Inflationary Universe Theory Explained


The creation of the universe continues to be one of the greatest mysteries of science. We may be able to peer into the clues from the initial development of our current reality, but how that reality began is still an unknown. Why the universe continues to exist is also a potential unknown.

One generally accepted theory regarding the creation of the universe is that it occurred with a “big bang.” The inflationary universe theory was developed in 1980 to help compliment this theory. That is because the idea of having a Big Bang comes with three very difficult problems which need to be solved.

The standard Big Bang theory lacks explanations for these issues.

  • Flatness. Current research indicates that the geometry of our universe is basically flat. Using the standard Big Bang theory, however, indicates that there should be a curvature which continues to grow over time.
  • Horizon. The universe as we know it is extremely vast. The opposite directions are so far apart, in fact, that light would not have enough time to travel the distance based on the current estimated age of the universe. This is even though the uniformity of cosmic background radiation suggests that these regions were once in contact with one another.
  • Monopoles. The standard Big Bang theory suggests that magnetic monopoles should have been created during the early days of the universe. These have never been observed, so if they do exist, then they are less common then the theory predicts them to be.

The inflationary universe theory works to solve these problems.

How Does the Inflationary Universe Theory Compliment the Big Bang?

The inflationary universe theory suggests that the early universe experienced a time of rapid and exponential expansion. This period of expansion occurred before the expansion that would be called the “Big Bang.” Develop by Andy Albrecht, Alan Guth, Andrei, Linde, and Paul Steinhardt, this theory suggests that a strong increase in the linear size of the universe in a fraction of a second.

It helps to solve the problems from the standard Big Bang theory very effectively as well.

  • Flatness. Imagine that you’re living on top of a basketball. To you, the universe is obviously curved and has some cool orange bumps on it. You’re in a closed universe. Now let’s say that basketball is expanded to the size of our planet. Suddenly the basketball looks flat instead of curved because if its new size. Goodbye orange bumps too.
  • Horizon. Because of the inclusion of a brief period of extremely rapid expansion, the regions of the universe that seem related, but impossible to be together because of their distance apart, would have touched each other briefly during the initial expansion phase of the universe.
  • Monopoles. The density of magnetic monopoles would drop exponentially during inflation, which would mean their existence would be virtually undetectable since their formation would be produced prior to the period of inflation instead of afterward.

The inflationary universe theory explains the deficiencies of the standard Big Bang theory so well that it is treated as an extension of the original theory. It also helps to explain the original structure of the universe. At its earlies moments, the universe we could observe would be microscopic. Over time, the inflationary process would make it macroscopic. Higher density regions would then be able to condense into galaxy clusters, stars, and other forms of detectable energy.

How Could Inflation Occur in the Earliest Days of the Universe?

The basic idea behind the inflationary universe theory is that expansion occurred because gravity once present in a repulsive form. This allowed the universe to expand because gravity was pushing it outward. The repulsive gravity could then be present because of the gravitational fields, energy densities, and pressures that were present in the earliest moments of universal creation.

We’ve also discovered that in modern particle theories, a material with a negative pressure is easy to construct from a field that may exist.

By putting the two ideas together, the theory of general relativity supports the idea that repulsion, powered by gravity, allows for the rapid expansion of the initial universe. Then, by adding the traditional Big Bang principles, we are able to arrive at the status of the universe that can be observed today.

Testing the Inflationary Universe Theory

One of the best aspects of the inflationary universe theory is that there are two primary predictions contained within it that can be potentially tested. This includes the mass density of the university itself and the densities of the present non-uniformities.

What makes the expansion possible is the fact that there is so much stability in the universe in its early and present form. This means there must be a large amount of dark matter contained in the universe to support galaxy formation and retention. The amount of dark energy could be up to 10 times the amount of visible matter that is observable in the current universe.

We can see this principle in play by observing galaxies that are in clusters compared to galaxies that are isolated from one another. By asking how much energy is required to hold galaxy clusters together and comparing that to individual galaxy stability, it becomes possible to continue supporting the ideas of the inflationary universe theory that are also supported by the theory of general relativity.

What the Inflationary Universe Theory Means for Universal Death

Because of the plausibility of the inflationary universe theory being correct, then the head death of the universe is a plausible fate for our current definition of reality. Because the universe is continuing to expand and is doing so at an increasing speed, the possibility that there would be no more thermodynamic energy one day becomes a real possibility. Processes that increase entropy would no longer be sustained.

This means no processes, including temperature differences, would be able to be exploited within the framework to perform work. Equilibrium would be achieved

It is a plausible outcome because evidence suggests that the universe is forever expansive and will not collapse upon itself. Dark energy is also considered to be a positive cosmological constant with current research. Both would contribute to an eventual heat death as the universe cools to an equilibrium with a low temperature over a long period of time.

There’s nothing to worry about for the time being regarding the eventual demise of the universe. The half-life of Hawking radiation is thought to be 10 to the 100th power, which is ten duotrigintillion – or a googol if you prefer.

The inflationary universe theory is an elegant explanation to help explain the formation of our current reality. There are many great mysteries still waiting to be discovered as well. That’s what makes scientific studies our real final frontier. It embraces the idea of “I don’t know” and seeks a solution.