arXiv subjects

Herman Telkamp

Publications and source records attributed to Herman Telkamp.

8 recordsLinked to original sources

arXiv2019

Observing evolution from steady state

The time-translation symmetry of the conformal FLRW frame $\bar{g}=a^{-2}g$ allows reinterpretation of cosmological observation in the static space of a stationary universe, where constant matter density $\bar{\rho}_{\textrm{m}}=\rho_{\textrm{m0}}$ induces constant curvature $R_{0}^{-2}$. A hyperbolic de Sitter solution arises from equipartition of the kinetic energy of recessional and peculiar components of the gravitational field, corresponding to a total density $24R_{0}^{-2}$ of twice the scalar curvature. This predicts a matter density $\Omega_{\textrm{m}}=\frac{1}{24}$, or a Hubble constant $h=\sqrt{24\rho_{\textrm{m0}}}\approx0.72$, in agreement with distance-ladder estimates. Projecting the equilibrium state onto the $\Lambda\textrm{CDM}$ model returns $\hat{h}=\frac{4}{3}\sqrt{12\rho_{\textrm{m0}}}\approx0.68$ and exact densities $\hat{\Omega}_{\textrm{m}}=1-\hat{\Omega}_{\Lambda}=[\textrm{sinh}(\frac{4}{3}\textrm{asinh}(1))^{2}+1]^{-1}=0.3179...$, within confidence limits of Planck 2018 results.

physics.gen-ph↗

arXiv2018

Mass in cosmological perspective

We consider the total nonlocal energy associated with a particle at rest in the Hubble flow, i.e., the relational energy between this particle and all connected particles within the causal horizon. The particle, even while at rest, partakes in relative recessional and peculiar motion of connected particles in 3 dimensions. A geometrical argument due to Berkeley suggests that the nonlocal mass of recessional energy associated with the particle is 3 times its Newtonian mass. It follows that nonlocal recessional and peculiar energy of the Universe are equal, and match Misner-Sharp energy within the apparent horizon. Contributions of recessional and peculiar nonlocal energy are thus shown to generate a 6 times higher level of matter energy than expected from the Newtonian mass. Accordingly, the nonlocal energy density of baryons is expected to be 6 times the standard local energy density of baryons, i.e., $\Omega_{\textrm{b,eff}}=6\Omega_{\textrm{b}}$. At $\Omega_{\textrm{b}}\sim0.0484\pm0.0017$ (Planck 2015 results) this predicts a nonlocal baryon energy density $\Omega_{\textrm{b,eff}}\sim0.290\pm0.010$, in agreement with observed matter density $\Omega_{\textrm{m}}\sim0.308\pm0.012$. The effect of nonlocal mass on solar system and galactic scales is considered.

gr-qc↗

arXiv2017

Cosmology from conservation of global energy

It is argued that many of the problems and ambiguities of standard cosmology derive from a single one: violation of conservation of energy in the standard paradigm. Standard cosmology satisfies conservation of local energy, however disregards the inherent global aspect of energy. We therefore explore conservation of the quasi-local Misner-Sharp energy within the causal horizon, which, as we argue, is necessarily an apparent horizon. Misner-Sharp energy assumes the presence of arbitrary mass-energy. Its conservation, however, yields "empty" de Sitter (open, flat, closed) as single cosmological solution, where Misner-Sharp total energy acts as cosmological constant and where the source of curvature energy is unidentified. It is argued that de Sitter is only apparently empty of matter. That is, total matter energy scales as curvature energy in open de Sitter, which causes evolution of the cosmic potential and induces gravitational time dilation. Curvature of time accounts completely for the extrinsic curvature, i.e., renders open de Sitter spatially flat. This explains the well known, surprising, spatial flatness of Misner-Sharp energy, even if extrinsic curvature is non-zero. The general relativistic derivation from Misner-Sharp energy is confirmed by a Machian equation of recessional and peculiar energy, which explicitly assumes the presence of matter. This relational model enhances interpretation. Time-dilated open de Sitter is spatially flat, dynamically close to $\Lambda$CDM, and is shown to be without the conceptual problems of concordance cosmology.

physics.gen-ph↗

arXiv2016

Machian derivation of the Friedmann equation

Despite all fundamental objections against Newtonian concepts in cosmology, the Friedmann equation derives from these in an astoundingly simple way through application of the shell theorem and conservation of Newtonian energy in an infinite universe. However, Friedmann universes in general posses a finite gravitational horizon, as a result of which the application of the shell theorem fails and the Newtonian derivation collapses. We show that in the presence of a gravitational horizon the Friedmann equation can be derived from a Machian definition of kinetic energy, without invoking the shell theorem. Whereas in the Newtonian case total energy translates to curvature energy density, in the Machian case total energy takes on different identities, depending on the evolution of the horizon; we show that in the de Sitter universe Machian total energy density is constant, i.e. appears as cosmological constant.

gr-qc↗

arXiv2015

{\Lambda}CDM cosmology from visible matter only

We discuss physical interpretation of {\Lambda}CDM cosmology from a Machian model of the universe containing nothing but visible matter (ordinary matter, radiation). The Friedmann equation can be derived from a Machian definition of energy, whereby both kinetic and potential energy of a particle are related to all cosmic matter-energy within the particle's gravitational horizon. The distance to this horizon thus appears as a parameter in all forms of matter-energy density. From conservation of Machian energy it follows that all different types of matter-energy are uniformly characterized by \rho\propto 1/a, i.e., by a constant deceleration q=-1/2. This coincides with relative densities \varOmega_{m}=1/3 and \Omega_{\Lambda}=2/3 of {\Lambda}CDM. Thus the Machian cosmological model matches present relative densities of {\Lambda}CDM, without invoking dark components.

gr-qc↗

arXiv2014

On the material origin of the cosmological constant

We consider a possible connection between matter and cosmological constant $Λ$ via the Newtonian cosmic potential of the matter within the expanding particle horizon. Consistent with GR, an increasing potential may drive the metric expansion of space. Cosmic recession of mass must, in turn, affect the potential in an opposite sense. Independent of this, several considerations point at $-\tfrac{1}{2}c^{2}$ as the representation of the background potential in the various GR metrics. This suggests that the cosmic potential, while subject to the expansion of space, always yields a constant background potential $-\tfrac{1}{2}c^{2}$. Analysis of this 'redshift' of the cosmic potential yields for perfect fluids the exact same solutions of the scale factor as the standard Friedmann equations, including an accelerating de Sitter universe. Though counter intuitive at first sight, gravity may drive cosmic acceleration.

physics.gen-ph↗

arXiv2014

A relational approach to the Mach-Einstein question

Mach's principle is incompatible with general relativity (GR), it has not condensed into an established theory and suffers from inconsistencies. Yet, the problem is that Mach's principle is a consequence of Berkeley's notions, which are as good as irrefutable for their ontological nature. Moreover, the observed coincidence of the "preferred inertial frame" and the frame attached to the "fixed stars" is essentially Machian, while this coincidence is anomalous to both GR and Newtonian physics. Another issue is that GR needs dark energy to explain the accelerating expansion of the universe, while acceleration of receding masses is inherent to the Machian principle. So GR and Mach's principle question each other, while neither one can be falsified easily. This suggest that both are valid in their particular domain. A relational theory may reconcile the two, since it can cover both.

gr-qc↗

arXiv2012

A Relational Concept of Machian Relativity

Mach's principle fits into the wider "relational principle", advocating that not only inertia, but also space and time emerge from the interaction of matter. Concepts of a Machian/relational theory are proposed, where inertia and energy are defined as mutual properties between pairs of objects. Due to Berkeley, only radial motion represents kinetic energy between (point) masses, which is the basis of anisotropic inertia, which in turn underlies the relational principle. The Newtonian definition of potential energy is considered a model for Machian inertia, leading to a frame independent definition of Machian kinetic energy, which comprises of the Newtonian terms (relative to the "fixed stars") and small anisotropic Machian energy terms between objects. The latter account for relativistic trajectories, such as the anomalous perihelion precession and Lense-Thirring frame dragging. However, relativistic effects of remote observation (e.g. time dilation) demand an isotropic model. A relational spacetime metric is derived, which provides an isotropic coordinate transform of the anisotropic Machian model, yielding a relational model which matches GR expressions for relativistic trajectories and effects of remote observation. Therefore, the experimental verification of GR in these cases holds automatically for the relational model. The relational model fits the relational principle (including Mach's principle) and it is argued that it includes GR as a special case. The relational metric provides both contraction and (unbound) expansion as a function of relative potential, i.e. without invoking dark energy.

physics.hist-ph↗