Top 10 Real Scientific Mysteries That Still Can’t Be Solved

Dark matter holds galaxies together, yet we've never seen it. Placebos trick the brain into healing the body, even though it's not actually medicine. And gravity itself isn't consistent. Some places on Earth mysteriously pull weaker or stronger than others. These are real scientific mysteries that still can't be solved. It's crazy to think about, but when you look at everything around you, all the people walking around, cars, buildings, forests, the sea, stars, planets, entire galaxies, all of that, it makes up less than 5% of all matter in the universe. The rest is something invisible. About 27% is what scientists call dark matter. It's called dark matter because it doesn't give off light or energy. We only know it's there because gravity pulls on things, bending light and holding galaxies together. Without it, galaxies should just fly apart. Then there's dark energy, which is even stranger. Around 68% of the universe is made of this unknown force that seems to be pushing space itself apart, causing the universe to expand faster and faster. Scientists don't actually know what either of those are, though. Decades of experiments have tried to catch a glimpse of dark matter particles in underground labs. Telescopes have been scanning the sky for clues as to what dark energy could be, but we don't really have much more to go on. Basically, 95% of the universe is a total mystery. If we can't even determine what 95% of the universe is made up of, not too surprising that videos like this exist. I've always been perplexed by this one. See, sometimes just believing you're getting treated can actually make you feel better. Doctors have tested this over and over again. Patients given fake treatments sometimes improve just as much as people getting real medicine. I mean, it's worked to a level beyond just an improvement in mood. Brain scans show real changes happening. Pain centers quiet down. Endorphins get released. Even measurable things like blood pressure or heart rate can improve. The effect is so strong that in drug trials, new medicines have to beat placebos before they're actually approved. Now, nobody fully understands why this happens. I mean, how does your brain's expectation seem to actually flip a switch in the body? Why do some people respond more than others? We don't know, but it does go to show just how powerful the mind-body connection really is and how much we still don't know about it. Obviously, placebos don't always work, though. If you're suddenly smelling burnt toast right now, or your arm is getting numb and you're feeling dizzy, do call 911. This is bizarre. Did you know that gravity isn't actually perfectly even across the Earth? In some places, it's slightly weaker or stronger, and it doesn't always match what scientists expect based on the ground below. One famous example is Hudson Bay in Canada. Their gravity is weaker than in surrounding areas. For a long time, researchers thought it was just because glaciers from the last ice age scraped away mass, but even after adjusting for that, the numbers didn't add up. Part of the missing gravity seems to be caused by currents deep inside Earth's mantle, where hot rock is moving around in ways we can't directly see, but there's still no complete explanation for why gravity shifts the way it does in certain places. Satellites like GRACE, the Gravity Recovery and Climate Experiment, have mapped these variations from space, showing dips and swells in Earth's gravitational pull. We know life on Earth started billions of years ago, but the exact how is still a giant question mark. For those of us who don't believe in creationism, that is. The earliest traces of life go back at least three and a half billion years, but how simple chemistry turned into the first living cells, that's still up for debate. One idea is the primordial soup. This is the hypothesis that billions of years ago, shallow pools full of chemicals got zapped by lightning or heated by the sun and eventually formed the building blocks like amino acids. Another theory puts the origin deep in hydrothermal vents on the ocean floor, where mineral-rich water and extreme heat could have provided the right conditions for life. There's also the possibility that life didn't even start here, meaning not on this planet. Some scientists think the building blocks for life may have arrived here on comets or meteorites, but we still can't say for sure. We can map the human brain down to individual neurons, but the biggest question is still how do we actually have consciousness? How do 86 billion nerve cells firing off electrical signals turn into thoughts, emotion, that inner voice in your head at 3 a.m. that just won't stop dredging up all your most embarrassing moments from when you were just in elementary school? Well, this is called the hard problem of consciousness, and nobody's solved it. Scientists can point to which part of the brain lights up when you're afraid, angry. They can look at what part of the brain lights up when you see the color red, for God's sakes. But that doesn't explain why you experience fear or what red looks like to you. Yes, you specifically. Some researchers think consciousness is just a byproduct of complex computation. So, like, the brain is just crunching numbers so intensely, it's always working, and so self-awareness could just come out of that in the process. Others argue it's something more fundamental, maybe woven into the universe itself. Now, you may be thinking, well, I mean, who cares why? Our brains work, just let it be. But the thing is, aside from just philosophizing, understanding consciousness could change medicine. It would obviously be super helpful when it comes to mental health. But for now, our brains are still mostly a mystery. When you think about what makes you you, you probably don't picture the trillions of bacteria, viruses, and fungi living inside your body, because who really wants to think about that? But they're a huge part of the story. I'm talking about what's called the microbiome. Scientists have discovered it can influence almost everything. Digestion, immunity, weight, mood. I mean, some studies have found that certain gut bacteria can affect anxiety or depression. Others show the microbiome plays a role in diseases like diabetes and cancer. But everyone's microbiome is unique, like a fingerprint. And while we know it's important, the details are still a bit fuzzy. Which microbes matter the most? How do they work together? Can we actually change them on purpose to stay healthier? This is kind of crazy to think about, but in a way, each of us is more like an entire ecosystem rather than a single organism. In 2006, scientists dredging the waters of Iceland pulled up a clam that looked ordinary at first glance. But when they counted its growth rings, they realized it was 507 years old. Older than Shakespeare. Older than the printing press. They nicknamed it Ming, because it was born during China's Ming dynasty. Unfortunately though, the researchers also had to slice its shell open to measure its age, which, you know, killed it in the process. But Ming's discovery opened up a whole new line of research. How can a simple clam live for half a millennium or longer? And who knows how long it would have lived if it hadn't been sliced up? We know animals like tortoises and Greenland sharks lived for centuries too, but Ming still holds the record as one of the oldest living creatures ever found. Most animals wear down with age, but these clams, obviously, seem to keep their cells protected from damage much longer. Some scientists think studying them might help us understand human aging, so this research is more important than it sounds. Right after the Big Bang, the universe should have cooked up specific amounts of hydrogen, helium, and lithium. And for the most part, the math checks out, except when it comes to lithium. According to the theory, there should be about three times more lithium in ancient stars than we actually see. This mismatch is called the cosmological lithium problem. Scientists have tried to solve it by tweaking models of nuclear physics, suggesting lithium got destroyed inside stars, or that maybe the early universe didn't behave exactly as we thought. But none of this lines up perfectly with observations. And this is a big deal. If we can't explain lithium, it means our whole picture of how the universe began might need some adjustments. Next up, we have the Fermi Paradox. See, the math says the universe should be crawling with life. There are billions of stars just in our galaxy alone, and a huge number of them should have planets in the habitable zone, where liquid water could exist. And that means, in terms of probability, there should be aliens out there. But so far, we've found nothing. That's what's called the Fermi Paradox, the question of where is everybody? Some scientists say maybe there have been alien civilizations, but they just aren't around anymore, could have wiped themselves out before they spread out through the galaxy. Others think advanced life could be avoiding us on purpose, or they're just so different, we wouldn't even recognize them at all. And of course, there are plenty of people who think we have encountered aliens, and it's just been covered up. But there's also the possibility that we really are alone. Just kind of eerie to think about, that it's just us floating around out here on this ball in the middle of an endless void. I don't really like that thought. Scientists are constantly listening to space for signals, though, trying to find any signs of life. So far, there's been nothing concrete, but there is one rather famous anomaly. Back in August of 1977, a radio telescope in Ohio picked up something strange. It was a powerful 72-second radio signal coming from deep space. So unusual that the astronomer who spotted it circled it on the margin. The signal came from the direction of Sagittarius, and it matched the kind of narrow frequency scientists thought an alien transmission might use. But when they pointed the telescope back in the same spot, it never showed up again. For decades, people have tried to explain this away. Maybe it was a comet passing by, or some kind of military signal bouncing around Earth, but none of these theories fully check out. To this day, no one's ever heard the wow signal repeat, and it's still one of the best possible hints of extraterrestrial communication we've ever recorded. With all that said, though, I've been your host James, and I'll catch you, yes you specifically, in the next video.