60,814 research outputs found
Conceptual unification of elementary particles, black holes, quantum de Sitter and Anti de Sitter string states
We provide a conceptual unified description of the quantum properties of
black holes (BH), elementary particles, de Sitter (dS) and Anti de Sitter (AdS)
string states.The conducting line of argument is the classical-quantum (de
Broglie, Compton) duality here extended to the quantum gravity (string) regime
(wave-particle-string duality). The semiclassical (QFT) and quantum (string)
gravity regimes are respectively characterized and related: sizes, masses,
accelerations and temperatures. The Hawking temperature, elementary particle
and string temperatures are shown to be the same concept in different energy
regimes and turn out the precise classical-quantum duals of each other;
similarly, this result holds for the BH decay rate, heavy particle and string
decay rates; BH evaporation ends as quantum string decay into pure (non mixed)
radiation. Microscopic density of states and entropies in the two
(semiclassical and quantum) gravity regimes are derived and related, an
unifying formula for BH, dS and AdS states is provided in the two regimes. A
string phase transition towards the dS string temperature (which is shown to be
the precise quantum dual of the semiclassical (Hawking-Gibbons) dS temperature)
is found and characterized; such phase transition does not occurs in AdS alone.
High string masses (temperatures) show a further (square root temperature
behaviour) sector in AdS. From the string mass spectrum and string density of
states in curved backgrounds, quantum properties of the backgrounds themselves
are extracted and the quantum mass spectrum of BH, dS and AdS radii obtained.Comment: New original material; one minor misprint in eq.(1.3) correcte
Classical and Quantum Strings in plane waves, shock waves and spacetime singularities: synthesis and new results
Key issues of classical and quantum strings in gravitational plane waves,
shock waves and spacetime singularities are synthetically understood. This
includes the string mass and mode number excitations, energy-momentum tensor,
scattering amplitudes, vaccum polarization and wave-string polarization effect.
The role of the real pole singularities characteristic of the tree level string
spectrum (real mass resonances) and that of spacetime singularities is clearly
exhibited. This throws light on the issue of singularities in string theory
which can be thus classified and fully physically characterized in two
different sets: strong singularities (poles of order equal or larger than 2,
and black holes), where the string motion is collective and non oscillating in
time, outgoing and scattering states do not appear, the string does not cross
the singularities, and weak singularities (poles of order smaller than 2, Dirac
delta, and conic/orbifold singularities) where the whole string motion is
oscillatory in time, outgoing and scattering states exist, and the string
crosses the singularities. Commom features of strings in singular plane
backgrounds and in inflationary backgrounds are explicitly exhibited. The
string dynamics and the scattering/excitation through the singularities
(whatever their kind: strong or weak) is fully physically consistent and
meaningful.Comment: Synthesis and new material. 18 pages, no figure
Quantum Discrete Levels of the Universe from the Early Trans-Planckian Vacuum to the Late Dark Energy
The standard model of the universe is further completed back in time before
inflation in agreement with observations, classical-quantum gravity duality and
quantum space-time. Quantum vacuum energy bends the space-time and produces a
constant curvature de Sitter background. We link de Sitter universe and the
cosmological constant to the (classical and quantum) harmonic oscillator.
Quantum discrete cosmological levels are found: size, time, vacuum energy,
Hubble constant and gravitational (Gibbons-Hawking) entropy from the very early
trans-planckian vacuum to the classical today vacuum energy. For each level , the two: post and pre (trans)-planckian phases are covered: In
the post-planckian universe, the levels (in planck units) are: Hubble constant
, vacuum energy ,
entropy . As increases, radius, mass and increase,
and decrease and {\it consistently} the universe {\it
classicalizes}. In the pre-planckian (trans-planckian) phase, the quantum
levels are: , denoting quantum. The -levels cover {\it all} scales from
the far past highest excited trans-planckian level with finite
curvature, and minimum entropy ,
decreases till the planck level and enters the post-planckian phase
e.g: with the most
classical value , ,
. We implement the Snyder-Yang algebra in this context
yielding a consistent group-theory realization of quantum discrete de Sitter
space-time, classical-quantum gravity duality symmetry and a clarifying
unifying picture.(Abridged)Comment: Published version in Phys Rev D, 54 pages, 1 figure, new material.
arXiv admin note: text overlap with arXiv:1912.0665
Advances in String Theory in Curved Space Times
String Quantum Gravity is motivated and introduced. Advances in the study of
the classical and quantum string dynamics in curved spacetime are reported:
1-New Classes of Exact Multistring solutions in curved spacetimes. 2-Mass
spectrum of Strings in Curved Spacetimes. 3-The effect of a Cosmological
Constant and of Spacial Curvature on Classical and Quantum Strings. 4-Classical
splitting of Fundamental Strings. 5-The General String Evolution in constant
Curvature Spacetimes. 6-The Conformal Invariance Effects.Comment: Chalonge School Lectures on Astrofundamental Physics, 9th Course 7-18
September 2002, To appear in the Proceedings, NATO ASI Series edited by N.G.
Sanchez and Yu. Parijskij, Kluwer Pu
Toroidal and Klein bottle boundary slopes
Let M be a compact, connected, orientable, irreducible 3-manifold and T' an
incompressible torus boundary component of M such that the pair (M,T') is not
cabled. By a result of C. Gordon, if S and T are incompressible punctured tori
in M with boundary on T' and boundary slopes at distance d, then d is at most
8, and the cases where d=6,7,8 are very few and classified. We give a
simplified proof of this result (or rather, of its reduction process), based on
an improved estimate for the maximum possible number of mutually parallel
negative edges in the graphs of intersection of S and T. We also extend
Gordon's result by allowing either S or T to be an essential Klein bottle. to
the case where S or T is a punctured essential Klein bottle.Comment: Preliminary version, updated. We use a new approach that yields a
stronger conclusion. 28 pages, 18 figure
Effects of the magnetic dipole moment of charged vector mesons in their radiative decay distribution
We consider the effects of anomalous magnetic dipole moments of vector mesons
in the decay distribution of photons emitted in two-pseudoscalar decays of
charged vector mesons. By choosing a kinematical configuration appropriate to
isolate these effects from model-dependent and dominant bremsstrahlung
contributions, we show that this method can provide a valid alternative for a
measurement of the unknown magnetic dipole moments of charged vector mesons.Comment: Latex, 11 pages incl. 3 .ps figures, to appear in Phys. Rev.
- …