One dimensional wormhole corrosion in metals
Yang YangWeiyue ZhouSheng YinSarah Y. WangQin YuMatthew J. OlsztaYaqian ZhangSteven E. ZeltmannMingda LiMiaomiao JinDaniel K. SchreiberJim CistonMary ScottJohn R. ScullyRobert O. RitchieMark AstaJu LiMichael P. ShortAndrew M. Minor
50
Citation
75
Reference
10
Related Paper
Citation Trend
Abstract:
Corrosion is a ubiquitous failure mode of materials. Often, the progression of localized corrosion is accompanied by the evolution of porosity in materials previously reported to be either three-dimensional or two-dimensional. However, using new tools and analysis techniques, we have realized that a more localized form of corrosion, which we call 1D wormhole corrosion, has previously been miscategorized in some situations. Using electron tomography, we show multiple examples of this 1D and percolating morphology. To understand the origin of this mechanism in a Ni-Cr alloy corroded by molten salt, we combined energy-filtered four-dimensional scanning transmission electron microscopy and ab initio density functional theory calculations to develop a vacancy mapping method with nanometer-resolution, identifying a remarkably high vacancy concentration in the diffusion-induced grain boundary migration zone, up to 100 times the equilibrium value at the melting point. Deciphering the origins of 1D corrosion is an important step towards designing structural materials with enhanced corrosion resistance.Keywords:
Wormhole
Wormhole
Einstein field equations
Energy density
Cite
Citations (91)
The first part of this paper discusses a model for the theoretical construction of a simple traversable wormhole with zero density that depends on a preexisting black hole. By assuming the interconvertibilty of black holes and wormholes proposed by S.A. Hayward, it is shown that a toy model suggested by the first model may yield several possible transitions from the preexisting black hole to a wormhole. A final topic is the conversion to a wormhole by assuming a specific model for the exotic matter.
Wormhole
Black hole (networking)
Zero (linguistics)
Exotic matter
Cite
Citations (1)
In this paper we study classical general relativistic static wormhole configurations with pseudo-spherical symmetry. We show that in addition to the hyperbolic wormhole solutions discussed by Lobo and Mimoso in the Ref. Phys.\ Rev.\ D {\bf 82}, 044034 (2010), there exists another wormhole class, which is truly pseudo-spherical counterpart of spherical Morris-Thorne wormhole (contrary to the Lobo-Mimoso wormhole class), since all constraints originally defined by Morris and Thorne for spherically symmetric wormholes are satisfied. We show that, for both classes of hyperbolic wormholes the energy density, at the throat, is always negative, while the radial pressure is positive, contrary to the spherically symmetric Morris-Thorne wormhole. Specific hyperbolic wormholes are constructed and discussed by imposing different conditions for the radial and lateral pressures, or by considering restricted choices for the redshift and the shape functions. In particular, we show that an hyperbolic wormhole can not be sustained at the throat by phantom energy, and that there are pseudo-spherically symmetric wormholes supported by matter with isotropic pressure and characterized by space sections with an angle deficit (or excess).
Wormhole
Exotic matter
Phantom energy
Circular symmetry
Cite
Citations (0)
Wormhole
Value (mathematics)
Cite
Citations (1)
The general form of a stationary, axially symmetric traversable wormhole is discussed. This provides an explicit class of rotating wormholes that generalizes the static, spherically symmetric ones first considered by Morris and Thorne. In agreement with general analyses, it is verified that such a wormhole generically violates the null energy condition at the throat. However, for suitable model wormholes, there can be classes of geodesics falling through it which do not encounter any energy-condition-violating matter. The possible presence of an ergoregion surrounding the throat is also noted.
Wormhole
Energy condition
Exotic matter
Axial symmetry
Null (SQL)
Negative energy
Cite
Citations (210)
A new concept of a wormhole is reviewed. Classification of wormholes into three categories—static, space-like and time-like—is carried out, and the properties of each category are considered. The relation between wormholes and black holes is examined. The astrophysical properties of wormholes are investigated.
Wormhole
Cite
Citations (11)
After averaging over fermion couplings, SYK has a collective field description that sometimes has "wormhole" solutions. We study the fate of these wormholes when the couplings are fixed. Working mainly in a simple model, we find that the wormhole saddles persist, but that new saddles also appear elsewhere in the integration space -- "half-wormholes." The wormhole contributions depend only weakly on the specific choice of couplings, while the half-wormhole contributions are strongly sensitive. The half-wormholes are crucial for factorization of decoupled systems with fixed couplings, but they vanish after averaging, leaving the non-factorizing wormhole behind.
Wormhole
Cite
Citations (44)
Wormhole
Cite
Citations (5)
Wormhole
Exotic matter
Negative energy
Negative mass
Energy condition
Cite
Citations (9)
Exact wormhole solutions, while eagerly sought after, often have the appearance of being overly specialized or highly artificial. A case for the possible existence of traversable wormholes would be more compelling if an abundance of solutions could be found. It is shown in this note that for many of the wormhole geometries in the literature, the exact solutions obtained imply the existence of large sets of additional solutions.
Wormhole
Cite
Citations (16)