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alena lis: on 8/2/16 at 9:14am UTC, wrote Thanks for useful information!

Steve Dufourny: on 1/2/16 at 11:05am UTC, wrote I d like to tell you that I beleive humbly that I found the gravitation...

Steve Dufourny: on 12/22/15 at 21:12pm UTC, wrote Hello Georgina, I am going to see it soon,I am persuaded that it will be...

Steve Dufourny: on 12/19/15 at 22:00pm UTC, wrote Be the force with you dear Jedis of the Sphere .......

Steve Dufourny: on 12/18/15 at 9:22am UTC, wrote This universal gravitation is an universal equilibrium probably linked with...

Steve Dufourny: on 12/17/15 at 11:27am UTC, wrote Dark matter is logically composed by particles of gravitation.I named them...

Steve Dufourny: on 12/14/15 at 10:53am UTC, wrote Furthermore, you imagine the % of this dark matter in our universe, we have...

Steve Dufourny: on 12/14/15 at 10:33am UTC, wrote If we have a sphere of spherons.It is important to consider this matter...


Georgina Woodward: "Perhaps the idea of consciousness causing collapse is being overthought? ..." in Consciousness and the...

Lorraine Ford: "Stefan, I would say that we individual human beings, and the rest of the..." in The Present State of...

Lorraine Ford: "Markus and the other participants, Isn’t there something very wrong with..." in The Room in the Elephant:...

Georgina Woodward: "Thank you John. What did you think about the questioning whether altitude..." in The Nature of Time

John Cox: "Sorry, Georgina, I have had a busy summer and am racing the change of..." in The Nature of Time

Jim Snowdon: "If the Earth did not have it`s rotational motion, the apparent time of day..." in The Quantum Clock-Maker...

Steve Dufourny: "Yes indeed the present seems the only one thing where we can insteract ,..." in The Quantum Clock-Maker...

Stefan Weckbach: "Hi Lorraine, thanks for your reply. You are correct, that's what I was..." in The Present State of...

click titles to read articles

Reconstructing Physics
New photon experiment gives new meta-framework, 'constructor theory,' a boost.

The Quantum Engineer: Q&A with Alexia Auffèves
Experiments seek to use quantum observations as fuel to power mini motors.

The Quantum Clock-Maker Investigating COVID-19, Causality, and the Trouble with AI
Sally Shrapnel, a quantum physicist and medical practitioner, on her experiments into cause-and-effect that could help us understand time’s arrow—and build better healthcare algorithms.

Connect the Quantum Dots for a New Kind of Fuel
'Artificial atoms' allow physicists to manipulate individual electrons—and could help to reduce energy wastage in electronic devices.

Can Choices Curve Spacetime?
Two teams are developing ways to detect quantum-gravitational effects in the lab.

September 26, 2021

CATEGORY: Blog [back]
TOPIC: Detecting Dark Matter Using Space-Based Quantum Optics [refresh]
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FQXi Administrator Zeeya Merali wrote on Mar. 25, 2015 @ 11:26 GMT
View from the conference centre, Erice
I’m lucky enough to be attending a COST Action workshop on quantum foundations currently taking place in Erice, Italy, with lots of FQXi folk in attendance. (Thank you to the organisers, FQXi’s Angelo Bassi, Catalina Oana Curceanu and Detlef Duerr and the meeting’s sponsors for inviting me.) I’ll keep you posted on the highlights throughout the week (and beyond, with a few podcast specials in the works).

Much of the first day was taken up with discussions of matter-wave interferometry. Quantum mechanics tells us that the boundary between waves and particles is murky at small scales. But just how far does this ambiguity stretch? Markus Arndt and Jonas Rodewald of the University of Vienna, and James Bateman, of Southampton University, opened the meeting by talking about ways to test whether ever-larger particles display quantum properties such as superposition, the ability to be in two places at the same time, for instance. (Bateman works with FQXi member Hendrik Ulbricht and you can read more about Ubricht’s Southampton tests of the quantum limits in an article written by reporter Sophie Hebden.)

Bateman’s talk particularly caught my attention when he mentioned plans to put such quantum experiments in space to try to detect dark matter. Although we have good evidence for the existence of dark matter — which is invisible but exerts a gravitational pull on other matter — from astronomical observations, physicists still do not know what it is and have devised numerous clever experiments to try to detect it directly and help identify it.

The inspiration to link dark matter to quantum optics came from an intriguing suggestion in 2013 by C. Jess Reidel that dark matter could be causing decoherence in matter wave experiments (knocking fragile quantum objects and causing them to lose their nifty quantum properties). As Reidel said in the abstract to a paper in Phys. Rev. D: “The apparent dark matter wind we experience as the Sun travels through the Milky Way ensures interferometers and related devices are directional detectors, and so are able to provide unmistakable evidence that decoherence has Galactic origins.”

It was a provocative notion and Bateman and co decided to investigate further. “This was an interesting idea, but essentially none of the details had been worked out, so we started talking to theoretical particle physicists,” Bateman told me. Those theoretical physicists were initially dismissive, but together with the experimental team, they came up with a candidate dark matter particle that would have evaded detection by dedicated collider experiments and would not have shown up in high energy collider experiments, but might show itself in a matter-wave experiment.

It turned out that this candidate could not actually be the decoherence mechanism in any existing matter-wave experiments, says Bateman. The hypothesised particle has a mass of about 0.02 per cent of the electron. “It is very low mass, which means its de Broglie wavelength” — the wavelength associated with quantum particles — “is large compared with the nuclei in normal matter,” Bateman explains. This means that it coherently interacts strongly with normal matter — so much so that “it couldn’t penetrate Earth’s atmosphere, let alone the glass and metal vacuum chambers of, for example, Markus Arndt’s interferometers,” says Bateman.

It’s not too much of a disappointment, though. A dark matter decoherence mechanism, despite sounding cool, isn’t that different from other decoherence mechanisms, in which the environment interacts with a quantum system, destroying its fragile properties. So, notes Bateman, even if it had worked in theory, it wouldn’t have magically solved the quantum measurement problem in a new way.

But this still left open the exciting possibility that a quantum optics experiment carried out beyond the atmosphere could be sensitive enough to pick up signs of this particle. The team outlined such an experiment in a paper published in Scientific Reports, involving a suspended nanoparticle. The way in which the nanoparticle’s position changes will tell them something about dark matter.

Scientific Reports
The idea is to place the experiment in a spacecraft located at Lagrange point 2 (a stable point in our solar system beyond the Earth). The nanoparticle’s position can be precisely tracked by firing laser light at the particle and collecting it with a lens. Light that has been scattered by the particle will interfere with the rest of the laser light, changing the intensity of light picked up by detectors, in a way that can be precisely monitored. (Image from Scientific Reports 5, article number: 8058, courtesy of James Bateman.)

The team plans to send the experiment into space as part of the MAQRO (microscopic quantum resonators) consortium. You can read more about space-based quantum tests in a Q&A that reporter Colin Stuart carried out with David Rideout and in an article that I wrote for Nature about the quantum space race between China and Europe.

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Akinbo Ojo wrote on Mar. 27, 2015 @ 13:54 GMT
Cherry picking 'facts' or 'possible facts' for your conference deliberation...

Whereas it is widely accepted that we have good evidence for the existence of dark matter — which is invisible but exerts a gravitational pull on other matter — from astronomical observations,

Whereas C. Jess Reidel in the abstract of his Physical Review paper categorically states that we (a...

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FQXi Administrator Zeeya Merali wrote on Mar. 27, 2015 @ 19:09 GMT
Hi Akinbo,

Thanks for your comment. As I understand it, Bateman and co did take Reidel's proposal very seriously but -- as far as their analysis showed -- it couldn't work. I'll ask Bateman if he can elaborate on that.

Regarding the waste of money, I think that MAQRO will involve multiple tests of different things -- so it will be a case (as it often is with space-based experiments) of trying to get as much information about a number of different things, using various instruments, in the most efficient way.

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Steve Agnew wrote on Mar. 28, 2015 @ 17:07 GMT
It is useful to consider the search for dark matter in the context of the larger search for a quantum gravity. Quantum gravity should scale nicely from the quantum charge force that we already know works very well, just reduced by 1e39. There seem to be an overwhelming number of propositions about possible quantum gravities and likewise, an overwhelming number of propositions about dark matter as...

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Akinbo Ojo wrote on Apr. 16, 2015 @ 11:38 GMT
Scientists say they have seen dark matter signs for first time

Scientists say they have seen for the first time signs of dark matter interacting one billion light years away.Dark matter is how science describes the mysterious substance that makes up most of the universe.A team of international researchers used the Hubble AND the European Southern Observatory space telescopes in their findings.

Also Dark Matter Can Interact With Itself, Galaxy Collisions Show

Dark matter interacting gravitationally everywhere, but surprisingly none is said to be available to form a light-carrying, gravitationally bound medium on our very tiny blue planet!!


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Steve Dufourny wrote on Sep. 14, 2015 @ 11:26 GMT

Dark matter logically is produced by our cosmological black spheres,our BH.

It exists if I correlate with my humble équations several kinds of Black matter considering the volumes of spheres.The smallest are from the central BH sphere of our universal sphere,the biggest cosmological spherical volume.

The quantum entanglement is in the same relative logic with an...

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Steve Dufourny replied on Sep. 15, 2015 @ 11:03 GMT
Xmass experiment seems relevant.

There are two possibilities in fact,it is easier to try to find them Inside our quantum entanglement because theye are also encoded these particles.

Xmass is relevant but it is more difficult in this way considering that these particles come from the black cosmological sphères.

It isthe same logic that with the bosons in fact but more difficult due to stepsof encodings which are more complex.Indeed it is a new kindof encoding and energy.The separation, the fission so are more interesting at my humble opinion.

The big question is how to separate them from our quantum entanglement.If thermodynamics is correct for these particles, ok but if the thermodynamics is not theroad, it is not sufficient because it is an other kind of energy aboveour thermodynamicallaws...

my équations if they are correct can help considering thevolumes and the motions rotations of sphères.I am persuaded that the spherical cosmological volumes and quantum volumes are the keys ...


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Steve Dufourny wrote on Dec. 12, 2015 @ 18:41 GMT

It is a beautiful article.This dark matter is intriguing and we know that its exists .I am asking me if we can consider it in the same way than our special relativity and the standard model also.Let's imagine a galaxy, let's imagine a central supermassive BH , a central sphere.Now let's imagine a sphere of dark matter encircling this galaxy.If this matter exists, so this matter has a cause of creation.They are produced in logic like is produced our bosons photons by stars.If now we consider that theseparticles aren't bosons.Let's name them the spherons.If now we link with the spherical volumes, it becomes relevant.If my constant is correct ,so their linear velocity is more than c and correlated withspherical volumes.The central BH of our universal sphere sHello o creates thesmallest spherons andthe speedest.See that this centralBH is the biggest cosmological volume.If now we superimpose the two sphères, one ofgravitation with these spherons and the other with photons.So we have a biggest sphere for spherons.Now imgine that thee particles areencoded in our nucleis at and after 10^-35m in a kind of quantumdark matter implying quantum gravitation.The spherons explain the gravitation .We have so a gravitational universal newtonian aether from the central sphere BH producing so this infinite gravitation relativelly speaking.The time can be analysed with thes two sphères, photons and spherons,electromagnetic and gravitational.The spherisation and the gravitation are purelly linked with the rotating sphères and motions.Mass increases, gravitation increasesand the spherisation also.Entropy becomes mass and the equilibrium is the gravitation spherisation.....

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Steve Dufourny replied on Dec. 14, 2015 @ 10:33 GMT
If we have a sphere of spherons.It is important to consider this matter like non baryonic,and not Under the special relativity.The WIMPs of hot dark matter are not logically correct due to the fact that we are Under the thermo and heat and so Under our standard model.The WIMPs of cold darkmatter also so because are also Under th laws of thermo at very low temperature.The gravitation is an other quantun of Energy, gravitational instead of electromagnetic and thermodynamical.The spherons so must be particles non baryonic.With their volumes, small and their linear velocity before encoding in our nucleis,these spherons imply an incredible entropy.Now we have the explaination of gravitation in being encoded in our nucleis above our standard model.But how can we check this new energy.The mass of the sphere, its volume, its rotation spinal,orbital becomes relevant when we consider a main sense of rotation for the stability of quantum gravitation.This gravitation linked with spherisation increases due to this increasing of mass entropy.The encoding of bosons imply the electromagnetic thermodynamical step,the spherons them are encoded also with this quantumof gravitational energy increasing the uniqueness of the nucleus.Rotations, gravitation, sphères and spherisation are universally unified in a pure evolutive entropical irreversible Arrow of time.Fascinating this universal evolution of imrpovement of mass, consciousness and gravitation spherisation.Universe is a sphere and the central BH also in logic like all BH.If they exist these BH,there are reasons.They produce something it seems tome implying this gravitation and its universalequilibrium between all sphères, quantic and cosmol.

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Steve Dufourny replied on Dec. 14, 2015 @ 10:53 GMT
Furthermore, you imagine the % of this dark matter in our universe, we have 4,9 % of matter baryonic, and about 26,8 % of non baryonic matter,this dark matter.You imagine the potential of this entropy, disponible with these quanta of gravitational energy, the spherons.Gravitation seems infinte when we link it with the central BH of our universal sphere and the dark energy.This energy, garvitationalcan be transformed into works or thermo......The spherical volumes are the keys it seems to me.Baryons are a step, electromagnetic.The spherons and the quantum dark matter encoding these spherons are the others steps.Mass and gravitation are linked .....Thanks Newton :)

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Steve Dufourny replied on Dec. 17, 2015 @ 11:27 GMT
Dark matter is logically composed by particles of gravitation.I named them the spherons.But they can be classed also due to their spherical volumes.If our Universe is a sphere in spherisation and that we have a central sphere, the biggest BH.So if my equation is correct mlosV,so the spherons produced by this centralsphere are the speedest and the smallest.If an universal proportion exists between allphysical sphères,quant and cosmol.So we can class their linear velocities and their volumes.I don't see an other solution than these BH for the production of these particles.If gravitation is infinite, it is towards this central cosmological sphères.Entropy gives the main universalgravitational codes from this central sphere.This central sphere logically is linked with all others BH and also logically with the central sphères of our quantum serie encoding bosons and spherons.Gravitation is an universal equilibrium since the beginning.The main codes are gravitational.It is relevant to consider this dark matter encircling our galaxies, a sphere of spherons, a sphere of gravitation above our sphere of photons.The age of our Universe can be correlated witht the two sphères, photonic and spheronic.Entropy, gravitation and spherisation seems universally linked.They turn so they are .....

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alena lis wrote on Aug. 2, 2016 @ 09:14 GMT
Thanks for useful information!

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