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Monday, August 10, 2015

The Structure of the Universe :Challenge to the Plasma Theory (Part-I)

   Author : Rumana Reza    




An empty cup could be poured by knowledge,otherwise nothing new could be injected there . So, let's start from 0/nil .......


- Particles of matter
- >Atoms
- >Molecules
-> Macromolecules
-> Cell organelles
-> Cells
-> Tissues
->Organs
-> Systems
-> Organisms
-> Populations
-> Ecosystems
-> Biomes
-> Planets
-> Planetary Systems with Stars
->Galaxies
->The Universe
->Infinity  


Here we will focus on those things only which are relevant to understand the structural system of this universe. 


States of  Matter





Literature Review 


Atom


Atoms are building blocks. To build molecules, we will need atoms of different elements. Atoms are the general term used to describe pieces of matter. We have billions of billions of atoms in our body. However, we may only find about 40 elements - billions of hydrogen (H) atoms, billions of oxygen (O) atoms, and a bunch of others. All of the atoms are made of the same basic pieces, but they are organized in different ways to make unique elements. While the atoms have different masses and organization for each element, they are all built with the same parts. Electrons, protons, and neutrons make the Universe the way it is. 

Bohr model

In 1913 the physicist Niels Bohr proposed a model in which the electrons of an atom were assumed to orbit the nucleus but could only do so in a finite set of orbits, and could jump between these orbits only in discrete changes of energy corresponding to absorption or radiation of a photon.

Later in the same year Henry Moseley provided additional experimental evidence in favor of Niels Bohr's theory. These results refined Ernest Rutherford's and Antonius Van den Broek's model, which proposed that the atom contains in its nucleus a number of positive nuclear charges that is equal to its (atomic) number in the periodic table. Until these experiments, atomic number was not known to be a physical and experimental quantity. That it is equal to the atomic nuclear charge remains the accepted atomic model today.
The Bohr model of the atom, with an electron making instantaneous quantum leaps from one orbit to another. This model is obsolete : Kurzon - Own work

Chemical bonding :


Chemical bonds between atoms were  explained as the interactions between their constituent electrons. As the chemical properties of the elements were known to largely repeat themselves according to the periodic law, in 1919 the American chemist Irving Langmuir suggested that this could be explained if the electrons in an atom were connected or clustered in some manner. Groups of electrons were thought to occupy a set of electron shells about the nucleus.

Atomic orbital


An atomic orbital is a mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom. This function can be used to calculate the probability of finding any electron of an atom in any specific region around the atom's nucleus. The term may also refer to the physical region or space where the electron can be calculated to be present, as defined by the particular mathematical form of the orbital.





                                                     s-type modes



Mode u_{01} (1s orbital)

Mode u_{02} (2s orbital)

Mode u_{03} (3s orbital)



*********************************************************************





Mode u_{11} (2p orbital)
           p-type modes


                                                                    
Mode u_{12} (3p orbital)
Mode u_{13} (4p orbital)





*********************************************************************************

                                                                  d-type modes
Mode u_{21} (3d orbital)
Mode u_{22} (4d orbital)



     



Mode u_{23} (5d orbital)


Quantum State


In quantum physicsquantum state refers to the state of a quantum system.A quantum state can be either pure or mixed. A pure quantum state is represented by a vector, called a state vector, in a Hilbert space. For example, when dealing with the energy spectrum of the electron in a hydrogen atom, the relevant state vectors are identified by the principal quantum number, written  . For a more complicated case, consider Bohm's formulation of the EPR experiment, where the state vector

involves superposition of joint spin states for two particles. Mathematically, a pure quantum state is represented by a state vector in a Hilbert space over complex numbers, which is a generalization of our more usual three-dimensional space. If this Hilbert space is represented as a function space, then its elements are called wave functions.
A mixed quantum state corresponds to a probabilistic mixture of pure states; however, different distributions of pure states can generate equivalent (i.e., physically indistinguishable) mixed states. Mixed states are described by so-called density matrices. A pure state can also be recast as a density matrix; in this way, pure states can be represented as a subset of the more general mixed states.
For example, if the spin of an electron is measured in any direction, e.g. with a Stern–Gerlach experiment, there are two possible results: up or down. The Hilbert space for the electron's spin is therefore two-dimensional. A pure state here is represented by a two-dimensional complex vector , with a length of one; that is, with
where  andare the absolute values of   and   .A mixed state, in this case, is a 2 X 2 matrix that is Hermitianpositive-definite, and has trace 1.

Before a particular measurement is performed on a quantum system, the theory usually gives only a probability distribution for the outcome, and the form that this distribution takes is completely determined by the quantum state and the observable describing the measurement. These probability distributions arise for both mixed states and pure states: it is impossible in quantum mechanics (unlike classical mechanics) to prepare a state in which all properties of the system are fixed and certain. This is exemplified by the uncertainty principle, and reflects a core difference between classical and quantum physics. Even in quantum theory, however, for every observable there are some states that have an exact and determined value for that observable.



Probability densities for the electron of a hydrogen atom in different quantum states.References: Forinash, Kyle.
(Source: wiki )




To Be Continued........

Copyright © 2015 by Rumana Reza (Aurny)






                                                          




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