The universe is big. So big, in fact, that even if we learn how to travel at the speed of light and solve all other problems with space travel, we’d still only be able to explore a tiny fraction of what we can currently observe. Of course, even that seems like a thing of the distant, unforeseeable future right now, as our best, most-advanced tools of space exploration today barely allow us to scratch the surface of our own Solar System, let alone the entire universe.
What our tools can finally do, though, is consistently discover entirely new things that we don’t yet understand. Mounting research is proving that the universe is far from the cold, empty void that we once thought it to be. From weird, scary planets beyond our reach to baffling things going on inside our own galaxy, it’s full of a mind-boggling variety of mysteries and phenomena we just can’t explain…
10. Time
Albert Einstein made quite a few groundbreaking discoveries throughout his career, though his most important contribution to science was his theory of relativity. Contrary to the absolute positions of space and time in Newtonian physics, in Einstein’s view, neither exists without the other, and both are relative to each other as well as the observer.
While it revolutionized the field of science, it also elevated time from a seemingly uniform dimension of reality to something far more complex. If time is relative and has no meaning outside the fabric of spacetime, then, what exactly is time?
For now, we can’t say for sure. In fact, we don’t even know if time exists as an absolute function of the universe or not, as every one of our mathematical equations and theories work the same without it. Moreover, we don’t know why it only seems to go forward and always works to increase the amount of disorder in the universe, also known as entropy. That’s why you never see broken pieces of glass coming together to form a complete window, or living cells repairing and fixing themselves over time to get younger.
9. The Universal Applicability Of Mathematics
One of the most fascinating things about mathematics is its applicability across different, wildly unrelated fields. Fluid dynamics, for one example, doesn’t just help explain fluids and their complex movement. It’s also applicable in economics, military strategy, industrial logistics, banking, and a variety of other areas that don’t seem to be connected in any way.
Within the purview of natural sciences – like physics, chemistry, biology and other fields that deal with observations from nature – this universal applicability of mathematical principles isn’t just odd, it’s downright baffling. It’s easy to find multiple examples of mathematical concepts – like Pi – that work with seemingly distinct areas of study, from spatial geometry to space exploration to banking. It doesn’t make sense – almost like opening a series of locks with a bunch of keys and getting it right in the first or second go every time.
8. Fermi Bubbles
Fermi Bubbles – named after the gamma-ray telescope that first captured them in 2010 – are two humongous, interconnected bubbles of gas, dust and cosmic radiation seemingly emanating out of the black hole at the center of the Milky Way. Only visible in gamma-ray light, they’re about 50,000 light years in total length. For perspective, the entire Milky Way is about 100,000 light years across, making these bubbles perhaps the single largest structure in the galaxy.
For now, that’s pretty much all we know about them, except that they’re also accompanied by unexplained bursts of energy only visible in radio frequencies, along with mysterious hourglass-shaped X-ray structures surrounding the center. One study from May 2020 suggests that they might be related to bursts of gas and dust from the black hole in some way.
7. How Big Is It?
There’s no widely accepted measure of how big the universe really is, or even if it’s measurable with our tools and parameters. From our point of view, we know that it expands to about 46 billion years in every direction, which forms the boundary of what we know as the ‘observable universe’, though that’s hardly its real boundary. In fact, quite a few scientists think that the universe might not have a clearly defined edge at all.
That number merely means that the first ray of light produced after the Big Bang is now 46 billion light years away from us, as the universe is expanding at an accelerating rate. There’s no reason to believe that the edge of the observable universe is the edge of the actual universe, though if it’s not, what lies beyond the realm of spacetime? As of now, we have no way to even guess that.
Its size isn’t the only problem – we don’t know its shape, either. Is the universe spherical? That’s what most of us assume, though again, we don’t have any evidence to prove or suggest that. For all we know, it might not be a uniform, three-dimensional sphere at all, but rather something like a donut.
6. The Center Of The Milky Way
If we’re ever able to journey to the center of our galaxy, we’d likely find quite a few mysterious objects and phenomena we’ve never seen before. One of them is the supermassive black hole called Sagittarius A, which only shows up in the photos as a faint, barely visible radio source. That’s only a wild guess, too, as there’s a growing school of astronomers that believes that it might be some other type of matter altogether.
What we do know for sure, though, is that it’s unlike anything we’ve seen before. Some astronomers suspect that it’s a Galactic Center Radio Transient – another emerging class of objects observed in other regions of the universe that we don’t really get.
The center of the Milky Way is also home to huge strands of light – some more than 150 light years across, arranged in symmetrical, artistic patterns that we can’t quite explain. First discovered in the early 1980s, some astronomers think that they’re related to the suspected super black hole at the center, or even the above-mentioned Fermi Bubbles, in some way.
5. Supervoid
The ‘supervoid’ refers to a humongous region of nothingness about three billion light years from Earth. It’s not exactly empty, but contains 20% less matter than any other part of the universe we can see, spanning across a total distance of over 1.8 billion light years. It’s a part of what the cool scientists are calling exotic physics – a new type of physics that deals with baffling phenomena beyond the frontiers of our knowledge.
Unlike the more or less uniform distribution of matter in the rest of the universe, the supervoid is unusually under-dense, and we don’t really know why. It’s unusually cold, too, and coincides with another discovery made in 2004 called the ‘Cold Spot’, except the lack of density only accounts for about 10% of the coldness. Moreover, there’s something bizarre at its center that causes any light passing through the void to lose its energy. It’s not a black hole, as black holes emit very clear X-rays and radio waves, though something even emptier and hollower than the rest of the void.
4. Strange Matter
On first look, strange matter might sound like a general grouping of multiple phenomena we don’t understand – like dark matter or dark energy. Strangely enough, if we may, that’s not the case, as it refers to a specific type of matter that seemingly shifts between the states of matter and antimatter like it’s nothing. First theorized by two MIT scientists back in 1978, strange matter has since been one of the most bizarre phenomena we’ve observed out in the wild.
Of course, we haven’t actually observed it in space, as strange matter is only suspected to be found at the center of neutron stars – super-dense celestial objects formed after the death of stars. At those pressures, even the most fundamental building block of the universe – quarks – cease to exist in their natural form. The only thing that can stay stable at those pressures is the strange quark, or s quark, which can group together and form strange matter.
It’s all hypothetical – as we have no neutron stars lying around in a lab to check for ourselves – though some suspected properties of strange matter have been observed in the lab. Some scientists believe it to be contagious and dangerous, as strange matter could turn other normal types of matter strange, slowly creeping across the universe and engulfing everything in its path until everything is strange. Thankfully for us all, the center of a neutron star is nearly impossible to escape. For now.
3. The Darwinian Theory Of Evolution
One of the biggest mysteries of the universe is its seeming emptiness. Why, even after actively looking for so many decades, have we never been able to discover any signs of life other than our own? One could argue that the universe is too big and we’ve only just started exploring it. That might be true, but we’ve still managed to observe quite a large part of it for telltale signs of life. So far, we’ve found none.
According to one fascinating theory, it might just be due to the Darwinian theory of evolution, only applied to universes instead of forms of life. First proposed by the theoretical physicist Lee Smolin, it suggests that universes follow the same principles of evolution and natural selection as life on Earth. As stars turn into black holes, according to the theory at least, they give birth to black holes and multiple other smaller universes with slightly different parameters.
While most of them die without the development of any form of life, ours might have been a more successful specimen, even if it wasn’t too successful. Life does exist here, though only in one random corner of an insignificant galaxy rather than as a general rule of the universe. Who knows, there might even be universes teeming with life in every corner somewhere out there, as well as universes that are even emptier and colder than ours.
2. What Is It Made Of, Really?
Obviously, it’s impossible to know everything the universe is made of. We can’t even observe most things beyond a small circle within our solar system, let alone calculate the chemical composition of colossal objects in the most distant corners of our universe. Still, you’d think that we have some clue.
As it turns out, we really don’t. Visible matter that follows the rules of physics we know constitutes barely 4-5% of the entire universe. Of the rest, 27 percent is taken up by dark matter – a mysterious type of matter we only know about due to its glue-like effect on distant galaxies and other objects. The remaining 68% is dark energy, easily one of the most mysterious forces we know of in the universe. It seemingly permeates everything we can see in outer space, except we don’t know anything about it, other than the fact that it’s the force responsible for the rapid expansion of the universe – sort of like the opposite of gravity. Speaking of gravity…
1. Gravity
Gravity is by far the weakest of all the four main types of force in the universe – the other three being electromagnetism, and the weak and strong nuclear forces. Yet, it’s the most dominant. You’d find superstructures larger than anything our minds can comprehend in the most distant parts of the universe still following its basic rules. In fact, gravity and electromagnetism are the only two forces with infinite reach, though EM doesn’t even come close to the influence gravity has on reality. It works as an accumulative force, rather than the positive-negative canceling out of the other forces.
What we don’t quite understand, however, is how it works at the quantum level, and that’s putting it simply. We have no clue what gives matter its gravitational properties, or exactly how it interacts with spacetime, even if we definitely know that it does. Time dilation caused by gravity, for one example, is actively accounted for in geo-mapping equipment.
Like time, Einstein was instrumental in shaping up our modern understanding of gravity, and many of his predictions – including gravitational waves – have been proven real in the past few years. We now know that gravity sits at the fundamental core of the nature of our reality, though we’re still no closer to explaining it than he was.