Scientific American: What is “anti-science”?

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Source: Science

Being “anti-science” does not mean that denying the benefits of scientific research or the validity of scientific methods. We can’t do anything but feel helpless or ruined to see Trump’s government’s recent policy changes in science (e.g. cut of EPA and NASA budget, anti-vaccine stance, downplaying of climate change). People in United States started a March for Science movement to “call for science that upholds the common good and for policy makers to enact evidence based policies in the public interest.

In light of such sentiment, we can’t emphasis enough the importance of upholding the integrity and value of scientific research, especially when it comes to policy making process which affects the lives of millions. We need, however, to revisit the definition of “anti-science”.

As highlighted in a recent Scientific American article, the attitudes towards science cannot be divided clearly to two opposing sides “pro-” and “anti-science”. Human behaviour is more nuanced. It is more appropriate to address anti-science as denial of certain scientific issues. One that agrees with vaccination may deny the evidences of climate change. Psychologists call it motivated biased, which means we treat facts to reinforce our beliefs instead of convincing ourselves the otherwise is true. In short, we like to twist facts.

As the information is getting more accessible and easily retrieved and shared, people are likely susceptible to form “echo chamber”, be it on Facebook, Twitter or other social media. We seek out information that supports ourselves, and refuse or outright deny evidences that oppose to our beliefs. As called “motivated reasoning“, we are all tribal creatures.

Another interesting point brought up by the article is that people do not deny the scientific facts themselves, but the implication of solutions to the problems unsurfaced by the facts. Let’s say climate change. If the climate change is true, the implied solutions are to reduce the reliance on fossil fuel, to cut down the consumption of diary products and to invest in renewable energy industry. When confronted with a change of habit, human are very unlikely to change. It is called solution aversion.

So for us who wants to make a change, please keep an open mind. Understand the different backgrounds of the audience, and try to motivate them from the root cause.

Endless energy generated by evaporating water on charcoal

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No, not this way! (source)

Minor corrections: It is not endless (the generation needs constant water supply), and by charcoal I mean nano-structured carbon layers. Still, it is impressive to see how a simple physics phenomenon could give rise to an important application: producing electrical energy. A group of scientists from China published a paper on the topic in Nature Nanotechnology Letter last month.

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Water molecule. (source)

Water is a molecule composed of 2 Hydrogen (H) and 1 Oxygen (O) atom, and collectively they behave slightly ionic – there are H+ and OH- ions in the system, for example a cup of water. When the water on the carbon surface evaporates, it will induce a force to pull water through the tiny channels in the carbon layers. An usual piece of carbon is hydrophobic, meaning it repels water and stops the action pretty much.

The scientists found out that by treating the carbon to heat and plasma, the surface will be a mixture of carbon and oxygen compounds, and turns into hydrophilic surface. That is, water-loving oxidised carbon. Hence, the water gets pulled through the channels and evaporates at the other end at a steady rate, provided the vapour pressures at both sides don’t change.

How does it produce electricity then? Remember we mentioned earlier: the water contains ions, and a stream of water in motion is a current, carrying minuscule but measurable electrical charge. Ta-da, we produced electricity!

The scientists further found out the voltage produced can reach up to 1 V (high enough to light up an LED), and can be turned on and off by opening and closing the box in which the experiment is contained. This cheap, controllable way of producing electricity from evaporation of water could lead to very practical uses in real life, such as power generation at rural areas or places with little sunlight.

Original Paper

Five more years for Hubble Telescope

Source


Hubble Telescope will serve 5 more years in the Space, thanks to NASA approval recently. It will continue to send us wondrous images of space, along with James Webb Space Telescope scheduled to launch in 2018. Two eyes are better than one, aren’t they? 

Hubble will be deorbit and fall to Earth after its extended lifespan, so expect a firework around that time. 

How to measure speed of sound in toilet! (or, not to)

It occurred to me that science can happen any time, anywhere. Before we got ready for a jog yesterday, my friend and I made a few funny sounds in our changing room a.k.a the glorious toilets. Suddenly the sound got louder than expected, it amplified in some sort of ways.

Curious enough, we were thinking all the possibilities. Somebody playing a prank in the next cubicle? Or we stumbled upon the dark secret of the toilet? Or it is because of science? Our best educated guess led us to standing wave – our sound waves travelled between the two walls of the toilet cubicle, forming loud and quiet regions along the way.

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Red & Blue: waves. Black: wave+wave.

Of course, an answer often leads to more questions: what can we do with it? It happens that the width of the wall is related to the speed of sound and the pitch of my voice.

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Simple & crude.

If I know my pitch and the width of the wall, I can measure the speed of sound! With this realisation, I readily set out to a new challenge:

Width

It was measured to be 70cm.

Pitch

I did a recording of my sound in the toilet (for science!):

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My sound.

You might hear the sound gets louder as the pitch goes lower.

To find out what the dominant frequencies are, I did a voodoo on the sound file (essentially performing a Fast Fourier Transform) using R.

 

In the last image, you can see the dominant frequencies peak at ~115Hz. That gives me a value for speed of sound : 161 metres per second. Which is half of the expected answer (340 metres per second). What a bummer :/

Lesson learnt:

  1. As the sound propagates in three dimensional space, the formula I used is not suitable (2D case only).
  2. I didn’t consider the sound might form standing wave with the floor and the open ceiling as well. All sorts of weird interactions (diffraction, interference etc) were not included.
  3. My voice was far from perfect and produced pitches of different magnitudes which complicates the issue.
  4. Science can be observed everywhere if you look hard enough. Just make sure to grab a friend with you. Silly things are better with friends. 😉

 

Slicing brain piece by piece

Imagine your brain being sliced by a razor into thin pieces of tissues – such mere thought elicits extreme pain to us. Yet, neuroscientists do that. Behold the action done in University of California, San Diego:

Our delicate and jelly like brain, weighing about 1.5kg for an ordinary adult, is precisely cut into 2000 slices, each as thick as a fine hair (70-microns). Each slice is painstakingly stained and photographed. All the scans are available online at the Brain Observatory. The digital library of brain helps researchers and doctors understand our brain better by providing an extremely detailed map of the brain (0.37 micron per pixel). The scientists are not limited by the blurry images typically taken in an MRI scan and able to pinpoint locations in the brain. This is a huge upgrade!

Apart from the obvious usefulness in research, the team also hope that the act helps “humanise” our brain. By understanding our brain better we could care more about the relevant topics. Each brain collection comes with biography, interviews and media that help us understand the person as a human (up to the individual’s agreement). Science communication is a challenging task – how do we make people care and engaged for the issues we try to get across?

Dr. Jacopo Annese shows off a 3D model of Henry Molaison’s brain. Kate Shaw, Ars Technica, http://arstechnica.com/science/2015/03/stepping-into-the-digital-brain-library-the-google-earth-of-neuroscience/

What colour is this dress?

This dress has been raving on all sorts of social media today, posted//tweeted/shared by all your friends. They all ask a simple question: What colour is this dress?

Most people say it is either Blue/Black or White/Gold, and some may even claim that it changes depending on the time, weather, lighting, temperatures, handedness and so forth. Why is it so?

There are a lot of explanations offered on the internet now (Wired, Reddit 1, Reddit 2, Reddit 3), and I bet you can find the explanation that suits your taste the most. Yes, there is no conclusive answer to this so far, and my favourite answer is the colour constancy effect. It basically says that the colours we perceive depend on the context and illumination of the surrounding.

Look at these 3 photos under different white balances:

The middle is the original image. The left one has white balance on white, and the right one on blue. (Wired)

By changing the white balances, we can see the colours changed drastically. Our brain needs a reference point (white base) to tell other colours. The ambiguity in choosing the reference point makes our brain choose either side of the story, or in our case, of the dress.

There is an excellent illustration on Reddit that shows how different illumination may change the colour:

It can be either a black or white dress depending on the light!

A relevant optical illusion, also a favourite of mine, is this:

Checker shadow illusion. Or in today term, 50 shades of gray illusion.

What are the colours of tile A and B? Are they the same shade of gray? You can find out the answer yourself 🙂

After a long hiatus… and a short lesson about Newton’s third law

It occurred to me that I have not been writing for a long time. I would like to blame it on my busy schedule and inconsistent attitude in writing. Things changed and situations shifted in the last year, but I digress.

So I attended this course “Work in a Team” at Kaplan these two days. One of the activities we were asked to do was to draw something on a piece of A4 paper. We were free to draw anything we want, so here it is mine:

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The end result is not very surprising. In your subconscious mind, you will just draw what you have in mind the most. It shows my nerdy side of Physics! This illustrates Newton’s Third Law of Motion in which states that for every action there is an equal and opposition reaction. If you slap on the table, your hand will feel the pain too, don’t you? In this painstakingly drawn diagram, the first skater pushes the other (action) and in turn a reaction is exerted back on the first skater. The end result? The two skaters push each other away despite that only the first skater pushed actively.

Looking back to the course, it somehow translates to a teamwork environment. If we keep pushing people to a specific goal we will end up getting further from it. If we force people to do things, those might not be get done in the end. The worse is that the relationship between you and the person might turn sour as well.

What’s the better way then? Instead of pushing, why not pulling him/her closer to you and move towards the common goal together? It is just like pair skating, isn’t it?