Physics students and enthusiasts would have probably heard this phrase before at least once in their lives: “There is nothing new to be discovered in physics now. All that remains is more and more precise measurement”. Stated by physicist William Thomson, Lord Kelvin in 1897, he concluded that statement after looking at all the immense advancements in biology, astronomy, and electricity. However, that same year, the electron was discovered by physicist Ernest Rutherford. Ultimately, it made physicists realise that their understanding of physics and knowledge of the universe was nowhere near completion. Instead, it seems like every discovery leads us to even bigger and deeper physics questions.
If anything, this teaches us that the mysteries of the universe are as big and wide as their existence, leading humankind to consistently search for answers. While it is true that we are still far from having those answers about life, the universe, and everything in between answered – it only means that we have plenty of questions, and possibly even more each day, to ask! Solving these physics mysteries may potentially help individuals understand not only the creation of the universe but also how it works and possibly ends.
With the never-ending questions in the world of physics, we share 5 of the most engrossing ones to learn:
1. Dark energy: what is it?
The universe just does not add up, no matter how hard astrophysicists try; while gravity is tugging space-time inward, it is expanding outwardly at an increasing rate. To explain this fascinating natural phenomenon, astrophysicists have postulated an unseen force that offsets gravity by pushing space-time apart – known as dark energy. According to the most commonly recognised explanation of dark energy, this is a ‘cosmological constant’, a fundamental characteristic of space that exerts negative pressure on space, causing it to separate.
More space is generated when space expands, and in doing so, greater dark energy increases as well. While the studied expansion rate shows that scientists are aware that the sum of all dark energy exceeds 70 per cent of the entire universe, no one, however, knows where to seek it. In the past few years, the only thing that the finest researchers could do is narrow down the place in which dark energy might be tucked away – the subject of a study published in August 2015.
2. Do parallel universes exist?
Astrophysical evidence shows that space-time is not curved but rather ‘flat’ and continues indefinitely. If that is the case, the universe is merely one speck of an endlessly gigantic ‘quilted multiverse’. This essentially means that the endless array of prospective particle arrangements within each cosmic speck dictates the existence of parallel universes. If anything, this has only raised further questions: Is this logic reasonable, or is it simply a flaw? If so, how can one ever know if parallel universes exist?
3. Is string theory true?
String theory enables scientists to integrate the 4 forces of nature into a unified structure by reconciling the principles surrounding particles (known as quantum mechanics) with the rules concerning space-time (known as general relativity). While it may sound fairly understandable, string theory only functions in a universe comprising 10 or 11 dimensions: 3 enormous space dimensions, 6 or 7 compressed spatial dimensions, as well as a time one. Since the compressed spatial dimensions are so tiny, there is, unfortunately, no means to detect something that small. Hence, there is really no method to test whether string theory is correct or not.
4. What is in a black hole?
A burning question lies regarding a black hole that most, if not all, are eager to find out: when an item is dragged into a black hole, what simply happens to it? Existing beliefs and theories suggest that it is pretty much impossible to obtain any information, should you drop an object into a black hole. This is because a black hole’s gravity is so powerful with an escape velocity faster than light, although light is the fastest known element on the planet.
In 2015, Stephen Perry and Stephen Hawking proposed that information is kept on a black hole’s boundary, known as the event horizon. But even so, physicists cannot seem to agree but rather disagree on said explanation.
5. Do sound waves make light?
A significant number of unresolved problems are related to particle physics; however, certain mysteries may be noticed in a bench-top lab setting, such as sonoluminescence. Bubbles will develop in water when sound waves are applied; the outside pressure presses in on the lower-pressure air, causing the bubbles to collapse swiftly. When the bubbles burst, they release light in trillionths-of-a-second flashes.
The issue with this is that it is unclear where the light comes from. Electrical discharges and small nuclear fusion reactions have all been proposed as possible explanations. However, there is no clear explanation as to how sound waves cause these lights to appear in a bubble.
Understanding the universe around us may seem like an uphill challenge, but it would be wise to remember that all answers we have now about the various aspects of life started from asking questions. The journey to uncover all these secrets is guaranteed to be filled with challenges and unimaginable problems that require the right mindset and skills to overcome.
If you are keen to learn more about other unsolvable mysteries or simply looking to improve your physics grade, look no further and enrol yourself at Best Physics Tuition™ Centre in one of our H2 physics tuition classes! Our amiable and professional physics tutor is more than ready to help you achieve that ‘A’ grade you desire. And who knows, you might just be one of the scientists in the future who can finally put an end to any of these physics wonders.