Simon’s visualization of the notorious thee-body problem (two stars and a particle) in 1D: https://editor.p5js.org/simontiger/sketches/WTUoBaxgo and in 2D: https://editor.p5js.org/simontiger/sketches/B0pQl94pd

# Tag Archives: Physics

# World Science Scholars Feature Simon’s visit to CERN in a newsletter. The current course is about neurons. Reading Stephen Wolfram.

Simon’s September visit to CERN has been featured in a World Science Scholars newsletter:

Here’s our update on the World Science Scholars program. Simon has finished the first bootcamp course on the theory and quantum mechanics by one of program’s founders, string theorist Professor Brian Greene and has taken part in three live sessions: with Professor Brian Greene, Professor Justin Khoury (dark matter research, alternatives to the inflationary paradigm, such as the Ekpyrotic Universe), and Professor Barry Barish (one of the leading experts in gravitational waves and particle detectors; won the Nobel Prize in Physics along with Rainer Weiss and Kip Thorne “for decisive contributions to the LIGO detector and the observation of gravitational waves”).

At the moment, there isn’t much going on. Simon is following the second course offered by the program, at his own pace. It’s a course about neurology and neurological statistics by Professor Suzana Herculano-Houzel and is called “Big Brains, Small Brains: The Conundrum of Comparing Brains and Intelligence”. The course is compiled from Professor Herculano-Houzel’s presentations made at the World Science Festival so it doesn’t seem to have been recorded specifically for the scholars, like Professor Brian Greene’s course was.

Professor Herculano-Houzel has made “brain soup” (also called “isotropic fractionator”) out of dozens of animal species and has counted exactly how many neurons different brains are made of. Contrary to what Simon saw in Professor Greene’s course (mainly already familiar stuff as both relativity theory and quantum mechanics have been within his area of interest for quite some time), most of the material in this second course is very new to him. And possibly also less exciting. Although what helps is the mathematical way in which the data is presented. After all, the World Science Scholars program is about interdisciplinary themes that are intertwined with mathematical thinking.

Another mathematical example: in Professor Herculano-Houzel’s course on brains we have witnessed nested patterns, as if they escaped from Stephen Wolfram’s book we’re reading now.

Simon has also contributed to the discussion pages, trying out an experiment where paper surface represented cerebral cortex:

Simon: “Humans are not outliers because they’re outliers, they are outliers because there’s a hidden variable”.

Simon is looking forward to Stephen Wolfram’s course (that he is recording for world science scholars) and, of course, to the live sessions with him. The information that Stephen Wolfram will be the next lecturer has stimulated Simon to dive deep into his writings (we are already nearly 400 pages through his “bible” *A New Kind of Science*) and sparked a renewed and more profound understanding of cellular automata and Turing machines and of ways to connect those to our observations in nature. I’m pretty sure this is just the beginning.

It’s amazing to observe how quickly Simon grasps the concepts described in *A New Kind of Science*; on several occasions he has tried to recreate the examples he read about the night before.

# Some Physics Demos with Geomag

# Diffusion Experiments

# CERN Open Days September 14 – 15, 2019

The most important experience was actually simply to see how huge the Large Hadron Collider is. We totally didn’t expect the site of every experiment on the 27km ring to resemble an industrial town in its own right, scattered miles across a desert-like terrain with the Mont Blanc and the Jura mountains as the scenic back drop. It was a challenge to walk between the activities we had carefully planned in advance only to find out that some of the were full or required an hour of waiting in line. But the kids have withstood these challenges heroically and were rewarded with a few unforgettable impressions.

# Surrounded by the equations that changed the world

At the main entrance to CERN there is an impressive smooth curve of a memorial to the world’s most important equations and scientific discoveries:

# Simon’s experiment about gradients

How he designed and made it:

# Supersymmetry: Why do we need the Future Circular Collider?

This is the text of the mini-lecture on Supersymmetry that CERN Research Physicist, CMS supersymmetry group convener and Deputy LHC Programme Coordinator Filip Moortgat kindly gave us during our visit to CERN and the Large Hadron Collider last week.

Filip Moortgat: Supersymmetry stands out among all the other Beyond Standard Model theories (like extra dimensions and so on). It’s particularly interesting because it answers multiple things at the same time. I would say that most other extensions of the Standard Model solve one problem but not five like supersymmetry.

The first problem: because it connects the internal property of a particle to spacetime, it actually opens a way of gravity entering the Standard Model. As you know, the main problem with the Standard Model is that gravity is not in there. So one of the major forces that we know exists is not in there. Nobody has succeeded to make gravity part of it in a way that is consistent. People hope that supersymmetry can do it, although we’re not there yet.

The second problem is called the hierarchy problem. What that means is that you have a base mass for a particle and then you have corrections to it from all the other particles. What happens is that if you don’t have any other particles beyond the Standard Model particles you get corrections that become gigantic. What you need to do is tune the base mass and these corrections so that you get the mass that we measured for the Higgs Boson or for the w and z bosons. It’s like 10^31 minus 10^31 is a 100 type of tuning, and we find it unnatural. It’s ugly mathematics. In supersymmetry, you get automatic cancelation of these big corrections: You get a big one and then you get minus the big one (the same correction but with a minus in front of it), it cancels out and it’s pretty, it’s beautiful.

The third thing is dark matter, a big problem. 85 procent of the matter in the universe is dark matter (if you also include the energy in the universe, you get different numbers). And the lightest stable supersymmetry particle is actually a perfect candidate for dark matter, in the sense that it has all the properties and if you compute how much you expect it’s exactly what you observe in the universe. It works great. It doesn’t mean that it’s true, it would work great if you could find it.

And then there’re more technical arguments that make things connect together in nicer ways than before. Normally, the electric symmetry is broken in the way that everything becomes zero. All the masses would be zero, the universe would just be floating particles that wouldn’t connect to each other, it would be very boring. But that’s not what happened. To show what actually happened you need to drive one mass squared term negative, which is kind of weird but that is what supersymmetry does automatically! Because the top quark mass is so heavy. Heavier than all the other quarks. For me it’s the most beautiful extension of the Standard Model that gives you a lot of solutions to problems in one go.

The problem is that we haven’t seen anything, yet! We have been looking for it for a long time and we have absolutely zero evidence. We now have reasons to believe that it’s not as light as we have originally thought, that it’s a little bit heavier. Which is not a problem. The LHC has a certain mass range, for supersymmetry it’s typically up to a couple of TeV. But it could be 10 TeV and then we couldn’t get there, we can only get up to 2 or 3 TeV. It could be factor 10 heavier than we think!

This why we are starting to discuss the planning of the Future Collider that will be able to go up the spectre of 10 TeV in mass, for supersymmetry and other theories. There’re several proposals, some of them are linear colliders, but my favourite one is a 100 km circular collider which will connect to the LHC, so that we have one more ring. That ring will actually go under the lake and that would be quite challenging, but in my opinion – although we don’t have any guarantee – we will then have a very good shot, at least in terms of supersymmetry. At the LHC we also have a good shot but don’t have enough reach that we need to really explore the supersymmetry.

When we use conservation of energy and momentum at the collision point, what we do is we measure everybody, we sum it all up and what we need is we need to get the initial state. If something is lacking, then we know there’s something invisible going on. It could be neutrinos, or neutralinos, or it could be something else. So we have to look at the properties and the distributions to figure out exactly what we’re seeing. It’s not a direct detection but it’s a direct derivation if you want, from not seeing something, from lacking something, that we can still say it is consistent with neutralinos.

How do you know if it’s neutrinos or neutralinos?

Neutrinos we know well by now so we know what to expect with neutrinos. Otherwise it could be neutralios but it could be something else. And then to actually prove that it’s neutralinos we have a long program of work.

And is that mainly math?

No, it’s everything. It needs all the communities to work together, because we need to measure certain properties, distributions with the detector and we will need the theoretical ideas on how to connect these measurements to the properties of the particle. So we will need both the mathematical part and the experimental part. Translating the mathematics into the particle predictions, we will need all of that.

# The Camera Obscura at the Royal Observatory in Greenwich

# Simon introducing himself for the World Science Scholars program

This is Simon’s introductory video for the World Science Scholars program (initiative of The World Science Festival). In May this year, Simon has been chosen as one of the 30 young students worldwide, joining the 2019 cohort for exceptional talents in mathematics. Most of the other students are 14 to 17 years old, age was not a factor in the selection process. To help the students and their future mentors to get to know one another, every World Science Scholar was asked to record an introductory video, no longer than 3 minutes, answering a few questions such as what is the biggest misconception about math, what your favourite branches of math and science are and who among the living mathematicians you’d like to meet.

Throughout the program, the students are given access to over a dozen unique interdisciplinary online courses and have the option to complete an applied math project, alone or as a team, consulting real experts in the field of their project. Simon has already started the first course module, on Special Relativity by Professor Brian Greene. The course has been specifically recorded for the World Science Scholars and reflects the program’s ethos: it’s self-paced, no grades, it relies on beautiful animations and visualizations, it’s full of subtle humour, is dynamic, thought-provoking and quite advanced (exactly in The Goldilocks Zone for Simon, as far as I could judge), yet broken up into easy-to-digest pieces. It’s difficult to predict how Simon’s path as a World Science Scholar will unfold (I’m afraid of making any predictions as he is extremely autodidact), but so far we have been very pleased with the nature of this program and it seems to match our non-coercive, self-directed learning style. I have especially liked one of the course’s main postulates: “Simultaneity is in the eye of the beholder”.