The scientific community has come a long way in understanding our Universe and how it works. Yet, there is still a lot we do not know. As Werner Heisenberg once so eloquently put it, "Not only is the universe stranger than we think, it is stranger than we can think." How do we make sense of our Universe and the nature of reality? Physics. You have probably taken a physics course or two. One way to think of physics is as the science of the Universe and everything in it. In fact, the word physics derives its name from the Greek word φύσις (phýsis), which translates as "nature".
Along with chemistry and biology, physics is a hard science that uses testable predictions, hypotheses, experiments, mathematics, and modeling. Anyone studying or working in any subcategory of the subject is sure to tell you that the world of physics is exciting. It helps give us a peek behind the curtain of reality.
In many areas related to physics, such as particle physics, astrophysics, and quantum information science, the more we learn about the Universe, the stranger it seems to become. Perhaps that is why the science fiction genre has such a special place in modern culture, and among physicists. Today, we are going to look at some of the strangest mind-bending ideas that the world of physics propose, both running theories and thought experiments.
1. There might be evidence of a parallel universe going backward in time.
Earlier this year, the internet went crazy with news of NASA's alleged discovery of a parallel Universe where time flows backward. Of course, if you have learned anything over the recent years, it is that you should take everything you see and hear on the internet with a grain of salt. So, the next obvious question; Is it true? The short answer is no. The story was way overblown. In short, NASA scientists did actually find evidence of fundamental particles that may completely alter our current understanding of physics. Or, they could simply be particles interacting with ice in an unknown way.
Playing with the idea of the former assumption, the particle signals were discovered during an experiment in Antarctica. While researchers claim there is zero evidence of the existence of a parallel universe where time moves backwards, it is fascinating to consider. The fact that it is not true does not make the idea any less interesting. If such a parallel universe did exist, it would be the complete opposite to ours, in which time moves backward, where positive is negative, where left is right, etc.
2. Parallel Universes could really exist.
Building off of our previous entry, we should note that scientists have not completely pushed one of the favorite tropes of science fiction aside. And there is some evidence in physics pointing to the possibility of parallel universes. Essentially, a parallel universe is exactly what it sounds like, a universe that exists alongside ours, but which is not detectable. In this Universe, everything, or only a few things may be different. You might be a footballer, a pro gamer, a famous writer, or designer.
We do not know for certain whether the universe is flat, spherical, or hyperbolic (to name the three most likely shapes). If the Universe is flat, this could imply that there could potentially be many universes out there, possibly infinite. However, the fun doesn't stop there. Tufts University cosmologist Alexander Vilenkin thinks that our Universe is just a "bubble," part of an infinite network of other bubble universes. What is even crazier is to consider that the laws of physics could work differently in these alternate universes.
3. Wave-particle duality is not intuitive...at all.
This one has us scratching our heads. According to the principle of wave particle duality found in quantum physics, matter and light exhibit the behaviors of both waves and particles, depending on circumstance. Waves can exhibit particle-like properties, and particles can exhibit wave-like properties. In quantum physics, this allows us to make descriptions of matter and energy based on wave equations that center around the probability of a particle. This is one of the many reasons why particle accelerator research is so exciting.
4. Quantum entanglement is spooky.
Albert Einstein called quantum entanglement, "a spooky action at a distance," and you are about to find out why. In short, entanglement describes when particles are connected so that actions performed on one affect the other even if they are separated by great distances. Say, if you had two entangled electrons. Let's call them particles "A" and "B." Now say we did something that changed the state of particle A; this would cause particle B to take on the state of particle A, regardless of the distance between them. But, wait, there's more. This change in state is theorized to happen at least 10,000 times the speed of light; almost instantaneously. Researchers are not exactly sure why this happens or how it is possible, but it does appear to exist. Researchers from the University of Glasgow snapped a picture of this phenomenon, just last year. See, it is spooky.
5. You might be Neo from the Matrix.
Simulation theory is another fun physics concept, especially this year. With all the weird things happening in the world, it may actually be comforting to think that we are living in a simulation. Initially proposed by Nick Bostrom, Simulation theory centers around a modern hypothesis that has roots in the 17th century, when philosopher René Descartes suggested something similar.
Simulation theory supposes that we're living in an advanced digital construct, like a computer simulation, that some higher form of intelligence oversees. Think Sims or the Matrix. Nick Bostrom breaks down this "thought experiment further in his published paper, "Are You Living in a Computer Simulation?"
Bostrom suggested that our world might have been created by members of an advanced “posthuman” civilization with vast computing power who have chosen to run simulations of their ancestors.
Bostrum's argument is extrapolated from observing current trends in technology, including the rise of virtual reality and efforts to map the human brain. After all, if there is nothing supernatural about what causes consciousness, someday we should be able to reproduce it. When that happens, it will just be a small step to a post-human world.
Now, you might want to be sitting down for this next part. While doing some research on Super String Theory, theoretical physicist Jim Gates came across a shocking potential discovery. He claims to have discovered what could be described as computer code in the math that underlies our world, similar to the checksums that make the Internet work. This is all still very theoretical, but no less shocking in its potential. In fact, the idea of simulation theory has so gripped the tech world that there are already two tech billionaires secretly engaging scientists to work on breaking us out of the simulation.
For more on simulation theory, be sure to stop by here.
6. Quantum temperature. What?
Quantum temperature does sound like a plot device in a science fiction movie. But, be patient. Imagine one day, you and your friends decided to bake cookies. You acquire and mix all the ingredients together, finally placing your cookies in the oven, setting the correct temperature for baking. However, upon checking on your cookies later on, nothing has changed, and your oven is still at room temperature. Or maybe some of your cookies started baking, and others have not. What has happened? You either need a new oven or, you are hanging out in the quantum world.
In the quantum world, if you have not learned already, things act strangely. Normally, heat flows smoothly from hot spots to the adjacent cold ones, warming up an object or room evenly. Not in the quantum world. Researchers have discovered that here temperature behaves in odd ways. Using graphene, a material made of a single-layer sheet of carbon atoms, researchers found that electrons carrying heat can move in waves, causing some spots of the graphene to be warm and other areas to remain cold. They can even control these waves. Harnessing this effect would be revolutionary.
7. The quantum zen effect will melt your brain.
You are probably familiar with Schrödinger's cat. It is basically a meme at this point. In short, it is a thought experiment where a cat is trapped in a box with a radioactive source that has an equal probability of decaying or not decaying over the course of an hour. If the radioactive material decays, this triggers a detector that releases a poison that kills the cat. The question is, how can we know if the cat is dead or alive after one hour? Or, according to Schrödinger, "when does a quantum system stop existing as a superposition of states and become one or the other?"
In other words, until we actually open the box, the cat exists in two states simultaneously. The moment we take a look, the state is revealed. Nothing new.
However, if you were able to peek into the box thousands of times per second to keep an eye on the radioactive material, this could actually alter its behavior. In theory, you would be able to delay or accelerate the decay of the radioactive material. This is is known as the quantum anti-Zeno effect. Spend some time thinking about that.
Perhaps we are not supposed to understand our Universe fully. Or, maybe there is someone out there who already has? As Douglas Adam once wrote, "There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened."
What is your favorite theory in physics? What ideas still blow your mind? For more topics on physics or the quantum world, be sure to stop by here.