Sobczyk's simplicial calculus does not have a proper foundation
The pseudoscalars in Garret Sobczyk's paper \emph{Simplicial Calculus with Geometric Algebra} are not well defined. Therefore his calculus does not have a proper foundation.
math.GM↗
arXiv subjects
Alan Macdonald
Publications and source records attributed to Alan Macdonald.
Comment on "The Cosmic Time in Terms of the Redshift", by Carmeli et al
The time-redshift relation of Carmeli et al. differs from that of the standard flat LambdaCDM model by more than 500 million years for 1 < z < 4.5.
gr-qc↗
Still the "World's Fastest Derivation of the Lorentz Transformation"
Rothenstein's claim of a ``faster'' derivation of the Lorentz transformation is not correct.
physics.class-ph↗
Entanglement, joint measurement, and state reduction
Entanglement is perhaps the most important new feature of the quantum world. It is expressed in quantum theory by the joint measurement formula. We prove the formula for self-adjoint observables from a plausible assumption, which for spacelike separated measurements is an expression of relativistic causality. State reduction is simply a way to express the JMF after one measurement has been made, and its result known.
quant-ph↗
The fundamental theorem of geometric calculus via a generalized Riemann integral
Using recent advances in integration theory, we give a proof of the fundamental theorem of geometric calculus. We assume only that the tangential derivative $\nabla_VF$ exists and is Lebesgue integrable. We also give sufficient conditions that $\nabla_VF$ exists.
math.DG↗