## Topological Quantum Computing Articles

May 5, 2019

Through browsing a recent edition of Nature, I recently came across the following articles on topological quantum computing, or which at least touched on aspects of condensed matter physics relevant to said research direction.

These are the papers:

and one bonus article from more recently:

The bottom line of this work is that it appears to me that researchers at Microsoft, and various other institutions, are closing in on building a working topological qubit that would lend itself to scaling up to a practical quantum computer.

What is a topological quantum computer? A good question. This jargon essentially means, ‘use a Majorana fermion (a particle that is its own antiparticle) to do something weird with anyons in order to achieve highly stable qubits through topological properties that are hard to deform, then couple these together to make a computer’.

More on majorana fermions can be found here: https://arxiv.org/abs/1712.06156 . The topological ‘hardness’ of these exotic things that arise within certain condensed matter systems essentially rests on something-something braid groups, per a talk I remember Michael Freedman giving at a conference I attended in New Zealand about 13 years ago (January 2006) in Taipa, New Zealand. That was actually a very interesting conference, with a number of luminaries, including John Conway who spoke about his Game of Life. Anyway, enough name dropping; my point was that Michael Freedman spoke briefly about braid groups there as part of his work for a thinktank at Microsoft, “Microsoft Station Q”.

Another good introduction to topological quantum computing can be found here: https://arxiv.org/abs/1802.06176 .

What is a non-Abelian anyon? First of all, an abelian anyon is a quasiparticle that obeys statistics between Fermi-Dirac and Bose-Einstein. State is preserved with Abelian Anyons.

A non-abelian Anyon is a type quasiparticle that does not necessarily preserve state. In the landmark 1988 paper by Jürg Fröhlich, “Statistics of fields, the Yang-Baxter equation, and the theory of knots and links.” Nonperturbative quantum field theory. Springer US, 1988. 71-100., Fröhlich described the properties of such potential quasiparticles (paywall).

In https://arxiv.org/abs/1802.06176 which is in fact a rather excellent introduction to this subject, the usage of non-abelian Anyons in this mix is made clearer. Indeed, on page 3:

There are three fundamental steps in performing a topological quantum computation, illustrated in Fig. 1.

1. Creating qubits from non-Abelian anyons.

2. Moving the anyons around—‘braiding’ them—to perform a computation.

3. Measuring the state of the anyons by fusion

https://arxiv.org/abs/1802.06176

Physical realisation of this system is where things are currently in a state of flux. Indeed, certain types of non-Abelian anyons can be also what are known as Majorana fermions.

A Majorana fermion is a neutral spin-​12 particle that can be described by a real wave equation (the Majorana equation (1937)). A property of solutions to this wave equation is that they happen to be their own antiparticle.

As to the papers above, it will take some digging to really get to the heart of where things are in this field at the moment, but it looks totally fascinating.

In https://arxiv.org/abs/1712.06156 , the researchers claim that they were able to produce chiral majorana fermions, a type of non-abelian Anyon, in a “hybrid device of [a] quantum anomalous Hall insulator and a conventional superconductor“.

In https://arxiv.org/abs/1809.03076, the researchers were able to exhibit “Topological superconductivity in a phase-controlled Josephson junction” (paper title). From the abstract:

Topological superconductors can support localized Majorana states at their boundaries. These quasi-particle excitations obey non-Abelian statistics that can be used to encode and manipulate quantum information in a topologically protected manner.

https://arxiv.org/abs/1809.03076

So they essentially claim that they were able to implement one of the building blocks of the proposed system in https://arxiv.org/abs/1802.06176 through control of a type of Josephson junction. Interesting. They go on:

While signatures of Majorana bound states have been observed in one-dimensional systems, there is an ongoing effort to find alternative platforms that do not require fine-tuning of parameters and can be easily scalable to large numbers of states. Here we present a novel experimental approach towards a two-dimensional architecture. Using a Josephson junction made of HgTe quantum well coupled to thin-film aluminum, we are able to tune between a trivial and a topological super-conducting state by controlling the phase difference φ across the junction and applying an in-plane magnetic field.

https://arxiv.org/abs/1809.03076

In https://arxiv.org/abs/1809.03037, the researchers seem to have built on the previous result and were able to exhibit “Evidence of topological superconductivity in planar Josephson junctions”. From the abstract (my emphasis):

Majorana zero modes are quasiparticle states localized at the boundaries of topological superconductors that are expected to be ideal building blocks for fault-tolerant quantum computing. Several observations of zero-bias conductance peaks measured in tunneling spectroscopy above a critical magnetic field have been reported as experimental indications of Majorana zero modes in superconductor/semiconductor nanowires. On the other hand, two dimensional systems offer the alternative approach to confine Majorana channels within planar Josephson junctions, in which the phase difference {\phi} between the superconducting leads represents an additional tuning knob predicted to drive the system into the topological phase at lower magnetic fields. Here, we report the observation of phase-dependent zero-bias conductance peaks measured by tunneling spectroscopy at the end of Josephson junctions realized on a InAs/Al heterostructure. Biasing the junction to {\phi} ~ {\pi} significantly reduces the critical field at which the zero-bias peak appears, with respect to {\phi} = 0. The phase and magnetic field dependence of the zero-energy states is consistent with a model of Majorana zero modes in finite-size Josephson junctions. Besides providing experimental evidence of phase-tuned topological superconductivity, our devices are compatible with superconducting quantum electrodynamics architectures and scalable to complex geometries needed for topological quantum computing.

https://arxiv.org/abs/1809.03037

So it looks like back in September 2018 folks were closing in on what is required for fault tolerant quantum computing.

Finally, in the April 2019 paper (recent! how intriguing…) https://arxiv.org/abs/1904.08981, the authors describe “Tuning Topological Superconductivity in Phase-Controlled Josephson Junctions with Rashba and Dresselhaus Spin-Orbit Coupling”. From the abstract:

Recently, topological superconductors based on Josephson junctions in two-dimensional electron gases with strong Rashba spin-orbit coupling have been proposed as attractive alternatives to wire-based setups. Here, we elucidate how phase-controlled Josephson junctions based on quantum wells with [001] growth direction and an arbitrary combination of Rashba and Dresselhaus spin-orbit coupling can also host Majorana bound states for a wide range of parameters as long as the magnetic field is oriented appropriately. Hence, Majorana bound states based on Josephson junctions can appear in a wide class of two-dimensional electron gases.

https://arxiv.org/abs/1904.08981

So it seems that there has been an alternative architecture proposed. The people involved also do not seem to be Microsoft related, but a different collaboration. Where was this alternative architecture originally proposed? Unclear, nonetheless, searching for references to “Rashba”, we are led to this part of the paper:

[Regarding implementing architectures to manipulate a 2D electron gas], among these proposals, those based on phase-controlled Josephson junctions with Rashba SOC [see Fig. 1(a)] offer an attractive alternative.37,38,42–47. Here, the interplay be-tween an in-plane Zeeman field parallel to the super-conductor/normal (S/N) interfaces, Rashba SOC, and the Andreev bound states formed in the normal re-gion induces topological superconductivity with Majorana bound states at the ends of the junction .

https://arxiv.org/abs/1904.08981

So it appears nothing fundamentally new here, just consolidation in the field as other teams replicate results.

Interesting area to watch, but the key takeaway for me is from https://arxiv.org/abs/1809.03037:

Besides providing experimental evidence of phase-tuned topological superconductivity, our devices are compatible with superconducting quantum electrodynamics architectures and scalable to complex geometries needed for topological quantum computing.

Together with advances from the new field of twistronics potentially unlocking the potential for room temperature superconductivity, this is looking tremendously interesting indeed.

April 20, 2019

## Synopsis

I touch briefly on the following topics in turn:

• [Agriculture] Mechanised Agriculture (and robotics)
• [Energy] Solar energy from deserts
• [Agriculture] Cellular agriculture
• [Computing] Tensorflow probability
• [Energy] The third wave of renewable deployment
• [Personal Projects] My current research in mathematics
• [Computing] Thoughts on Godot
• [Energy] Fusion power
• [Rocketry] Reaction Engines Limited
• [Personal Projects] Forays into running my own web services
• [Computing] Topological quantum computing
• [Water] Status of work on desalination

## Mechanised Agriculture

### The opportunity

• Automation of mechanised agriculture by artificial intelligence and robotics has the potential to allow a number of benefits, including: massively scaling farmsteads to larger regions, being able to farm previously non-arable land, optimised crop rotation, better soil maintenance and care, micro-control of weeding, spraying, reduced list of pesticides, micro-management of pruning and harvesting.
• Productivity gains for farmland is a certainty. Increasing the amount of arable land is also a certainty.
• Also interesting is whether this sort of farming could be adapted for vertical farming practices as well.

## Exporting solar generated energy from large desert regions to regions with less solar production

### The opportunity

• Places like the Sahara and the centre of Australia have low population but have significant amounts of solar energy falling on them.
• Building solar power plants in these places and then building high voltage power lines would be a way to boost the economy of the region by shipping electricity to places of high population density but with lower amounts of solar energy falling on them.

## Meat grown in the lab

### Other implications

• Decrease of need for land to be used for raising cattle.
• Reduced methane emissions.
• Ability to release land for national parks or alternatively use it for other forms of agriculture.
• Being able to grow other types of meat like fish, which has implications for preservation of fisheries and maintenance of biodiversity in the oceans.

## Tensorflow Probability

https://github.com/tensorflow/probability

### Why this is cool

• Probabilistic programming for machine learning.
• Builds on top of tensorflow.
• Can run in colaboratory.
• Supports a wide variety of different ways of testing the efficacy of a machine model at runtime.

### How this could be used in production systems

• Could determine whether or not a prediction is reliable, or whether the meta-model in a reinforcement learning problem (eg a self driving car, or a chat bot cough, Duplex, cough) should stop and seek for more information.

### Implications for testing machine learning models

• I see the main application in deep reinforcement learning, but there are other opportunities for carefully evaluating the efficacy and/or suitability of different models against a particular duo of train and test datasets.
• One could potentially start building pipelines to ‘test’ models against particular instances at runtime, particularly when a model might have become stale.

### Other implications for data science

• As mentioned before, I’d be very interested to see how this could be used in reinforcement learning.

## The ‘third wave’ of renewables

### “the only limitation is ‘how fast can we deploy?'”

• At this point, replacement of fossil fuel generation from an economic perspective becomes a bit of a no-brainer.
• It is estimated that by 2030 there will be nowhere in the world that this no-brainer will not apply.
• Things may eventually start to plateau once renewables reach 40-60% of base generation due to seasonal or diurnal cycles of power availability. However batteries are improving and becoming cheaper, too, and also there is the potential for shipping power internationally (eg from the Sahara to Europe, and from Australia to Indonesia).

## Current research, mathematics

### Type theory as a space of functions

• I have been exploring policy theory, which is most naturally thought of as endowing the space of classes of functions that take types and operate on geometry, to itself have a geometrical structure. This is a natural way potentially of unifying ideas about topology, geometry, and algebra, and extending them to the foundations of torus categories.

### Rather than data as geometry, code as geometry

• Wheeler talked about ‘It from Bit’ in terms of coining the interplay between information theory and physics, so that one could think of ‘data’ as being analogous to physical space (subject of course to appropriate conventions, definitions, and guardrails against reification fallacies of varifold types and flavours).
• However the exciting thing is that one could think of the programs that are acting on Bits to be somehow dual to theories acting on physical spaces. So some quite exotic potential directions to explore.

## Thoughts on Godot

### Status of the Godot project

2016
The sad truth is that, even after two years of being open source… NO ONE KNOWS ABOUT GODOT!
2017
Compared to last year, some more people had heard of Godot, but it’s still very largely unknown. We seriously need to consider ways to improve on this.
2018
I would probably say most of the industry still has not heard about it, but there is a very significant chunk that did, though.
2019 (this GDC)
From everyone we talked to, it seems at this point a majority of the industry has heard of Godot. Most of those we casually talked to definitely had heard of it and many expressed interest in developing games with it in the future

### Thoughts regarding cool things that could be introduced

• My hobbyhorse continues to be a procedurally generated D&D multiplayer sandbox and steps towards that.
• For this, being able to use an object picker in game to drag and drop things would be quite beneficial. I was quite excited by the possibility to vote on a tutorial for same in the recent Patreon voting for this month.
• This issue would be useful to explore: https://github.com/godotengine/godot/issues/19117 regarding Voronoi tiling and Lloyd’s relaxation. This link in a comment was particularly interesting as it revealed a wealth of resources across the web on procedural generation: http://www-cs-students.stanford.edu/~amitp/game-programming/polygon-map-generation/

### The need for testing and ensuring that technical debt doesn’t accumulate

• Technical debt always tends to accumulate, and as Godot continues to become more and more popular and crescendo past critical mass, there will need to be a continued effort to fight technical debt and prioritise this as roadmap items for the project.
• More unit tests, end to end tests, and other testing would be a good idea. The potential to run the Godot editor in a browser as a consequence of work being funded by the Mozilla foundation would potentially be a good opportunity for end to end testing or other forms of integration testing.

### The need to maintain minimalism in the UI and prevent code and feature bloat while maximising discoverability, documentation and flexibility / performance

• The reasons for Godot’s emergence as a compelling and competitive challenger to many established game engines are varied. One is that it is open source, but there are other value propositions that will need to be intentionally protected as the project continues to mature if it is, in my view, to continue to be a compelling engine.
• Performance, minimalism of UI and design, discoverability, and good documentation are key draws that pull people to the Godot project, and I think that these are things that should be protected.

## Fusion Power

### Wendelstein 7-x

• I believe that fusion product will become one step away from production ready in current experiments in 2019, and that Wendelstein 7-x will have reached its optimisation objectives either this year, or in 2020.
• Next steps include proposed next generation power plant HELIAS https://iopscience.iop.org/article/10.1088/0741-3335/58/7/074006 and/or working more closely to introduce Wendelstein findings into the ITER construction

### Iter consortium

• Inauguration of machine about 2025?

### What’s next?

• look to ITER
• look to HELIAS and next generation plans at Max Planck
• z pinch experiments at the University of Washington worth watching
• probably on track for first commercial fusion power plants conservatively by 2040 or 2045

## Reaction Engines Limited

### TF1 & TF2 progress

• TF1 construction and final fitout almost completed per my understanding
• Recent test in TF2 in Colorado passing (Mach 3 air temperatures / Blackbird speed)
• Recently announced collaboration with the National Composites Centre in the UK https://twitter.com/NCCUKinfo/status/1118800923147546624

### What’s on the horizon?

• I’d imagine a hotter temperature test in Colorado and/or at TF1
• Tests at TF1 starting in late 2019 or early 2020
• In 2020 things will get interesting

### rails

• Rails udemy course

## Forays into running my own web services

### email server

• interesting to investigate setting up an email server to reduce total reliance on two or three dominant cloud services
• advanced considerations including using sendgrid smtp relay service

• Good to customise one’s own news feeds to ensure that one doesn’t drown in irrelevant and/or ‘clickbait’ information

### voip / sip server & pstn investigations

• interesting to learn how to set things up with kamailio
• newer more developer friendly / modern architectures also starting to emerge like https://github.com/fonoster/routr
• flowroute or twilio as pstn integration services
• scaling to a business and how much one can charge, including the potential for profitability
• backing up data, failover, and ensuring production ready for running a voip server business

## Status of work on desalination

The use of large-scale desalination plants is posing an increasing threat to the health of the seas, a recent report from the UN University found. For every litre of freshwater created from a conventional desalination plant, an average of 1.5 litres of brine is also made.

The Guardian

Happy Easter!

## Merry Christmas!

December 26, 2018

Various things that I am looking forward to doing as hobby projects next year, or at least chewing over:

• Investigating building a procedural generation course in Godot on the Udemy platform
• Writing a paper on pyramid / 2-simplicial categories and submitting it to a mathematics conference (maybe Category Theory 2019?)
• Writing a paper on algebraic information theory
• Further afield (2025/2030+ ?), thinking vaguely about lens-categories, and 1-complexity reduction techniques. Such techniques are important if one wishes to construct control circuitry to solve field equations sufficiently quickly for precision control of fairly advanced technology, such as craft capable of practical and routine flight through interstellar space.

Things that I thought were really neat that have happened this year:

• Discovery of conventional superconductors with Tc conservatively at 250K (however, not at ambient pressure), with potential to find closely related superconductors with Tc up to 320K: https://arxiv.org/abs/1812.01561 . Exotic ‘high-Tc’ superconductivity still remains a mystery.
• Reaction engines have completed TF2 in Colorado USA and are on track to open TF1 in Westcott UK for testing in 2019: https://www.reactionengines.co.uk/news/building-momentum-our-development-programme . For a reminder, this company is researching technology that may reduce cost of payload to orbit from ~USD 10000 / kg to ~USD 100/kg (although I may be a bit wrong about the precise pricepoints).
• The Max Planck institute continued to set new records with their Wendelstein 7-X experiment (which is not designed to be a prototype power plant, but a stepping stone for plasma physics research along those lines), with a fusion product produced with temperatures up to 20 million Kelvin, and “high plasma densities of up to 2 x 10^20 particles per cubic meter – values that are sufficient for a future power station.” (Temperatures of 100 million Kelvin are needed for a power plant (to achieve ignition of the plasma), as well as continuous operation.) Further upgrades are to be made to the device over the next few years, by installing cooled carbon tiling (I think), allowing the stellarator to potentially achieve continuous operation (and certainly pulses up to 30 minutes). Current pulse duration achieved has been up to 100 seconds. In short, multiple records have been set by the Wendelstein 7-X team over the last year, and things are looking very promising: https://www.ipp.mpg.de/4550215/11_18

Various software projects that I am excited about include:

(Actually, I think that is the main software project that excites me at the moment, outside of work related ones)

In terms of yet other projects:

Merry Christmas! Here’s looking forward to many exciting, interesting and useful things happening in 2019!

## Various odds and ends

November 11, 2018

I recently discovered that there is an open source game engine called Godot. Having now listened to more than 40 lectures on how to use the engine by GameDev.tv, I can confirm that it is quite a useful piece of technology.

Also, I recently came across OpenAi’s ‘Spinning Up’ page from a blog post of theirs, here: https://spinningup.openai.com/en/latest/user/installation.html , in terms of getting started with the discipline of Deep Reinforcement Learning, a combination of Deep learning with reinforcement learning. They use MuJuCo for this, which requires a \$500 USD license (so probably not justifiable for random experimentation), however OpenAi also have an open source variant of the same sort of program here: https://github.com/openai/roboschool that, although probably not nearly as good, has the advantage of being opensource and free. They are apparently currently working on ‘roboschool 2’, which will represent a significant step forward on this project.

The FutureCrunch folks have posted three blog entries on the transition to clean energy globally, which represents four months of intensive research by said folks. There are approximately 2 hours worth of reading summed up in three blog posts:

FutureCrunch also informed me of the existence of this movie trailer: https://www.youtube.com/watch?v=MLcghUzzQCg based on a book of short stories ‘The Wandering Earth’ by Cixin Liu.

## Deploying a phoenix app to production, II

June 30, 2018

Consequent to my earlier investigations, I found that edeliver failed to provide what I needed to run a phoenix app in production – although I was able to have a brute force workflow to deploy something to a digital ocean server.

That too, was limited however, in that I was unaware as to how to run my app as a background process (daemonised).

Fast forward a bit, and I found an alternative deployment tool called bootleg: https://github.com/labzero/bootleg

I hence followed the following steps:

1. Added these dependencies to my mix.exs
{:distillery, "~> 1.5", runtime: false}, {:bootleg, "~> 0.7", runtime: false}, {:bootleg_phoenix, "~> 0.2", runtime: false}
2. Ran mix deps.get
3. Ran mix release.init
4. Modified .gitignore so that I was able to commit prod.secret.exs to my repo. Used environment variables instead
5. Modified deploy.exs:
role :build, "server_ip", user: 'root', identity: "~/.ssh/id_rsa", workspace: "/app_build" role :app, "server_ip", user: 'root', identity: "~/.ssh/id_rsa", workspace: "/app_release"
6. Modified deploy/production.exs:
role :app, [“178.128.34.45”], workspace: “/root/app_release”
7. ssh’d into my server and made sure those directories existed
8. mix bootleg.build
9. mix bootleg.deploy
10. mix bootleg.start

This turned out to be sufficient to deploy my app.

One last thing: I needed to set a blank password for my ssh key. Hopefully bootleg will fix this in a later release.

You can view said site at http://marbles.cthulu.tk:4000/.

## Deploying a phoenix app to production

June 25, 2018

I recently followed this tutorial: https://www.digitalocean.com/community/tutorials/how-to-automate-elixir-phoenix-deployment-with-distillery-and-edeliver-on-ubuntu-16-04 to deploy a phoenix app to production. Following the steps, I found that it was helpful in that it built my confidence in the following:

* scp to transfer files or folders to a server
* ~/.ssh/config to ssh into a server on digitalocean via an alias
* I learned about what nginx actually does, in that it is a reverse proxy – and what a reverse proxy actually is
* I learned about edeliver and roughly how it works in conjunction with distillery

However, I found that I failed to progress in the tutorial beyond the point of “mix edeliver upgrade production”. edeliver was failing to work for some reason.

Eventually I just gave up and following an alternative process which I’ve documented in a messy sort of way here (with references): https://github.com/token-cjg/spinning_cat/tree/master .

On personal computer:

* on personal computer, make and test a change
* push to github

On github:

* merge to master
* make a new release with tag ‘tag’

On production machine:

* wget the new release on production machine
* tar -xzaf
* cd spinning_cat_’tag’
* Install dependencies with mix deps.get
* Create and migrate your database with mix ecto.create && mix ecto.migrate
* Install Node.js dependencies with cd assets && npm install
* Start Phoenix endpoint with mix phx.server

This flow, although more convoluted and less streamlined, works.

However, in the process of doing this, I discovered potentially why I was stuck in the previous tutorial. Essentially, I was missing a few dependencies in order to run things directly on the production machine:

* curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash –
* sudo apt-get install -y nodejs
* sudo apt install npm
* sudo apt-get install gcc g++ make
* curl -sL https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add –
* echo “deb https://dl.yarnpkg.com/debian/ stable main” | sudo tee /etc/apt/sources.list.d/yarn.list
* sudo apt-get update && sudo apt-get install yarn
* sudo apt install nodejs-legacy
* sudo apt-get install inotify-tools

However, I as have yet not tested this.

So I guess, next steps here:

* See if I can get edeliver working
* Learn properly about nginx reverse proxy

Then, further afield:

* Purchase a domain name
* Customise website

## Unity project progressions: 50% completion towards first roadmap item!

June 22, 2018

You may recall (well, likely not) that the last time that I wrote in detail (February this year was not in detail) about my Unity project was here: https://confusedgremlin.wordpress.com/2016/11/19/further-thoughts-regarding-unity-project/ (wow, 2016! has it really been that long?) and further back I wrote about roadmap items here: https://confusedgremlin.wordpress.com/2015/02/28/dungeons-and-dragons-video-and-alpha-brainstorming/ (in the dark depths of 2015 …).

In the 2015 post I mentioned:

Hence, it now becomes possible to start working towards a first version of my dungeons and dragons dungeon master style multiplayer game.  In particular, I think there are a number of things that I’d now like to do:

• Plumb in the multiplayer functionality from my previous project.
• Introduce a simple and straightforward database model for players and dungeon masters.
• Allow players to spawn in a world in an appropriate way (without falling forever).
• Allow the dungeon master to move players around.
• Allow the dungeon master to switch their camera to a creature under their control and move it around.

I realised pretty quickly that this was an ambitious task, and could take years to progress on.  Fortunately, due to the relatively recent acquisition of some code masterfully written by another developer, and due to the continued reworking of the Bolt multiplayer framework by Photon, I have finally made a small breakthrough.

You can see it in its full glory here:

Basically, I have succeeded in synchronising certain assets between different clients running an instance of a runtime level editor.  So pretty cool! (at least I think so).  Essentially very little done here on my behalf, merely mashing together two codebases (the bolt network library and some code I purchased from somewhere in the internet) until something fell into true.

I also found the BoltEngine cheatsheet extremely useful in this: https://docs.google.com/document/d/1CvN1E2GOvd_AHnkFOSMSJTR96EBGhPRDPgPMiOuJoSg/view#.

So in terms of the above objectives for the first milestone:

• Plumb in the multiplayer functionality from my previous project.
• Introduce a simple and straightforward database model for players and dungeon masters.
• Allow players to spawn in a world in an appropriate way (without falling forever).
• Allow the dungeon master to move players around.
• Allow the dungeon master to switch their camera to a creature under their control and move it around.

I suppose I could say that I’ve mostly met the first and second of these.  There is a little bit more work to do in synchronising textures and working on the client UI, as well as determining how much control a client should have over editing, and whether the host/server should determine privileges, but that is well on its way now – I’d say at least 50%, and maybe 75% done.

Next steps would be to provide the ability for clients to drag and drop avatar tokens (first person controller prefabs), and then provide them the option to select one of their avatars and ‘avatar in’ to first person perspective, then allow them to ‘avatar out’.

After that, more segregation of privilege work, in terms of:

• first figuring out how to allow client A to move certain entities around, which client B (which might be the same as A) has placed.
• then figuring out how to isolate this power to a particular client (which would likely be the server) iff A is not equal to B

But as you can see, this work is finally on its way!  Very exciting!  It only took three years =P

## Rewilding as the logical outcome of civilisation

March 18, 2018

I believe that a truly advanced civilisation should not be visible within the confines of an biosphere, at least per a modern human’s perception.

Consider human civilisation – from hominids roaming Europe, Asia and Africa hundreds of thousands of years ago, with modern-ish humans emerging about 100 thousand years ago, and modern humans about 20.  The first small agricultural communities, perhaps 10 to 15 thousand years ago.  The first cities and empires, 5 thousand years ago.  Industrialisation, about 300 years ago.

If risks are managed sensibly, I see that a logical steady state approach would be to seek not to over-extend use of resources, and restore if possible pre-existing ecosystems, or create new ones.

Likely, as with the move to cities, our descendants may likely move to city memory and only ‘avatar’ to one or multiple cyborg bodies if and when required.  Consequently, although cities may have several orders of magnitude more inhabitants, performing at a cognitive and intellectual level far beyond modern humans, their experiences and chosen interfaces will largely be virtual or simulated.  Moreover, such cities could essentially be much more compact than modern cities, as they would essentially be server farms with robotic maintenance infrastructure.  These might run on nuclear fusion or casimir pumps.

For reasons of ecotourism and keeping things tidy and ordered, such future civilisations spanning the globe and solar system may decide to let nature reclaim the large tracts of land previously given over to agriculture and more primitive infrastructure, in an ordered but apparently chaotic fashion.  This principle of ecological custodianship would possibly also seek to revive extinct species by first principles, or construct new ones if and as required to fill ecological niches and improve the aesthetic of the apparently wilder world.

Tunnels through space may well be constructed to transport the few goods and resources required for maintenance, obviating the need for traditional shipping (road, freight and rail).  Hence these could be left to decay and return to the wilds, or even deliberately dismantled.

Eventually a machine civilisation with citizens in city memory could potentially surgere off miniature pockets of reality for use, connected by one or multiple small umbilicals to base reality.  It seems likely at said point that at this stage Contact may well have been attained, and this civilisation would no longer be bound to the confines of our Solar System.  On Earth, devices to maintain said umbilicals would not need to be as large as the server farms running the prior cities.   Casimir pumps or more advanced forms of energy production would be consumed to power the civilisation.  Populations would continue to increase by several orders of magnitude over the previous machine civilisation, however the maintenance infrastructure and much of the relics of the machine civilisation would not be required.  Custodianship processes could accelerate, and managed gardening of the world by a branch of some part of the future government might pick up.  Apparent chaos would continue to increase.  Pocket universes with recreations of old cities might be generated for avatar tourism.

Miniaturisation and abstraction of umbilicals would continue.  Eventually, all interfaces between the base reality and said future civilisation would be essentially invisible to a modern human eye.  The entire planet would contain only the relics of prior settlement that the civilisation wished to leave or preserve.  Any copies for archaeological purposes would have long since been backed up at various levels of abstraction or recreated in pocket universes that might be smaller or larger than the base.  Everything else would be restored and wild.  Atmospheric gas concentrations would be carefully balanced, and ecosystems would be designed to be as stable as possible with negligible intervention.

Consequently if a modern human were to step into a time machine and emerge on Earth say at some sufficiently distant point in the future (700 years?  1500 years?) they could well see no sign of civilisation at all.  However, it would be there, running at a level of sophistication and subtlety well beyond the wildest predictions of such writers as H.G. Wells.

## Various Projects, Status & Rundown

February 27, 2018

Here is a brain dump of my various projects, and progress to date on them.

Unity 3D game

• I was enthused to learn that Unity-Technologies have taken over development of GILES as of 12 days ago (which was originally a ProCore3D project), here: https://github.com/Unity-Technologies/giles .  I have updated my copy of GILES to run against Unity 2017.3.1
• I have been furthermore encouraged to learn that per https://forum.photonengine.com/categories/bolt-engine that BoltEngine is now almost up to speed with the latest Unity, and that there will be a Sample Pack released soon (which should make my job of adapting the tech to my purposes simpler).

Phoenix/Elixir app

• I have started playing around with Phoenix.  My current goal is to build a scaffold for an app where users can submit billboards, with topics, with posts, with attachments.  The data layout for this has largely been done and instantiated via ecto/postgres.  Hopefully I can progress this further by building out the controllers and the views over the next month or two.

• I have been spending some time learning a bit about android, in particular, Facebook app development.  My goal is to build an app that can query the graph api, and only extract and present data to me that I care about from Facebook.  This will have a couple of benefits to me – 1, that Facebook will become useful to me again, and 2, it will provide me with practical knowledge in terms of building Facebook apps.
• Currently I have built a normal Android app, as well as a Facebook app placeholder.  However I am finding that there is a namespace conflict between the two apps; likely I will need to start a new project from scratch, rather than copying and then editing the namespace by hand.  Also, I intend to remove the need to ask for permissions from the app; I dislike apps that ask for permissions they do not need.

• I’m currently reading the very approachable Introduction to Statistical Learning (http://www-bcf.usc.edu/~gareth/ISL/), and doing the exercises in R.  My goal is to work my way through this book, and make a start on Elements of Statistical Learning, before looking into potentially undertaking a microdegree or two later this year.

Language Learning

• I’ve been trying to learn a bit of French by working my way through the Michel Thomas course on same.  I’ve worked my way through the audio course once now; I will aim to work my way through it one or two more times before the end of the year.
• I’m thinking of learning a bit of German the same way, with the sibling Michel Thomas course.
• My goal by the end of 2019 is to be able to read Le Monde to a degree (http://www.lemonde.fr/) as well as Der Spiegel (http://www.spiegel.de/)

Research project, arithmetic topology

• Preliminary progress has been made.  This is largely on the backburner for now, but I should probably make a bit of an effort to properly write up what I have at some point.

## Vertical farming: practical with fusion power

September 17, 2017

Vertical farming has the potential to provide a number of advantages over conventional farming:

• Cut down on supply chain costs
• More efficient use of land
• Rewilding of large amounts of wilderness outside of cities
• Fresher produce more readily available

However, there is a bit of a problem – the energy expenditure required to make it practical renders it more expensive to grow crops in skyscrapers, both economically and environmentally, than conventional farming.  Wheat requires a large amount of energy to grow, as do legumes.

However, if, with any luck, we have the ability to construct workable nuclear fusion power plants by 2030, the nature of the game changes, as we would have readily available much cheaper, cleaner energy than through other power sources (with the exception of the Sun, which is also, of course, providing energy emitted by nuclear fusion).

If such does become practicable, large amounts of existing land given over to farming could be returned to the wild, and established as national parks and nature reserves.  This would be greatly useful, as it would allow us to allow the lungs of the world to regenerate, as well as providing large areas for ecotourism for city dwellers to appreciate on a more primal level.

Management of the cutover from large scale agricultural operations to vertical farming would be likely to take decades, but I could imagine that by 2070 or 2080 it should be possible to return a fair amount of land to the wild.