5 Great Discoveries That Haven’t Yet Been Made
There are some great discoveries that were made remarkably recently.
One example is the theory of plate tectonics. Everyone is taught in primary school now that the Earth’s crust is broken into several large plates, which move around very slowly, thereby leading to continental drift, and volcanic eruptions and earthquakes where plates meet. But the idea of continental drift, much less plate tectonics, was hugely controversial, and the theory only became widely accepted in the 1960s, by which time a weight of evidence from the ocean floor and from continental margins had been discovered to support it.
At the same time, there remain some huge discoveries that haven’t yet been made; where the extent of our ignorance as a species may well surprise you. You’ve probably heard the quote (probably apocryphal) from the Commissioner of the US patent office in 1899, that “everything that can be invented, has been invented.” We might just as easily fall into the trap of thinking that very nearly everything that can be discovered, has been discovered. It’s arguably this sort of overconfidence in human progress that leads to conspiracy theories such as the idea that cancer has been cured, but that scientists have for a variety of bizarre and implausible reasons, chosen to keep it a secret.
In reality the world of things we don’t know extends further than many people realise. In this article, we look at the discoveries that haven’t yet been made, and that may form the Nobel prizes and shock revelations of the future.
1. Whether alien life exists
The science fiction writer Arthur C Clarke once said, “Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying.”
Have you ever heard of the Fermi Paradox? It’s essentially the idea that since the universe is so vast and there are such a varied assortments of planets in it, it seems remarkable that we haven’t yet heard from any other intelligent life form. Until a few decades ago, this didn’t seem like a paradox, but in the 20th and 21st centuries, the Earth has become increasingly noisy, sending out radio waves, satellite signals and robotic probes. It seems likely that any advanced alien civilisation would be similarly noisy, and yet we have not come across a single trace of them.
Explanations for why that might be the case vary. It could be that species taking their first steps towards space exploration are shielded from interference to develop at their own rate. It could be that other life forms, though intelligent, are so very different from us that we can’t interpret their signals. It could be that we are the very first life form to develop intelligence. More creepily, it could be that we’re among the last, and all that’s out there is millennia-old ruins. You can see why Clarke saw all the options as terrifying.
If we find primitive alien life, such as bacteria, somewhere like the Moon or Mars, it’ll be very hard to prove that it originated there, rather than being the result of contamination from our own explorations. But any step towards further clarity about alien life of any kind would be a huge development.
2. What came before the Big Bang
Staying in space for a moment, another theory that has only been widely accepted recently is that of the Big Bang. The idea of the universe expanding from a single point was first proposed in 1931, and faced widespread opposition. The idea that the universe, and therefore time itself, began at a single point, was resisted in part because it seemed like trying to impose religious ideas on to the study of Physics. But scientists proposing the Big Bang theory made a series of predictions for the evidence that could be found if their theory was correct, and over the course of the 20th century and up to the present day, a growing weight of that evidence has been found.
It’s now the case that physicists are trying to delve back ever further into the infinitesimally small fragments of time immediately after the Big Bang. While there is plenty to be discovered there, it involves the headache-inducing complexities of quantum mechanics.
If anything, though, thinking about what came before the Big Bang is even stranger. To start with, the concept of ‘before’ doesn’t really make any sense here. Time began at the Big Bang, so there was no such thing as ‘before’ it. It may now become clearer why early opponents of the Big Bang theory accused its proponents of bringing religion into Physics.
At the moment of the Big Bang, the universe began to expand, and is still expanding, but what we don’t know is what was in the space it is expanding into before the universe expanded into it. That way of framing things may also be utterly wrong, given that the question in its simplest terms is “what stuff was there before there was any stuff there?” – it’s essentially contradictory. One suggestion is that there was another universe here before ours, but as things stand, we simply don’t know.
3. How general anaesthetic works
Moving away from the huge questions covering the nature of the universe itself, have you ever watched a thriller with someone who’s studied medicine? You might have seen the motif of the hero or heroine who doesn’t shoot to kill like the bad guys do; they just knock their enemies unconscious, where they will awake unharmed some time later in order to be defeated again in the final act. And the medicine student, if they’re inclined to nitpick, might have pointed out that the human body doesn’t work like that. Knocking someone unconscious is both difficult and dangerous. Previous anaesthetics such as chloroform killed somewhere around one in every five thousand people they were used on, and may have shortened the lives of many more.
Thankfully, we don’t have to worry about dying from the use of chloroform when we have surgery now. We do have a method for knocking people unconscious more-or-less safely: we have general anaesthetic, which is only marginally more dangerous than childbirth in a developed country, and – for example – an order of magnitude less dangerous than a hysterectomy. The only snag? We still don’t know how it works. We know that it interrupts the passage of signals along nerves, but not how each type of anaesthetic achieves that interruption. As different anaesthetics are very different in their chemical structure, it seems unlikely that they could all operate in the same way, despite the fact that they have the same effect.
There are many difficulties in studying anything to do with the brain: its complexity, for one. But one significant reason the brain is hard to study is that it is hard to get to. A human brain in functional, living condition can only be found in a human head, and that is somewhat restrictive for research. But new imaging techniques are making it easier for scientists to investigate the brain, so it may be that the particular mystery of general anaesthetic will be solved sooner rather than later.
4. What lies at the bottom of the oceans
We know astonishingly little about the ocean floor. We’ve mapped all of it to a resolution of 5km – but, for comparison, we’ve mapped 98% of the surface of Venus to a resolution of around 100m, and Venus has a surface temperature of 462°C, atmospheric pressure 90 times that of Earth, and clouds made of sulphuric acid. More than half of the more hospitable planet of Mars has been mapped at a resolution of 20m. But only 0.05% of the ocean floor has been mapped at a level that would allow us to pick out, for instance, aeroplane wreckage.
Like the human brain, the ocean floor is difficult to get to (albeit for different reasons). The deepest part of the ocean floor is just under 11,000m below sea level. The deepest humans have ever gone is 10,911m, in the 1960 dives of Bathyscaphe Trieste. The observations of fish made by the divers were the first confirmation that life could exist at the incredible pressures of the bottom of the ocean. One challenge posed to further study that alongside the pressure, everything below about 1,000m down into the ocean exists in complete darkness, so any exploration dependent on sight has to bring its own light source.
The variety of life that exists in the ocean is also still a mystery. Think about the giant squid: a live adult giant squid was not filmed in its natural habitat until 2012, despite the fact that they can be up to 13m long and so it seems they should be relatively easy to spot. Giant squid don’t even go to the deepest depths of the ocean (the pressure would kill them); their range is depths of 300 to 1,000m, or within the zone that light can penetrate. What kind of other discoveries might still remain to be made in the parts of the ocean that are even hard to explore is unknown, but what is clear is there is a lot still out there for us to learn.
5. Why we age and whether it’s preventable
Benjamin Franklin wrote in 1789 that “in this world nothing can be said to be certain, except death and taxes”; Kanye West updated this in 2005 to the arguably punchier, “nothing in life is promised except death.” Leaving aside the question of taxes, why is death certain? And why is the process that leads inexorably to death – the process of ageing – also a certainty?
We have a reasonable understanding of the processes that govern how we age and die. Despite what you might think, ‘old age’ in and of itself isn’t a cause of death; we always die of something else. The top causes of death are heart disease, dementia, cancer, stroke, emphysema and pneumonia – all of which either have age as their most significant risk factor, or, in the case of flu, become much more dangerous when contracted by the elderly.
Central to ageing appears to be telomere shortening. Telomeres are protective caps on chromosomes, but they get shorter as we age, which exposes our DNA to other destructive forces such as oxygen exposure and glycation. This damage to our bodies seems to be what exacerbates all of the other damage – the slowed healing processes that make us much more vulnerable to the diseases, conditions and other hard knocks of life. It may be what makes the flu so much harder to shake off when you’re 80 than when you’re 18, and what makes a fall that you would have forgotten in moments at the age of 9 potentially fatal at the age of 90. But telomere shortening and lifespan don’t seem to correspond absolutely, so there is more to learn in this area too.
But why this all happens in the first place is more of a mystery. Some organisms scarcely age at all, such as lobsters, which unlike most creatures continue to repair their telomeres throughout their lives. They continue to grow and be fertile throughout their lives, and their lifespan is limited not by ageing but by growing to a maximum size, after which point the process of moulting their exoskeleton in order to grow further becomes so exhausting that it kills them, or they are unable to moult altogether, so the exoskeleton degrades and kills them. Which species have the potential to be extremely long-lived (barring accidents) and which ones don’t appears to be genetically determined.
This leads us to the question of whether ageing can be prevented, or at least significantly slowed down. Some researchers have suggested that our efforts in research to prevent or cure the diseases of ageing, such as cancer or dementia, should partly be diverted to researching ageing in general; if we could develop treatments so that all 80-year-olds had the biological fitness of 30-year-olds, the death toll exacted by these diseases would be orders of magnitude lower.
In simple organisms such as c. elegans, techniques to prevent ageing and extend lifespans have been very successful, but they’re less successful the larger the organism, and no technique has yet been shown to work reliably on humans. Part of the problem is that humans have a very long lifespan to start with; c. elegans has an average lifespan in the lab of 3 weeks, so researchers can get results very quickly. The danger with trying this in humans is that what slows ageing in someone aged 30 or 40 might not have desirable results 10 or 20 years later. It all remains to be seen.
Image credits: mountain lake; observatory; route 375; milky way; hospital room; ocean; skincare products; hand.