Spacetime Fundamentals Intelligibly (Re)learnt

DIRECTED BOTH AT PHYSICISTS CONVENTIONALLY 'VERSED' IN SPACETIME THEORY AS WELL AS AT KEEN SCHOOL-MATHS NOVICES, this book unravels special relativity in one spatial dimension. Avoiding misnomers such as 'proper' (own-) and confusing presentisms such as 'length contraction', Parts I and II show how time dissimultaneities and spacetime sameness lead to a boundary speed identifiable without postulation as the speed of light. As also earlier detailed in a series of European Journal of Physics papers, Part III discards the populist 'relativistic mass' idea aptly branded 'a pedagogical virus' by Lev Okun, and uses two underrated equations to properly clarify Newton's reaction equals action principle traditionally misrepresented and misinterpreted in relativity. Part IV-SPHERICAL GEOMETRY SURPRISES offers innovative visual insights into relativistic acceleration. Tracing a rocket's scaled 'own-time', a seemingly unknown spherical 'HEMIX' spiral's colatitude reflects changing scaled velocity-a spacetime 'intrinsic world-line' curiously reminiscent of marine navigation's 1537 loxodrome. As expounded in 2016 in the Results in Physics journal, Part V-AN OCCAM STEEPLECHASE and Part VI-THE RELATIVITY CURATE'S EGG explore fixed-thrust rockets' time dispersals and retro-separations and oddly hitherto ignored radar formulae which bypass highly convoluted literature approaches and directly sort out the 'rigor mortis' ('rigid motion') acceleration issue shown to be epitomised by a simple 'hand-held fan' real-values metric 'own-surface'. Part VII-ROLLER COASTING SPACETIME solves the 'Bell's spaceships' enigma: How does a co-accelerating medium between twin rockets 'expand'? The hemix spiral generates the helicoidal solution-a real metric 'HEMICOID' own-surface hosting hemices which chart increment own-times. The hemices are crossed by expanding non-inertial own-length helices which are extrinsically validated by 'cosmographic' overlappings of shared velocity cylinders and 'distances helicoid' boundaries. Basic geometry intrinsically corroborates the apparently unprecedented hemicoid surface which, as shown in a sequel 2017 Results in Physics paper, itself uniquely emerges independently of relativity theory. Successive radar trajectories not only surf 'horizon' hemices as required, they also traverse each shared own-time medium expansion helix at identical angles and geodesic curvatures-regardless of their original rear rocket emission times. A casualty where an accelerating medium is concerned, widely sacrosanct Minkowski spacetime is plainly exposed as overgeneralised even in special relativity. Equivocating reactions of physicists and institutions unsettled by such a conclusion are chronicled in the book's EPILOGUE-Minkowski spacetime's 'post-truths'.