Tuesday, 20 May 2014
Physicists from Imperial college London have devised a simple yet ingenious experiment to finally verify the Breit-Wheeler pair production theory. This theory has been around for nearly a century, scientists have assumed its truth but as with all theories they must ultimately survive experiment. The Breit-wheeler theory proposes that if two highly energetic photons (particles of light) collide they can produce an electron- positron pair. This pair production is one of the simplest ways in which the universe can convert light into matter, thus it carries importance in tackling problems of how matter actually came about during the early universe.
The experiment consists of two important parts. Firstly electrons are accelerated to near light speed and focused into beams using high energy lasers, these beams then become incident on a gold target which allows the electrons to pass through but they become deflected. When a particle becomes deflected it loses some kinetic energy, this loss of energy, in the case of electrons, turns to high energy gamma rays which are extremely high energy photons.
These photons then travel through the Hohlraum, which has been made into a thermal radiation field through the firing of high energy lasers on the gold cans surface creating photons similar to that of stars, the photons from the first part then collide with the photons created from the radiation field. This collision will then produce electron - positron pairs which can then be detected using simple electromagnet equipment.
The ingenuity of this experiment is the use of the thermal radiation field which is used in plasma physics, the team at Imperial realized that the hohlraum could be used in creating a photon - photon collision. Now a race to build and carry out this experiment is on. A nobel prize surely awaits the theorists and experimenters.
Saturday, 10 May 2014
A video titled 'Look Up' created, performed and directed by Gary Turk has caused quite a stir in the online world for implying the idea that social media is detrimental for our mental health. The video has reached ~34 million views and has a 255000: 8000 like to dislike ratio, which indicates that Turks claims have hit home.
The description of the video contained this interesting claim:
[We live ] in a world where we continue to find ways to make it easier for us to connect with one another, but always results in us spending more time alone.I believe, and many other people believe, that Turks claims hold some ground but I want to know specifically why they would hold any truth value at all. So we have to translate this claim into an hypothesis or something we can analyse using scientific reasoning so that we can try to work out the cause of this phenomenon.
So Turk's claim could be put like this:
Humans have developed (and will continue to develop) social interfaces which reduce the amount of energy needed to communicate valuable information. These social interfaces correlate with symptoms of loneliness.
It is quite obvious that typing or using a headset is much cheaper, in terms of energy, than talking or socializing with someone. For instance I could send my friend a message on facebook which would require my brain, fingers and some fibers in my arms to work and consume calories. However if I were to actually talk to my friend I would use my hands, arms, facial muscles and brain which would consume more calories and we have not yet taken transporting my body to find my friend into account. Even on the internet apps can make communicating much easier.. with predictive text, snapchat (click of a button) etc.so it is fair to say we are making communication much easier in terms of energy.
This wasn't the contentious part. The contention is the correlation between making communication (linguistically) easier and loneliness. For us to understand this claim we have to take note of the differences between real human interaction, which I will call RHI and social media interaction which I will call SMI. Well during RHI you can see, feel, smell and hear the body of the persons you are communicating with. For example when I am talking with a girl, I subconsciously smell her distinct pheromones, her body language towards me (if she is close, closed, open or far etc.), her eye contact, the way she stands and any touching involved (steady on there). All these sensory inputs are used by our brains as indicators for sexual attraction, if they are friend or foe and how we measure up to them in terms of social status etc. our brains have evolved to do this. However in SMI we do not have most of these sensory inputs. I say 'most' because on apps like skype we can see the faces of people and gather information, but we miss other major sensory inputs. On the extreme ends of SMI, like texting or whatsapping, there is minimal sensory input. However on SMI we can use videos, memes, funny emoticons and different txt speak to communicate information on how we feel and so on.
The important difference between RHI and SMI is the sensory indicators that we have used for thousands of years and our human and chimpanzee ancestors have used these too albeit differently. They provided us with clues which increase our potential to mate, which is important for the survival of our genes through time, or for our inclusive fitness. For example a female who doesn't show signs of attraction by not twiddling her hair or something of this nature we could save energy by stop trying to 'woo' her and try a different female. This saves energy, time and makes our efforts to reproduce more effective. Also social interactions can distinguish between threatening and non-threatening behavior without a complicated linguistic language.
So because social interaction is good for our inclusive fitness it would seem useful for our brains to reward us for doing so, this makes us do more. How can our brains do this and tell when we are actually socially interacting? Well the sensory indicators are unique to social interaction so when our brains receive these sensory signals it can also release endorphines or other chemicals which make us happy and good. This can also happen the other way... it would benefit our genes fitness to 'punish us' when we are not being sociable i.e. to feel lonely so that our brain will think we need to do more social interaction.
But as modern humans developed a complicated and more precise language more emphasis (by evolution) was put on developing areas of our brain which dealt with linguistics. Fast forward to modern day world where we have a greater population, bigger social circles and less time to socialize (with work, learning etc.) a demand for time and energy saving communication came about. This demand was first met with letters, then the telephone... morse and so on and so on until we get to the great internet. We still use our sensory indicators of course. But what we have witnessed is that the evolution of SMI has happened quite fast and has strayed further away from normal humal interaction i.e. RHI.
Our bodies still only think (have been genetically programmed to think) that social interaction is only happening when we have the sensory indicators and so on. However as SMI has strayed further away from RHI our bodies have not adapted quick enough to know that using SMI is also social interaction. This means our brains will perceive the situation that we are not socializing and will go into punish mode. This could be why we all perceive to be lonely when in fact we are not, it is just that our bodies do not know this. This is only because cultural organisms (ideas, memes etc.) evolve faster than human beings. The evolution of memes is completely different to genetic evolution. This fundamental difference could be the root of the problems we face and could face in the future.
|This is not the case.|
So Gary Turk makes a valid point. The fast evolution of SMI could pose a problem for us if it keeps straying away from RHI. However we could develop technologies which simulate the sensory indicators of RHI which tricks our evolved brains into thinking that we are taking part in RHI but using SMI and therefore produce the chemicals etc. which rewards us for socially interacting. A good compromise.