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General relativity is a fully conservative theory, but there exist other possible metric theories of gravity. We consider non-conservative ones with a parameterized post-Newtonian (PPN) parameter, $zeta_2$. A non-zero $zeta_2$ induces a self-acceleration for the center of mass of an eccentric binary pulsar system, which contributes to the second time derivative of the pulsar spin frequency, $ddot{ u}$. In our work, using the method in Will (1992), we provide an improved analysis with four well-timed, carefully-chosen binary pulsars. In addition, we extend Wills method and derive $zeta_2$s effect on the third time derivative of the spin frequency, $dddot{ u}$. For PSR B1913+16, the constraint from $dddot{ u}$ is even tighter than that from $ddot{ u}$. We combine multiple pulsars with Bayesian inference, and obtain an upper limit, $left|zeta_{2}right|<1.3times10^{-5}$ at 95% confidence level, assuming a flat prior in $log_{10} left| zeta_{2}right|$. It improves the existing bound by a factor of three. Moreover, we propose an analytical timing formalism for $zeta_2$. Our simulated times of arrival with simplified assumptions show binary pulsars capability in limiting $zeta_{2}$, and useful clues are extracted for real data analysis in future. In particular, we discover that for PSRs B1913+16 and J0737$-$3039A, $dddot{ u}$ can yield more constraining limits than $ddot{ u}$.
Gravitational waves emitted by black hole binary inspiral and mergers enable unprecedented strong-field tests of gravity, requiring accurate theoretical modelling of the expected signals in extensions of General Relativity. In this paper we model the
This is an extended summary of the two parallel sessions held at MG11: PPN1 ``Strong Gravity and Binaries (chaired by L.B. and L.G.) and PPN2 ``Post-Newtonian Dynamics in Binary Objects (chaired by G.S.). The aims and contents of these sessions were
We study the post-Newtonian dynamics of black hole binaries in Einstein-scalar-Gauss-Bonnet gravity theories. To this aim we build static, spherically symmetric black hole solutions at fourth order in the Gauss-Bonnet coupling $alpha$. We then skelet
There are theoretical frameworks, such as the large extra dimension models, which predict the strengthening of the gravitational field in short distances. Here we obtain new empiric constraints for deviations of standard gravity in the atomic length
Several model-independent parameterizations of deviations from General Relativity have been developed to test Einsteins theory. Although these different parameterizations were developed for different gravitational observables, they ultimately all tes