Archives For EmQM

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.
Parameter space for a quantum gravity experiment.

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.

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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 writesscreen-shot-2017-02-11-at-12-25-45-am

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.

Re: https://www.theguardian.com/science/audio/2017/feb/09/is-emergent-quantum-mechanics-grounded-in-classical-physics-science-weekly-podcast