The Hawking Horizon


Black holes are a phenomenon that the greatest scientists of our time have tried to understand, but is proving to be quite the challenge.

However, after many years of thought put into it, there were some theories that were thought to be true. But then came none other than Stephen Hawking, and turned the world upside down.

Up until now, it was believed by most that black holes have something called the event horizon, an imaginary line where nothing that crosses it can go back, even light. Hawking, in his most recent paper “Information Preservation and Weather Forecasting for Black Holes”, says that there is no such thing as an event horizon, but rather an apparent horizon. Basically, it’s the same thing, but less strict in shape (due to continuous quantum fluctuations) and which can occasionally let matter and energy out but changing them enough so they can’t be recognized.

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Stephen Hawking, has a new theory which doesn’t disappoint

The black hole puzzle has been treated using our two basic physical theories: quantum mechanics and general relativity. However, these two laws don’t get along that well, so when you mix them, anything can happen.

In this case, the weird happened when a black hole evaporates. Quantum mechanics says that matter (or information) cannot be lost, so it would leave the black hole through radiation. But in doing so, it would release outstandingly high amounts of energy, creating, literally, a firewall. But general relativity says that you can’t cross an event horizon, and this disagreement between the theories creates a paradox. Or as it is commonly known, the firewall paradox.

Let’s put it this way. If an astronaut was falling down into a black hole, quantum mechanics says that it would die of radiation and burning thanks to the firewall. General relativity says that it will be trapped in the black hole, since it can cross back the event horizon, and will die of the extreme gravitational conditions inside this phenomenon. In either case, our space explorer doesn’t survive, but in different ways.

The famous scientist has proposed the existence of this apparent horizon to solve this problem. If it was true, it would cancel the paradox, but it would create something else.

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A Balck Hole, one of the biggest enigmas for scientists, even the greatest.

With this new horizon, matter or energy could escape, but it would also scramble them up, because of a black hole’s gravity, so even though they could potentially get out, they will have been so messed up that they could not be reconstructed. It would not be destroyed, so it agrees with quantum mechanics, but it’s original structure will be lost.

This polemic statement has already provoked a response from many scientists, since it would completely change our current definition of a black hole, a region in space from which nothing can escape; or so it was thought.

 

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Edge.org


edge org

Logo from Edge.org

Edge.org is a website founded with the sole purpose of joining the greatest minds of this world together to make the extraordinary happen. To do this, a question is asked every year, about the world as we know it and how it can change, and everyone is free to answer it. Over 15 years of opinions, thoughts and ideas are stored in this site, the online version of the ‘Reality Club’, the famous group of intellectuals that came together to discuss the questions they couldn’t answer. Currently, and due to its popularity, many well-known scientists answer it every year to motivate everyone to think about the world around them.

This year’s question is:

 What scientific idea is ready for retirement?

 Many famous scientists have contributed to this project with their ideas, some examples being:

Richard Dawkins, biologist, professor at Oxford and author; who believes that essentialism is obsolete. This is a term used to describe the way humans think of everything belonging to a separate fraction, with nothing being able to exist in between. Like what happens when people argue about abortions, saying that at one point it isn’t human yet, but at another it is. It is supposed to be gradual, where it is a quarter human, then 3 quarters… where the distinguishable point in which an embryo becomes human can’t be discerned completely

Irene Pepperberg, author, researcher and lecturer at Harvard University; believes human superiority is not true. Although it is true that humans are special, other animals are too. Humans can’t detect very slight changes of temperature like some snakes, we can’t see ultraviolet light like bees, and we can’t migrate for hundreds of kilometers by using an ‘internal GPS’.

Azra Raza, professor in Medicine in Columbia University, New York; says that cancer research in mice is not useful. Cancer develops differently in mice than in humans, and adding human cancer cells to rats would involve injecting drugs to suppress an immunological response, which would affect the results. Altogether, results from such experiments don’t provide an accurate depiction of a drug’s usefulness.

To answer the question, in my opinion, the term reality is no longer practical. The definition of reality is “the state of things as they actually exist, as opposed to an idealistic or notional idea of them”.

However, nowadays, with all these theories about alternate universes, or quantum physics, I feel like we no longer know what is real, what really happens, but rather what we think happens or what data use for our calculations.

The theory of multiverses and infinity, where every possible outcome to a situation happens but in another universe, is mindboggling, because even though to us there is only one reality, if this theory is correct, there is another one of us whose reality is different. So who is right? Are we both right? But how do we know the answer?

Another example of this situation is virtual reality, having a world online. You can play a game on the internet, build a house in it, etc. but once you go offline, is that house really there? It’s not physical, at least in the traditional way, but more like an idea stored in chips and computers.

And every time a new theory is thought of, when calculations go wrong or results given don’t agree with predictions, theoretical values can used, so we are not actually describing reality, but our reality where we idealize every quantity to get an understandable result.

With these manipulations of reality, we can’t really know what actually happens and what we hope/believe happens, so reality is no longer real.

If you want to share your opinion, go to www.edge.org and answer it yourself!

Caffeine Will Get You A’s


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Caffeine, the molecule for students

There are few students that have coffee to thank for getting them through university, though the reason for this may not be the one you think.

The key of its success is a substance called caffeine (C8H10N4O2), which not only helps fight sleep, therefore allowing students to stay up all night studying, but a new study suggests it might also help strengthen long term memory.

Before this study, it was a known fact that memories were more intense thanks to caffeine, but the explanation for this was that it increased attentiveness and alertness. However, researcher Michael Yassa from the University of California put together 2 groups of individuals, and gave a pill containing 200 milligrams of caffeine to one group, and a placebo to the other. Then, they were made to analyse some images, and a day later, returned, and took a test. The test displayed 3 types of images: some from the ones they’d been shown, some similar to these, and some completely new.

The results were clear. The difference between the groups in distinguishing the old images and the new ones was insignificant, but there was a considerable difference in the identification of the old ones and the similar ones.

This proved that caffeine helps in the process of memory consolidation, meaning it helps make memories stay longer in our mind. So studying with a cup of coffee will help make you remember the information better, though the amount of caffeine is very important. Too little caffeine won’t do the job, and too much could have side effects such as headaches. The perfect amount is about 200 milligrams, which is the equivalent of two espressos.

But, unfortunately, this doesn’t mean that having a cup of coffee just before an exam will bring back the memories of the answers. Caffeine helps make longer lasting memories, not recall them better.

2013 Review Part 2


In the previous article we saw how scientists from all around the world had managed to print a gun, create a fake burger and allow a human and a rat to communicate only using their minds! We also saw how two excelling scientists were honoured with the most prestigious scientific award, the Nobel Prize, for their theory of how particles gain their mass. Last but not least, we reviewed the meteor that hit Russia and fascinated observers and astronomers alike.

But 2013 was a very busy year, and there are still things that have to be remembered. For example:

6. Life Can Be So Hard

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Lake Vostok in Antarctica

Humanity has not yet found a planet with living organisms in it, because conditions can be very harsh and inhospitable, unlike in our planet. Or maybe not.  I’m talking about Lake Vostok, in Antartica, where this body of water rests under 500 metres of ice, under extreme temperatures and pressure, and where no sunlight can reach. Immediately, you’d think there can be no life here, but a team of Russian scientists proved last year that there may be, when they drilled through all the ice and extracted a sample of water that contained pieces of DNA.

If life is definitely found, it will most probably be single-celled organisms, not macro-organisms such as fish or sharks, although if there’s anything we’ve learned from this adventure is that life can be found in the most unprecedented places, not matter what form it takes.

7. The Memory of the Smell of Fear

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Memories travel generations in rats

A study carried out last year showed that memories can be transmitted from one generation to the next, and not by talking about it. The case was that a group of rats were subjected to the smell of cherry blossom, and after this, gave them an electric shock, so every time they smelled this, they would become wary and tense. Then, these rats were reproduced, and, surprisingly, the children also became alert when detecting the smell.

Although the mechanism is not yet understood, it may have something to do with changes in the DNA (like switching on and off certain genes) due to chemicals being released in your body.

This phenomenon can happen with other events, not just smell, but others are more difficult to track, since there are a lot of genes involved. Smell, specifically cherry blossom, is easier because there are specific receptors that react to this smell, which scientists already know about, so changes in these can be seen easily enough. Also, its not only the fact that the offspring must remember the smell, but also the feeling that comes with it, fear.

8. The Oldest DNA

In a cave 30 metres below ground, a paradise for archaeologists lies. There, the oldest genome ever discovered has been processed, yielding incredible results.

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Denisovian Hominid

This fantastic place is the Atapuerca cave, found in Spain (my home country), and has always been considered a gold mine for anthropologists. It continues to meet its expectatives, as in a shaft, they found the remains of 28 hominids, of which a thigh bone was extracted. Although extracting a good sample of DNA from such an old sample, especially in a warm climate, is very improbable, scientists tried anyway, and thank God they did. The genome found is 400,000 years old, twice the age of our current species. The surprising thing about his genome is not only its antiquity, but also that it shows the bones found in the shaft known as ‘the pit of bones’ is not Neanderthal, but of a different species of humans called Denisovan, of which very little is known. But with this discovery, maybe we will find out all we need to know about them, and complete the puzzle of our many ancestors.

9. The Most Crowded Trench 

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Mariana’s Trench, the deepest point on Earth

Director James Cameron, known for movies such as Titanic, Avatar or The Terminator, will be remembered by the scientific community for more than his movies.

Last March, he organised the Challenger Deep expedition, which travelled 11000 metres underwater to the lowest point of Earth, the Mariana’s Trench. He stayed there for about an hour, collecting samples and recording everything he saw.

Although the area was not teeming with macro-organisms, unfortunately for Cameron, samples from the submarine show there were unusually high levels of bacteria in the water. For every cubic centimetre, there were 10 million bacteria, a surprise for scientists because the amount of organisms down there was higher than in shallower areas, where conditions are less hostile. A possible explanation is that trenches are extremely good at collecting ‘food’ (organic matter from creatures above), so bacteria would have enough material to survive, even though the pressure and temperatures are not too comfortable.

 10. Blob of Pitch Falls

Pitch, a substance that makes up petroleum, is also one of the most viscous substance known to man, and its qualities can be quite interesting.

Decades back, someone in Trinity College Dublin set up an experiment that consisted in adding a measure of heated pitch to a glass funnel, and then let gravity do its job. The original version of this experiment, however, was done in University of Queensland, Australia, by Thomas Parnell, whose objective was to show and measure how viscous this liquid really was, though he died before it could actually happen.

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The Pitch Experiment

But it was in Dublin where the magic really happened. After years of the pitch standing abandoned in an old shelf, scientist Shane Bergin found it, and after figuring out what it was, set up a web cam and connected it to the Internet so everyone was able to observe the liquid, in case a drop fell. And that is precisely what happened, the 11th of July, after years and years of patience. Although the real purpose has been completed, the web cam is still connected, and it is expected that in the next decade, another drop falls, so be attentive.