Qubit Coherence Time Dream 20-03-2023

This dream came after watching Roger Penrose discus “before the big bang” on YouTube. He suggested that in a thermalized black body compliant universe evidenced by the cosmic microwave background energy spectrum where E=hν = mc2, time or inverse time, frequency, does not exist in the absence of matter. “Time” can be curved to “before” the big bang of our current universe. Similarly at an infinitely expanded universe full only of radiation, photons, time again has no meaning without mass.

The dream starts in the refreshment area or bar off a hall full of poster presentations at a “perimeter” conference on quantum and quantum computing. I am talking with a “famous” prof in his early forties and he is holding court to some post docs and post grads. He is skinny with a beard and unruly hair. He is white. As far as he is concerned, I am a nobody.

I say to him that if I have understood it correctly the biggest drawback for quantum computing is qubit coherence time and thereby quantum fidelity. He says yes.

I say that a qubit is a counter-entropic state artificially manufactured in matter in many systems. In these matter based systems tremendous cooling is required to prevent coupling to the nearby thermal bath states which tend to bring about dephasing and lack of fidelity for the prepared qubit. He agrees.

I say that is why they need fuck off big fridges to get close to absolute zero, which is again a counter entropic state when viewed more than locally. He agrees.

That dephasing happens on a temperature and proximity dependent time scale.

I say that thermodynamics is a property of matter and hence time, without matter entropy as no meaning, nor does thermodynamics.

I ask him why nobody is pursuing fast or ultrafast time domain quantum computing? He does not reply.

I say to him if the prepared qubit state is addressed before dephasing occurs, we can use time to outwit or outpace thermalization to bath. Time domain quantum computing could be the answer.

He nods.

I say that the other problem stems from the cycle time of write to zero of the matter involved in the prepared qubits. It should be possible to use a second pulse similar to the state preparation one to reset the qubit clock on a hundreds of megahertz laser repetition rate. We then have a prepare and subsequent write to zero even if the qubit state has been used or partially used in computation. The matter is then ready for us to contravene entropy by writing a qubit.

As the dream ends, I think that it is a fair way from Guru Rinpoche.

Things That Come Back to Bite You on the Bum

The devil is often in the detail.

There are several permanent records held on the internet: Patents, Companies House, and things like Scholar GPS. There are many more.

This is my GPS graph referenced today.

It is weird to see that from time to time someone might still cite one of my cobweb papers. I don’t know if an h-index of ~15 is any good or not.

Truth is we all leave paper trails, data trails which might come back to bite us on the bum. These days the world is very interconnected, what once might have lain hidden in a paper archive can be cross-linked and cross-referenced electronically. AI might be good at that. Data may be traded between organisations.

Scholar GPS says that I have 43 papers but there are more than that. Back a layer behind a Google search I am linked, in perpetuity, in the literature, to various individuals if only for a fleeting moment. My erstwhile affiliation is evidenced by the claimed institutional address.

Our answers on official documents are no longer in musty filing cabinets, they are electronic. Even paper here in France is converted into machine readable PDF. There are some things upon which I am very mindful for the need for accuracy, particularly in detail. These are tax and medical related. I would never make even a semi-manufactured insurance claim.

You never know when something might turn out to be important. A forgery in the heat of the moment could resurface, a lie in an official document could result in prosecution. False claims made to secure funding can be seen as fraud.

It was just a detail… ask party-Boris how details can impinge.

Family law in France differs significantly from UK, here the children can be liable for the care home fees of their parents, seems only fair if they get a slice of the property on death.

It is usually the things which we do not face or try to avoid which keep on coming back. Pretending that we don’t need to do anything is rarely a wise strategy. The universe has a habit of re-presenting the things which we sought to avoid or escape from.

Things that come back to bite us on the bum can be very, very persistent.

Molecular Quantum Computing Dream 10-07-2024

Here is this morning’s dream.

The dream starts in the middle of a city. I am to attend a meeting on molecular quantum computing. It is partially at my behest. In the meeting are several people who I once knew around 18 years ago. We are sat roughly in a circle behind two seater tables.

I say that in its current form quantum computing is very environmentally hostile because of the energy needed to build and cool. There is a murmur of scoffing. Ian says that I am right and reels of some figures in terms of tonnage of carbon dioxide. Others concur.

I explain that here, with our hundred trees and land, we are approximately carbon neutral.

I know that the people at the meeting are humouring me and that they are highly sceptical.

I say that history shows that the machines at the early stage of any technology cycle are very different from those of the technology which emerges.

It is likely that quantum computing will become more biological. A way will be found to overcome the high energy burden. It will involve molecular qubits.

In the dream I make a note to re-read a paper by XXX.

There will be some way as yet unimagined to open up a new way of thinking, a more organic neural form of quantum computing.

The meeting disperses, sceptical.

I go outside with Ant and he points up at a huge crane, they are doing some optical fibre communication experiment on the crane. He expects be to be impressed.

I wander off towards the tube station.

Dream ends.