European Union Between the Big Bang and the Big Crunch

Author(s):  
Vicenç Fernández Alarcón ◽  
Shahrazad Hadad ◽  
Simona Irina Goia
2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Günter Scharf ◽  

We continue the recent study of our model theory of low-density cosmology without dark matter. We assume a purely radiative spherically symmetric background and treat matter as anisotropic perturbations. Einstein’s equations for the background are solved numerically. We find two irregular singular points, one is the Big Bang and the other a Big Crunch. The radiation temperature continues to decrease for another 0.21 Hubble times and then starts to increase towards infinity. Then we derive the four evolution equations for the anisotropic perturbations. In the Regge- Wheeler gauge there are three metric perturbations and a radial velocity perturbation. The solution of these equations allow a detailed discussion of the cosmic evolution of the model universe under study.


2009 ◽  
Vol 18 (14) ◽  
pp. 2257-2263 ◽  
Author(s):  
VISHNU JEJJALA ◽  
MICHAEL KAVIC ◽  
DJORDJE MINIC ◽  
CHIA-HSIUNG TZE

We present a novel solution to the nature and formation of the initial state of the Universe. It derives from the physics of a generally covariant extension of matrix theory. We focus on the dynamical state space of this background-independent quantum theory of gravity and matter — an infinite-dimensional, complex, nonlinear Grassmannian. When this space is endowed with a Fubini–Study-like metric, the associated geodesic distance between any two of its points is zero. This striking mathematical result translates into a physical description of a hot, zero-entropy Big Bang. The latter is then seen as a far-from-equilibrium, large-fluctuation-driven, metastable ordered transition — a "freezing by heating" jamming transition. Moreover, the subsequent unjamming transition could provide a mechanism for inflation while rejamming may model a Big Crunch, the final state of gravitational collapse.


2018 ◽  
Vol 51 (2) ◽  
pp. 505-513 ◽  
Author(s):  
Angela Altomare ◽  
Nicola Corriero ◽  
Corrado Cuocci ◽  
Aurelia Falcicchio ◽  
Anna Moliterni ◽  
...  

The hybrid big bang–big crunch algorithm is a combination of a global optimization algorithm inspired by one of the theories of the evolution of the universe, named the big bang and big crunch theory, and the simulated annealing method. The procedure was implemented in the latest version of the programEXPOand applied to crystal-structure solution from powder diffraction data. Several aspects of the hybrid big bang–big crunch algorithm can be further optimized with the aim of obtaining good quality solutions in a shorter computation time. In the present study, the hybrid big bang–big crunch procedure has been combined with the greedy randomized adaptive search procedure (GRASP) and some steps of the algorithm have been improved. The new approach, implemented in theEXPOpackage, has been successfully tested on numerous known crystal structures.


Algorithms ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 146 ◽  
Author(s):  
Abdoalnasir Almabrok ◽  
Mihalis Psarakis ◽  
Anastasios Dounis

This article presents a novel technique for the fast tuning of the parameters of the proportional–integral–derivative (PID) controller of a second-order heat, ventilation, and air conditioning (HVAC) system. The HVAC systems vary greatly in size, control functions and the amount of consumed energy. The optimal design and power efficiency of an HVAC system depend on how fast the integrated controller, e.g., PID controller, is adapted in the changes of the environmental conditions. In this paper, to achieve high tuning speed, we rely on a fast convergence evolution algorithm, called Big Bang–Big Crunch (BB–BC). The BB–BC algorithm is implemented, along with the PID controller, in an FPGA device, in order to further accelerate of the optimization process. The FPGA-in-the-loop (FIL) technique is used to connect the FPGA board (i.e., the PID and BB–BC subsystems) with the plant (i.e., MATLAB/Simulink models of HVAC) in order to emulate and evaluate the entire system. The experimental results demonstrate the efficiency of the proposed technique in terms of optimization accuracy and convergence speed compared with other optimization approaches for the tuning of the PID parameters: sw implementation of the BB–BC, genetic algorithm (GA), and particle swarm optimization (PSO).


LOGOS ◽  
2020 ◽  
Vol 17 (2) ◽  
pp. 15-45
Author(s):  
Leo Agung Srie Gunawan

The problem of the universe having a great mystery encloses the big question about its origin. To answer the origin of universe, generally, there are two approaches, namely faith and science. The main question has to be replied: “What do the differences and the similarity of them?” The approach of faith bases on the inquiry of “who causes the existence of the universe”. This approach states that the origin of universe was created by God and hence, it was formed by God from a nothingness (creatio ex nihilo). This is known as the theorem of creation. Furthermore, the scientific approach is grounded on the research of “how the universe was formed in the beginning”. This oncoming being explained by the Big Bang Theory, which is continued by the Big Crunch Theory, asserts that the origin of universe came from the prime matter which exploded incredibly in a such a way that the formation process of the universe took place (the singularity). This is well-known as the theory of evolution (the cosmological evolution). In conclusion, the scientific approach explaining the process of creation and the faith one answering the actor of it are complementary.


2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Alex Kehagias ◽  
Hervé Partouche ◽  
Nicolaos Toumbas

Abstract We determine the inner product on the Hilbert space of wavefunctions of the universe by imposing the Hermiticity of the quantum Hamiltonian in the context of the minisuperspace model. The corresponding quantum probability density reproduces successfully the classical probability distribution in the ħ → 0 limit, for closed universes filled with a perfect fluid of index w. When −1/3 < w ≤ 1, the wavefunction is normalizable and the quantum probability density becomes vanishingly small at the big bang/big crunch singularities, at least at the semiclassical level. Quantum expectation values of physical geometrical quantities, which diverge classically at the singularities, are shown to be finite.


2015 ◽  
Vol 725-726 ◽  
pp. 1544-1551 ◽  
Author(s):  
Aleksandar Milajić ◽  
Dejan Beljaković ◽  
Nikola Čulić ◽  
Nikolay Vatin ◽  
Vera Murgul

Optimal design of an energy efficient building has to meet two confronted demands: to minimize total cost of construction, and to minimize environmental impact and energy consumption, which is usually obtained by the implementation of expensive insulation materials and equipment. Therefore, optimization task cannot be formulated by a single objective function, but requires at least two functions. Consequently, there is no unique, i.e. the best solution, but a number of more or less acceptable ones among which designer chooses a satisfying one considering given demands and limitations. This paper presents methodology for using the Big Bang – Big Crunch algorithm for optimum design of an energy efficient building that would meet two confronted demands – the lowest price and the lowest environmental impact during the 25 years period. Presented study showed that this approach provides several acceptable solutions among which the decision maker can make a choice in accordance with his/her needs and wishes.


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