Time development of the free-quark-to-baryon ratio from the very early universe

1982 ◽  
Vol 33 (16) ◽  
pp. 529-534
Author(s):  
Suk Koo Yun
Keyword(s):  
Early Universe ◽  
Time Development ◽  
Free Quark

The early universe

1989 ◽  
Vol 159 (10) ◽  
pp. 393
Author(s):  
Ya.A. Smorodinskii
Keyword(s):  
Early Universe

Photo-Current Enhancement at Cu/p-Cu2O/rGO- Electrolyte Interface

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
S.P.A.U.K. Samarakoon ◽  
C.A.N. Fernando
Keyword(s):  
Diffuse Reflectance ◽  
Electrochemical Cell ◽  
Time Development ◽  
Charge Carriers ◽  
Electrochemical Cells ◽  
Current Action ◽  
Electrolyte Interface ◽  
Reduced Graphene ◽  
Efficient Charge ◽  
Photo Current

A considerable photo-current enhancement was found at the Cu/p-Cu2O/rGO-electrolyte interface in a photo-electrochemical cell with compared to that of Cu/p-Cu2O-electrolyte interface. The reason for the photo-current enhancement may be due to the efficient charge separation process provided at Cu/p-Cu2O/rGO-electrolyte interface. Here rGO (reduced graphene oxide) acts as an electron acceptor for the photo-generated charge carriers as it readily accept electrons from the conduction band of p-Cu2O. rGO was synthesized using electro-phoretic deposition (EPD) technique. Fabricated samples were characterized using diffuse reflectance spectra, photo-current action spectra and the time development of the photocurrent of photo-electrochemical cells.

scholarly journals VIBRATIONAL LEVEL POPULATION OF H 2 AND H + 2 IN THE EARLY UNIVERSE

2011 ◽  
Vol 193 (1) ◽  
pp. 7 ◽  
Author(s):  
Carla M. Coppola ◽  
Savino Longo ◽  
Mario Capitelli ◽  
Francesco Palla ◽  
Daniele Galli
Keyword(s):  
Early Universe ◽  
Vibrational Level ◽  
Level Population

scholarly journals IMPLICATIONS OF A QUANTUM MECHANICAL TREATMENT OF THE UNIVERSE

1998 ◽  
Vol 13 (05) ◽  
pp. 347-351 ◽  
Author(s):  
MURAT ÖZER
Keyword(s):  
Quantum Mechanics ◽  
Wave Packet ◽  
Early Universe ◽  
Mechanical Treatment ◽  
Correspondence Principle ◽  
Scale Factor ◽  
Quantum Mechanical ◽  
Quantum Mechanical Treatment ◽  
The Standard Model ◽  
The Universe

We attempt to treat the very early Universe according to quantum mechanics. Identifying the scale factor of the Universe with the width of the wave packet associated with it, we show that there cannot be an initial singularity and that the Universe expands. Invoking the correspondence principle, we obtain the scale factor of the Universe and demonstrate that the causality problem of the standard model is solved.

scholarly journals The Topological Origin of Quantum Randomness

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 581
Author(s):  
Stefan Heusler ◽  
Paul Schlummer ◽  
Malte S. Ubben
Keyword(s):  
High School ◽  
Hilbert Space ◽  
Group Theory ◽  
Lorentz Group ◽  
Quantum Physics ◽  
Time Development ◽  
Mathematical Structures ◽  
Stochastic Nature ◽  
Quantum Randomness ◽  
And Topology

What is the origin of quantum randomness? Why does the deterministic, unitary time development in Hilbert space (the ‘4π-realm’) lead to a probabilistic behaviour of observables in space-time (the ‘2π-realm’)? We propose a simple topological model for quantum randomness. Following Kauffmann, we elaborate the mathematical structures that follow from a distinction(A,B) using group theory and topology. Crucially, the 2:1-mapping from SL(2,C) to the Lorentz group SO(3,1) turns out to be responsible for the stochastic nature of observables in quantum physics, as this 2:1-mapping breaks down during interactions. Entanglement leads to a change of topology, such that a distinction between A and B becomes impossible. In this sense, entanglement is the counterpart of a distinction (A,B). While the mathematical formalism involved in our argument based on virtual Dehn twists and torus splitting is non-trivial, the resulting haptic model is so simple that we think it might be suitable for undergraduate courses and maybe even for High school classes.

scholarly journals Electroweak axion string and superconductivity

2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Yoshihiko Abe ◽  
Yu Hamada ◽  
Koichi Yoshioka
Keyword(s):  
Electric Current ◽  
Early Universe ◽  
Parameter Space ◽  
Cosmic String ◽  
Topological Charge ◽  
Attractive Force ◽  
Electroweak Scale ◽  
Large Current

Abstract We study the axion strings with the electroweak gauge flux in the DFSZ axion model and show that these strings, called the electroweak axion strings, can exhibit superconductivity without fermionic zeromodes. We construct three types of electroweak axion string solutions. Among them, the string with W-flux can be lightest in some parameter space, which leads to a stable superconducting cosmic string. We also show that a large electric current can flow along the string due to the Peccei-Quinn scale much higher than the electroweak scale. This large current induces a net attractive force between the axion strings with the same topological charge, which opens a novel possibility that the axion strings form Y-junctions in the early universe.

scholarly journals Dark matter freeze-in from semi-production

2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Andrzej Hryczuk ◽  
Maxim Laletin
Keyword(s):  
Dark Matter ◽  
Early Universe ◽  
Cross Section ◽  
Thermal Equilibrium ◽  
Indirect Detection ◽  
Production Mechanism ◽  
Number Density ◽  
Matter Production ◽  
Relic Density ◽  
Standard Formalism

Abstract We study a novel dark matter production mechanism based on the freeze-in through semi-production, i.e. the inverse semi-annihilation processes. A peculiar feature of this scenario is that the production rate is suppressed by a small initial abundance of dark matter and consequently creating the observed abundance requires much larger coupling values than for the usual freeze-in. We provide a concrete example model exhibiting such production mechanism and study it in detail, extending the standard formalism to include the evolution of dark matter temperature alongside its number density and discuss the importance of this improved treatment. Finally, we confront the relic density constraint with the limits and prospects for the dark matter indirect detection searches. We show that, even if it was never in full thermal equilibrium in the early Universe, dark matter could, nevertheless, have strong enough present-day annihilation cross section to lead to observable signals.

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