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Inflation

As continuation for the  Cyclic Universe  and  earlier  blogs I continue a bit deeper what happened in very beginning of the Universe. Modern cosmology suggests that the early universe may have been driven by a remarkable process known as cosmic inflation — a brief era of exponential expansion that occurred fractions of a second after the beginning of time. The standard explanation in most inflation models is that a hypothetical field filled space with a very large vacuum-like energy density. While the field slowly evolved, its energy acted like a repulsive gravitational source, causing spacetime to expand exponentially, exceeding the speed of light. Generally, the particle that manifests the field is called as inflaton. In the end of inflation the field became unstable and decayed to hot plasma of standard model particles that is called as reheating of the universe.  This marked the true beginning of the  Hot Big Bang  phase. Some researchers pr...

Cyclic Universe

A few years ago I wrote in the blog  how the universe may have have originated.  Many scientists believe there was no singularity in the beginning in the form of infinite density. CMB and gravitational wave observations indicate that the h ottest phase of the hot Big Bang, was not more than about ~ 10 28   K or ~ 10 15  GeV in terms of energy. That places a cutoff on how far you can extrapolate the hot Big Bang backwards: to a time of ~ 10 -35  seconds and a size of ~1.5 meter for the observable universe. The inflation theory states that before that there were no particles (and thus no such heat), but all energy was embedded in the inflation field.  Einstein was considering that singularities derived from the general relativity were more like mathematical artefacts, not presenting a realistic nature such as the center of the black hole. He tried to augment quantum effects into the theory and proposed that an Einstein–Rosen bridge arises from the center...

Emergent time

In the blog I wrote a hypothesis about time, while not being a fundamental physical property, it rather  emerges from the rate of change.  Let me rephrase it in a more formal, physics-like language: “Let spacetime consist of three familiar spatial dimensions and a fourth, less-accessible degree of freedom, usually associated with time but actually a dynamic distribution axis for quantum states. Elementary particles are not confined purely to 3-space; their wavefunctions distribute partially into this fourth dimension. Near massive energy concentrations (e.g., black holes), this distribution favors the fourth dimension, effectively reducing observable spatial activity — explaining time dilation and event horizon behavior. Gravitation itself emerges from the gradient of rate of change , driven by the local geometry of wavefunction distribution along this fourth axis.” This is speculative, yes, but  logically coherent , and it: Respects much of existing physics. Offers n...

The countdown to the beginning

The question where we've all come from has been fascinating for the ages. Quite many of us have heard the scientific explanation of the Big Bang that gave the birth for the universe. Georges Lemaître, a Belgian cosmologist and Catholic priest, introduced Big Bang in his scientific paper in 1931, stating that the observable universe began at a definite point in time. Edwin Hubble had confirmed through analysis of galactic redshifts in 1929 that galaxies are drifting apart. Thus expanding universe could be traced back in time to an originating single point that is actually approximated to be happened nearly 13,8 billion years ago. There were different theories of the steady-state universe still in the following decades till 1964 when the Cosmic Microwave Background (CMB) was  discovered,  that had been a prediction of the Big Bang theory. The CMB is an uniform background radiation throughout the universe caused by the high temperatures and densities in the distant past. Act...

On a rubber mat

In the classical physics Newton's laws of gravitation explained gravity as a fundamental attractive force between any objects having mass. According to a legend Isaac Newton realized that there must be a force when an apple dropped from a tree. Around 1687 he presented that the force behaves same way between the Earth and moon or Earth and any object. Later the mathematical presentation of the gravitational force was determined as it's strength was proportional to the masses and inversely to the their distance square. Additionally, to make equation to work in the standard units a multiplier called gravitational constant was needed. By1862 James Clerk Maxwell described that electric and magnetic fields are generated by charges and currents. Analogously, Gauss's law for gravity presented gravity as a field caused by mass according to Newton's law in the classical physics.  In the early 20th century the modern physics changed our understanding of the reality.  The theory o...