The Lyα clouds as tracers of the evolution of the universe

2007 ◽  
pp. 22-41
Author(s):  
Jose Luis Sanz
Keyword(s):  
Evolution Of The Universe ◽  
The Universe

PHILOSOPHY AND THE MEANING OF LIFE

Think ◽  
2021 ◽  
Vol 21 (60) ◽  
pp. 33-49
Author(s):  
William Lyons
Keyword(s):  
Human Life ◽  
Meaning Of Life ◽  
Point Of View ◽  
Eternal Life ◽  
Evolution Of The Universe ◽  
Life On Earth ◽  
The Universe

The author sets out to respond to the student complaint that ‘Philosophy did not answer “the big questions”’, in particular the question ‘What is the meaning of life?’ The response first outlines and evaluates the most common religious answer, that human life is given a meaning by God who created us and informs us that this life is just the pilgrim way to the next eternal life in heaven. He then discusses the response that, from the point of view of post-Darwinian science and the evolution of the universe and all that is in it, human life on Earth must be afforded no more meaning than the meaning we would give to a microscopic planaria or to some creature on another planet in a distant universe. All things including human creatures on Planet Earth just exist for a time and that is that. There is no plan or purpose. In the last sections the author outlines the view that it is we humans ourselves who give meaning to our lives by our choices of values or things that are worth pursuing and through our resulting sense of achievement or the opposite. Nevertheless the question ‘What is the meaning of life?’ can mean quite different things in different contexts, and so merit different if related answers. From one point of view one answer may lie in terms of the love of one human for another.

Evolution of the universe from the perspective of entropy and information

2021 ◽  
pp. 2150111
Author(s):  
Fei-Quan Tu ◽  
Bin Sun ◽  
Meng Wan ◽  
Qi-Hong Huang
Keyword(s):  
Information Entropy ◽  
Second Law Of Thermodynamics ◽  
Boltzmann Entropy ◽  
Evolution Of The Universe ◽  
Thermodynamic Entropy ◽  
Entire Universe ◽  
Low Entropy ◽  
The Relationship ◽  
The Universe ◽  
Entropy Of The Universe

Entropy is a key concept widely used in physics and other fields. At the same time, the meaning of entropy with different names and the relationship among them are confusing. In this paper, we discuss the relationship among the Clausius entropy, Boltzmann entropy and information entropy and further show that the three kinds of entropy are equivalent to each other to some extent. Moreover, we point out that the evolution of the universe is a process of entropy increment and life originates from the original low entropy of the universe. Finally, we discuss the evolution of the entire universe composed of the cosmological horizon and the space surrounded by it and interpret the entropy as a measure of information of all microstates corresponding to a certain macrostate. Under this explanation, the thermodynamic entropy and information entropy are unified and we can conclude that the sum of the entropy of horizon and the entropy of matter in the space surrounded by the horizon does not decrease with time if the second law of thermodynamics holds for the entire universe.

scholarly journals From Quantum Unstable Systems to the Decaying Dark Energy: Cosmological Implications

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Aleksander Stachowski ◽  
Marek Szydłowski ◽  
Krzysztof Urbanowski
Keyword(s):  
Dark Energy ◽  
Time Reversal ◽  
Hubble Parameter ◽  
Decay Process ◽  
Time Dependent ◽  
Time Reversal Symmetry ◽  
Exponential Form ◽  
Cosmological Time ◽  
Evolution Of The Universe ◽  
The Universe

We consider a cosmology with decaying metastable dark energy and assume that a decay process of this metastable dark energy is a quantum decay process. Such an assumption implies among others that the evolution of the Universe is irreversible and violates the time reversal symmetry. We show that if we replace the cosmological time t appearing in the equation describing the evolution of the Universe by the Hubble cosmological scale time, then we obtain time dependent Λ(t) in the form of the series of even powers of the Hubble parameter H: Λ(t)=Λ(H). Our special attention is focused on radioactive-like exponential form of the decay process of the dark energy and on the consequences of this type decay.

scholarly journals Self-organizing Systems in the Light of the Arrows of Orderedness, Symmetry, and Entropy

1970 ◽  
Vol 2 (2) ◽  
pp. 63-73
Author(s):  
György Darvas
Keyword(s):  
Second Law Of Thermodynamics ◽  
Local Symmetry ◽  
Evolution Of The Universe ◽  
Global Evolution ◽  
New Material ◽  
New Interpretation ◽  
The One ◽  
Global And Local ◽  
The Universe ◽  
Matter Energy

The paper makes an attempt to resolve two conceptual mingling: (a) the mingling of the two interpretations of the concept of orderedness applied in statistical thermodynamics and in symmetrology, and (b) the mingling of two interpretations of evolution applied in global and local processes. In conclusion, it formulates a new interpretation on the relation of the emergence of new material qualities in selforganizing processes on the one hand, and the evolution of the universe, on the other. The process of evolution is a sequence of emergence of new material qualities by self-organization processes, which happen in negligible small segments of the universe. Although thermodynamics looks at the universe as a closed (isolated) system, this holds for its outside boundaries only, while the universe has many subsystems inside, which are not isolated (closed), since they are in a permanent exchange of matter, energy, etc. with their environment (with the rest of the universe) through their open boundaries. Any ";;emergence";; takes place, i.e., all new qualities come into being just in these small open segments of the universe. The conditions to apply the second law of thermodynamics are not present here. Therefore, global evolution of the universe is the consequence of local symmetry decreases, local decreases of orderedness, and possible local decreases of entropy.

scholarly journals ON POSSIBLE GEOMETRIC AND ASTROPHYSICAL EFFECTS OF NONLINEAR SPINOR FIELDS IN THE MEGAMIR, MACROWORLD AND MICROWORLD

Metaphysics ◽  
2020 ◽  
pp. 82-93
Author(s):  
V. G Krechet
Keyword(s):  
General Relativity ◽  
Gravitational Interaction ◽  
Space Time ◽  
Elementary Particles ◽  
Nonlinear Spinor ◽  
Evolution Of The Universe ◽  
Spinor Fields ◽  
Astrophysical Objects ◽  
Local Space ◽  
The Universe

In this article, within the framework of general relativity, the possible effect of the gravitational interaction of Dirac nonlinear spinor fields on the evolution of the Universe, on the formation of astrophysical objects and on the formation of the geometry of the local space-time of elementary particles with spin ħ / 2 is considered.

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