### Archives For EmQM

This is a paper version of the poster I presented at EmQM17 in London.

Abstract:

Some physicists surmise that gravity lies outside of quantum mechanics. Thus theories like the standard semiclassical theory of quantum to gravity coupling (that of Rosenfeld and Møller) are possible real models of interaction, rather than a mere approximation of a theory of quantum gravity. Unfortunately, semiclassical gravity creates inconsistencies such as superluminal communication. Alternatives by authors such as Diósi, Martin, Penrose, and Wang often use the term ’stochastic’ to set themselves apart from the standard semiclassical theory. These theories couple to fluctuations caused by for instance continuous spontaneous localization, hence the term ’stochastic’. This paper looks at stochastic gravity in the framework of a class of emergent or ontological quantum theories, such as those by Bohm, Cetto, and de Broglie. It is found that much or all of the trouble in connecting gravity with a microscopic system falls away, as Einstein’s general relativity is free to react directly with the microscopic beables. The resulting continuous gravitational wave radiation by atomic and nuclear systems does not, in contrast to Einstein’s speculation, cause catastrophic problems. The small amount of energy exchanged by gravitational waves may have measurable experimental consequences. A very recent experiment by Vinante et al. performed on a small cantilever at mK temperatures shows a surprising non-thermal noise component, the magnitude of which is consistent with the stochastic gravity coupling explored here.

Stochastic Gravity and Ontological Quantum Mechanics

I’m headed to London for the EmQM 2017 conference Oct 26 – 28 2017, which will I am looking forward to.

I attended in 2015. The event has the byline – the 4th International Symposium about Quantum Mechanics based on a »Deeper Level Theory«. Its mission this year is

```Towards Ontology of Quantum Mechanics and the Conscious Agent
David Bohm Centennial Symposium```

When I first really understood what quantum mechanics really was – in second-year undergrad at the University of Toronto, I immediately read all sorts of books and papers by and about Bohm’s theories. He made quite a change in my outlook of physics in general. I became convinced in 1985 that quantum mechanics was incomplete and that something along the lines of Bohm’s theory was the way to go. That makes the conference more special for me, and I’m sure many other attendees share the same view.

I am presenting a poster which I’m still polishing that up right now (the abstract at least was well received!). Its based on a paper called ‘Fully Classical Quantum Gravity (see link)‘. I have renamed the poster to Stochastic Gravity and Ontological Quantum Mechanics and rewritten most of it.

The poster describes the results of a paper by Vinante et al. :

Improved noninterferometric test of collapse models using ultracold cantilevers . If the results hold up, they are quite breathtaking as they state:

```

The finite intercept, clearly visible in the inset of Fig. 3 implies that the data are not compatible with a pure thermal noise behavior, and a nonthermal ex-cess noise is present.```

The paper details the careful procedures followed to chase down possible experimental problems. The analysis is carefully thought out. The paper claims the results show a possible signature of Adler’s Continuous Spontaneous Localization (CSL), but to me it seems like if the results hold up that its simply a great puzzle to solve! My take (in line with the ‘Fully Classical Quantum Gravity‘ paper) is that this noise is caused by the continuous emission and/or absorption of gravitational waves at nuclear frequencies.

Gravitational waves are notoriously hard to see, and these high-frequency ones (HFGWs) even more so. Indeed, since gravitational wave power goes with the square of frequency, truly tiny values of the gravitational wave strain ‘h’ (h == 0 in flat space and h < 1) make for large energy fluxes. The LIGO observations saw gravitational waves with $h \sim 10 ^{-2}$ . The formula for the flux of a gravitational wave is:

So LIGO can see gravitational waves with a flux of about $1^{-3} watts/m^2$, while at nuclear frequencies like $10^{15} Hz$, the same formula yields an incredible $10^{19} watts/m^2$ – another way to look at that flux is that it represents 400+ kg! of mass per square meter per second! I propose that results like this suggest that matter itself can be made of nothing but elaborate patterns of gravitational structures. Clearly, high-frequency gravitational structures can hold an incredible amount of energy.

Another way of thinking about this result is that anytime a better telescope is built, or one is built that looks at a new wavelength, field or pattern of signals, those signals are not only discovered, they produce deep new insights about our universe. The fact that HFGWs are hard to detect does not mean that they are not there! Indeed, instead of calculating what the flux of HFGWs might be around us, we should instead admit our ignorance and calculate what we don’t know. Huge amounts of gravitational wave energy could be whipping by everything right now and we would not know a thing about it.

It’s going to be a quick few days in London!

–Tom

### The Atomic World Spooky? It Ain’t Necessarily So!: Emergent Quantum Mechanics, How the Classical Laws of Nature Can Conspire to Cause Quantum-Like Behaviour

The hardcover is out – for example here: Amazon.com  or at Springerbut its coming out in paperback soon – Amazon.ca . Its not coming in paperback, so I just bought the hard cover. Its ok if a paperback comes later but I can’t wait!

So what I’m saying is that I’m cheap enough to wait for the paperback, so I actually have not read the book, but it looks like its going to be a real addition to the field. Its aimed at people with at least a science background.

The book takes the discovery (by for example Couder/Bush) that quantum-like behaviour is not solely reserved to atomic particles one step further. If electrons are modelled as vibrating droplets instead of the usually assumed point objects, and if the classical laws of nature are applied, then exactly  the same behaviour  as in quantum  theory is found, quantitatively correct! The world of atoms is strange and quantum mechanics, the theory of this world, is almost magic. Or is it? Tiny droplets of oil bouncing round on a fluid surface can also mimic the world of quantum mechanics. For the layman – for whom the main part of this book is written – this is good news. If the everyday laws of nature can conspire to show up quantum-like phenomena, there is hope to form mental pictures how the atomic world works.

Here is an excerpt from the Preface to the book: (other tidbits can be downloaded from Springer)

```To begin with a warning: the contents of this book may be controversial.

The readers the author had in mind when writing this book are interested laymen, typically the kind of reader who searches bookshops for the latest popular-scientific books on developments in cosmology, on recently found fun- damental particles, or on the ever more magical findings of quantum physics. These readers presumably have some background of classical school physics (although most of it may have been forgotten). It is the kind of reader who does not like to be bothered with formulae or is even allergic to them, but who has the interest and tenacity to read sentences twice if necessary. But complete novices in the matters of the atomic world should be warned: the stories told in this book are not the same as usually found in books about quantum phenomena. This book does not give the conventional explanations. In order to read the usual stories, it is better to start in

one of the many other popular-scientific books.
What then is this book about? This book certainly does not pretend to contain a

new theory of quantum mechanics, nor does it have the intention. Quantum theory in its present form is an almost perfect tool to calculate the behaviour of elementary particles. But the theory is “strange”, it is not something that intuitively can be understood. What this book tries to add are visualisations or mental pictures, closer to the intuition, because they are based on classical physics. However, the mental pictures in this book are not just half-baked analogies or metaphores, they are solidly founded on a large body of mathematical theory (for the diehards: the theory can be found in the appendix). This aspect makes this book different from other popular-scientific books.```
Here is an excerpt from the book’s appendix. You can see that a mathematical treatment is supplied. This book is written for people who already know QM. I can think of some young physics undergrads I might buy this for!
I will do an in depth review when I’m able to get the book.
–Tom Andersen

An interesting popular article that I found in Quantum . My favourite quote:

But there’s another view — one that’s been around for almost a century — in which particles really do have precise positions at all times. This alternative view, known as pilot-wave theory or Bohmian mechanics,

##### New Support for Alternative Quantum View

An experiment claims to have invalidated a decades-old criticism against pilot-wave theory, an alternative formulation of quantum mechanics that avoids the most baffling features of the subatomic universe.

I really like this graphic – visit the story for more!
Emergent quantum mechanics comes in many forms: stochastic electrodynamics ( Ana María Cetto) , de Broglie – Bohmian mechanics (John W M Bush) , thermal models ( Gerhard Groessing ) etc. In many of these forms of emergent quantum mechanics, particles have a physical existence and experience sub quantal movement. The paper I have just posted looks at the gravitational consequences of this sub quantal motion. An interesting finding is that while a classical Bohr hydrogen atom has a lifetime of about 10^-11 seconds, it would take that same atom 10^40 seconds or so to radiate away a few eV of energy. This indicates that the stability of the atoms is not an indication that gravity needs to be quantized, which is antithetical to Einstein in 1916:
• “…Nevertheless, due to the inner-atomic movement of electrons, atoms would have to radiate not only electro-magnetic but also gravitational energy, if only in tiny amounts. As this is hardly true in Nature, it appears that quantum theory would have to modify not only Maxwellian electrodynamics, but also the new theory of gravitation.” – Einstein, 1916
Einstein it would seem was wrong on the gravtitational side of this.
The paper looks at possible ways to see these tiny emissions (nuclear scale emissions are higher) and thus lays out a quantum gravity experiment achievable with today’s technology.

The experimental parameter space. Most important thing to note is that this is a quantum gravity experiment with an achievable parameter space!

Here is the paper…

Also see these references…

In this two page paper, I look at how the relationship between the dimensions of a Kerr singularity and the strength of the electric Coulomb effect compare.

Continue Reading...

#### Podcast Link

Ian Sample has a 38 min talk with Gerard t’Hooft about a paper he presented at EmQM2011 in Vienna. The EmQM conference is held every two years, in 2015 I presented a poster called Can a sub-quantum medium be provided by General Relativity?. He also chats with Kings College London’s Dr Eleanor Knox, for some historical perspective, and Professor Carlo Rovelli for a bit about the, relational interpretation of quantum mechanics.

Ian writes

`The 20th century was a golden one for science. Big bang cosmology, the unravelling of the genetic code of life, and of course Einstein’s general theory of relativity. But it also saw the birth of quantum mechanics – a description of the world on a subatomic level – and unlike many of the other great achievements of the century, the weird world of quantum physics remains as mysterious today as it was a century ago. But what if strange quantum behaviour emerged from familiar, classical physics? How would this alter our view of the quantum world? And, more importantly, what would it tell us about the fundamental nature of reality?`

Some notes while listening…

1min The Podcast starts off with Feynman’s guess snippet. Which is as funny as it is right.

2min That is followed by a very short well known (to quantum mechanics like us) intro to quantum mechanics.

4min Then – Ian actually uses the words ‘Emergent Quantum Mechanics’!

5-7min Gerard talks about the accuracy and weirdness of quantum mechanics.

8min Gerard  – “Classical Physics is an approximation.” – not incompatible.

8min Ian brings out ‘God does not play dice’.

9min Knox – talks about the measurement problem. The collapse. The Copenhagen Interpretation.

10min Knox talks about emergent theories – like biology, thermodynamics. So is quantum mechanics emergent? – Will EmQM help with the measurement problem?

13min Gerard – perhaps the randomness of QM does arise from stochastic classical actions. The answer is no – its not classical – “its different to its bones” from classical. Its a fundamental difference. (i.e. Bell).

15min Gerard talks about the Standard Model of Particle Physics. – Lots of people think that is all we need.

16min Gerard says the SM+QM does not feel right. It lacks a certain internal logic. Gerard thinks that the laws of QM are something of an optical illusion, ‘what is it actually that we are describing’.

17min Gerard does not want to change the equations of QM. He keeps the equations of QM. (Tom says this is at odds with most EmQM practitioners today).

18-22min Ian asks if EmQM is controversial. Gerard says yes its controversial. Bell proves that its impossible to have a classical computer reproduce QM. But Gerard has looked at the small print, and finds a way around the Bell theorem – by long range correlations – linked. This correlation is the heart of QM and is not weird – but needs a natural explanation.

22min Ian asks if this solves ‘Spooky action at a distance’. Gerard says yes it does these correlations can explain these peculiar correlations.

23min Ian says Knox calls Gerards plan ‘superdeterminism’.

25min Ian asks why do we need to change QM if it works so well? Gerard says the positive outlook on QM as being exactly correct is the Many World Interpretation. Gerard finds MWI ‘unsatisfactory’.

26min Ian points out that Gerard and EmQM are controversial.

27min Ian talks to Carlo Rovelli.

28min Carlo says we need to get used to QM – it will not be explained or overturned soon. The weakness in EmQM’s are that they do not lead to ‘new ways of thinking’ (Tom says what??). Then he talks about String theory and QM. We should just accept it as is.

30min Ian talks to Gerard about being comfortable with a theory that like QM. Gerard says that the present situation is bad with the MWI multiverse. Gerard thinks that while this works its ‘unsatisfactory’.

31min Gerard – the MWI shows that we are not there yet. We have not found the right description for our universe. All we have today are templates – that is our description, but its not what it actually is.

34min Carlo – his relational theory. Which is not MWI. Take QM seriously, relational QM takes QM at face value. The properties of objects are always measured with respect to something else. Velocity is the property of an object relative to something else.

36min Carlo starts talking about quantum gravity. We need to use relational QM to help us get to quantum gravity.

37min Science is a long sequence of us discovering that we were wrong. The world is different. If we end up agreeing on QM then this changes realism and philosophy – which Carlo thinks that will be the case. QM is the final theory for him.