Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein’s equivalence principle (EEP) is well supported by experiments such as the Eotvos experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.

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The Confrontation Between General Relativity and Experiment

Advances in atomic physics, such as cooling and trapping of atoms and molecules and developments in frequency metrology, have added orders of magnitude to the precision of atom-based clocks and sensors. Applications extend beyond atomic physics and this article reviews using these new techniques to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics, and test the principles of general relativity.

Search for New Physics with Atoms and Molecules

For higher-derivative f(R) gravity, where R is the Ricci scalar, a class of models is proposed, which produce viable cosmology different from the ACDM at recent times and satisfy cosmological, Solar System, and laboratory tests. These models have both flat and de Sitter spacetimes as particular solutions in the absence of matter. Thus, a cosmological constant is zero in a flat spacetime, but appears effectively in a curved one for sufficiently large R. A “smoking gun” for these models would be a small discrepancy in the values of the slope of the primordial perturbation power spectrum determined from galaxy surveys and CMB fluctuations. On the other hand, a new problem for dark energy models based on f(R) gravity is pointed out, which is connected with the possible overproduction of new massive scalar particles (scalarons) arising in this theory in the very early Universe.

Disappearing cosmological constant in f(R) gravity

Most embeddings of the Standard Model into a more unified theory, in particular those based on supergravity or superstrings, predict the existence of a hidden sector of particles that have only very weak interactions with visible-sector Standard Model particles. Some of these exotic particle candidates [for instance, axions, axion-like particles, and hidden U(1) gauge bosons] may be very light, with masses in the subelectronvolt range, and may have very weak interactions with photons. Correspondingly, these very weakly interacting subelectronvolt particles (WISPs) may lead to observable effects in experiments (as well as in astrophysical and cosmological observations) searching for light shining through a wall, for changes in laser polarization, for nonlinear processes in large electromagnetic fields, and for deviations from Coulomb's law. We present the physics case and a status report of this emerging low-energy frontier of fundamental physics.

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The Low-Energy Frontier of Particle Physics

We conducted three torsion-balance experiments to test the gravitational inverse-square law at separations between 9.53 mm and $55\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$, probing distances less than the dark-energy length scale ${\ensuremath{\lambda}}_{d}=\sqrt[4]{\ensuremath{\hbar}c/{\ensuremath{\rho}}_{d}}\ensuremath{\approx}85\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$. We find with 95% confidence that the inverse-square law holds ($|\ensuremath{\alpha}|\ensuremath{\le}1$) down to a length scale $\ensuremath{\lambda}=56\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ and that an extra dimension must have a size $R\ensuremath{\le}44\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$.

/pdf/tests-of-the-gravitational-inverse-square-law-below-the-dark-3v7l70j8fb.pdf

Tests of the gravitational inverse-square law below the dark-energy length scale.

We used a torsion pendulum containing {approx_equal}10{sup 23} polarized electrons to search new interactions that couple to electron spin. We limit CP-violating interactions between the pendulum's electrons and unpolarized matter in the Earth or the Sun, test for rotation and boost-dependent preferred-frame effects using the Earth's rotation and velocity with respect to the entire cosmos, and search for exotic velocity-dependent potentials between polarized electrons and unpolarized matter in the Sun and Moon. We find CP-violating parameters |g{sub P}{sup e}g{sub S}{sup N}|/(({Dirac_h}/2{pi})c) 1 AU. We test for preferred-frame interactions of the form V=-{sigma}{sup e}{center_dot}A, V=-B{sigma}{sup e}{center_dot}v/c, or , where v is the velocity of the Earth with respect to the cosmic microwave background restframe and i, j represent the equatorial inertial coordinates X, Y, and Z. We constrain all 3 components of A, obtaining 1{sigma} upper limits |A{sub X,Y}|{<=}1.5x10{sup -22} eV and |A{sub Z}|{<=}4.4x10{sup -21} eV that may be compared to the benchmark value m{sub e}{sup 2}/M{sub Planck}=2x10{sup -17} eV. Interpreting our constraint on A in terms of noncommutative geometry, we obtain an upper bound of (355l{sub GUT}){sup 2} on the minimum observable area, where l{sub GUT}=({Dirac_h}/2{pi})c/(10{sup 16} GeV) is the grandmore » unification length. We find that |B|{<=}1.2x10{sup -19} eV. All 9 components of C are constrained at the 10{sup -17} to 10{sup -18} eV level. We determine 9 linear combinations of parameters of the standard model extension; rotational-noninvariant and boost-noninvariant terms are limited at roughly the 10{sup -31} GeV and 10{sup -27} GeV levels, respectively. Finally, we find that the gravitational mass of an electron spinning toward the galactic center differs by less than about 1 part in 10{sup 21} from an electron spinning in the opposite direction. As a byproduct of this work, the density of polarized electrons in Sm Co{sub 5} was measured to be (4.19{+-}0.19)x10{sup 22} cm{sup -3} at a field of 9.6 kG.« less

Preferred-Frame and CP-Violation Tests with Polarized Electrons

We used a torsion pendulum containing approximately 9 x 10(22) polarized electrons to search for CP-violating interactions between the pendulum's electrons and unpolarized matter in the laboratory's surroundings or the Sun, and to test for preferred-frame effects that would precess the electrons about a direction fixed in inertial space. We find, /g(P)(e)g(S)(N)//(Planck's constant x c) 1 AU. Our preferred-frame constraints, interpreted in the Kostelecký framework, set an upper limit on the parameter /b(e)/ <or= 5.0 x 10(-21) eV that should be compared to the benchmark value m(e)(2)/M(Planck)= 2 x 10(-17) eV.

New CP-Violation and Preferred-Frame Tests with Polarized Electrons

We tested the gravitational $1/{r}^{2}$ law using a stationary torsion-balance detector and a rotating attractor containing test bodies with both 18-fold and 120-fold azimuthal symmetries that simultaneously tests the $1/{r}^{2}$ law at two different length scales. We took data at detector-attractor separations between $52\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ and 3.0 mm. Newtonian gravity gave an excellent fit to our data, limiting with 95% confidence any gravitational-strength Yukawa interactions to ranges $l38.6\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$.

New Test of the Gravitational 1 /r 2 Law at Separations down to 52 μ m

http://absimage.aps.org/image/APR06/MWS_APR06-2006-000657.pdf

T. S. Cook

Papers

Tests of the gravitational inverse-square law below the dark-energy length scale.

Preferred-Frame and CP-Violation Tests with Polarized Electrons

New CP-Violation and Preferred-Frame Tests with Polarized Electrons

New Test of the Gravitational 1 /r 2 Law at Separations down to 52 μ m

New CP-violation and preferred-frame tests with polarized electrons