Posts

In 1990, we launched the Hubble telescope into orbit as the first sophisticated orbital observatory. This was an incredible achievement, but also allowed us to study things never before possible. The high resolution spectrograph allows us to observe and record ultra violet waves that could never make it through the earth’s atmosphere. This is hughely impactful to our observations and allows us to see the universe clearer than ever before.

Upon its launch, the telescope was malfunctioning and ineffective at making precise recordings, but through multiple missions and spacewalks, the telescope was fully functional and meeting its full potential. With fully functioning parts, we were able to make some remarkable discoveries. Through the observation of nearby cepheid variable stars, we were finally able to make an accurate calculation of the Hubble constant. While this had been estimated previously, we now had a reasonable calculation of the universe’s rate of expansion. Not only did we find values of important constants, we were able to get a clearer picture of the universe’s history as a whole. In the Hubble Deep Field, a photo including over 1,500 galaxies, we saw some of the “story” of the universe.

Hubble Ultra Deep Field | ESA/Hubble

Hubble Deep Field

This telescope was a huge success. It far outlived its expected lifespan and brought numerous incredible discoveries to mankind. So yes, the Hubble telescope was potentially the most important advancement in the study of the universe to date. Now the James Webb has taken over the mission and we can fully appreciate the impact the Hubble space telescope had on our understanding of the universe today.

God particle and physicists’ grail, what is the Higgs boson and why is it so important?

 

What it is?

Le Higg’s boson is elementary particle postulated in 1964 by three researchers, two Belgians, François Englert and Robert Brout, and then independently by the Scotsman Peter Higgs, even if history has only retained the name of the latter.

To summarise its function, it has often been said that “The Higgs boson is responsible for the mass of everything around us”, a shortcut that needs to be deciphered

Why do we need Higg’s boson?

The Standard Model of physics postulates that in the Universe, all the phenomena that surround us are the work of four elementary interactions, fundamental forces: the electromagnetic interaction (to the origin of light and magnetisation), the gravitational interaction, the strong nuclear interaction (explains the very cohesion of the nucleus of the atom) and the weak nuclear interaction (explains the radioactivity of certain atomic nuclei).

Even though there are four different forces, physicists are trying to unify them in order to arrive at a Theory of everything.

The electromagnetic interaction and the weak nuclear force, for example, are unified in the form of an original force that links them: the electroweak force. Except that to bring them together in this way, the Standard Model ‘theory of everything’ faces a big problem. Each force has its own type of elementary particle.

The electromagnetic force is associated with the photon, while the weak force is associated with the W and Z bosons. This is where unification gets stuck: the expected symmetry is broken, because the photon has zero mass (hence the possibility of a “speed of light”), which is not the case for the very massive W and Z bosons. How can the theory of unification be sustained in the face of forces that are so different with respect to such an essential ingredient as their mass? This leads to several questions like how to take mass into account or explain the fact that different particles have different masses.

The Standard Model, already included all types of elementary particles such as quarks, leptons and bosons.

Figure 1:Ordinary matter content of the Standard Model of Particle Physics.

 

The protons and neutrons inside the nucleus of the atom are made up of quarks. The more familiar leptons are the negatively charged electrons outside the nucleus. Bosons are responsible for various energy fields such as electricity and light. But none of these particles explain the mass.

In 1964, the theory of the Higgs field was postulated to solve this problem.

 

Higgs field

To understand the mechanism of Higgs field, we can compare it to a group of people who initially fill a room in a uniform way. When a celebrity enters the room, she draws people around her, giving her a large ‘mass’. This gathering corresponds to the Higgs mechanism, and it is the Higgs mechanism that assigns mass to particles.

It is not the boson that directly gives mass to the particles: the boson is a manifestation of the Higgs field and the Higgs mechanism, which gives mass to the particles. This is comparable, in this metaphor, to the following phenomenon: an outsider, from the corridor, spreads a rumour to the people near the door. A crowd of people forms in the same way and spreads, like a wave, across the room to pass on the information: this crowd corresponds to the Higgs boson.

In a more physicist way, the Higgs field is everywhere and it has an effect even in the most total vacuum of space, it gives mass. Since the quantum vacuum is full of the Higgs field, aligned along a particular direction of the abstract space mentioned above, particles “parallel” to this direction will be able to propagate without constraint, but those “perpendicular” will suffer a slowdown due to the incessant interactions with the Higgs field.

 

Origin of the universe:

According to this theory, The Universe would be filled with a specific field that gives mass to elementary particles. This field was present at the Big Bang, but it was zero. The force bosons were therefore also empty of mass – including the W and Z bosons. As the Universe cooled, it spontaneously became charged. All the elementary particles that interacted with the Higgs field acquired mass, and the longer the interaction lasted, the higher the mass turned out to be. The photon did not interact with the field because of its nature, so its mass is zero; but the W and Z bosons interacted so much that they got their mass.

 

The theory looks good on paper, but to be proven, it must be observed. The fields of the Universe are all manifested, when they exist, by a visible particle. In the case of the Higgs field, this particle is called the Higgs boson. Only one thing was missing: to detect it.

 

Some words about the LHC:

Figure 2:The tunnel and part of the particle accelerator at the Large Hadron Collider

The existence of the scalar boson is too short to detect it directly: we can only hope to observe its decay products, or even the decay products of these. Events involving ordinary particles can also produce a signal similar to that produced by a Higgs boson.

Thanks to the Large Hadron Collider (LHC), the particle accelerator that started operating in 2008 near Geneva. In this 27-kilometre long circular tunnel, protons are accelerated very quickly, raising their mass very high and producing collisions – an ideal tool in particle physics. It is possible to recreate conditions similar to the primordial environment of the universe.

Two parallel LHC experiments, the ATLAS and CMS detectors, have detected a boson in a mass region of the order of 126 GeV, exactly where the Higgs boson was expected to be. It could be nothing other than the long-sought particle that proved (fifty years after the theory emerged)  the existence of the Higgs field.

The experimental proof of the Higgs Boson led to the award of the Nobel Prize in Physics to François Englert and Peter Higgs in 2013.

 

To conclude, the impact of this discovery is huge as it clarified the Standard Model of physics and further confirmed the idea of a unification of forces. Knowledge of the Higgs boson’s properties can also guide research beyond the Standard Model and pave the way for the discovery of new physics, such as supersymmetry or dark matter.

 

References:

Le boson de Higgs. (n.d.). CERN. https://home.cern/fr/science/physics/higgs-boson

Universalis‎, E. (n.d.). BOSON DE HIGGS. Encyclopædia Universalis. https://www.universalis.fr/encyclopedie/boson-de-higgs/3-champ-de-higgs-et-masse-des-particules/

Pourquoi se préoccuper du boson de Higgs? (n.d.). Parlons Sciences. https://parlonssciences.ca/ressources-pedagogiques/les-stim-en-contexte/pourquoi-se-preoccuper-du-boson-de-higgs

Images:

Introduction to Physical Astronomy – Elementary Particles. (n.d.). Kias.dyndns.org. http://kias.dyndns.org/astrophys/particles.html

Pourquoi se préoccuper du boson de Higgs? (n.d.). Parlons Sciences. Retrieved May 13, 2022, from https://parlonssciences.ca/ressources-pedagogiques/les-stim-en-contexte/pourquoi-se-preoccuper-du-boson-de-higgs

There are three main ways to get faster on a bike; get stronger, get a lighter bike or become more aerodynamic.

 

Since getting stronger is hard and a lighter bike is expensive, the easiest way to go faster on a bike is by optimising aerodynamics.

 

One component of drag is the difference in air pressure in front of and behind you. Shapes are developed by using computational fluid dynamics (CFD) and wind tunnels. The most aerodynamic shapes are often these teardrop-shaped “aerofoils”, and these shapes influence the design of helmets and the tubes that make up the bike frame.

 

A popular joke in CFD is the aerodynamic cow, here the colours indicate the intensity of the wind drag.

 

Some designers have even used the CFD simulation heatmap to inspire the bike’s livery

 

The force of wind drag can be calculated by the following equation

Where ρ is the air density, A is the frontal area, C_D is the drag coefficient and v is the velocity. This means that at higher speeds the drag force increases a lot. Since we’re trying to go fast anyway, this doesn’t matter. The most important variable here that is easiest to manipulate is the frontal area. A cyclist wants to make their frontal are as small as possible to decrease drag. They can manipulate this by simply using a bike that is designed to be more aerodynamic, with complicated carbon layups that incorporate aerofoil shapes into the leading edges of the frame and with deep section wheels that decrease turbulence of the wind as it passes by the wheels. But the easiest, and cheapest way to decrease frontal area is to bring your elbows in or lean forward more.

 

 

The third cyclist in the figure is the most aerodynamic but is also the least equipped to delivery power into the pedals to propel themselves. Hence, this position is usually only adopted when they are going so fast that the cyclist is no longer able to pedal at a cadence that actually makes them go faster, having to rely solely on aerodynamics to gain more speed. Because of this, many different variations of the “supertuck” have been developed by prominent cyclists.

 

 

In 2021, the Union Cycliste Internationale, or UCI, the governing body of professional cycling banned the “supertuck” position (sitting on the top tube, as seen in the “Froome” and “Top tube safe” positions) from races, deeming it too dangerous and unsafe. An even more extreme and dangerous method of reducing frontal area can be seen in the following video.

Cymatics are a subset of vibrational phenomena which describe the motion of a material under a vibrational signal. Typically a material i.e a liquid, paste or group of particles are placed upon a plate of arbitrary shape. Different shapes are formed by the material as the surface of the plate is vibrated. The nature of the shape depends on the geometry of the plate and the driving frequency of the vibration.

 

The phenomena was observed by notable scientist Robert Hooker in 1680 as he saw nodal patterns emerge in flour when applying a vibration across a glass plate. This method was improved upon by German Musician and Physicist Ernst Chladni. He noticed that the vibration could be used to visualise the resonance of musical instruments. He achieved this by drawing a violin bow across a plate covered with a fine dust (sand/flour) until the plate reaches resonance. The phenomena observed can be explained using classical physics. When the plate is vibrated, the dust will always travel to a point of zero vibration. This is because the dust follows the path of standing waves along the nodal lines of the plate. The dust will move away from the antinodes, where standing wave amplitude is at a maximum, and toward the nodes where standing wave amplitude is at a minimum. These form the patterns known as Chladni patterns. These can take many different shapes depending on frequency mode and plate shape

 

Two Chaldni patterns on the same plate under different frequency modes

 

The applications of Cymatics and Chladni patterns present a huge potential in the fields of contemporary music and art. For example, the 2022 Eurovision competition uses Cymatics in its logo and poster.

The principles of formation of Chladni patterns can also be extended to liquids and dusts in 3-D orientations. The following video is a perfect example of such, and the fusion of science and music.

 

Cymatics are certainly an interesting facet of physics that shows the link between sound and vibrational motion.

 

  1. Pg 101 Oxford Dictionary of Scientists- Oxford University Press- 1999
  2. Forrister, How do chladni plates make it possible to visualize sound, COSMOL, 2018

When it comes to science and the supernatural, the common consensus is that the two areas are polar opposites and will never meet. The area of quantum mechanics, which is approaching the ripe old age of 200 years, continues to provide a great deal of confusion within the scientific community as to what it is that makes such an utterly baffling concept possible.

Quantum in a Nutshell

Quantum mechanics is, at its core, an explanation of why particles act the way they do. In classical mechanics a wave will always act like a wave, that is, it will always travel at the speed of light with some frequency and respective wavelength and will experience effects such as refraction, reflection and diffraction. Similarly, a particle in classical mechanics will always act like a particle; a solid mass with a momentum. Quantum mechanics is used to explain the motion of particles that are so small they do not act like a particle or a wave, but rather as both.

Now you may be thinking “big deal, particle go brrr” but I can assure you it gets weirder. In order to illustrate why the scientific community was and remains to be so perplexed by this field, we must first observe the results of the double slit experiment, the first example of wave-particle duality.

The Double-Slit Experiment

First performed by Thomas Young in 1802, the double slit experiment, as the name suggests, uses two slits in the surface of a solid material to create and interference pattern from an incident beam of light. This experiment was revolutionary in observing the physical properties of wave motion.

Figure 1: Young’s Double Slit Experiment. Credit: [1] eiu.edu

In 1927, in an experiment performed at Western Electric by Clinton Davisson and Lester Germer, it was proven that electrons could undergo diffraction and produce a diffraction pattern, thus proving the hypothesis of wave-particle duality, a fundamental building block of modern-day quantum mechanics. In 1961, the double slit experiment was carried out using a beam of electrons instead of light in order to see if they would produce the same result. Sure enough, the electrons produced an interference pattern on the screen.

So Young’s experiment shows us that electrons behave like waves. But we know that electrons interact with other particles in the same way a particle would. This wave-particle duality is what gives rise to the quantum-mechanical theory. An electron may act as either a particle or a wave at any given time. The real question is does an electron know when it has to act like one or the other? A common thought experiment details a detector being placed at the two slits so that the electron is observed going through the slit. Hypothetically, the interference pattern would not appear on the other side as before since the electron is observed passing through the slit in the form of a particle and therefore must continue to act like a particle. Richard Feynman used this thought experiment to prove that an electron must always act like a wave in this circumstance since this thought experiment cannot possibly be performed due to the impossibly small scale ([2] Harrison, 2006).

Varying Interpretations

Feynman’s thought experiment can cause some confusion as it gives the impression that an electron could choose to act like a particle at the slit because it somehow knows it is being observed. Similar to other natural phenomena, if left unexplained by physics, many will jump to believe that a higher power could control such behaviour. Science has always been used to explain natural phenomena that were previously considered to be acts of witches, gods or the supernatural.

The idea that a particle could be granted some form of consciousness by a higher power is something that would very much excite those who believe in or are searching for a god. Simply put, however, that’s not how it works. The particle does not “choose” its state, it simply is. If placed in a certain condition where a wave will experience a certain effect (as in the double slit experiment) it will do so and will undergo the same process as anything else with wave motion. Like when a non-Newtonian fluid is put under stress, it will alter its form to adapt to its surroundings. An electron is still a particle but simply acts like a wave sometimes.

The probabilistic nature of quantum mechanics does give rise to some theories about alternate worlds in which fundamental particles were to act like particles where they would act like waves in our world. This “Many Worlds” theory is more the stuff of science fiction as there is truly no way for it to be proven. The fact that it cannot be disproven, however, is an interesting notion that finds itself appearing more in cinemas than in the lab.

The Final Message

The scientific community’s interpretations of quantum mechanics vary from the perfectly normal to the apparently bizarre. The notion that this field of study could prove the existence of parallel dimensions seems to be pulled directly out of science fiction. The idea that a particle can choose its state of being gives rise to a plethora of philosophical and potentially religious questions.

Quantum mechanics is clearly the most vital area of physics today and the sooner we can come to an explanation that can be understood by all, the better.

 

References

[1] Dr. Doug Davis, Adventures in Physics, 20.2 Young’s Double Slit, East Illinois University. https://ux1.eiu.edu/~cfadd/3050/Adventures/chapter_20/ch20_2.htm

[2] David M Harrison, 2006, The Feynman Double Slit, Dept. of Physics, University of Toronto. https://faraday.physics.utoronto.ca/PVB/Harrison/DoubleSlit/DoubleSlit.html

The northern lights, also known as aurora borealis, are stunning luminous phenomena visible in the north pole region of the planet. In the south pole, they are called southern lights or aurora australis. The colorful dance of these lights in the night sky has fascinated humans for millennia. If once thought of as spiritual entities, today, the physics behind these magical events can be explained.

Figure 1: The Northern Lights, Alaska, night of Feb. 16, 2017. Credit: NASA/Terry Zaperach. [1]

The name aurora borealis was coined by the Italian astronomer Galileo Galilei in 1916 after Aurora, the Roman goddess of dawn, and Boreas, the Greek god of the north wind. The earliest reliable account of the aurora borealis comes from Babylon, in an astronomical notebook dated 567 B.C. The babylonian recorded to have seen a “red glow” on the night of 12/13 March. This observation, which is part of a series of astronomical events, occurred when the geomagnetic latitude of Babylon was about 41°N compared with the present value of 27.5°N, giving reasons to believe in a higher auroral occurence in 567 BC than at present on the territory. In the 20th century, the Norwegian scientist Kristian Birkeland theorized a scientific explanation for this phenomenon. The display of coloured lights is a consequence of the interaction of the solar wind with the Earth’s magnetic field and atmosphere.

The Earth is considered to be approximately a magnetic dipole, with a magnetic South pole (geographic North pole) and a magnetic North pole (geographic South pole) [Fig. 2 ]. The Earth’s magnetic field forms an envelope around our planet, the magnetosphere, and its strength varies roughly between 25,000 – 65,0 nT (0.25 – 0.65 Gauss) depending on its direction and distance from the Earth’s surface. The magnetosphere protects the planet from high-energy particles coming from solar winds.

Figure 2: Earth’s magnetic field. [2]

The solar wind is produced from plasma material escaping from the Sun’s corona (outermost atmosphere). The plasma at the Sun’s surface is heated continuously, up to a point where the Sun’s gravity can no longer hold it down. Strong solar eruptions, called solar flares, and coronal mass ejections produce streams of high energy particles which flow through the solar system reaching the Earth. Here, electrons and protons are drawn into the magnetic field, moving along its field lines towards the poles. Since the Earth’s magnetic field enters and exits the planet from the poles, the protection from high energy particles at the North and South poles is reduced. High energy particles are hence able to penetrate within the atmosphere. In the region between 100 and 500 km above the ground, the aurora forms.

Figure 3: Interaction between solar wind and Earth’s magnetic field. (Credit: NASA). [3]

Electrons from solar winds collide with oxygen and nitrogen gas in the ionosphere and knock electrons out of their shells, forming excited ions. The oxygen and nitrogen ions will release energy in the form of light to regain a stable condition. The aurora colors depend on the wavelength of the light emitted and hence on the type of gas that is excited. For instance, atomic oxygen (O), which is present in the higher layers of the atmosphere, is responsible for the red color, whereas molecular oxygen (O2), present in lower atmosphere layers, is responsible for the most commonly seen green color. Nitrogen is hit more rarely and produces pink and dark red light.

Figure 4: Colorful aurora taken in Delta Junction, Alaska, on April 10, 2015.
Credit: Image courtesy of Sebastian Saarloos. [4]

Reference:

[1] https://climate.nasa.gov/news/3105/earths-magnetosphere-protecting-our-planet-from-harmful-space-energy/

[2] https://commons.wikimedia.org/wiki/File:Earths_Magnetic_Field_Confusion.svg

[3] LAGRANGIAN COHERENT STRUCTURES IN IONOSPHERIC-THERMOSPHERIC FLOWS – Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Solar-wind-magnetic-field-interacts-the-Earths-magnetic-field-Credit-NASA_fig6_326622449 [accessed 12 May, 2022]

[4] https://climate.nasa.gov/news/3105/earths-magnetosphere-protecting-our-planet-from-harmful-space-energy/

[5] https://www.britannica.com/science/aurora-atmospheric-phenomenon

[6] https://www.asc-csa.gc.ca/eng/astronomy/northern-lights/default.asp

 

A discussion on the responsibility of the scientific community.

 

Since the dawn of time man has sought solutions to problems of all kinds. This is a fundamental aspect of human nature, to seek solutions to problems. We humans are an inquisitive group as beings go. Using facts and figures, rigorous theoretical and experimental methods to help us understand the world and its issues. Often in the hopes of being able to use this understanding, to combat problems in our world.

One such issue which is plaguing our life as humans in the modern day is the energy crisis. Global warming, overpopulation, what have you. There are dozens of different ways and permutations of speaking on the same issue. The issue is to simply put, that we have too many people in this world, and this causes issues of not enough food to go around or other factors. However, one of the major issues is that to keep so many people alive and in a decent lifestyle requires quite a large amount of energy. Now of course one may suggest the obvious albeit very immoral solution of culling the herd. Lowering the population or what have you. However, one of the most common things which is brought back to you is that simply the way in which we generate energy in this world is not efficient enough. We are using non-renewable sources, we are burning fossil fuels which is causing an enhanced greenhouse gas effect causing, well I wish I could say, untold damage but unfortunately recent studies by the UN have shown us exactly how telling and dire the results of our current global energy consumption is.

Because of this, we hope to do better. We wish to make a world in which we can survive, and we don’t cause too much damage and with this. We see people focusing on plastics the trash islands in the sea. We see many people scramble and scrape to have individual power sources in their house wind turbines to power themselves so they may be “off the grid” in the hopes of making actual personal changes to help combat this issue, when any scientist worth their salt would tell you that having a larger production plant with more people to manage and more ways to deal with the issues and inefficiencies would be far more environmentally.

Additionally, people talk about non-renewable resources as if they are the devil. Something to be absolutely avoided and although certain non-renewable resources are certainly not great with many being fossil fuels which contribute to the enhanced greenhouse gas effect to say that non-renewable energy sources are inherently bad, or evil is simply untrue.

An excellent example this is the fact that people seem to forget that renewable resources aren’t entirely eco-friendly. Their carbon footprint certainly isn’t a 0 because the simple construction of anything. Involves, for example, the refining and machining of raw materials. Even the breaking down and replacement of certain pieces in the machinery. This all has a carbon footprint this, it has an effect.

It is clear to see that this is a simple example of what would be unfair to call misinformation, but certainly an oversimplification of the issue at large. A great example of the dangers of a misleading oversimplification of this topic. Would be for example that nuclear energy is demonized as it is a non-renewable source.

Which by this simplification should be terrible, however, nuclear energy is clean, although like all things there is an inherent carbon footprint required to create nuclear power plants. But instead let us talk about the dangers, the lack of safety which this source of energy generation poses.

When this topic is raised people will talk for days on end about the dangers of nuclear energy. Speaking of Chernobyl, a truly terrible incident. However, I implore any individual who is truly scared of such things, to look into the current safety of nuclear power plants. They are, for all intents and purposes, highly unlikely to ever meltdown if they’re built to the legal specifications which day are required by in the modern day.

Now historians who may be aware of such things may turn to me and say, “That’s an excellent point however Chernobyl was not build to the specifications they required they took short cuts and in turn it melted down”. I would call this an excellent case of what-about-ism. If you were to assume that nothing in this world was built to the safety specifications given? Well then on ships should be imminent the dangerous all cars be imminently dangerous. Things in this world if they’re not built to specification may well be extraordinarily dangerous.

But if we are to assume that’s safety specifications will be upheld for every single instance of an object’s construction in this world except for one well that’s a very simple way of identifying bias to put it frankly.

But if one were to discuss the benefits of nuclear energy, is it truly making a difference? I would ask for you to look at a very practical and tangible example. Since the unfortunate war which has begun in Europe, people have been talking about the rise in gas prices in Ireland specifically. People have been discussing that in Ireland petrol has increased in price a shocking amount. However, I would ask for you to compare this to perhaps another country which has utilized different energy sources for power generation, specifically nuclear energy. For this example, I chose France.

France is a country which unlike Ireland generates a large degree of it’s energy via alternative means to gas. Notably nuclear energy. One could argue that since Ireland does not import natural gas from Russia that this would not be an issue for Ireland, however Electric Ireland, one of Ireland’s larges gas and electricity supplier’s “plans to increase residential electricity prices by 23.4 per cent and gas prices by 24.8 per cent with effect from 1 May 2022” tell a different story. This is not a large an issue in France once again due to a lesser dependence on natural gas to produce energy compared to nuclear energy.

Nuclear energy which notably unlike oil doesn’t have a primary supplier who is currently going to war and thus for moral reasons people will not purchase oil off of.

 

Graph for representation of point

Figure [1] Energy Generation by fuel source in France

 

Graph for representation of poin

Figure [2] Energy Generation by fuel source in Ireland

 

However, from this example an interesting question arises. Why do we have situations where we as scientists have for lack of better phrasing the correct way to go about things aren’t listened to? Why do we know of the safety and benefits of nuclear energy to the point where there are organizations across the world and Irish example being 18for0, who are essentially campaigning against people such as the Irish Green Party in an attempt to make progress in nuclear energy being introduced in Ireland?

Why do we have it that are Green Party, those who focus on having less fossil fuels, less a carbon emission and a better environmental impact on the world. Why are they against a solution which is entirely viable it is simply because there is a large contingent within that party who are not sufficiently educated on the topic.

In the scientific community today, it would be unfair to say we haven’t made great strides and ideas for the betterment of the world. We have found ways to do good.

However, it appears as though even items as comprehensive and accessible as the UN climate report is not being taken seriously. These things are not being seriously considered and we must ask why.

Why? Why do we have situations where the answers are clear and yet people will not take them. A very recent example of this is the large contingent of anti-mask anti-vax people who refuse to wear masks or take vaccinations for the coronavirus.

This unequivocally caused damage and further spread of this virus. This ignorance killed people. We had individuals, we had scientists, members of our community who went out and attempted to sway the masses attempted to prove to them that these solutions that we knew worked, actually did something to help.

I understand that it is deeply frustrating to know what the right choice is and see many people not make it. That is deeply frustrating, and, in that frustration, it is very simple to throw off your hands and say “I give up because we tried our best and they just wouldn’t listen to us, so it’s their fault not mine that we are in the bad situation we are”. That the misinformation the “Facebook facts”, if you pardon the phrasing, are too much and we cannot seem to go a day without seeing. We have done studies we are aware that false information spreads faster than correct information.

Does false information spread easier because it is more eye-catching, because it is easier to understand because it is not phrased in complicated scientific language.  The answer is simple.

It does not matter.

The answer does not matter because the simple fact is that we are not getting through to a large amount of people. That there will be a contingent who do not listen. We pushed hard for vaccinations and mask wearing during Covid but how many other issues are there which are just as complicated and have been oversimplified, such as renewable energy good non-renewable energy bad, or have not been simplified enough to be understood. How many issues do we have which we have the solutions for? Problems with answers which we just say, “people won’t listen we do not have a way to get them to listen” and now we can stand on the side-lines and continue to complain and shake our fists as the world constitutes to worsen.

I am a deeply practical person and because of that I will use a practical example here.

Imagine your individual with a group of friends are going camping. You have a manual for how to set up a tent you all must sleep in. You have read it and you know exactly how to set it up.

However, it is the large tent, and you cannot put it up by yourself. Each year you go, each year you ask people to read the manual but it’s too complicated and they don’t have time.

Each year you continue to complain that nobody is reading your manual. That’s excellent, you’re right. But when you go to bed at night when you are camping the fact that you were right doesn’t stop the water from spilling in on top of you. It doesn’t stop your clothes from being soaked, your camping ruined.

So, when you continue, each year, sitting there, being correct, with the same unfortunate result. Are you going to just keep being right? Or would you attempt to teach your friends have put up the tent, try make a manual with diagrams which are easier to understand. You might do something else entirely. But you certainly wouldn’t go back each year using the same strategy knowing that it doesn’t work.

We as scientists, as a community, as a people, we want to solve problems, we want, to discover things.

However, it is clear that we won’t make the necessary change we need to change the world for the better unless have everybody else come in and contribute. We need everyone else to work with us to make a difference.

Say, for example, the entire scientific community comes together and makes a master document which solves of all problems in the world in 50-years. It’s complicated but it will work. This miracle solution does not matter if we cannot get others to read and implement it. Or if we do not accommodate for those who will not read it. If we cannot get them to, we must at least find a way for them to do their part, by understanding the benefits of this miracle plan and the benefits of the parts that they are contributing to said plan.

What is the solution to this? I wish I knew. As if I knew I could put in an overly complicated document that nobody would read.

Now I am being a bit coarse. This is a deeply complicated matter as all matters of people are. Especially people on a large scale and a perfect solution is not known. At the very least not known by me. However, there are several things which can be done. If politics is what changes the world, perhaps more scientists should go into politics. Or at the very least be someone who would inform and attempt to educate not only politicians but the masses and the people around them.

Try to teach them try to help instead of simply assuming that everybody has had the privilege of the long-standing education and the choice of education which we as a community have chosen.

Will it be difficult? For sure. Will it be slow? Absolutely. Will it be worth it? There is no doubt, if we truly want to begin changing the world.

I believe the great minds of the scientific community may well be able to figure out how to change the world. But that means nothing if we do not first strive to add the rest of the world into our community. To educate and help them so they know what is going on, what we are striving for. To have an idea of what must be done so they may help us, and we may all help each other towards the better tomorrow, and a better world.

 

REFERENCES

[1]Our World in Data. 2022. Electricity production by source. [online] Available at: <https://ourworldindata.org/grapher/electricity-production-by-source?country=~FRA> [Accessed 12 May 2022].

[2]

Our World in Data. 2022. Electricity production by source. [online] Available at: <https://ourworldindata.org/grapher/electricity-production-by-source?country=~IRL> [Accessed 12 May 2022].

It is no secret that Europe is trying to wean itself off Russian gas after the invasion of Ukraine. European citizens find themselves in the repulsive position of propping up the Russian regime through the purchasing of Russian gas to power our electrical grids. There is also a massive effort within the EU to divest from carbon producing means of energy production. The task of divesting from fossil fuels and untangling European economies from Russian gas is immense but what if Europe could pool its energy resources together to create one, large, pan-European grid? If this could happen wind farms off the west coast of Ireland could power factories in Germany or solar panels in Portugal could power homes in Italy. This way, when the wind doesn’t blow or the sun doesn’t shine in one region of the continent, energy can be produced in and distributed from another. The problem with this idea is that it costs to transport electricity.  This cost is attributed to transmission losses due to heat as well as financial costs due to large transmission and collector stations needed to transmit power. This is where superconductivity comes in.

 

Superconductivity is a phenomenon in physics where certain materials display zero electrical resistance when cooled to temperatures of around 80 Kelvin (-1930C).  Superconductivity is a quantum effect best described by Cooper pairs. In a normal conductor, electrons flow freely throughout the lattice of atoms and are repelled by one another. Events such as scattering, the collision of an electron with an atom, diminish the flow of electrons and cause resistance. However, in a Cooper Pair, electrons are slightly attracted to each other. This attraction is due to electrons interacting with phonons which are waves of vibration in the lattice. When these electrons are paired up, they have a lower energy. This creates an energy gap between the energy of the electrons and the energy needed for events such as scattering, meaning scattering will not occur and resistance falls to zero. Superconductivity only works at low temperatures as the Cooper bond in an electron pair is very weak and thermal energy, the energy due to temperature, can break the bond in these Cooper pairs. The temperature below which a material exhibits superconductivity is called the critical temperature.

So, superconductivity allows the flow of electricity with zero resistance, and therefore zero power loss, if the conductor is below a certain temperature. An important temperature in superconductivity physics is 77K, the temperature Nitrogen boils at. This is because if a superconductor with a critical temperature above 77K is used, liquid Nitrogen can be used to cool it. Liquid Nitrogen is readily available and relatively easy to produce, making it the perfect cooling agent.

Superconductivity is going to play a massive part in the future of energy transportation in Europe and indeed in the world. It is an area where physicists can contribute to one of the biggest questions facing our generation with regards to energy security. “How do we keep the lights on?”

Any form of technology with the purpose of being consumed by the public is consumer technology. This includes computers, phones, cars and anything else like that. Each year we see new innovations to these products that make them become better and better each year. Take self driving cars for example, back fifteen maybe twenty years ago most cars still had old crank style windows which you had to manually crank to open the window, a few years later Tesla announces that they are working on self driving cars. Surly at this rate we would have some crazy technology that we could not even imagine having 10 years ago right? Well yes and no. 

Developments in physical hardware have come a long way in the past 20 or so years. Phones in the early 2000s were just a tiny screen with some buttons on it used to call your friends. Now it’s advanced so greatly to where phone companies are trying to make the screen so big that they want them to fold in half just so it will fit in your pocket. Samsung has been leading the way right not with their foldable phones, but how does it work? OLED screens are made up of an organic material that will emit light when electricity is passed through them. This means that they do not need a backlight to physically light up the screen therefore they can be made extremely thin. Samsung has now developed these OLED screens from a flexible anode layer and a flexible polymer layer to put on top which results in a fully flexible and folding screen. They have now gone one step further and made extremely thin glass that can be flexible and does not break when folded. Clearly these are huge steps in physical hardware technology and there are so many other examples that can be used like new chips used in computers or phones to make them have more processing power, but I do think we are hitting a limit where the laws of diminishing returns are starting to come into play. The more we pay for a specific product we will reach a certain point where we don’t get equal value for our money. We can buy a cheap computer for 500 euro and it runs ok, but if we spend 2000 we get something even better, but if we spend upwards of 4000 we don’t get the same amount of gain we get from going to 500-2000 to 2000-4000. We are getting to the point where we have all these theories and knowledge on how to make physical hardware for technology better but it’s just not practical. Making these latest and greatest products it’s not cheap so it’s not going to be cheap to buy. That Samsung fold phone for example was around 2000 euro when it was first released. Even a regular new iphone goes for around 1100 euro which is insane to think about even a new computer just to do college work on will set you back that much and maybe more. Physical technology will always continue to grow and evolve even with minor incremental gains, but do I think we will see the same gains we have seen from early 2000s till now, from now till 2040s? I really hope so but it’s hard to say

One thing that has huge potential though is software technology. Today we are seeing great advancements in the field of artificial intelligence (AI). I remember a few years ago Google announced that they have made some strides in AI and were claiming to do some quite unique things. They have created an AI that is able to take and make calls for you like booking a table at a restaurant for something along the lines. This was announced back in 2018 and now in 2022 it must have come a lot further. There are so many examples of consumer technology with AI built in that people actually want to buy, this could be like mentioned above a tesla self driving car or even something more simple like a Samsung fridge where the AI takes stock take of items in the fridge and will let you know if you are out of an item or if something is close to out of date. We are getting to a point where lots of just everyday items will include some sort of AI just to help us with day to day tasks which is great. I certainly do not see us peaking on a software technology front for many years as machine learning and AI is a very difficult task to accomplish anyway, but to push us into this automated future where a computer is doing simple tasks for us people will keep working on this to make it better and better and to make it more readily available to the average person.

 

 

 

 

 

by Romain Bievelez

Image from www.brannlaw.com

A human crowd is very complex and fascinating. It can shape the world during elections (for the best or the worst). It can save lives and it can kill. Information and diseases can propagate through it and it behaves very specifically during waves of panic. Scientist have been now studying human crowds for decades. It may surprise you but it turns out that physicists are the foremost type of scientists that study human crowds, more than psychologists and biologists!

In this blog, you will learn about all sort of characteristics and behaviours of crowds. You will understand why crowds are studied mostly by physicists and you will learn about the impact that crowd behaviour can have.

But first, before jumping into this amazing topic, let us first define what is actually meant by “crowd”. It doesn’t have to be physical or tangible. A group of people chatting on social networks is here considered to be “a crowd”.
A human crowd is a group of people that are somehow interacting with each other.

Now that we know what a crowd is, we can dive into learning how it behaves in some classic situations.

Physicists started by studying movements in crowded areas. It has been seen very quickly that crowds move like fluids or granular solids (like sand or gravel). They literally “flow”. It comes from the fact that, in some sense, humans repel each other in the street. Obviously, when you are walking on the pathway, you don’t want to bump into the person that is coming in front of you. So, when the collision seems imminent enough, you deviate from your path to the easiest alternative way. This very simple behaviour (which is shared by a huge amount of social animal species) leads the crowd to flow like a fluid.

Image of a crowd behaving like a fluid from www.gae-engineering.com

This “fluid physics” description can be very accurate and lead to useful conclusions. For example, did you know that, in a crowd during a panic wave, you must avoid at all cost the edges of the crowd? You must follow the flow and stay in the middle of “the wave” to avoid getting injured!
Why is that? It is because the pressure gets bigger on the edges of a fluid. In other words, the shocks become more frequent and violent near the walls of the container. These could be the walls of the room and the buildings in the street.

Here is another fact: did you know that putting an obstacle in front of an emergency exit actually speeds up the evacuation? Yes! It is counter-intuitive. But like sand flowing through a hole. If you put a thin object in front of the door, it actually “breaks the flow” and help avoid congestion at the door.

Another similarity between fluids and crowds is that some things can propagate and diffuse through them. For example, fake news and diseases can propagate through a human crowd and it is a certainty that describing and understanding their spreading will help predicting and preventing popular misconceptions and pandemics.

But how can we do that? How can one predict how a disease will spread into the population? Actually, we haven’t reached this capacity yet. But we know how to reach it. We need to “model” disease spreading as accurately as possible. Modelling means basically to describe something using math. Let’s say you want to model the quantity of virus among the population. What you want is actually a function of time giving the quantity of virus. In other words, you want a mathematical rule that gives the quantity of virus if you give it a date.

Image of a crowd simulation software from www.lsi.upc.edu

Nowadays, scientists can predict much more than just the number of virus. To do so, they use advanced mathematical tools such as the so-called “discrete diffusion equation in finite space”. This long name refers to a mathematical rule that describes how anything can propagate (or diffuse) into a space that as boundaries (like a room for example). With such tool, we are now capable of accurately predicting how a virus would spread among a small group in a room!

Crowd study is what we call an “empirical” science. It means that experiments play a central role in the development of this science. But what does it mean to “measure a crowd”? The most common ways of measuring a crowd are, first, simply giving a survey to all the participants of the experiment and, second, recording the crowd on camera and then analysing the recordings. Most of the time, physicists use this second option. It is perfectly suited for the study of movements as we have now advanced software that can track people on an image. It than also allows to measure the so-called “crowd density”: the number of people per square meter which is so important to assess injury risks in a crowd.

But then, how can we measure large population movements like migrations for instance? Physicists have now discovered that seismology could be used as a non-intrusive tool for population tracking.
Basically, we can now identify the human influence in seismic noises recorded on ground vibration captors all around the world. This will be used to record population migration over thousands of kilometres without actually breaking into people’s private life.

Crowds can actually become useful. For example, it has been discovered that a crowd of doctors is very effective at avoiding antibiotic over-prescription.
Studying crowds has also applications in other sciences that are related to population study. A lot of tools developed for human crowd studying are used now to study other animals. We can now track the movements of flocks of bird, herds of sheep and shoals of fish. We can dynamically control flocks of drones and take effective measures against the spreading of diseases.

It makes no doubt that crowd study is a fascinating science with loads of applications and utilities and it has a great future with plenty of discoveries.

 

References:

“The physics of fluids explains how crowds of marathon runners move” by Emily Conover, ScienceNews:

https://www.sciencenews.org/article/physics-fluids-explains-how-crowds-marathon-runners-move

“Math to match pedestrian behavior is all about timing” by Andrew Grant, ScienceNews:

https://www.sciencenews.org/article/math-match-pedestrian-behavior-all-about-timing

“Solution to century-old math problem could predict transmission of infectious diseases”, ScienceDaily:

https://www.sciencedaily.com/releases/2020/05/200529150617.htm

“Harnessing the ‘wisdom of crowds’ can help combat antibiotic over-prescription”, ScienceDaily:

https://www.sciencedaily.com/releases/2020/11/201103115656.htm