orbifold

Yeah no this is not happening, the young people will revolt before that. You can suspend civil liberties for a few months, that's fine, but not intermittently over several years. No way that governments in western countries will get away with that. I expect this to be an event that will remove most baby-boomers from power and bring in the millennial generation, they expect us to support ~5 old people through most of our productive life and now they created or are about to create debt that we will have to pay off for the rest of our lives. A lot of it is to prop up pension schemes and assets which are primarily owned by old people and projected to have collapsed by the time a 30 year old will retire.

There is a pretty nice parser combinator library in the capnproto compiler: https://github.com/capnproto/capnproto/tree/master/c%2B%2B/s.... Here is an example of how it is used: https://github.com/capnproto/capnproto/blob/950d23a13f1d602d...

In the case of differential calculus Leibniz (a German) came up with it at roughly the same time and his notation and approach is what actually stuck. In the case of Maxwell's equations it was Heaviside who came up with the vector formulation as four equations and it took Grassman, Cartan and Hodge to arrive at the modern two equation formulation in terms of differential forms.

Anyone that ever had close contact to what the UN does, knows that it is a corrupt, inefficient and grossly incompetent organisation, filled with cousins of African strongmen and other connected people. Same goes for people working in NGOs cooperating with the UN, a common arrangement for example in Geneva is that while the partner works as an oil broker, the other writes position papers on women's rights and observes meetings that has half of the members of the subcommittee asleep.

Well they believed they would see supersymmetric particles at older colliders as well. The problem now is that the Higgs mass anchors the valid range for "natural" supersymmetric models. Last I checked most of those where ruled out now. That still leaves the problem that the Higgs mass is unexplained. So the obvious step is to do Higgs precision measurements, which is what they intend to do with electron-positron colliders tuned to the Higgs mass.

I actually think it is the same in chemistry, knowledge of which approaches don't work are a competitive advantage that is passed around under the hand. I've definitely observed this is in theoretical physics and pure mathematics, it is often much more important to know about things that have never been published then it is to read close to incomprehensible publications. So for example it is much more valuable to have attended the right seminars and have private copies of lecture notes, because by the time something is published it probably is out of date 1-3 years.

The interest over time graph uses spline interpolation to connect the datapoints, while that might look prettier than straight lines, it is something that is strongly discouraged in a scientific / data analysis context, because the curving line does not carry meaningful information.

I've seen M4 used to implement instruction decoding logic (for the POWER instruction set) in a design and to describe a bus interconnect in system verilog. Still not sure if it was a good or bad idea...

Something related is happening with commercial real estate in Germany: Big retail chains like H&M, adidas, Deichmann have stated they won't be paying rent beginning in April (they were forced to close their stores). Ironically democratic socialists have complained about that. My guess is that this will be a rude awakening for the rent seeking individuals that profited from record low credit to finance and then rent out properties at record rental rates.

There are a few themes that physics revolves around:

1. Action Principle: A lot of problems in mechanics can be boiled down to writing down the correct Lagrangian.

2. Statistical physics, this teaches you about to think in terms of "Zustandssummen" and is the starting point for deriving lots of interesting laws like black body radiation.

3. Field (Gauge) Theory, turns out you can write down and derive interesting Lagrangians for Electrodynamics, Fluid Dynamics and General Relativity as well.

3.1. Noethers Theorem and Symmetries allow you to get a unified view of conserved quantities.

4. Spinors, they are fundamental for understanding the quantum behaviour of matter

5. Path Integrals necessary to understand Feynman diagrams and Calculations in Quantum Field Theory.

6. Do the harmonic oscillator in as many different ways as possible, a lot of physics can be understood by solving the harmonic oscillator or coupled oscillators. Once you've understood why this is the case and the situations in which it isn't true, you will have understood a lot of physics.

I would recommend a depth first instead of breadth first approach. Pick something advanced that really interests you and work backwards what prerequisites you need to understand it. There are parts of classical physics that are super interesting but barely anyone learns about them anymore (I skimmed through Sommerfeld's lectures on theoretical physics once, they contain all kinds of super interesting problems with spinning billiard balls, tops and so on, this was at a time when Quantum Mechanics was in its infancy).

None of those can beat it in symbolic computation. You can write entire papers, by simply asking yourself the question: I wonder if this has an analytical integral? If you are lucky Mathematica spits out a solution in terms of a special function.

Just to clarify because it is not obvious from the homepage: This is not actually organized by the government, but by a private non-profit startup funded by the federal government. That makes some difference and now I've given my email address to a random Berlin startup.

I have puts on a bunch of stocks that target the 52 week low or 10-15% below that in ~3 months. So far that strategy has been wildly profitable. There have been tons of stocks that doubled or tripled in value in 2019, no way that is a realistic price in the next 2-3 years.

All these people working on the foundations of quantum mechanics must somehow have missed the fact that quantum mechanics has been superseded by quantum field theory. Quantum field theory resolves basically all of the typically interpretation of quantum mechanics questions in a rather sophisticated way. Unfortunately and I guess this is why these "Interpretation of QM" are still popular most things become harder to calculate with QFT instead of plain old quantum mechanics. Still I think that the perspective of taking quantum fields and the path integral as fundamental clarifies a bunch of things even about measurements. In the path integral formulation you can view a measurement as an additional term in the Lagrangian (for example a non-zero external magnetic field for Zeeman-Splitting). You then have to expand around the classical solutions summed over all initial conditions, so if you have for example a spin-1/2-based dependence as it is the case for the Zeeman-Effect, you would have to expand around these two different classical solutions. There is nothing mysterious about this and in the cases where you can carry the calculation out you get the correct predictions. Fundamentally there is no such thing as measurements, just local interactions of quantum fields and any measurement can be either modelled as such an interaction or as an additional term in the Lagrangian.

The truly interesting things discoveries within in the framework of quantum field theory, such as ADS/CFT, going from String Theory to low energy effective theories or the Amplituhedron. All of those have direct and immediate connections to state of the art quantum field theories.

What is done in (https://arxiv.org/pdf/1912.06462.pdf), especially the last part, where they suddenly invoke p-adic numbers in support of a very vague argument and a cartoon of Penrose's impossible triangle in a similar vague manner, won't be taken serious by most physicists, but is sufficient apparently to convince non-technical people to continue funding them. Nautil.us probably is just grateful for the free content.

The classical use case is EDA software, which still largely runs on Linux. I can run simvision (a cadence tool) on a large server with ~96 cores and ~1TB of ram and the spawned windows integrate (almost) seamlessly with my multi monitor MacBook Pro setup. That Software only supports Solaris (recent releases dropped that I believe), specific versions of Red Hat Linux and Windows. Large simulations easily consume all server resources and require a SSD raid to function effectively. This also isn’t software you want to have to install or maintain yourself, plus it need access to proprietary information protected by NDA, which is not allowed to be copied to private hardware.

I would say that while the above numbers are certainly the current academic consensus, what also is part of the consensus is that this missing matter is interacting weakly and at very high energies. So for all intends and purposes it is mostly irrelevant baring some unforeseen breakthrough that lets us interact with it more strongly (for the same reason everything but the electric force is kind of irrelevant from an engineering perspective).

In my estimation it is precisely the other way around. There are hardly any applications of blockchains that are not equally well solved by other methods, whereas computer vision alone has a huge number of applications and “neural network” based solutions are now undoubtedly the best approach to a huge number of hard computer vision problems.

In my estimation it is precisely the other way around. There are hardly any applications of blockchains that are not equally well solved by other methods, whereas computer vision alone has a huge number of applications.

The smartest people I know are mathematicians or physicists most of them couldn’t care less about any of the historical narratives you‘ve just mentioned.

Grothendieck left IHES in 1970, the second edition was after that. There was a lot of drama in the aftermath, essentially Grothendieck was not happy about how the more advanced material (SGA 4) he lectured on was kept private to the small group of students that attended the seminar and later reappeared in their publications without much acknowledgement. The eventual SGA 4.5 was a butchered version that only contained enough background to cover Deligne‘s proof.

It really is insane, I know people who don't even work for SAP, are "IT consultants", whose credentials are a (very good) Art History degree and travel around nationally and internationally to essentially push a button to do SAP database migrations after mergers and acquisitions. There are independent companies that just live off the fact how bad SAP is.

The CPUs that handle 86% of all credit card transactions for example (in the various mainframes IBM builds). Pretty nice modern architecture still capable of executing 60 year old code.

Well the book certainly makes it look much more mundane, Simons appears to be more of a skilled people manager and the heavy lifting was apparently done by others for the most part.

This is compatible in so far as you need to estimate parameters to calibrate any such strategy. In the simplified model that is explained in the lecture notes I linked to, you would start with eq. 6.6 on page 25 as an Ansatz for the transition matrix in the Baum-Welch algorithm.

The assertions you make are not necessarily in contradiction to what I am saying. In discretised form most of the formulas I'm talking about boil down to simple linear algebra with unknown parameters. You can then use essentially linear regression to find those parameters, based on observed market data and trades you are making.

So I was talking about the "what should I be regressing" and "transformation" (you can use gauge theory to adjust for inflation and changes in exchange rate in non-obvious ways) part. There is no question that having access to enough data and operational excellent are a complementary component.

My long standing hypothesis on Medallion is that they figured out how to apply gauge theoretic techniques to financial markets. This fits with Simons work that he did before he founded the fund. The fact that gauge theory is applicable to for example currency trading is folk knowledge in the Havard, Princeton, IAS circles (here is for example the lecture notes of a popular lecture by Maldacena that uses currency trading as an example of a gauge theory https://arxiv.org/pdf/1410.6753.pdf).

In currency trading example the curvature $F$ of the gauge connection $A$ vanishes precisely, when there is no arbitrage opportunity. Now what Chern and Simons discovered is a differential form K (https://en.wikipedia.org/wiki/Chern–Simons_form), which when taken as the action S(A) of a gauge field $A$, has a corresponding field equation $F = 0$ (i.e. in the finance case = no arbitrage). In these equations time does not enter, however there are several ways in which on can incorporate time into the picture (for a naive example see also the lecture notes). Assets in this framework live in associated vector bundles of the principal bundle defining exchange rates.

My speculative assertion is that it is possible to identify "topological invariants" which can be computed by sequences of trades, i.e. parallel transport along the gauge connection and that those can have provably positive expected return. The fact that the fund is limited to a small amount of invested capital might be related to the fact that the strategies require measurements, that would have self-interactions if they were too large.

All the big German automakers are, as is Bosch.

As a slight counterpoint (I haven't looked into the claims of the patents too much): There is the well known Kerr-Newman solution of a rotating, charged black hole. It is well known that a relativistic rotating charged disk approximates in the limit of (v = c) the Kerr-Newman solution with (B = 0): https://arxiv.org/pdf/gr-qc/0410109.pdf. However the total field energy of such a rotating disk would be infinite, this is one of these examples in physics, where you run into pathologies. As is remarked in the paper those might be removed by a quantum treatment. For v < c the field energy is finite, which is in any case the only realisable regime.

Which is probably one of the reasons why Julia takes ages to do a simple plot.

I don't know how that relates to EU projects. I'm not alleging corruption, just stating facts. The flagship projects were promised 1 billion in funding over 10 years. A lot of that money was spend in Switzerland, which isn't even a EU member state. The last funding period will now actually involve 20% in administrative overhead, spend on administrators mostly located in Switzerland. I've seen some of the planning diagrams for future European cloud initiatives especially in the HPC sector. Most of it is just shuffling around funds from one budget to another, that is they relabel existing HPC infrastructure and university compute resources to be now part of a "European Research Cloud" (https://ec.europa.eu/research/openscience/index.cfm?pg=open-...)

Another aspect is that as soon as a university is involved, you get lots of cheap basically black labor by gullible university students. Take https://qt.eu for example, they promise 1 billion in funding over 10 years and 5000+ researchers. That works out to 20000€ per researcher per year. A PhD student in Germany makes roughly double that, if he has a fully funded position. So this figure relies on:

- Paying people half the normal salary, but expecting them to work full time, which is common practice in European academia.

- Significant additional funds being provided by member states and universities, all the while the European Union has the leverage to call the shots on research direction and funding.