The Universe originated from an initial explosion that drove matter to expand from a state of severe condensation, according to the widely accepted Big Bang hypothesis. Still, there are some issues that the inflationary theory tries to solve.
What is The Inflationary Theory and why is it Helpful?
Some key issues remained unresolved in the Big Bang theory’s initial formulation. At the time of the explosion, the condition of the matter was such that conventional physical rules could not be applied.
The degree of uniformity found in the Universe was also difficult to explain since the Universe, according to this idea, would have grown too quickly to produce this uniformity.
The Big Bang theory states that the Universe’s expansion slows, but the inflationary theory states that it accelerates and causes the faster separation of certain items from others. This separation speed exceeds the speed of light without breaking the theory of relativity, which states that nobody of finite mass can move faster than the speed of light. The space around the items increases faster than light, yet the bodies stay still in relation to it.
The homogeneity of the observable cosmos is ascribed to this tremendous initial expansion speed; the parts that comprised it were so near each other that they shared the same density and temperature.
Alan H Guth, a physicist, and cosmologist at the Massachusetts Institute of Technology (M.I.T. ), proposed in 1981 that the hot Universe may grow exponentially at an intermediate stage.
The Inflationary Theory was born
Guth hypothesized that this inflationary process evolved when the primordial cosmos was in the unstable supercooled condition. This supercooled state is prevalent during phase transitions; for example, the water stays liquid below 0 degrees Celsius under proper circumstances. Supercooled water, of course, ultimately freezes; this occurs towards the conclusion of the inflationary phase.
In 1982 the Russian cosmologist Andrei Linde published the “new theory of the inflationary cosmos.” Linde observed that inflation emerges spontaneously in many fundamental particle theories, including the simplest models of scalar fields.
Suppose most physicists assume that the Universe was born all at once, boiling in the beginning and that the scalar field had minimal potential energy in the front. In that case, inflation appears natural and necessary rather than an exotic phenomenon invoked by theorists to solve their problems. It is a version that does not require quantum gravity phenomena, phase transitions, supercooling, or even beginning superheating.
Considering all possible types and values of scalar fields in the primordial Universe and attempting to determine whether any of them leads to inflation, it is discovered that in domains where inflation does not occur, they remain small. In contrast, in parts where inflation does appear, they become exponentially large and dominate the total volume of the Universe. Because scalar fields can have any value in the early Universe, Andrei Linde dubbed this concept “chaotic inflation.”
The Universe is Flat, according to the Inflationary Theory
Because the density of stuff in a flat universe is directly connected to its expansion velocity, the inflationary theory predicts that the world must be fundamentally flat, which can be scientifically proven.
The density disturbances created during inflation are another testable prediction of this theory. These are disturbances in the distribution of matter in the cosmos, and gravitational waves may accompany them. The troubles leave their imprint on the cosmic microwave background, which has filled the Universe for about 13.8 billion years.