The vast body of scientific knowledge is a whole divided into three parts, or layers. The first falls under the name of empirical knowledge, and includes the descriptions and the results of all experiments ever attempted. The second part comprises the mathematical systematisations of those experiments and the rules to predict the outcomes of future ones, that is, the physical theories of Nature. There is also a third part, to which one may ascribe the abstract study of physical theories themselves, seen as mathematical and logical objects. The purpose of this blog post is to advocate the importance of this ‘meta-theoretical’ layer of knowledge from a conceptual and foundational standpoint, and to illustrate how it is possible to investigate it.
There is not a deep divide between science and arts. Rather the opposite! I have long been interested in unveiling links between these two seemingly distinct spheres of knowledge. Scientists are typically seen as rational beings who pursue the truth and are not afraid of dissecting the most beautiful manifestations of nature into a set of basic analytical rules, often formalised as mathematical equations, even going as far as reducing the feelings of love to a series of biochemical reactions. Artists, on the other hand, are often perceived as creative characters who synthesise and embellish emotions by expressing them in languages which touch deeper chords in humanity, such as music or imagery.
Yet for those doing science with a passion, beautiful equations are perceived as equally if not more touching than a work of art, and creativity is a fundamental requirement for reaching beyond the state of the art on our understanding of how the universe works. Similarly, an increasing number of artists resort to analytical methods to explore novel ways to communicate inner expressions of self. And let’s not forget that a streak of polymaths, in which a combination of scientific and artistic skills has resulted in universally acclaimed masterpieces which made history, can be traced back many centuries: Leonardo da Vinci is perhaps the brightest example.
Quantum Roundabout 2018 was the fourth iteration of a series of dedicated conferences looking at foundational mathematical topics within quantum physics.
The etymology of the conference stems from the so called “Magic Roundabout” on the outskirts of Swindon. This roundabout boasts five mini-roundabouts arranged around a sixth central anticlockwise roundabout. It was decided that such a strange junction could only be quantum in nature, hence the conception of Quantum Roundabout. Continue reading
How can we design experiments in quantum physics? Generally, the strategy involves using the vast knowledge amassed by quantum physics researchers and combining this with our intuitions and our creativity. This method has been fantastically successful over the years and has given us experiments that help unlock both the technological and the foundational magic of quantum physics. But it is not always easy. Quantum physics is notoriously counter-intuitive, so sometimes our intuitions are not a good guide for how best to design an experiment. And sometimes past experience is not always the best guide to creating novel new designs, particularly when our experiments intend to probe a new and untested area. But how else might we design quantum experiments? In a previous post we introduced a method we are developing that utilises techniques from AI, machine learning and meta-heuristics to design quantum experiments. In effect, we are letting computers design experiments for us.
To be more specific, our task is the following:
Given a set of quantum-optics experimental equipment, what is the best way of arranging the apparatus to create a quantum state with certain desirable properties? Continue reading
In recent years, there has been increasing concern that sometime in the future a super-intelligent AI will rise up, take over the world, and destroy all humanity. Is this a real concern? Or is it over-hyped science fiction, with no reasonable connection to reality? In this blog I will first argue that super-intelligence is possible, and then argue that if such an entity is created, it is a genuine possibility that it will indeed exterminate us all!
Why many worlds?
Quantum mechanics is often presented as being “our most successful theory ever”. Despite 100 years of stringent experimental tests it has never been proved wrong. It has been confirmed to an accuracy of 1 part in 1012 and has even now been tested in space-based experiments. It underlies much of modern technology, including pretty much the whole information and computing industry. And it has predictive power in an extreme range of scenarios, from the smallest constituents of our universe to a fraction of a second after the Big Bang. For these reasons, it seems reasonable to assume that quantum mechanics is correct, and does not need to be modified, at least not yet.
We can then ask the question: If quantum mechanics is correct, then what does it tell us about the universe? But before answering this, we should probe whether this is a reasonable question in the first place. Continue reading
This blog post follows on from a previous post, “What does quantum mechanics tell us about reality”, in which I tried to give a balanced and non-technical overview of some of the interpretations of quantum mechanics. In this post I will take a different approach: this will be a slightly biased, critical, and more technical follow-up. I recommend reading the earlier post first, but those already familiar with the interpretations of quantum mechanics should be able to dive straight into this.
In the Schrödinger’s cat thought experiment, a cat is placed in a box with a device that contains a radioactive atom and a vial of poison. If the atom decays, then the device is designed to release the poison, thus killing the cat. It is now well known that such an atom can be put into a state in which it has decayed, and not decayed simultaneously – this is known as a superposition state. Now, if this system is studied using the central equation in quantum mechanics, the Schrödinger equation, then the following result will be found: if the atom is in a superposition state, then this will lead to the cat being in a superposition state. The cat will be dead and alive simultaneously! Now suppose you open the box – what will you find? The Schrödinger equation again predicts that, if the cat was in a superposition of being dead and alive, then when you open the box you will also enter into a superposition. You will be in a superposition of either seeing the dead cat, whilst simultaneously seeing the alive cat.