges, electric and magnetic fields and electromagnetic radiation possess measurable momentum and energy, and so are physical entities in the same sense as material bodies. If that is granted, he argues, then those entities must be subject to gravitation exactly as matter is, and near the Earth's surface they must be dragged along by the Earth's gravitational field. From this he derives what he regards as a straightforward classical account of the null results of the Michelson–Morley type of experiment: no ether wind is detected because the electromagnetic fields in the apparatus are carried with the Earth, not because space and time must be reformulated. In his 2012 paper in the Journal of Modern Physics he set out this position at length, arguing that classical electrodynamics with the Heaviside mass formula, together with gravitational action on electromagnetic entities, reproduces the transverse Doppler effect, the increase of decay lifetimes of moving unstable particles, the bending of light and other results usually cited as relativistic confirmations.

Relativistic precessions

In "Classical interpretations of relativistic precessions" (Chinese Physics B, 2014) Hajra argued that the precession of the perihelion of Mercury, the Thomas precession, and the de Sitter (geodetic) and Lense–Thirring precessions measured by the Gravity Probe B mission can each be obtained from classical physics without appeal to curved spacetime. He treated these as dynamical consequences of gravitating fields acting on electromagnetic and rotating bodies, and returned to the subject in later work on relativistic precessions and classical electrodynamics.

Coriolis rather than Sagnac

In a paper published in Pramana – Journal of Physics (2016) he argued, from considerations of classical electrodynamics, that the effect measured in ring-laser and circuital-light-beam experiments on the rotating Earth — such as those of Michelson–Gale and of Bilger and collaborators — should be understood as a Coriolis effect arising from the Earth's rotation acting on light carried with the Earth, rather than as a Sagnac effect requiring a relativistic reading.

Later work

In "An Attempt of Linking Maxwell with Newton to Study Electrodynamic Phenomena" (Bulgarian Journal of Physics, 2022) Hajra restated the programme in two parts: first that all the electrodynamic equations employed by special relativity are classical in origin, and second that electromagnetic fields, light and charges, being real physical objects, are subject to gravitation and carried with the Earth in its near vicinity. He has also circulated a preprint proposing a simple terrestrial experiment to test the speed of gravity, and thereby the general theory of relativity.

Hajra's articles have appeared in journals and proceedings including Pramana, Chinese Physics B, Journal of Modern Physics, the Bulgarian Journal of Physics, the Journal of Gravitational Physics, Galilean Electrodynamics, and the Physical Interpretations of Relativity Theory (PIRT) conference series.

CNPS talks

He has presented in the CNPS online seminar series, in sessions hosted by Ian Cowan:

• "Collapse of GRT" (3 August 2025)
• "Collapse of Special Theory of Relativity" (19 July 2025)

Abstracts

• 2011 - "The Cross Radial Force" (Read in full)
• 2010 - "Electric charge, Light, Gravitation and Old Physics"
• 2010 - "Some Experiments that Shook the World"
• 2008 - "Large-Charge Electrodynamics and SRT"
• 2007 - "Collapse of GRT: EM Interactions with Gravity Derived from Maxwell and Newton"
• 2006 - "Collapse of SRT 2: Earth Carries Along Electric and Magnetic Fields"
• 2005 - "Collapse of SRT 1: Derivation of Electrodynamic Equations from the Maxwell Field Equations"

Works

• "An Attempt of Linking Maxwell with Newton to Study Electrodynamic Phenomena", Bulgarian Journal of Physics 49 (2022), pp. 145–162.
• "Spinning Earth and its Coriolis effect on the circuital light beams: Verification of the special relativity theory", Pramana – Journal of Physics 87:71 (2016).
• "Classical interpretations of relativistic precessions", Chinese Physics B 23, 040402 (2014).
• "Classical Interpretations of Relativistic Phenomena", Journal of Modern Physics 3, no. 2 (2012), 13 pp.
• "A Study on the Interaction of Gravitating Fields with Electromagnetic Entities", Journal of Gravitational Physics 2, no. 2 (2008), pp. 7–22.
• "Collapse of GRT: EM Interaction with Gravity derived from Maxwell and Newton", Galilean Electrodynamics 18, no. 4 (2007), pp. 73–76.
• "Collapse of SRT 2: Earth carries along electric and magnetic fields" (2006).
• (with Antina Ghosh) "Collapse of SRT 1: Derivation of electrodynamic equations from the Maxwell field equations", Galilean Electrodynamics 16, no. 4 (2005).
• "A Critical Analysis of Special Relativity", Proceedings of Physical Interpretations of Relativity Theory, London (2000).

Media

• 2010 - Maxwell, Maxwell and Maxwell: Collapse of Relativity, Special & General (Video Lecture)

External links

• "Spinning Earth and its Coriolis effect on the circuital light beams" — Pramana – Journal of Physics 87:71 (2016)
• "Classical interpretations of relativistic precessions" — Chinese Physics B 23, 040402 (2014)
• "An Attempt of Linking Maxwell with Newton to Study Electrodynamic Phenomena" — Bulgarian Journal of Physics 49 (2022)
• Sankar Hajra at ResearchGate