Throughout all of history, humankind has wondered about the construct of the universe. Many questions have been pondered, like how was it formed, and by whom, and why?
There is no shortage of wondering about its mysteries.
Throughout the generations, scientists have explored many ideas to explain our cosmos and its future. And many of them are pretty far-fetched, to say the least.
Let us examine six of the strangest beliefs and ideas about the universe.
Plasma-filled cosmos
Many scientists prefer the Big Bang theory, which is backed up by two key observations. Cosmic microwave background (CMB) and the expansion of the universe. It was much smaller and hotter immediately after the Big Bang, filled with a luminous plasma like the sun. As a body mass of radiation filling the whole of space, we can still see the end of this super-hot phase.
Radiation in the universe has been cooled down to minus 454 degrees Fahrenheit (minus 270 degrees Celsius) over billions of years, but radio telescopes can still detect it.
Assuming our universe has always expanded at its current rate, the CMB looks virtually the same in every direction. Yet many scientists believe it experienced a brief period of rapid expansion after the Big Bang, suddenly expanding from a small scale to several light-years in just a fraction of a second.
The multiverse
According to the conventional view of the Big Bang, in order to explain the uniformity of the CMB, there must have been an early spurt of superfast expansion. Many scientists believe that our universe became another tiny bubble in the vast sea of inflating space as it dropped out of the inflationary phase.
According to Paul Steinhardt’s “eternal inflation” theory, other bubble universes keep popping up in other parts of the inflationary sea, making the entire ensemble a “multiverse.”
Even stranger, other universes could possess different laws of physics, like a different speed of light or stronger gravity. Even though we can’t see the other galaxies directly, one of them could collide with ours. According to some scientists, such collisions can be traced back to the CMB’s “cold spot.”
Superfluid space-time
We can think of the universe as existing in four-dimensional space-time, even if space only has three dimensions. According to some theories, the universe is not just an abstraction of physical objects, such as stars and galaxies. Still, it is a material substance, similar to an ocean of water, as proposed by Stefano Liberati and Luca Maccione in Physics Review Letters.
Similarly, space-time is composed of microscopic particles on a deeper level of reality than our instruments can reach, just as water is composed of countless molecules.
According to the theory, space-time is a superfluid with zero viscosity. A peculiar property of these fluids is that they cannot be made to rotate in an orderly way, as a liquid can when stirred. Upon breaking up, they create tiny vortices, which may be the seeds from which galaxies develop in the case of superfluid space-time.
Mistaken gravity
Gravity remains the sole force in physics that impacts matter on a vast scale, so theories of the universe depend on it. However, gravity alone cannot explain specific astronomical observations.
Despite the gravitational pull of their visible galaxy, stars moving toward the outskirts of a galaxy are moving too quickly to remain in orbit. Similar to clusters of galaxies, it seems that something more substantial than gravity holds them together.
Two solutions are possible. Typical scientists hold the view that the universe has unseen dark matter that provides the missing gravity. Scientists proposed Modified Newtonian Dynamics (MOND) in 2002 in the journal Annual Review of Astronomy and Astrophysics as an alternative to our current theory of gravity. Despite being equally consistent with observations, MOND and dark matter have not yet been proven. We need to conduct more experiments.
Braneworld
We take it for granted that the universe is three-dimensional – you can move in three perpendicular directions. There are, however, some theories that suggest another dimension – which we cannot see directly – in another perpendicular direction. We refer to this higher dimensional space as “the bulk” and our universe as a three-dimensional membrane – a “brane” – that floats within it.
Despite its complexity, the braneworld picture solves several physics problems. Researchers from both Harvard University and the University of Maryland have proposed the existence of parallel branes that could explain the asymmetry in subatomic forces by suggesting the presence of other branes.
A theory must also make new predictions that can be tested experimentally, not just explain facts we already know. For the Randall-Sundrum model, such tests might involve measuring gravitational waves emitted by black holes linking one brane to another.
Simulation theory
Until now, all the theories have come from scientists – but here’s one from philosophers. Who says that all of the information we get from the universe comes from our senses and scientific instruments?
Perhaps the entire universe is nothing more than a sophisticated computer simulation. The “Matrix” movies popularized the idea, but some philosophers take it seriously, even though it sounds outlandish. However, a valid scientific theory cannot be proven either true or false because there is no way to prove it.
