Articles de revues : « Morris and Thorne »

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Culetu, Hristu. « On a particular Morris–Thorne wormhole ». Physica Scripta 90, n^o 8 (16 juin 2015) : 085001. http://dx.doi.org/10.1088/0031-8949/90/8/085001.

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Fayyaz, I., et M. Farasat Shamir. « Morris–Thorne wormhole with Karmarkar condition ». Chinese Journal of Physics 66 (août 2020) : 553–59. http://dx.doi.org/10.1016/j.cjph.2020.05.018.

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Eyasmin, Sabina, Dhyanesh Chakraborty et Mousumi Sarkar. « Curvature properties of Morris-Thorne wormhole metric ». Journal of Geometry and Physics 174 (avril 2022) : 104457. http://dx.doi.org/10.1016/j.geomphys.2022.104457.

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Müller, Thomas. « Visual appearance of a Morris–Thorne-wormhole ». American Journal of Physics 72, n^o 8 (août 2004) : 1045–50. http://dx.doi.org/10.1119/1.1758220.

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Godani, Nisha. « Stable Morris Thorne wormholes supported by non-exotic matter ». International Journal of Geometric Methods in Modern Physics 18, n^o 11 (2 juillet 2021) : 2150170. http://dx.doi.org/10.1142/s021988782150170x.

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The present work is focused on the study of traversable wormholes, proposed by Morris and Thorne [Wormholes in spacetime and their use for interstellar travel: A tool for teaching general relativity, Am. J. Phys. 56 (1988) 395], using the background of modified gravity. It is performed by using the models: I. [Formula: see text], II. [Formula: see text] and III. [Formula: see text], where [Formula: see text], [Formula: see text] and [Formula: see text] are constants. The Model I belongs to the theory of [Formula: see text] gravity, Model II belongs to the theory of [Formula: see text] gravity and Model III is a combination of Models I and II. These functions have been taken into account for the exploration of wormhole solutions. The shape function, a wormhole metric function, is newly defined which satisfies the flare out condition. Further, the stability condition and energy conditions, namely null, weak and dominant energy conditions, have been examined with respect to each model.

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Godani, Nisha, et Gauranga C. Samanta. « Non violation of energy conditions in wormholes modeling ». Modern Physics Letters A 34, n^o 28 (13 septembre 2019) : 1950226. http://dx.doi.org/10.1142/s0217732319502262.

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Morris and Thorne [M. S. Morris and K. S. Thorne, Am. J. Phys. 56, 395 (1988)] proposed geometrical objects called traversable wormholes that act as bridges in connecting two spacetimes or two different points of the same spacetime. The geometrical properties of these wormholes depend upon the choice of the shape function. In the literature, these are studied in modified gravities for different types of shape functions. In this paper, the traversable wormholes having shape function [Formula: see text] are explored in [Formula: see text] gravity with [Formula: see text], where [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] are real constants. For different values of constants in function [Formula: see text], the analysis is done in various cases. In each case, the energy conditions, equation of state parameter and anisotropic parameter are determined.

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HONG, SOON-TAE, et SUNG-WON KIM. « CAN WORMHOLES HAVE NEGATIVE TEMPERATURES ? » Modern Physics Letters A 21, n^o 10 (28 mars 2006) : 789–93. http://dx.doi.org/10.1142/s0217732306019839.

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We study (3+1) Morris–Thorne wormhole to investigate its thermodynamic properties. It is shown that the wormhole temperature can be evaluated by exploiting Unruh effects. We also propose a possibility of negative temperature originated from exotic matter distribution of the wormhole.

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Bandyopadhyay, Tanwi, et Ujjal Debnath. « Accretions of Tsallis, Rényi and Sharma–Mittal dark energies onto higher-dimensional Schwarzschild black hole and Morris–Thorne wormhole ». Modern Physics Letters A 36, n^o 12 (24 mars 2021) : 2150081. http://dx.doi.org/10.1142/s0217732321500814.

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In this work, we study the dark energy accretion phenomena onto [Formula: see text]-dimensional Schwarzschild black hole and [Formula: see text]-dimensional Morris–Thorne wormhole. We obtain the [Formula: see text]-dimensional Schwarzschild black hole mass and [Formula: see text]-dimensional Morris–Thorne wormhole mass and their rate of change of masses due to accretion. For the dark energy component, we consider Tsallis, modified Rényi and “modified” Sharma–Mittal holographic dark energy (HDE) and new agegraphic dark energy (NADE). We also find the black hole mass and the wormhole mass in terms of redshift when cold dark matter and the specified forms of dark energies accrete onto them. In most cases, the black hole mass increases, and wormhole mass decreases for HDE and NADE accretions. The only exception is the Sharma–Mittal NADE, where the black hole mass decreases and wormhole mass increases during the evolution of the Universe. However, the slope of increasing/decreasing mass significantly depends on the dimension in almost all cases.

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Chattopadhyay, Surajit, Antonio Pasqua et Irina Radinschi. « Accreting Scalar-Field Models of Dark Energy Onto Morris-Thorne Wormhole ». Zeitschrift für Naturforschung A 71, n^o 10 (1 octobre 2016) : 949–60. http://dx.doi.org/10.1515/zna-2016-0241.

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AbstractThe present paper reports a study on accreting tachyon, Dirac-Born-Infeld essence and h-essence scalar field models of dark energy onto Morris-Thorne wormhole. Using three different parameterisation schemes and taking $H\, = \,{H_0}\, + \,{{{H_1}} \over t}$, we have derived the mass of the wormhole for all of the three parameterisation schemes that are able to get hold of both quintessence and phantom behaviour. With suitable choice of parameters, we observed that accreting scalar field dark energy models are increasing the mass of the wormhole in the phantom phase and the mass is decreasing in the quintessence phase. Finally, we have considered accretion with power law form of scale factor and without any parameterisation scheme for the equation of state parameter and observed the fact that phantom-type dark energy supports the existence of wormholes.

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Novikov, I. D., et A. A. Shatskiy. « Stability analysis of a Morris-Thorne-Bronnikov-Ellis wormhole with pressure ». Journal of Experimental and Theoretical Physics 114, n^o 5 (mai 2012) : 801–4. http://dx.doi.org/10.1134/s1063776112040127.

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Kim, Sung-Won. « Flare-out condition of a Morris-Thorne wormhole and finiteness of pressure ». Journal of the Korean Physical Society 63, n^o 10 (novembre 2013) : 1887–91. http://dx.doi.org/10.3938/jkps.63.1887.

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Samanta, Gauranga C., et Nisha Godani. « Wormhole modeling supported by non-exotic matter ». Modern Physics Letters A 34, n^o 28 (13 septembre 2019) : 1950224. http://dx.doi.org/10.1142/s0217732319502249.

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In the present paper, the modeling of traversable wormholes, proposed by Morris and Thorne [Am. J. Phys. 56, 395 (1988)], is performed within the [Formula: see text] gravity with particular viable case [Formula: see text], where [Formula: see text], [Formula: see text] and [Formula: see text]. The energy conditions are analyzed using the shape function [Formula: see text] defined by Godani and Samanta [Int. J. Mod. Phys. D 28, 1950039 (2018)] and the geometric nature of wormholes is analyzed.

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Kang, YuRi, et Sung-Won Kim. « The gravitational perturbation of a Morris–Thorne wormhole and the Newman–Penrose formalism ». Classical and Quantum Gravity 37, n^o 10 (27 avril 2020) : 105012. http://dx.doi.org/10.1088/1361-6382/ab7dd8.

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Mattingly, Brandon, Abinash Kar, William Julius, Matthew Gorban, Cooper Watson, MD Ali, Andrew Baas et al. « Curvature Invariants for Lorentzian Traversable Wormholes ». Universe 6, n^o 1 (9 janvier 2020) : 11. http://dx.doi.org/10.3390/universe6010011.

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The curvature invariants of three Lorentzian wormholes are calculated and plotted in this paper. The plots may be inspected for discontinuities to analyze the traversability of a wormhole. This approach was formulated by Henry, Overduin, and Wilcomb for black holes (Henry et al., 2016). Curvature invariants are independent of coordinate basis, so the process is free of coordinate mapping distortions and the same regardless of your chosen coordinates (Christoffel, E.B., 1869; Stephani, et al., 2003). The four independent Carminati and McLenaghan (CM) invariants are calculated and the nonzero curvature invariant functions are plotted (Carminati et al., 1991; Santosuosso et al., 1998). Three traversable wormhole line elements analyzed include the (i) spherically symmetric Morris and Thorne, (ii) thin-shell Schwarzschild wormholes, and (iii) the exponential metric (Visser, M., 1995; Boonserm et al., 2018).

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Radinschi, Irina, Theophanes Grammenos, Andromahi Spanou, Surajit Chattopadhyay et Marius Mihai Cazacu. « Landau–Lifshitz and Weinberg Energy Distributions for the Static Regular Simpson–Visser Space-Time Geometry ». Symmetry 14, n^o 5 (28 avril 2022) : 900. http://dx.doi.org/10.3390/sym14050900.

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The symmetric Landau–Lifshitz and Weinberg energy–momentum complexes are utilized in order to determine the energy distribution in a four-dimensional, static and spherically symmetric regular Simpson–Visser space-time geometry. For different values of the metric parameter a, the static Simpson–Visser space-time geometry corresponds to the Schwarzschild black hole solution, to a regular black hole solution with a one-way spacelike throat, to a one-way wormhole solution with an extremal null throat, or to a traversable Morris–Thorne wormhole solution. Both symmetric prescriptions yield a zero momentum, while the energy distributions calculated have an expression dependent on the mass m, the radial coordinate r, and the metric parameter a. Some special limiting cases of the results derived are considered, while a possible astrophysical application to questions of gravitational lensing is indicated.

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Radinschi, Irina, Theophanes Grammenos, Gargee Chakraborty, Surajit Chattopadhyay et Marius Mihai Cazacu. « Einstein and Møller Energy-Momentum Distributions for the Static Regular Simpson–Visser Space-Time ». Symmetry 13, n^o 9 (3 septembre 2021) : 1622. http://dx.doi.org/10.3390/sym13091622.

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Energy-momentum localization for the four-dimensional static and spherically symmetric, regular Simpson–Visser black hole solution is studied by use of the Einstein and Møller energy-momentum complexes. According to the particular values of the parameter of the metric, the static Simpson–Visser solution can possibly describe the Schwarzschild black hole solution, a regular black hole solution with a one-way spacelike throat, a one-way wormhole solution with an extremal null throat, or a traversable wormhole solution of the Morris–Thorne type. In both prescriptions it is found that all the momenta vanish, and the energy distribution depends on the mass m, the radial coordinate r, and the parameter a of the Simpson–Visser metric. Several limiting cases of the results obtained are discussed, while the possibility of astrophysically relevant applications to gravitational lensing issues is pointed out.

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Rehman, Mudassar, et Khalid Saifullah. « Thermodynamics of traversable wormholes in f(R,T) gravity ». International Journal of Geometric Methods in Modern Physics 18, n^o 11 (10 juillet 2021) : 2150175. http://dx.doi.org/10.1142/s0219887821501759.

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In this paper, we discuss thermodynamics for spherically symmetric and static traversable wormholes which include Morris–Thorne wormholes and charged wormholes in the background of [Formula: see text] gravity. The local coordinates have been used to find trapping horizons of these objects and generalized surface gravity has been worked out on the trapping horizons. The expression for the unified first law has also been derived from the gradient of Misner–Sharp energy with the help of gravitational field equations and from this law the first law of wormhole dynamics has been obtained. We have done this analysis for the simplest case of [Formula: see text] gravity where [Formula: see text], [Formula: see text] and [Formula: see text] being the traces of the Ricci and stress–energy tensors. Also, we have extended these thermodynamic results to non-minimal curvature-matter coupling.

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Tefo, R. C., P. H. Logbo, M. J. S. Houndjo et J. Tossa. « New traversable wormhole solutions in f(T) gravity ». International Journal of Modern Physics D 28, n^o 04 (mars 2019) : 1950065. http://dx.doi.org/10.1142/s0218271819500652.

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In this paper, we search for dynamical traversable wormhole solutions in the modified [Formula: see text] theory of gravity, [Formula: see text] being the torsion scalar. For such a wormhole, the time dependence is inserted in the static traversable wormhole metric of Morris and Thorne. Two set of tetrads are adopted: the diagonal and the nondiagonal tetrads. The diagonal set of tetrads constrains and reduces [Formula: see text] model to teleparallel theory where usual solutions have been found. With diagonal set of tetrads, free from the teleparallel theory constraint, our results show that the existence of traversable wormhole is possible only for nondynamical spacetime metric, i.e. static traversable wormhole solutions. Moreover we take into account energy condition analysis and the results show that the violation of null energy condition is not determinant for existence of static traversable wormhole solutions.

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Varieschi, Gabriele U., et Kellie L. Ault. « Wormhole geometries in fourth-order conformal Weyl gravity ». International Journal of Modern Physics D 25, n^o 06 (mai 2016) : 1650064. http://dx.doi.org/10.1142/s0218271816500644.

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We present an analysis of the classic wormhole geometries based on conformal Weyl gravity, rather than standard general relativity. The main characteristics of the resulting traversable wormholes remains the same as in the seminal study by Morris and Thorne, namely, that effective super-luminal motion is a viable consequence of the metric. Improving on previous work on the subject, we show that for particular choices of the shape and redshift functions the wormhole metric in the context of conformal gravity does not violate the main energy conditions at or near the wormhole throat. Some exotic matter might still be needed at the junction between our solutions and flat spacetime, but we demonstrate that the averaged null energy condition (as evaluated along radial null geodesics) is satisfied for a particular set of wormhole geometries. Therefore, if fourth-order conformal Weyl gravity is a correct extension of general relativity, traversable wormholes might become a realistic solution for interstellar travel.

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Shweta, Ambuj Kumar Mishra et Umesh Kumar Sharma. « Traversable wormhole modelling with exponential and hyperbolic shape functions in F(R,T) framework ». International Journal of Modern Physics A 35, n^o 25 (10 septembre 2020) : 2050149. http://dx.doi.org/10.1142/s0217751x20501493.

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The concept of traversable wormhole, a hypothetical tunnel-like structure is initially proposed by Morris and Thorne (Am. J. Phys. 56, 395 (1988)) by using Einstein’s general relativity theory. Harko et al. (Phys. Rev. D 84, 024020 (2011)) defined [Formula: see text] gravity as an extended gravitational theory having terms [Formula: see text] and [Formula: see text] as Ricci scalar and trace of energy momentum respectively. In this article, we explore wormhole models for the framework of [Formula: see text] gravity by using two different shape functions. The first shape function is [Formula: see text], [Formula: see text] (proposed by Mishra and Sharma, arXiv:2003.00298v1 , 2020) and second is a hyperbolic shape function which is of the form [Formula: see text]. Geometrical behavior of wormholes are discussed in anisotropic scenario by using equation of state [Formula: see text]. The stability of models are analyzed by using equilibrium condition and determining gravitational force, anisotropic force, hydrostatic force and force due to modified gravity. For the validation of null energy condition and weak energy condition, significant role of shape function is illustrated for the presence of nonexotic matter.

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Kim, Sung-Won. « Evolution of cosmological horizons of wormhole cosmology ». International Journal of Modern Physics D 29, n^o 12 (28 juillet 2020) : 2050079. http://dx.doi.org/10.1142/s0218271820500790.

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Recently, we solved Einstein’s field equations to obtain the exact solution of the cosmological model with the Morris–Thorne-type wormhole. We found the apparent horizons and analyzed their geometric natures, including the causal structures. We also derived the Hawking temperature near the apparent cosmological horizon. In this paper, we investigate the dynamic properties of the apparent horizons under the matter-dominated universe and lambda-dominated universe. As a more realistic universe, we also adopt the [Formula: see text]CDM universe which contains both the matter and lambda. The past light cone and the particle horizon are examined for what happens in the case of the model with wormhole. Since the spatial coordinates of the spacetime with the wormhole are limited outside the throat, the past light cone can be operated by removing the smaller-than-wormhole region. The past light cones without wormhole begin to start earlier than the past light cones with wormhole in conformal time-proper distance coordinates. The light cone consists of two parts: the information from our universe and the information from other universe or far distant region through the wormhole. Therefore, the particle horizon distance determined from the observer’s past light cone cannot be defined in a unique way.

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HAYWARD, SEAN A. « DYNAMIC WORMHOLES ». International Journal of Modern Physics D 08, n^o 03 (juin 1999) : 373–82. http://dx.doi.org/10.1142/s0218271899000286.

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A new framework is proposed for general dynamic wormholes, unifying them with black holes. Both are generically defined locally by outer trapping horizons, temporal for wormholes and spatial or null for black and white holes. Thus wormhole horizons are two-way traversible, while blackhole and whitehole horizons are only one-way traversible. It follows from the Einstein equation that the null energy condition is violated everywhere on a generic wormhole horizon. It is suggested that quantum inequalities constraining negative energy break down at such horizons. Wormhole dynamics can be developed as for blackhole dynamics, including a reversed second law and a first law involving a definition of wormhole surface gravity. Since the causal nature of a horizon can change, being spatial under positive energy and temporal under sufficient negative energy, blackholes and wormholes are interconvertible. In particular, if a wormhole's negative-energy source fails, it may collapse into a blackhole. Conversely, irradiating a blackhole horizon with negative energy could convert it into a wormhole horizon. This also suggests a possible final state of blackhole evaporation: a stationary wormhole. The new framework allows a fully dynamical description of the operation of a wormhole for practical transport, including the back-reaction of the transported matter on the wormhole. As an example of a matter model, a Klein–Gordon field with negative gravitational coupling is a source for a static wormhole of Morris and Thorne.

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Vasihoun, Mahary, et Eduardo Guendelman. « Gravitational and topological effects on $\sqrt{-F^2}$ confinement dynamics ». International Journal of Modern Physics A 29, n^o 23 (16 septembre 2014) : 1430042. http://dx.doi.org/10.1142/s0217751x14300427.

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We present a review, of recent developments on nonlinear gauge theory containing a [Formula: see text] term coupled to gravity. We start by showing some of the confining features of this theory in flat space–time. We then consider the coupling, of this nonlinear term, to gravity and discuss two types of spherically symmetric solutions. One of them has a tube topology, that is [Formula: see text], or of the Levi-Civita–Bertotti–Robinson (LCBR) type, where the metric coefficient gθθ is a constant. The other type of solutions, Reissner–Nordström–de Sitter (RNdS), with gθθ = r2, where r is a radial variable allowed to have all values from zero to infinity. Next we consider the matching of these solutions via lightlike, and subsequently, timelike membranes and show the topologically induced effects of "hiding of charge," where a charged particle can appear neutral to an external observer looking at it from the RNdS region and the "confining of charge" in a wormhole throat, where two opposite charges are at the opposite sides of a wormhole throats. We proceed with some applications to extended theories of general relativity, in the form of quadratic gravity model (F(R)), then wormholes arise naturally from the nonlinear electromagnetic field rather than requiring exotic matter to generate a predesigned wormhole geometry (Morris–Thorne approach), in another model considered here we have, in addition to quadratic gravity, a dilaton field (ϕ), where we find wormhole solutions with de Sitter asymptotics and confinement–deconfinement transition effects as function of the dilaton vacuum expectation value. The last application we present is to the "Two Measure Theory," where in addition to the metric volume element, [Formula: see text], we consider a new, metric independent, volume element Φ. Finally we conclude and summarize our findings.

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Morris, Julia M., et Curtis A. Thorne. « Abstract 3087 : The identification and characterization of FOLFOX chemotherapy resistant cell lineages in colorectal cancer organoids ». Cancer Research 82, n^o 12_Supplement (15 juin 2022) : 3087. http://dx.doi.org/10.1158/1538-7445.am2022-3087.

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Abstract Resistance to chemotherapy drugs is a well-documented issue inhibiting the treatment of a wide variety of cancers. Colorectal cancer (CRC) is the third most common neoplasm worldwide and has the third highest mortality rate. However, the longtime gold-standard FOLFOX chemotherapy regimen, consisting of 5-FU and Oxaliplatin, results in only 70% survival rates in Stage 3 CRC patients, worse in Stage 4. More recent targeted therapies have marginally improved on this number, but the fact remains that CRC represents a highly heterogeneous neoplasm and resistance to standard chemotherapeutic regimens poses a significant barrier in treating this devastating disease. There is an immediate need to better understand how this resistance arises. We hypothesize that a small number of cells with high phenotypic plasticity (HPP) are able to remain dormant during the initial chemotherapy treatment then reenter the cell cycle to cause recurrence and metastasis months or even years after treatment has concluded. Patient-derived organoids (PDOs) are a recently developed ex vivo model that allows for the study and extensive characterization of such HPP cell populations that may be found in patient tumors. We are developing and expanding various PDO populations to examine them genotypically and phenotypically on the single-cell level through RNA sequencing and high throughput imaging, respectively. By identifying these HPP cell populations, we then discover drugs that prevent the development of drug-resistant subpopulations. In the long term, we use our tumor heterogeneity profile to develop models that predict the responsiveness of tumors, including their drug-resistant HPP subpopulations, to well-documented and clinically used oncology drugs, streamlining treatment and improving survival outcomes. Citation Format: Julia M. Morris, Curtis A. Thorne. The identification and characterization of FOLFOX chemotherapy resistant cell lineages in colorectal cancer organoids [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3087.

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Godani, Nisha, et Gauranga C. Samanta. « Traversable wormholes and energy conditions with two different shape functions in f(R) gravity ». International Journal of Modern Physics D 28, n^o 02 (janvier 2019) : 1950039. http://dx.doi.org/10.1142/s0218271819500391.

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Traversable wormholes, tunnel-like structures introduced by Morris and Thorne [Am. J. Phys. 56 (1988) 395], have a significant role in connection of two different spacetimes or two different parts of the same spacetime. The characteristics of these wormholes depend upon the redshift and shape functions which are defined in terms of radial coordinate. In literature, several shape functions are defined and wormholes are studied in [Formula: see text] gravity with respect to these shape functions [F. S. N. Lobo and M. A. Oliveira, Phys. Rev. D 80 (2009) 104012; H. Saiedi and B. N. Esfahani, Mod. Phys. Lett. A 26 (2011) 1211; S. Bahamonde, M. Jamil, P. Pavlovic and M. Sossich, Phys. Rev. D 94 (2016) 044041]. In this paper, two shape functions (i) [Formula: see text] and (ii) [Formula: see text], [Formula: see text], are considered. The first shape function is newly defined, however, the second one is collected from the literature [M. Cataldo, L. Liempi and P. Rodríguez, Eur. Phys. J. C 77 (2017) 748]. The wormholes are investigated for each type of shape function in [Formula: see text] gravity with [Formula: see text], where [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] are real constants. Varying the parameter [Formula: see text] or [Formula: see text], [Formula: see text] model is studied in five subcases for each type of shape function. In each case, the energy density, radial and tangential pressures, energy conditions that include null energy condition, weak energy condition, strong energy condition and dominated energy condition and anisotropic parameter are computed. The energy density is found to be positive and all energy conditions are obtained to be violated which support the existence of wormholes. Also, the equation-of-state parameter is obtained to possess values less than [Formula: see text], that shows the presence of the phantom fluid and leads toward the expansion of the universe.

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Godani, Nisha, et Gauranga C. Samanta. « Wormhole modeling in R2 gravity with linear trace term ». International Journal of Modern Physics A 35, n^o 08 (20 mars 2020) : 2050045. http://dx.doi.org/10.1142/s0217751x20500451.

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Morris and Thorne1 proposed traversable wormholes, hypothetical connecting tools, using the concept of Einstein’s general theory of relativity. In this paper, the modification of general relativity (in particular [Formula: see text] theory of gravity defined by Harko et al.2) is considered, to study the traversable wormhole solutions. The function [Formula: see text] is considered as [Formula: see text], where [Formula: see text] and [Formula: see text] are controlling parameters. The shape and redshift functions appearing in the metric of wormhole structure have significant contribution in the development of wormhole solutions. We have considered both variable and constant redshift functions with a logarithmic shape function. The energy conditions are examined, geometric configuration is analyzed and the radius of the throat is determined in order to have wormhole solutions in absence of exotic matter.

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Gómez-Padilla, Eurídice, Paola C. Bello-Medina, Uriel León-Jacinto, Erika Orta-Salazar, Gina L. Quirarte, Víctor Ramírez-Amaya, Roberto A. Prado-Alcalá et Sofía Díaz-Cintra. « Morris water maze overtraining increases the density of thorny excrescences in the basal dendrites of CA3 pyramidal neurons ». Behavioural Brain Research 379 (février 2020) : 112373. http://dx.doi.org/10.1016/j.bbr.2019.112373.

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Padilla-Gómez, Eurídice, Paola C. Bello-Medina, Uriel León-Jacinto, Erika Orta-Salazar, Gina L. Quirarte, Víctor Ramírez-Amaya, Roberto A. Prado-Alcalá et Sofía Díaz-Cintra. « Corrigendum to "Morris water maze overtraining increases the density of thorny excrescences in the basal dendrites of CA3 pyramidal neurons" [Behav. Brain Res. 379 (2020) 112373] ». Behavioural Brain Research 384 (avril 2020) : 112523. http://dx.doi.org/10.1016/j.bbr.2020.112523.

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SALAM, Jekendra Singh, Priyadarshini SALAM, Kumar Singh POTSHANGBAM et Biman Kumar DUTTA. « Effect of Domestic Processing Methods on Dry Matter, Total Sugar, Phenolics and Mineral Composition in Different Developmental Stages of Parkia roxburghii G. (Don.) Pods ». Notulae Scientia Biologicae 5, n^o 1 (23 février 2013) : 50–56. http://dx.doi.org/10.15835/nsb518244.

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Parkia roxburghii is considered delicious in the Northeastern part of India, especially in the state of Manipur. Though it is widely used, information about the biochemical composition and its changes, after processing, is hardly available. In the present experiment, effect of processing methods on dry matter, soluble sugar, phenolics and mineral composition in different developmental stages of P. roxburghii pods were studied. Total soluble sugar (TSS), total phenols (TP), and orthodihydric phenols (ODHP) were determined as per the methods of Morris (1948), Bray and Thorpe (1954) and Mahadevan and Sridhar (1986). Sodium (Na), potassium (K), sulphur (S) and phosphorus (P) were estimated as per the procedures of Tandon (1993). Calcium (Ca), magnesium (Mg), manganese (Mn), zinc (Zn), iron (Fe), copper (Cu) and cobalt (Co) were analyzed in an atomic absorption spectrophotometer. Processing methods reduced dry matter, soluble sugar and phenolics in all the stages of the pod. TP and ODHP lost up to the extent of 72.78% in tender stage due to ordinary cooking, while higher loss of ODHP recorded in immature stage of the pod due to pressure cooking. Ca, Mg, K and Zn in different stages were found to be affected significantly by different methods of cooking, while no such changes were observed in case of S, P, Fe, Mn and Cu. The level of iron amongst the micro minerals is appreciably high recording up to 51.0 mg/100 g in the immature stage of the pod. As iron, zinc and manganese are antioxidant micronutrients, their higher presence in P. roxburghii might be of some nutritional importance.

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Castro-Chávez, Fernando. « Restaurando a las viñetas de La feria. El rescate de las viñetas originales de 1963 de La feria de Arreola ante la versión de 1971 de Joaquín Mortiz y las de la Editorial Planeta Mexicana ». Argos 7, n^o 19 (1 juin 2019) : 58–111. http://dx.doi.org/10.32870/argos.v7.n19.5a20.

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Y aquí estoy yo, rescatando a las viñetas originales de La Feria de Arreola de 1963, incluyendo a las de su portada: Las veinte adulteraciones presentes en la edición de 1971 de Joaquín Mortiz (JM: “Obras de J. J. Arreola: La feria”), más una en la versión del FCE (“Fondo de Cultura Económica”), también llamada “Obras” de Arreola, de 1995, al ser comparadas con las de los 60s de Joaquín Mortiz. Es decir, que las veintiún adulteraciones a las viñetas de La Feria de Arreola, dibujadas originalmente por Vicente Rojo, expresan quince cambios con respecto a los iconos originales más cinco inversiones de los mismos y una clara alteración en la numeración visible en una de ellas: la última, alteración del FCE, es la del dominó en 2 – 1 que es cambiada a 1 – 1 (siendo solamente 80 las viñetas originales que se repiten a sí mismas para darnos un total de 294, incluyendo a las cinco que están presentes en la portada original, portada a la que Orso Arreola Sánchez, hijo de Arreola, me sugiriera incluir en la suma total), apareciendo estos errores en las ediciones subsiguientes, hasta llegar al reemplazo de todas las viñetas mediante siete nuevos dibujos no relacionados, por parte de la “Editorial Planeta Mexicana” (serie booket, al menos desde el 2015); mi petición es que La Feria pueda ser restaurada a sus viñetas originales, incluyendo aquellas cinco que aparecieron en la portada de las ediciones y reimpresiones iniciales de los sesentas publicadas por Joaquín Mortiz.

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Marín, Carlos A. « Agujeros de gusano : solución exponencial ». ACI Avances en Ciencias e Ingenierías 2, n^o 2 (1 juin 2010). http://dx.doi.org/10.18272/aci.v2i2.24.

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Se revisan las propiedades fundamentales de los agujeros de gusano del tipo Morris- Thorne, así como las condiciones de energía (NEC, WEC, SEC, DEC ) para dichos agujeros. Se introduce una nueva solución de carácter exponencial para las ecuaciones derivadas por Morris y Thorne para los mencionados agujeros y, finalmente, se procede a calcular el tiempo que se demoraría un viajero en atravesar un agujero de gusano con función de forma exponencial.

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Lemos, José P. S., Francisco S. N. Lobo et Sérgio Quinet de Oliveira. « Morris-Thorne wormholes with a cosmological constant ». Physical Review D 68, n^o 6 (5 septembre 2003). http://dx.doi.org/10.1103/physrevd.68.064004.

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Cataldo, Mauricio, Luis Liempi et Pablo Rodríguez. « Morris-Thorne wormholes in static pseudospherically symmetric spacetimes ». Physical Review D 91, n^o 12 (12 juin 2015). http://dx.doi.org/10.1103/physrevd.91.124039.

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Chanda, A., S. Dey et B. C. Paul. « Morris–Thorne wormholes in modified f(R, T) gravity ». General Relativity and Gravitation 53, n^o 8 (août 2021). http://dx.doi.org/10.1007/s10714-021-02847-7.

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Jusufi, Kimet. « Conical Morris-Thorne wormholes with a global monopole charge ». Physical Review D 98, n^o 4 (8 août 2018). http://dx.doi.org/10.1103/physrevd.98.044016.

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Müller, Thomas. « Exact geometric optics in a Morris-Thorne wormhole spacetime ». Physical Review D 77, n^o 4 (26 février 2008). http://dx.doi.org/10.1103/physrevd.77.044043.

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Kuhfittig, Peter K. F. « On the Nature of Exotic Matter in Morris-Thorne Wormholes ». New Horizons in Mathematical Physics 4, n^o 3 (31 décembre 2020). http://dx.doi.org/10.22606/nhmp.2020.43001.

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It is well known that phantom energy, which is characterized by the equation of state p = ωρ, ω < −1, can support Morris-Thorne wormholes since it leads to a violation of the null energy condition. The purpose of this note is to show that the converse is also true in the following sense: for a typical shape function, the equation of state of exotic matter in the vicinity of the throat is given by p↓r = ωρ, ω < −1, where pr is the radial pressure.

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Kuhfittig, Peter K. F. « Accounting for the large radial tension in Morris–Thorne wormholes ». European Physical Journal Plus 135, n^o 6 (juin 2020). http://dx.doi.org/10.1140/epjp/s13360-020-00511-8.

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Mazharimousavi, S. Habib, Zahra Amirabi et M. Halilsoy. « Magnetic Morris–Thorne wormhole in $$2+1$$ 2 + 1 -dimensions ». General Relativity and Gravitation 48, n^o 11 (5 octobre 2016). http://dx.doi.org/10.1007/s10714-016-2139-x.

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Genc, Onur. « Some Aspects of Morris-Thorne Wormhole in Scalar Tensor Theory ». International Journal of Modern Physics D, 6 janvier 2023. http://dx.doi.org/10.1142/s0218271823500141.

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Forghani, S. Danial, S. Habib Mazharimousavi et M. Halilsoy. « Fate of a thin-shell wormhole powered by Morris-Thorne wormhole ». European Physical Journal Plus 133, n^o 12 (décembre 2018). http://dx.doi.org/10.1140/epjp/i2018-12409-y.

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Debnath, Ujjal. « Accretions of various types of dark energies onto Morris–Thorne wormhole ». European Physical Journal C 74, n^o 5 (mai 2014). http://dx.doi.org/10.1140/epjc/s10052-014-2869-4.

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Cremona, Francesco, Francesca Pirotta et Livio Pizzocchero. « On the linear instability of the Ellis–Bronnikov–Morris–Thorne wormhole ». General Relativity and Gravitation 51, n^o 1 (janvier 2019). http://dx.doi.org/10.1007/s10714-019-2501-x.

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Bandyopadhyay, Tanwi, et Ujjal Debnath. « Fluid accretion upon higher-dimensional wormhole and black hole for parameterized deceleration parameter ». International Journal of Geometric Methods in Modern Physics, 15 juillet 2022. http://dx.doi.org/10.1142/s0219887822501821.

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In this work, we study some parameterizations of the deceleration parameter and investigate the accretion of the fluid in these parameterized models upon the higher-dimensional black hole (BH) and wormholes. For the undergoing analysis, [Formula: see text]-dimensional wormhole (proposed by Morris and Thorne) and Schwarzschild BH were chosen in the backdrop of higher-dimensional Friedmann–Robertson–Walker (FRW) space-time. For these parameterized models, we analyze the change of masses of BH and wormhole in different dimensions.

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Li, Ai-chen, et Xin-Fei Li. « Morris-Thorne wormhole in the vector-tensor theories with Abelian gauge symmetry breaking ». Physical Review D 104, n^o 4 (3 août 2021). http://dx.doi.org/10.1103/physrevd.104.044006.

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Godani, Nisha, et Gauranga C. Samanta. « Deflection angle for charged wormhole in f(R,T) gravity ». International Journal of Geometric Methods in Modern Physics, 5 août 2021, 2150193. http://dx.doi.org/10.1142/s0219887821501930.

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This paper is focused on the study of charged wormholes which are combinations of Morris–Thorne wormhole and Reissner–Nordström spacetime. Gravitational lensing is an important tool which has been adopted to detect various objects like wormholes using the notion of deflection angle. In this work, we have evaluated deflection angle with and without using the strong field limit coefficients and compared the results. Further, exact charged wormhole solutions are obtained in [Formula: see text] gravity and the nature of the energy conditions is examined.

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Sokoliuk, Oleksii, et Alexander Baransky. « On the existence and stability of traversable wormhole solutions in modified theories of gravity ». European Physical Journal C 81, n^o 8 (août 2021). http://dx.doi.org/10.1140/epjc/s10052-021-09560-4.

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AbstractWe study Morris–Thorne static traversable wormhole solutions in different modified theories of gravity. We focus our study on the quadratic gravity $$f({\mathscr {R}}) = {\mathscr {R}}+a{\mathscr {R}}^2$$ f ( R ) = R + a R 2 , power-law $$f({\mathscr {R}}) = f_0{\mathscr {R}}^n$$ f ( R ) = f 0 R n , log-corrected $$f({\mathscr {R}})={\mathscr {R}}+\alpha {\mathscr {R}}^2+\beta {\mathscr {R}}^2\ln \beta {\mathscr {R}}$$ f ( R ) = R + α R 2 + β R 2 ln β R theories, and finally on the exponential hybrid metric-Palatini gravity $$f(\mathscr {\hat{R}})=\zeta \bigg (1+e^{-\frac{\hat{{\mathscr {R}}}}{\varPhi }}\bigg )$$ f ( R ^ ) = ζ ( 1 + e - R ^ Φ ) . Wormhole fluid near the throat is adopted to be anisotropic, and redshift factor to have a constant value. We solve numerically the Einstein field equations and we derive the suitable shape function for each MOG of our consideration by applying the equation of state $$p_t=\omega \rho $$ p t = ω ρ . Furthermore, we investigate the null energy condition, the weak energy condition, and the strong energy condition with the suitable shape function b(r). The stability of Morris–Thorne traversable wormholes in different modified gravity theories is also analyzed in our paper with a modified Tolman–Oppenheimer–Voklov equation. Besides, we have derived general formulas for the extra force that is present in MTOV due to the non-conserved stress-energy tensor.

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Godani, Nisha. « Wormholes solutions in f(R,T) gravity with photon sphere at the throat ». International Journal of Geometric Methods in Modern Physics, 9 septembre 2021, 2150211. http://dx.doi.org/10.1142/s021988782150211x.

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This work is aimed at the study of traversable wormholes, proposed by Morris and Thorne [Wormholes in spacetime and their use for interstellar travel: A tool for teaching general relativity, Am. J. Phys. 56 (1988) 395], in the framework of [Formula: see text] gravity, where [Formula: see text], [Formula: see text] and [Formula: see text] are constants. The wormhole solutions are obtained and analyzed by using a simplest form of shape function. Further, the existence of photon spheres outside the throat of wormhole due to the gravitational lensing effect is detected.

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Takeuchi, Shingo. « Josephson junction formed in the wormhole space-time from the analysis of the critical temperature of BEC ». European Physical Journal C 81, n^o 12 (décembre 2021). http://dx.doi.org/10.1140/epjc/s10052-021-09855-6.

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AbstractIn this study, we consider a gas in the Morris–Thorne traversable wormhole space-time, and analyze the critical temperature of the Bose-Einstein condensate in the vicinity of its throat. Our results show that it is equal to zero. Then, from this result, we point out that a state analogous to the Josephson junction is always formed at any temperature in the vicinity of its throat. This is of interest as a gravitational phenomenology. Of course, there is the problem of the exotic matter, but we perform this work without treating it.

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Kuhfittig, Peter K. F. « Accounting for exotic matter and the extreme radial tension in Morris–Thorne wormholes of embedding class one ». European Physical Journal C 81, n^o 8 (août 2021). http://dx.doi.org/10.1140/epjc/s10052-021-09492-z.

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AbstractThe embedding of a curved spacetime in a higher-dimensional flat spacetime has continued to be a topic of interest in the general theory of relativity, as exemplified by the induced-matter theory. This paper deals with spacetimes of embedding class one, i.e., spacetimes that can be embedded in a five-dimensional flat spacetime. Einstein’s theory allows the fifth dimension to be either spacelike or timelike. By assuming the latter, this paper addresses two fundamental issues concerning Morris–Thorne wormholes, the origin of exotic matter and the frequently inexplicable enormous radial tension at the throat.

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