• Anti-Einstein Sentiment Surfaces Again - A review of "The Incorrigible Plagiarist" which finds fault with its premises and its conclusions.
• The Axiomatization of Physics - Step 1: A Derivation of the Lorentz Transformation - The fundamental equations of special relativity are derived with only high school algebra and toy universes consisting of moving rulers. [PDF]
• Breaking in the 4-Vectors: the Four-Dimensional Movement in Gravitation, 1905–1910 - The four-dimensional language of physics originated with Poincaré, Minkowski, and Sommerfeld in their study of the geometric and symbolic expressions of gravitational action. 57 pages. [PDF]
• Derivation of the Lorentz Transformation - This derivation assumes linearity and the group property of the Lorentz transformations and is compactly written in matrix form. For those not familiar with matrix notation, it is also written without matrices. [PDF]
• Deriving Relativistic Momentum and Energy - Expressions for momentum and energy of a relativistic particle may be derived from the composition law for velocities along one spatial dimension.
• Deriving Relativistic Momentum and Energy. II. - The usual relativistic expressions for momentum and kinetic energy are generalized from the one-dimensional to the three-dimensional case.
• Dual origin of E=mc² - Another article on the arXiv server saying that the discovery of the mass-energy relation E=mc² cannot be properly attributed to Albert Einstein.
• Einstein, Nordström and the Early Demise of Scalar, Lorentz Covariant Theories of Gravitation - Conventional thinking says that all Lorentz covariant gravitation theories are unacceptable. 74 pages. [PDF]
• Einstein's Time - A discussion of the differences in perspective between Einstein and Poincaré by Peter Galison, from the American Institute of Physics.
• E=mc² - An article from the Wikipedia encyclopedia.
• E=mc² before Einstein - According to University of Perugia historian of mathematics Umberto Bartocci, Olinto De Pretto published the famous formula E=mc² two years before Albert Einstein in a paper titled "Ipotesi dell’etere nella vita dell’universo" (Hypothesis of the Essence of the Universe).
• E=mc² is Not Einstein's Discovery - The mathematician Robert A. Herrmann presents a brief history on the mass-energy equation E=mc² to challenge the myth that Einstein was the first to understand that radiant energy has mass. [PDF]
• E=mc² was an Italian's Idea - The University of Perugia historian of mathematics Umberto Bartocci claims that a Swiss Italian named Michele Besso alerted Einstein to the writings of Olinto De Pretto who then published Pretto's mass-energy equation without giving credit.
• Generalized Relativistic Velocity Addition with Spacetime Algebra - The general problem of relativistic addition of velocities – and the successive application of noncollinear Lorentz boosts – is addressed. [PDF]
• Geometric Algebra for Physicists - This is chapter 1 of a book by Chris Doran and Anthony Lasenby on geometric algebra, which is the natural mathematics of spacetime, electromagnetism and quantum theory. [PDF]
• Henri Poincaré: A Decisive Contribution to Special Relativity - Henri Poincaré set up all the basic concepts of special relativity several years before Einstein published On the Electrodynamics of Moving Bodies (Annalen der Physik vol XVII 1905 p. 891-921). This is the short version of the story.
• Henri Poincaré and Relativity Theory - Who created the theory of relativity? This reference identifies the substantial contributions made to relativity theory by the mathematician Henri Poincaré. 254 pages. [PDF]
• How Did Einstein Discover Special Relativity? - Dr. John Stachel speculates on how Einstein arrived at SRT. Dr. Stachel is Professor of Physics Emeritus and Director of the Center of Einstein Studies at Boston University.
• How Do You Add Velocities in Special Relativity? - Here is the formula for adding velocities in special relativity when motion occurs in a single direction.
• Imaginary in all Directions - There is a preferred algebra of quaternions and complex numbers that is ideally suited to express the equations of special relativity and classical electrodynamics. [PDF]
• Lorentz Contraction and Accelerated Systems - Lorentz contraction in systems undergoing constant proper acceleration is proven to be completely self-consistent in the context of special relativity. [PDF]
• Lorentz Transformation - In physics, the Lorentz transformation is a set of equations that converts back and forth between two different observers' measurements of space and time.
• Lost in Einstein's Shadow - American Scientist magazine article describes the people whose work paved the way for the special theory of relativity. (March, 2006)
• Michelson, FitzGerald and Lorentz: the Origins of Relativity Revisited - It is argued that the beginning of relativity theory occurred in early 1889, when G. F. FitzGerald wrote a letter to Oliver Heaviside concerning a result the latter had just obtained from Maxwell's equations. [PDF]
• Minkowski, Mathematicians, and the Mathematical Theory of Relativity - Minkowski claimed scientific priority for a great, new, geometric theory of relativity at the Cologne lecture of 1908, based largely on the work of Poincaré. Poincaré was purposely excluded from the meeting. 42 pages. [PDF]
• The Mystery of the Einstein–Poincaré Connection - This essay discusses attempts that have been made to explain the striking similarities between two relativity theories propounded in 1905 by Albert Einstein and Henri Poincare without any mutual reference. [PDF]
• A Note on Relativity Before Einstein - The first presentation of the Lorentz transformations, including the crucial time dilation, belongs to Larmor (c. 1897). [PDF]
• Nothing but Relativity - There are many ways to derive the Lorentz transformation without invoking Einstein's constancy of light postulate. The path preferred in this paper restates a simple, established approach. [PDF]
• One More Derivation of the Lorentz Transformation - The theory of relativity is constructed from four general group-theoretical assumptions on the structure of space-time: These are homogeneity, isotropy, group structure and a causality condition. [PDF]
• The Origins of Length Contraction: I. The Fitzgerald-Lorentz Deformation - One of the widespread confusions concerning the history of the 1887 Michelson-Morley experiment has to do with the initial explanation of this celebrated null result due independently to FitzGerald and Lorentz. [PDF]
• Poincaré and the Special Theory of Relativity - It took many great minds to finally attain the point of view that is now called ‘the special theory of relativity’. [PDF]
• Poincaré’s Relativistic Physics: Its Origins and Nature - An analysis of Poincaré’s development of the principle of relativity after 1895 and of Poincaré’s major paper of 1905, “On the Dynamics of the Electron.” [pay to view]
• Quaternions in University-Level Physics Considering Special Relativity - The quaternions are an expansion of complex numbers and show close relations to numerous physically fundamental concepts (e.g. Pauli Matrices). [PDF]
• Reciprocity Principle and the Lorentz Transformations - V. Berzi and V. Gorini claim to have proved the reciprocity relation for the relative motion of two inertial frames of reference. Copied for the purpose of criticism from the Journal of Mathematical Physics, Volume 10, Number 8, August 1969.
• Relativistic Contraction - Relativists consider it a very important exercise to have students decide how to measure the length of a rapidly moving object.
• Relativistic Force Transformation - Formulas relating one and the same force in two inertial frames of reference are derived directly from the Lorentz transformation of space and time coordinates. [PDF]
• Relativistic Kinematics - This is how special relativity is taught by Dr. David Morin at Harvard University. 72 pages. [PDF]
• Relativity in its Historical Context - The discovery of special relativity was inevitable, given the momentous discoveries that preceded it.
• Relativity Priority Dispute - Is it true that Albert Einstein was highly indebted to others for much of special and general relativity and never acknowledged their valuable contributions?
• Sagnac Effect, Twin Paradox and Space-Time Topology - When viewed with an alternative synchronization convention, the Sagnac effect on a rotating disk is purely topological and the rim of the disk is essentially an inertial system. 31 pages. [PDF]
• Santa at Nearly the Speed of Light - An estimate of the speed and distances covered by Santa Claus on Christmas night. The physics is unassailable. The article is hosted on the Fermi National Accelerator Laboratory website.
• Space Measurements on a Rotating Platform - The age-old puzzling problem of Lorentz contraction on a rotating platform, i.e., Ehrenfest's paradox, is explained in its proper mathematical context. 14 pages. [PDF]
• Special Relativity - A unit for an online relativity textbook explaining special relativistic mathematical physics.
• Special Relativity - A brief overview of the theory of special relativity, and how it pertains to particles at SLAC (Stanford Linear Accelerator)
• Special Relativity - This is chapter two of Christoph Schiller's 1000 page walk through the whole of physics, from classical mechanics to relativity, electrodynamics, thermodynamics, quantum theory, nuclear physics and unification. 61 pages. [PDF]
• Special Relativity and Maxwell Equations - A self-contained summary of the theory of special relativity is given, which provides the frame for classical electrodynamics. 26 pages. [PDF]
• Special Relativity Article - From the encyclopedia Wikipedia.
• The Structure of Space-Time Transformations - This theorem by H. J. Borchers and G. C. Hegerfeldt proves that the constancy of light velocity alone implies the Lorentz group (up to dilatations).
• Student Understanding of Time in Special Relativity - A report on the ineffectiveness of standard university instruction in Einstein's concept of time by Rachel E. Scherr, Peter S. Shaffer, and Stamatis Vokos. 22 pages. [PDF]
• Synchronization Gauges and the Principles of Special Relativity - Synchronization functions set the mathematical clocks represented by the Lorentz transformation and resetting these clocks mathematically only produces a theory equivalent to special relativity in predicting empirical facts. 57 pages. [PDF]
• Time Dilation - The gamma factor and time dilation can be derived using a very simple clock.
• Time Travel - Prominent physicists discuss what it would take to make time travel possible. A Nova transcript. PBS Airdate: October 12, 1999.
• The Twin Paradox in a Spatially Closed and Bounded Universe - Spatially compact spacetimes break global Lorentz invariance and define absolute inertial frames of reference.
• University Lectures on Special Relativity - Lecture notes on Special Relativity, prepared by J. D. Cresser, Department of Physics, Macquarie University. 44 pages. [PDF]
• Who Invented Relativity? - By 1892, Fitzgerald, Larmor and Lorentz had all arrived at the Lorentz transformations including all the peculiar "time dilation" and "length contraction" effects.
• Why No 'New Einstein'? - Followers of large well-supported research programs have lots of powerful senior scientists to promote their careers. People with the uncanny ability to ask new questions or recognize unexamined assumptions are often underappreciated. [PDF]

General Relativity Directory