|AstroNuclPhysics ® Nuclear Physics - Astrophysics - Cosmology - Philosophy||Gravity, black holes and physics|
GRAVITATION AND THE GLOBAL STRUCTURE OF THE UNIVERSE:
5.1. Basic starting points and principles of cosmology
5.2. Einstein's and deSitter's universe. Cosmological constant.
5.3. Fridman's dynamic models of the universe
5.4. Standard cosmological model. Big Bang.
5.5. Microphysics and cosmology. Inflationary universe.
5.6. The future of the universe
5.7. Anthropic principle and existence of multiple universes
5.8. Cosmology and physics
5.8. Cosmology and physics
Is a pleasure to acknowledge, that contemporary relativistic cosmology has already emerged from the stage of unfounded speculations and idle theorizing and has become an important part of physics. Can give a consistent picture of the structure and evolution of the universe as a whole; this picture is built on the proven laws of physics and its predictions agree well with the observation . Let us therefore consider some general aspects of the relationship between cosmology and physics.
The methodology of physical cognition consists of three main elements: observation , experiment and theory . In the early stages of the development of physics, the first of these methods - observation - played a decisive role; let us recall only Newton's law of gravitation based on astronomically observed Kepler's laws of planetary motion. However, Newton was already doing mechanical experiments that resulted in his three basic laws of motion. With the further development of physics, accompanied by a profound improvement in experimental techniques, the role of observation declined rapidly. Especially since the early 20th century, when for the reveal the laws of the microstructure of matter, it was necessary to use more and more sophisticated and costly experiments (eg powerful yet accurate accelerators in conjunction with subtle detection electronics), the method of observation seemed already entirely historic and the relationship between physics and astronomy is one-way : physics in its laboratories reveals the fundamental laws of nature that allow to explain and predict astronomically observed phenomena in space.
Fig.5.12. A wide range of sizes of objects in our world, explored by various fields of physics and natural sciences using various tools.
(it is discussed in more detail in §1.0 " Physics - fundamental natural science ", passage " Methods and tools of nature research ", monograph " Nuclear physics and ionizing radiation physics ")
In recent years, however, this relationship has begun to
change. Indeed, contemporary relativistic cosmology has shown
that the universe, in its very hot and dense initial phase, was a
kind of unique "laboratory" of high-energy physics , in which the processes we are
now trying most closely to observe on massive accelerators and
even those phenomena whose laboratory implementation there is no
hope for the foreseeable future. The cosmological consequences of
current theories of elementary
(especially unitary theories) have proven to be so clear and obvious
that their confrontation with astronomical
observations distant universe *) makes it possible to
set strong constraints on the parameters of these theories of
elementary particles, and sometimes even their verification or
*) In addition to optical observations (including spectroscopic) with increasingly larger and more powerful telescopes and radio telescopic observations using large antenna systems (interconnected), it is primarily a detailed measurement of the properties of microwave relic radiation - its homogeneity, fluctuations (depending on the angular distance and wavelength), polarization. Already at the time of the separation of radiation from matter, there were nuclei of future structures in the universe, so these photons passed through places with different gravitational potentials, which led to small changes in their energy and wavelength - a slight cooling or heating. These fluctuations should be visible even now, as slightly warmer and colder "spots" in the otherwise isotropic distribution of relic radiation - they represent a kind of "paleontological imprint" of the structures of the early universe - see §5.4, part "Microwave relic radiation - a messenger of early space news". The temperature difference is very small, of the order of 10 -5 degrees, so the relevant methods of their data measurement are constantly being improved *). In the future, the detection of primordial gravitational waves (see §2.7 "Gravitational waves", passage "Detection of gravitational waves "), or detection of relict neutrinos (for details on neutrinos and their detection, see eg the passage" neutrino "in §1.2" Radioactivity "of the book" Nuclear Physics and Physics of Ionizing Radiation ").
*) For a detailed study of relic radiation, the COBE satellite (Cosmic Background Explorer) was launched in 1989 and in 2001 WMAP satellite (Wilkinson Microwave Anisotropy Probe), in 2007, an even more sensitive PLANCK probe was launched.
At first glance, it might seem that nuclear and
particle physics, dealing with the smallest known particles of
matter, has very little to do with cosmology, which, on the other
hand, examines the largest possible objects in the universe.
However, current research refutes this view. Both in the form of
elementary particles and in cosmology, it was possible to develop
so-called standard models , which explain very
well the results of almost all physical experiments and
astronomical observations. On the other hand, they raise new
questions and problems - how to "get things
At present, in the mutual interest of physics and cosmology are the fundamental principles of our world. In cosmology, these are questions of the origin of our universe, the basic laws which control him, his ultimate destiny . In particle physics, these are questions of the nature of matter : how did matter originate ?; what is its structure - what are its basic building "stones" and how do these interact ?; What are the mechanisms of these building blocks that create such complex objects as galaxies, stars, planets - and ultimately living matter? This creates a very remarkable connection between the microworld and the megaworld...
All the most basic aspects of matter and the universe seem to originate in those first minute fractions of a second after the Big Bang, when the properties of the physical interactions themselves were formed. The laws of physics that prevailed in these extreme conditions are not yet well known - we do not know what the structure of space and time was then, what was the number of dimensions, how matter was formed. At that time, the macroworld and the cosmos, then non-existent in the present sense, intertwined with the microworld of quantum laws (cf. also the passage " Very Early Universe " in §5.4 ) . Some aspects of these phenomena may never be clarified..?..
However, some current (and especially future) concepts of unitary theories of fields , interactions and elementary particles (mentioned in Appendix B, especially in §B.6 " Unification of fundamental interactions. Supergravity. Superstrings. ") , in co-production , could shed some light here with experiments of high-energy particle interactions on successively built large accelerators (see " Charged particle accelerators ") . The finer the details of the structure of matter we want to penetrate - and thus also the greater the depth of knowledge of the structure of the universe - the higher the energy of the particles we must use. It can be said that high-energy particles are certain "probes" into the deepest details of the structure of matter and at the same time into the earliest moments of the evolution of the universe.
Two seemingly very remote parts of physics - the theory of elementary particles examining the smallest objects and cosmology examining the largest of the whole universe - thus combine to form a unified picture of the world . The successes of research in one area can be very penetrating in the other area of knowledge. It is this dialectical unity of the microworld, macroworld and megaworld that is the characteristic trend in contemporary fundamental physics.
Physically, we humans are just a tiny powder in the universe. Spiritually, however, we go far beyond this insignificance : we are able to know and understand the vast universe - its structure, its functioning, its evolution ...
|5.7. Anthropic principle and the existence of multiple universes
and general theory of relativity
|Gravity, black holes and space-time physics :|
|Gravity in physics||General theory of relativity||Geometry and topology|
|Black holes||Relativistic cosmology||Unitary field theory|
|Anthropic principle or cosmic God|
|Nuclear physics and physics of ionizing radiation|
|AstroNuclPhysics ® Nuclear Physics - Astrophysics - Cosmology - Philosophy|