Are some things unknowable? An analysis on different things in our universe that we may or may never know about.
There are a lot of different things we can explore in physics, from quarks to the universe as a whole. When we think about all this, there is a possibility that we cannot know everything; that there is something out of our reach. As humans, our capacity to know and think is also limited to some point. There is a certain extent to which we can store information, and understand it, in our small pink, squishy organ that we call the brain. There are a lot of things that have happened billions of years ago, and to our current understanding, it is extremely difficult to travel through time.
How our universe truly began is a hot topic for debate in the physics community. The most accepted theory is the big bang theory, but is that the answer? A lot of evidence indicates that this may be a possible way it started but we can never truly know unless we witness it. Maybe it is also possible that the universe has always existed, thus disproving all known theories. All of these are real possibilities and things we cannot definitively answer. Maybe in the future, with new technology and scientific methods, we can obtain new evidence that may finally answer this question. The question of whether something is 100% unknowable depends on many factors.
Another popular theory and one that is widely used in sci-fi is the multiverse theory. This states that there are an infinite number of other universes like ours, similar and different in every way. Can we ever know if this is the case? We currently estimate the observable universe to be 93 billion light-years in diameter, and that is only the observable part. Taking into account the fact that no matter can have a speed greater than light, this would suggest that exiting our current universe is impossible. We can conclude this using the fact that dark energy and dark matter are contributing to the expansion of the universe at future rates faster than the speed of light. This means in an infinite amount of time; we would never leave our own. Unless future civilizations are cleverly able to connect different parts of space-time to travel huge distances in seconds, this seems impossible.
We can also comment on the dual nature of light. Is it a wave, or a particle? Or both? Or neither? How can we tell? Light always seems to contradict its properties, sometimes acting as a wave and sometimes as a particle. We can establish these differences, but can we truly know its real, definite nature? Every experiment conducted has been unable to do so.
Coming back to the topic of the beginning of the universe, what was there before the universe? Was it another universe? Or plain nothingness? This is a period where time didn’t even exist. This is something that has the potential to be truly unknowable, even with immense technological development. Using high power telescope, we can view billions of years into the past, and we can collect limited evidence about those times. But we can’t see something (or nothing) that existed before everything came into being.
It is said that the big bang if it happened, should have created an equal amount of matter and antimatter as well. If this were the case, nothing would exist today due to the annihilation of different pairs of each. But curiously, today, everything we see around us is all matter. Did matter defeat antimatter? Or were they not created equal in the first place? Questions like these can make someone ponder over the past. On the topic of matter, what are dark matter and dark energy? We cannot interact with them at all. A majority of the physics and astronomy community accepts that they exist. It may not be at all possible for beings like us, made out of matter, can find and detect something completely different.
The last, interesting example is that of dimensions. We all know our (x,y,z) coordinate system representing our known 3 dimensions: height, width, depth. But what is there is a 4th dimension? Maybe a 5th? Is it possible that we can know? Edwin A. Abbott’s book “Flatland”, describes the journey of a square in the 2D world. In the book, Abbott refers to the 3D world as “Spaceland”, a place where space and volume exist. When a sphere from said world travels through flatland, the square sees the sphere first expand and grow than diminish. This is the first interaction we see between 2 different dimensions and something like what we would see if a 4D object traveled in our 3D world. A 4D object is something we can never comprehend using our 3D brains. It can be compared to a stick figure. It can only travel right, left, up, and down. The concept of it moving back and forth, in and out of something is foreign and incomprehensible to it. This is similar to us. A 4D cube is called a tesseract, and scientists have tried to make it as realistic as possible using animation, but it still boggles one’s mind. Like each face of a cube is a square, each face of a tesseract is a cube. In simple terms, it is the result of when 2 cubes’ vertices are joined together, like when 2 squares’ vertices being joined forms a cube. Mind-boggling right? Most agree that the 4th dimension is time, and the plane in which spacetime exists. A 4D being would be able to travel back and forth in time. All this theory is fascinating, but is this “knowledge” truly obtainable? Even with the best of technology we wouldn’t, and this is the one example where something is nigh impossible to understand and to know about.
To conclude, in the current time of the 21st century, a lot of things are unknown, but that doesn’t mean they are definitively unknowable. With the right thinking and technology, it is impossible. Only very few concepts such as dimensions and pre-universe era are things that even with unlimited resources and technology, we wouldn’t be able to understand. Depending on the time period, the factor of unknowability highly depends on technological development during the same time period.
https://physics.mit.edu/news/pondering-the-unknowable/
https://www.press.umich.edu/pdf/0472097970-fm.pdf
https://www.livescience.com/34052-unsolved-mysteries-physics.html
https://www.space.com/theory-of-everything-definition.html
https://www.space.com/20930-dark-matter.html
