10 Scientific Mysteries We Still Can’t Solve
Did the Universe Start With a Big Bang?
The Big Bang theory has been the theory to account for the beginning of the universe for years. But is it indeed the ultimate answer?
The theory was dubbed “Big Bang” by one of its fiercest opponents, Fred Hoyle. He thought that the universe was static and eternal — a hypothesis that quickly died. In 1929, Edwin Hubble proved that the universe was expanding. More evidence in favour of the Big Bang Theory followed: in 1965, the existence of CMB radiation, a residue of the Big Bang, was confirmed.
But there is a hitch. The measurements Hubble made in 1929 were disproved in 1990. In fact, the universe was expanding at a slower rate than the Big Bang theory predicted. In response, Alan Guth made some adjustments to the Big Bang theory; he claimed that the universe expanded rapidly initially and then slowed down.
But as critics of the Big Bang theory point out, it can’t be proved. Maybe we have to find a new way to account for the beginning of the universe?
Can We Predict Earthquakes?
Our understanding of Earth’s movements started to form relatively late. Only in 1912 did Alfred Wegener come up with the idea that the continents were in constant motion. In the 1960s, the US navy observed that the seabed wasn’t smooth as it had been assumed up to that point — it was composed of mountain ranges.
Scientists concluded that the seabed was also subjected to volcanic and earthquake activity. This discovery brought about plate tectonics theory, which explains large-scale motions of Earth’s lithosphere. Now we know that an earthquake takes place when two plates rub against each other.
We’ve been able to localize places that are most prone to tectonic activity. But we still don’t know when exactly an earthquake will occur. For example, scientists can predict that an earthquake is due in Los Angeles soon. Which can mean anything from tomorrow to 30 years from now.
What Causes Ice Ages?
We still don’t know what causes ice ages. Milutin Milankovitch proposed a solution in the 1920s. He claimed that the Earth received different amounts of solar energy at different times, because of the way our planet moved. This would lead to ice ages appearing at regular intervals. At first it seemed right, as it appeared that an ice age occurred every 100,000 years.
But Milankovitch’s theory can’t account for some serious irregularities in this pattern — for example, a period of 200 million years without an ice age. Recent theories have focused on the greenhouse effect, but this opens up more questions than it answers. What causes fluctuations of carbon dioxide in periods of time without humans? Scientists bicker about it, but the truth is we don’t know yet.
Is There a Missing Link?
A missing link is a hypothetical evolutionary link between apes and humans. In 1912, Charles Dawson found a skull with a human cranium and an apelike jaw on Piltdown Common near Lewes England. For 41 years, the scientific community believed we found the missing link.
However, this extraordinary finding turned out to be a hoax made by the keeper of zoology at the British Museum, called Hinton. Why would he do it? It was his revenge.
Hinton started working at the museum as a volunteer. When he asked for a salary, he was refused by the keeper of paleontology, Arthur Smith Woodward. So Hinton fabricated the skull in order to undermine Woodward’s authority as a scientist. But the plan didn’t work out too well.
In 1956, William Straus and A. J. E suggested that that Neanderthal was our immediate ancestor. However, new techniques of dating fossils indicated that humans and Neanderthals had lived simultaneously and interacted. The vacancy is still open.
Why Did It Take so Long to Develop Abstract Systems of Communication?
The earliest examples of art date from about 35,000 years ago. However, written language developed only 7,000 years ago and another 2,000 years had to elapse for mathematics to emerge.
Why was there such a large gap between the first abstract drawings and the first system of communication? The most likely thesis states that our brain had to change first. But how? The brain is such a complex structure it may take centuries before we gain a decent understanding of its workings.
How Do We Learn Language?
Scientists weren’t concerned about the mechanics of language acquisition until the emergence of psychoanalysis. In the 1920s, Jean Piaget developed the theory of cognitive development, which stated that the process of language acquisition was encoded in genes and occurred in a rigorous order. Piaget conducted his studies mainly by surveying children.
However, other scientists tried to repeat his studies but ended up with different results. In the end, it was argued that the method of interviewing children was liable to over-interpretation.
Many psycholinguists now think that people have a language instinct. Just as spiders instinctively spin webs, children learn the language of their parents. But what is the nature of this instinct? How come children are able to create original sentences?
What Are Black Holes Really Like?
The concept of black holes met with disbelief at first. When he first heard about them, physicist Sir Arthur Eddington exclaimed: “I think there should be a law of nature to prevent a star from behaving in such absurd way!”.
Black holes had been anticipated by Oppenheimer in 1938. But we can sympathize with Sir Arthur Eddington, as the behaviour of black holes is counter-intuitive. Nobody really knows what’s going on inside a black hole. In the 1990s, scientists discovered the existence of super-massive black holes the size of a billion suns. They tend to be situated at the centre of elliptical galaxies. Did they take part in creating those galaxies? We don’t really know.
How Old Is the Universe?
It’s quite a conundrum. The answers vary from 8 to 20 billion years, which is a generous margin of error. The most mindboggling aspect of the problem is that the universe might actually be… younger than its oldest stars. Studies done in 1994 showed that the universe was 8 billion years old, which implied that the oldest star in the Milky Way was older than the universe. Luckily, measurements done in 1999 disproved the previous studies.
It was a fleeting triumph, though. Yet another study with cutting-edge technology showed that the universe was actually 15% smaller, which meant also 15% younger. According to this new study, there are stars older than the universe itself. What are we doing wrong? Or maybe we don’t understand some fundamental physics laws yet?
Do Multiple Universes Exist?
Science fiction writer Jack Williamson was first to propose the concept of multiple universes in 1952. It inspired physicist Hugh Everett who in 1957 wrote a doctoral thesis about multiple universes. According to his model, every event created a number of universes in which every possible outcome of this event took place.
John Wheeler, Everett’s supervisor, proposed a different version. According to him, the universe was periodically expanding and then contracting to the size of an atom. But some scientists noted that the universe probably doesn’t contain enough matter to collapse back on itself.
Stephen Hawking develop a theory that says that there exists an infinite number of universes with every possible future.
The problem is we can’t really check those theories in practice.
How Will the Universe End?
Some theories assume the universe will start contracting at some point until it achieves the size of an atom. Another big bang will take place and the universe will be reborn.
There is another possibility, though. The universe can go on expanding with galaxies drifting further and further apart. Eventually, the existing stars will use up their fuel and there will be nothing left.