Giant atoms could help unveil 'dark matter' and other cosmic secrets

January 6, 2017 by Diego A. Quiñones, The Conversation
Composite image showing the galaxy cluster 1E 0657-56. Credit: Chandra X-Ray Observatory/NASA

The universe is an astonishingly secretive place. Mysterious substances known as dark matter and dark energy account for some 95% of it. Despite huge effort to find out what they are, we simply don't know.

We know dark matter exists because of the gravitational pull of galaxy clusters – the matter we can see in a cluster just isn't enough to hold it together by gravity. So there must be some extra material there, made up by unknown particles that simply aren't visible to us. Several candidate particles have already been proposed.

Scientists are trying to work out what these unknown particles are by looking at how they affect the ordinary matter we see around us. But so far it has proven difficult, so we know it interacts only weakly with normal matter at best. Now my colleague Benjamin Varcoe and I have come up with a new way to probe dark matter that may just prove successful: by using atoms that have been stretched to be 4,000 times larger than usual.

Advantageous atoms

We have come a long way from the Greeks' vision of as the indivisible components of all matter. The first evidence-based argument for the existence of atoms was presented in the early 1800s by John Dalton. But it wasn't until the beginning of the 20th century that JJ Thomson and Ernest Rutherford discovered that atoms consist of electrons and a nucleus. Soon after, Erwin Schrödinger described the atom mathematically using what is today called quantum theory.

Modern experiments have been able to trap and manipulate individual atoms with outstanding precision. This knowledge has been used to create new technologies, like lasers and atomic clocks, and future computers may use single atoms as their primary components.

Individual atoms are hard to study and control because they are very sensitive to external perturbations. This sensitivity is usually an inconvenience, but our study suggests that it makes some atoms ideal as probes for the detection of particles that don't interact strongly with regular matter – such as dark matter.

Our model is based on the fact that weakly interacting particles must bounce from the nucleus of the atom it collides with and exchange a small amount of with it – similar to the collision between two pool balls. The energy exchange will produce a sudden displacement of the nucleus that will eventually be felt by the electron. This means the entire energy of the atom changes, which can be analysed to obtain information about the properties of the colliding particle.

However the amount of transferred energy is very small, so a special kind of atom is necessary to make the interaction relevant. We worked out that the so-called "Rydberg atom" would do the trick. These are atoms with long distances between the electron and the nucleus, meaning they possess high potential energy. Potential energy is a form of stored energy. For example, a ball on a high shelf has because this could be converted to kinetic energy if it falls off the shelf.

The Large Underground Xenon experiment installed 4,850 ft underground inside a 70,000-gallon water tank shield. Credit: Gigaparsec at English Wikipedia, CC BY-SA

In the lab, it is possible to trap atoms and prepare them in a Rydberg state – making them as big as 4,000 times their original size. This is done by illuminating the atoms with a laser with light at a very specific frequency.

This prepared atom is likely much heavier than the dark matter particles. So rather than a pool ball striking another, a more appropriate description will be a marble hitting a bowling ball. It seems strange that big atoms are more perturbed by collisions than small ones – one may expect the opposite (smaller things are usually more affected when a collision occurs).

The explanation is related to two features of Rydberg atoms: they are highly unstable because of their elevated energy, so minor perturbations would disturb them more. Also, due to their big area, the probability of the atoms interacting with particles is increased, so they will suffer more collisions.

Spotting the tiniest of particles

Current experiments typically look for dark matter particles by trying to detect their scattering off atomic nuclei or electrons on Earth. They do this by looking for light or free electrons in big tanks of liquid noble gases that are generated by energy transfer between the dark matter particle and the atoms of the liquid.

But, according to the laws of quantum mechanics, there needs to be a certain a minimum energy transfer for the light to be produced. An analogy would be a particle colliding with a guitar string: it will produce a note that we can hear, but if the particle is too small the string will not vibrate at all.

So the problem with these methods is that the has to be big enough if we are to detect it in this way. However, our calculations show that the Rydberg atoms will be disturbed in a significant way even by low-mass particles – meaning they can be applied to search for candidates of dark matter that other experiments miss. One of such particles is the Axion, a hypothetical particle which is a strong candidate for dark matter.

Experiments would require for the atoms to be treated with extreme care, but they will not require to be done in a deep underground facility like other experiments, as the Rydberg atoms are expected to be less susceptible to cosmic rays compared to dark matter.

We are working to further improve the sensitivity of the system, aiming to extend the range of particles that it may be able to perceive.

Beyond we are also aiming to one day apply it for the detection of gravitational waves, the ripples in the fabric of space predicted by Einstein long time ago. These perturbations of the space-time continuum have been recently discovered, but we believe that by using atoms we may be able to detect gravitational waves with a different frequency to the ones already observed.

Explore further: Researchers present a new model for what dark matter might be

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24 comments

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Benni
2.6 / 5 (5) Jan 06, 2017
Our model is based on the fact that weakly interacting particles must bounce from the nucleus of the atom it collides with and exchange a small amount of energy with it – similar to the collision between two pool balls.
......but you have yet to come up with a SPECTROSCOPY for that "exchange of energy", this means DM Enthusiasts must continue to INFER this is what ACTUALLY happens when no EVIDENCE in the form of the SPECTROSCOPY exists.

The energy exchange will produce a sudden displacement of the nucleus that will eventually be felt by the electron. This means the entire energy of the atom changes, which can be analysed to obtain information about the properties of the colliding particle.
............OK, if "the entire energy of the atom changes" a Spectrograph of the Spectroscopy can be produced, meanwhile real Spectroscopy continues revealing more & more once unseen VM galaxies in places the MODELS expected to find DM.

dogbert
2.8 / 5 (9) Jan 06, 2017
There seems to be no limit on the amount of time and resources which will be spent trying to find imaginary matter. One would think that after many decades of failure, the money would dry up, but one would be wrong.

Early scientists eventually gave up on the philosopher's stone, but today's scientists are made of sterner stuff.
Benni
2.7 / 5 (7) Jan 06, 2017
We know dark matter exists because of the gravitational pull of galaxy clusters
.......better known as the TinFoil Hat Science of Inferred Gravity.
Osiris1
1.8 / 5 (5) Jan 06, 2017
So we feel the pull of galaxy clusters...astoundingly huge, but the matter scientists can see do not account for the pull. Now how about the matter that is beyond the pale of seeing because it is receding from us faster than the speed of light due to universal expansion function (usually evaluated as a constant perhaps wrongly) times the distance involved. Could it be that the gravitational fields propagate much FASTER than light and we really feel those fields beyond our ability to 'see' them. If we gain an ability to micromeasure these extravisual sources and image them, would they not look like the galaxies in whole or missing part that we cannot see with light?
That would account for the 'missing matter' too!
Now I soooo know the trolls out there would geefle and drag their knuckles at this post.
nikola_milovic_378
2.3 / 5 (3) Jan 07, 2017
Most scientists in this field, means the "anti-human particles" in relation to those of human consciousness which goes towards the spiritual entity of the universe, without which there is no chance to understand the true causes of the events in the universe and in us.
Science, to date, has not learned how arises and disappear and matter and energy, because they do not have any clear picture of the various phenomena and properties of matter and energy.
nikola_milovic_378
2.3 / 5 (3) Jan 07, 2017
Does anyone in the piles of scientists, know what are gravity, electrical charge, magnetism, heat, and how a photon generated and Aton molecules and chemical elements. And these people dare to explain something that is much more complex than these unknowns. Create anything from nothing.
Which is nonsense to examine photon lasers, or talk about a silent atom which they can "get fat" as a farmer or forcibly fed chicken feed.
It is really fun to read these attitudes, because higher that many of these scientists belong to the "color blind scientists."
nikola_milovic_378
2.3 / 5 (3) Jan 07, 2017
All that is for science "dark", a result of ignorance of the existence of the ether and its relationship with aspects of matter and energy.
Let me help you: gravity is unbalanced between the thinner the air, in which matter is "flooded" the very matter that appears in the form of quarks, electrons and positrons. A similar phenomenon of magnetism, or between ether and gluons, which represent the energy (electron-positron annihilation, of which arises gluon).
A photon is a "state of the steam condensate" ether, formed from a sheet of electrons)
For this, there are explanations that correspond to natural laws, and not from PC models and mathematical formulas.
dusty55art
1.7 / 5 (6) Jan 07, 2017
I posted a comment last night but it seems to have disappeared. There never was such a thing as nothing, so creating something from nothing is La La Land. Before the physical universe there was a spiritual universe that contained the laws of Physics. No matter in any form can exist without laws to goven it. There has to be laws of chemistry and nature as well. The laws of physics and the other laws that go with them are spiritual laws and they are eternal. They are simply Truth and the Truth comes out of God. If you are trying to make up a universe without a creator you can spend the rest of your lives arguing and going around in circles. But it still boils down to the DNA of every species (thousands) has to have information to make the cells function and the information has to come from a parent which is God. This information had to be programmed into an infinite sturucture like the Higgs field to produce elementary particles of design.
infinitestructure.com
archytype_net
1.6 / 5 (7) Jan 08, 2017
"
We know dark matter exists because of the gravitational pull of galaxy clusters – the matter we can see in a cluster just isn't enough to hold it together by gravity. So there must be some extra material there, made up by unknown particles that simply aren't visible to us. Several candidate particles have already been proposed."

Perhaps the issue is that the 'forces' they seek to explain with dark matter and dark energy is a nonsense. The force you are searching for to explain how these huge structures are held together is the Electrical forces and magnetic forces present. Hmm?

Hyperfuzzy
1 / 5 (4) Jan 08, 2017
This is like reading a child's fairy tale. No one seems to be concerned with empiricism and logic. There only exists an infinite set of diametrical spherical fields, whose field exists from it's center to infinity, apparently never created or destroyed. The standard model is founded on a false premise. What hold the nucleus together is the solution to N equation with N unknowns, i.e. a neutron is a superposition of the the two diametrical fields. The fields are updated at the speed of light relative to it's center. GR, the SM, BB, String Theory are all nonsense, not based upon any axiomatic structure. Axiom: only DSFs exists. We only see the wrinkles in the field; so exactly how to you make a valid measurement with an invalid theory? The speed of light is not a constant. The wavelength changes very little ion space; therefore, the speed is simply the emitted wavelength divided by the measured period.

Empty space is only conceptual. Proof: The existence of only 1 DSF
Hyperfuzzy
1 / 5 (3) Jan 08, 2017
By the way our universal constants are in error. Dark Matter? WTF!
Da Schneib
4.3 / 5 (6) Jan 09, 2017
It's disappointing that the only comments on this article are from the EU cranks.

This is a suggestion for detecting DM particles using a more rigorous methodology than the liquid noble gas techniques that we have concentrated on so far, and it gives an explanation of why those attempts have failed. I think it should be followed up on.
Hyperfuzzy
2 / 5 (4) Jan 10, 2017
It's disappointing that the only comments on this article are from the EU cranks.

This is a suggestion for detecting DM particles using a more rigorous methodology than the liquid noble gas techniques that we have concentrated on so far, and it gives an explanation of why those attempts have failed. I think it should be followed up on.

The only reason dark matter is even a suggestion is because of flawed science. An attempt to find something that will correct a mistake, 1st do a complete evaluation of belief and logic. i.e. the basic theory. How about a set of undeniable axioms instead of "cra cra."
Scroofinator
2.3 / 5 (3) Jan 10, 2017
This is a suggestion for detecting DM particles using a more rigorous methodology

They can use whatever method of grant fundraising they need, but they won't find anything. DM is gravity misunderstood, not missing.
Zzzzzzzz
3.9 / 5 (7) Jan 10, 2017
Da Sshneib, I was able to add 3 more to the ignore list. New names..... are they really "new?" They sound a lot like some of old, spouting delusional gibberish. When I got done, yours was the only comment left.
Da Schneib
5 / 5 (2) Jan 10, 2017
@Zz, LOL, and yours and mine are the only ones I see, too. We could, I suppose, actually discuss the article. ;)

What do you see this implying for dark matter searches?
Hyperfuzzy
1 / 5 (2) Jan 10, 2017
@Zz, LOL, and yours and mine are the only ones I see, too. We could, I suppose, actually discuss the article. ;)

What do you see this implying for dark matter searches?

How misinformed our scientist are!
Scroofinator
1 / 5 (2) Jan 10, 2017
How misinformed our scientist are!

I wouldn't call them misinformed, but mislead. We have been told since Einstein that ether doesn't exist, yet the the biggest inferometer ever constructed, LIGO, has detected it.
Hyperfuzzy
1 / 5 (1) Jan 11, 2017
How misinformed our scientist are!

I wouldn't call them misinformed, but mislead. We have been told since Einstein that ether doesn't exist, yet the the biggest interferometer ever constructed, LIGO, has detected it.

Maxwell gave us charge, no mass, charge is conserved, its field extends from its center to infinity, updated at the speed of light. Misinformed? Created GR, without measure? Detected ether? Really? Think about it, rather than accepting it. Gluons, without measure. It was as if science did not matter, publish! Even if it makes no sense. OK, call it the system driven by money. Nobel committee, really? Once you see it, it becomes crystal clear. Now I know why glass may be clear. Get it, slow motion. In other words, throw away all books on Particle Physics and GR.
Scroofinator
not rated yet Jan 11, 2017
I really don't know how to take that rant fuzz. I'm with you that particle physics is bogus, but GR is still accurate framework. It just needs adjusted.
Hyperfuzzy
1 / 5 (1) Jan 11, 2017
I really don't know how to take that rant fuzz. I'm with you that particle physics is bogus, but GR is still accurate framework. It just needs adjusted.

No it isn't. The speed of light is simply the emitted wavelength divided by the measured period, i.e. the speed of the wavelet! Anyway the wavelength changes very little in free space. Mass is Not a fundamental property of matter it's an experimental constant, 17th century. Even so, the Mo*d(r/sqrt(1 - (1/c^2)(dr/dt)^2) causes momentum to be a function of displacement! i.e. nonsense! Given mass = Mo(1/sqrt(1-v^2/c^2) ---> nonsense!
Scroofinator
not rated yet Jan 12, 2017
The speed of light is simply the emitted wavelength divided by the measured period

Ok, so what's the emitter?
archytype_net
1.8 / 5 (5) Jan 13, 2017
@Da Schneib

EU cranks! Lol, ha ha ha.....

Just the sort of comment one can expect from the mainstream. You show your mind is closed and that you will not give consideration to any theory or hypothesis if it does not fit in to your preconceived paradigm. That thinking is neither open nor scientific in anticipation way.

I used to think the present 'standard model' was correct etc but having taken the time to actually look in to the alternative ideas and read the papers on the Electric model there is a whole lot more conceptual and theoretical sense in it.
Hyperfuzzy
not rated yet Jan 14, 2017
The speed of light is simply the emitted wavelength divided by the measured period

Ok, so what's the emitter?

Actually a good question. When the charge center moves, the entire spherical field must be updated. So, when the particle moves with repetitive motion, wrinkles in the field are created. So yes, the charge is an infinite object updated at the speed of light relative to its center. So yes no emitter, we use the name "emitter" to represent the object's center.

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