343 research outputs found
Spin and Rotations in Galois Field Quantum Mechanics
We discuss the properties of Galois Field Quantum Mechanics constructed on a
vector space over the finite Galois field GF(q). In particular, we look at
2-level systems analogous to spin, and discuss how SO(3) rotations could be
embodied in such a system. We also consider two-particle `spin' correlations
and show that the Clauser-Horne-Shimony-Holt (CHSH) inequality is nonetheless
not violated in this model.Comment: 21 pages, 11 pdf figures, LaTeX. Uses iopart.cls. Revised
introduction. Additional reference
Solving Pure Yang Mills in 2+1 Dimensions
We analytically compute the spectrum of the spin zero glueballs in the planar
limit of pure Yang-Mills theory in 2+1 dimensions. The new ingredient is
provided by our computation of a new non-trivial form of the ground state
wave-functional. The mass spectrum of the theory is determined by the zeroes of
Bessel functions, and the agreement with large N lattice data is excellent.Comment: 4 page letter; version to appear in Physical Review Letter
Transient Astrophysical Pulses and Quantum Gravity
Searches for transient astrophysical pulses could open an exciting new window
into the fundamental physics of quantum gravity. In particular, an evaporating
primordial black hole in the presence of an extra dimension can produce a
detectable transient pulse. Observations of such a phenomenon can in principle
explore the electroweak energy scale, indicating that astrophysical probes of
quantum gravity can successfully complement the exciting new physics expected
to be discovered in the near future at the Large Hadron Collider.Comment: 7 pages, This essay received an honorable mention in the Gravity
Research Foundation Essay Competition, 200
Concomitant multiple anomalies of renal vessels and collecting system
Although anomalies of renal vessels and collecting system are relatively frequent, their concomitant occurrence is a rare event. During dissection of a 75-year-old male formalin-embalmed cadaver, we found multiple variations in the renal vessels and renal collecting system. Both kidneys were normal in size and anteriorly malrotated, with duplex collecting system and duplex ureter. One ureter drained the upper part of the kidney and the second ureter drained the lower part of the kidney. Superior and inferior collecting systems were separated by renal parenchyma. The right kidney had two renal arteries, the first renal artery (main renal artery) originating from the abdominal aorta, passing behind the inferior vena cava (IVC) and entering the kidney through the superior and inferior renal hilum. The second artery was the inferior polar artery. In addition, the right kidney had two renal veins as well. Three renal tributaries emerged from the upper and lower portion of the right renal hilum, and they joined to form the main renal vein which drained into the IVC. The lower renal vein was the inferior polar vein. The left kidney had four renal arteries (two hilar arteries and two polar arteries). The main left renal vein emerged from both superior and inferior left renal hilum, passed in front of the abdominal aorta and drained into the IVC. The left kidney also had the inferior polar vein which was divided behind the aorta (retro aortic vein) into two venous trunks. These venous trunks drained separately into posteromedialaspect of the IVC. Finally, the right testicular vein was formed by two tributaries and drained into the IVC, whereas the two left testicular veins drained separately into the left main renal vein
Spacetime Emergence and General Covariance Transmutation
Spacetime emergence refers to the notion that classical spacetime "emerges"
as an approximate macroscopic entity from a non-spatio-temporal structure
present in a more complete theory of interacting fundamental constituents. In
this article, we propose a novel mechanism involving the "soldering" of
internal and external spaces for the emergence of spacetime and the twin
transmutation of general covariance. In the context of string theory, this
mechanism points to a critical four dimensional spacetime background.Comment: 11 pages, v2: version to appear in MPL
Aging and Holography
Aging phenomena are examples of `non-equilibrium criticality' and can be
exemplified by systems with Galilean and scaling symmetries but no time
translation invariance. We realize aging holographically using a deformation of
a non-relativistic version of gauge/gravity duality. Correlation functions of
scalar operators are computed using holographic real-time techniques, and agree
with field theory expectations. At least in this setup, general aging phenomena
are reproduced holographically by complexifying the bulk space-time geometry,
even in Lorentzian signature.Comment: 1 pdf figur
On the Nonperturbative Consistency of String Theory
An infinite number of distinct matrix models reproduce the perturbation
theory of string theory. Due to constraints of causality, however, we
argue that none of the existing constructions gives a consistent
nonperturbative definition of the string.Comment: 10 pages, 2 figures, LaTeX (author's name added
Fuzzy Gravitons From Uncertain Spacetime
The recently proposed remarkable mechanism explaining ``stringy exclusion
principle" on an Anti de Sitter space is shown to be another beautiful
manifestation of spacetime uncertainty principle in string theory as well as in
M theory. Put in another way, once it is realized that the graviton of a given
angular momentum is represented by a spherical brane, we deduce the maximal
angular momentum directly from either the relation
in M theory or \Delta t\Delta x>\ap in string theory. We also show that the
result of hep-th/0003075 is similar to results on D2-branes in SU(2) WZW model.
Using the dual D2-brane representation of a membrane, we obtain the
quantization condition for the size of the membrane.Comment: 10 pages, harvmac. v2: a ref. and a note added; v3: A remark and one
more ref. adde
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