Critical Discussion on the Planète Astronomie Forum
These links refer to a selection of my main contributions to this french discussion. They trace the development of my reflection on a possible new approach to spacetime and on the philosophical insights it may provide into the foundations of physics. From each of these posts, the contributions of the other participants can easily be found in the original discussion.
Discussion Method Time Aristotle and Inertia Causality Shuttle & Missile Relational Approach A Logical Contradiction in Relativity?Veiled Reality and Levels of Abstraction in Physics Where Exactly Does the Contradiction Lie?From Relative Simultaneity to InconsistencyResponse to Some Objections Concerning SimultaneityThe Distinction Betwen Absolute Simultaneity and Absolute TimeRelational Length ContractionRelational Approach and Ether TheoryUniversal Present and Proper TimesFrom Mathematical Formalism to Physical InterpretationAbsolute Simultaneity and the Speed of Light-1Speed of Light and Velocity CompositionFrom Einstein's Train to the Shuttle Missile ObjectionThe Relativity of Simultanity and the Existence of MissileIn the Light of the Principle of Non-ContradictionPrinciples of Logic in Response Externo-AIAbsolute Simultaneity Rests on the Very Existence of BeingLogigal Progession of the ArgumentationIntellectus and RatioThe Invariance of c and the Block Universe in Light of the Shuttle and Missile Objection-1The Invariance of c and the Block Universe in Light of the Shuttle and Missile Objection-2Positions of the Main ParticipantsAbsolute Simultaneity and the Speed of Light-2The Invariance of c and the Block Universe in Light of the Shuttle and Missile Objection-3To Avoid Dwellling Too Long on the Block UniverseTowards a Theory of the Universe: The Articulation Between Worldview, Mathematical Formalism, and ExperimentationTowards a Progressive Relationnal Understanding of Velocity CompositionDifference Between a Scientific Fact and a PostulateFrom Fundamental Concepts to Derived Concepts: A Necessary ClarificationOne-Way or Round-Trip Speed of Light: A Fondamental DistinctionA Little Argumentation Is Still NecessaryWhat the De Sitter Experiment Actually ShowsDe Sitter Experiment, Lorentz Ether, and Relationnal Approach to SpaceEther or a Relational Approach: What explanatory Scope?Mechanical Interaction and Relational Structure: A Necessary ClarificationUniversal Present, the Changing State of the Universe, and the Driving Principle of ChangePhysical Reality and Mathematical Formulation: A Distinction to PreserveCan Light Be Reduced to a Wave in an Ether?The Relationship between the “What is it?” and the “How?” Why going beyond Einstein’s interpretation also requires going beyond Lorentz’s interpretationOn the Relativity of Time and the Perpendicular Propagation of LightCan Clifford Geometry Provide a Foundation for Physical Concepts?Distance Contraction, Light Propagation, and the Limits of the Lorentzian InterpretationOn the Equivalence or Non-Equivalence of Inertial Frames of ReferenceDoes Motion Require a Presently Acting Cause?The Tidal Effect: Physical Proof That Not All Motions Are EquivalentThe Question of Inertia and Gravitation in an Ether TheoryTo externo: What Moves in Your Ether Theory? To externo: What Is a Celestial Body in Your Model?Externo's Conception of the Ether Put to the Test of the Equivalence Principle To Externo: Isn't Your Ether Gradually Evolving Toward the Idea of Space Quanta? Conceptual Foundations of a General Theory of the Universe Why Is a Possible Error in the Relativistic Framework So Difficult to Identify?Will You Stay Ahead of History, or Let It Catch Up with You…?Logical analysis of the shuttle and missile objectionReply to Dick — De Sitter and the Question of a Paradigm ShiftFizeau, De Sitter, and the Different Levels of AnalysisOn t′=f(t) and the Simultaneity of Two Distant Eventsde (t'=f(t))Variation in Clock Rates within the Framework of Absolute SimultaneityAtomic Clocks at Different Altitudes: What Do the Experiments Actually Show?Time, Motion, Duration, and the Mover PrincipleReply to Dick — Variation of Time or Variation of Durations?A Pause for Synthesis WorkPublication of a Synthesis Paper in a New Book
August–September 2026 — Writing a Synthesis Text and Publishing a New Book
This stage led to the publication of my book Conceptual Foundations of a Theory of the Universe on September 2, 2026. The contributions listed below were posted after its publication. They may offer clarifications and further developments that complement the book.
Availability of My Latest Book as an E-bookClarification on the One-Way Speed of LightTwo Propositions That Must Be DistinguishedThe Shuttle and Missile Objection: The Universal Present and Its Consequences for the Rest of the DebateIncompatibility Between the Invariance of the One-Way Speed of Light and Absolute SimultaneityTwo complementary variants of the train thought experimentThe Invariance of the One-Way Speed of Light: A Fundamental DifficultyFrom the Impossibility of Measurement to Logical ImpossibilityClarification of My Relational Approach to Length ContractionThe Sagnac Effect, Absolute Simultaneity, and the Relative Speed of LightThe Doppler Effect, Ether, and Spatial ConfigurationInterpreting Experiments: The Role of Conceptual FoundationsFair enough on the humor… but where do you think the error lies?Proof by Contradiction: Avoiding a Reversal of the ProblemOne-Way Speed of Light and the Relativity of SimultaneityClock Synchronization in Einstein’s PaperUnderstanding an Objection Before Rejecting ItInvariance in the Equations and Physical InvarianceImplied Metaphysical Consequence and Proof by ContradictionConceptual Foundations of Relativity: Two Approaches to Pursue in ParallelThe Approach to Causality in Relativity Is Flawed: It Must Be SupersededFrom the Existence of Bodies to Causality and the Driving Principle: The Steps of the ArgumentUniversal Present and Clock RatesClock Desynchronization and the Universal PresentExperimental Facts as a Basis for DiscussionDifferences in Clock Rates: Experimental Results, Interpretation, and a Shared PresentCausality as a guiding thread for understanding contemporary physicsA new thought experiment for Einstein?Spacelike Interval: Physical Existence and Access to InformationThe Interpretation of a Theory: A Question for ResearchRelativity of Simultaneity: Assigning Dates to Events and Physical ExistenceHypothetico-Deductive Reasoning Concerning the Missile’s ExistenceRelativity of simultaneity: merely a difference in time assignment, or also a physical reality?Instant and Duration: Do Not Confuse a Shared Present with Absolute TimeThe Cylinder Example: What Varies, the Representation or Physical Existence?Relativity of Simultaneity: Dating Convention or Physical Reality?Letter to Aurélien Barrau: Towards a New Conceptual Framework for Physics?Why Share My Letter to Aurélien Barrau in This Discussion?Asserting Is Not ProvingClock Comparison and Examination of My ObjectionAre My Explanation and My Objection Understood?Why My Objection May Go Unnoticed Within the Relativistic FrameworkEinstein’s Train Thought Experiment and Perspective EffectRelativity in Question: Foundations, Levels of Analysis, and the Scope of Physics