PRISMA+ and HIM scientists report the latest findings of the CASPEr research program in Science Advances.
A team led by Prof Dmitry Budker has continued their search for dark matter within the framework of the “Cosmic Axion Spin Precession Experiment” (or “CASPEr” for short). The CASPEr group conducts their experiments at the PRISMA+ Cluster of Excellence at Johannes Gutenberg University Mainz (JGU) and the Helmholtz Institute Mainz (HIM). CASPEr is an international research program that uses nuclear magnetic resonance techniques to identify and analyze dark matter.
Very little is known about the exact nature of dark matter. Currently, some of the most promising dark matter candidates are extremely light bosonic particles such as axions, axion-like particles, or even dark photons. “These can also be regarded as a classical field oscillating at a certain frequency. But we can’t yet put a figure on this frequency – and therefore the mass of the particles,” explains Dmitry Budker. “That is why in the CASPEr research program we are systematically investigating different frequency ranges looking for hints of dark matter.”
For this, the CASPEr team is developing various special nuclear magnetic resonance (NMR) techniques, each targeted at a specific frequency range and therefore at a specific range of dark-matter particle masses. NMR generally relies on the fact that nuclear spins react to magnetic fields oscillating at a specific “resonance frequency.” The resonance frequency is tuned via a second, usually static magnetic field. The fundamental idea of the CASPEr research program is that a dark matter field can influence the nuclear spins in the same way. As the Earth moves through this field, nuclear spins behave as if they would experience an oscillating magnetic field, thus generating a dark matter induced NMR spectrum.
In the current work, first author Antoine Garcon and his colleagues used a more exotic technique: ZULF (zero- to ultralow-field) NMR. “ZULF NMR provides a regime where nuclear spins interact more strongly with each other than they do with an external magnetic field,” says corresponding author Dr. John W Blanchard. “In order to make the spins sensitive to dark matter, we only have to apply a very small external magnetic field, which is much easier to stabilize.” Furthermore, for the first time, the researchers examined ZULF NMR spectra of 13C-formic acid with respect to dark-matter-induced sidebands, employing a new analysis scheme to coherently average sidebands of arbitrary frequency over multiple measurements.
This particular form of sideband analysis enabled the scientists to search for dark matter in a new frequency range. No dark matter signal was detected, as the CASPEr team reports in the latest edition of Science Advances, allowing the authors to rule out ultralight dark matter with couplings above a particular threshold. At the same time, these results provide another piece of the dark matter puzzle and complement previous results from the CASPEr program reported in June, when the scientists explored even lower frequencies, using another specialized NMR method called “comagnetometry.”
“Like a jigsaw puzzle, we combine various pieces within the CASPEr program to further narrow down the scope of the dark matter search,” asserts Dmitry Budker. John Blanchard adds: “This is just the first step. We are currently implementing several very promising modifications to increase our experiment’s sensitivity.”
Reference: “Constraints on bosonic dark matter from ultralow-field nuclear magnetic resonance” by Antoine Garcon, John W. Blanchard, Gary P. Centers, Nataniel L. Figueroa, Peter W. Graham, Derek F. Jackson Kimball, Surjeet Rajendran, Alexander O. Sushkov, Yevgeny V. Stadnik, Arne Wickenbrock, Teng Wu and Dmitry Budker, 25 October 2019, Science Advances.
DOI: 10.1126/sciadv.aax4539
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7 Comments
gerald itzkowitz
Oct 22, 2019, 5:08 PM (5 days ago)
to Zev
The brane approach is the one I took at least 6 years ago after I read about it in one of the science magazines. Dad
gerald itzkowitz
Oct 22, 2019, 10:11 PM (5 days ago)
to Zev
Note that my approach made use of a talk I heard at NYU in the early 70’s which had some errors which I avoid by my approach. Namely that the crash of a brane into a second one would locally cause a deformation in the second one so that it would not be Euclidean (flat) at the crash site. This would cause matter to come into existence by Relativity laws due to the sink hole depression none Euclidean form. This would then cause the depression to increase causing more matter to form. Note that I believed that this matter would not be ordinary but probably of the form of dark energy.At any rate this process of increasing the local energy would continue indefinitely until the local energy would approach infinity and then there would be a massive explosion known as the big bang of creation. Some of the resultant energy would be the kind of energy we know and would lie in our new 4 dim universe and by Einsteins theory of relativity it would become hydrogen gas. The other energy would become higher dimensional matter lying outside the created 4 dimensional universe that we know though this other mass would affect the motion of future galaxies.in our universe. The higher dimensional mass which scientists have called dark mass or energy would not be detectable in our 4 dimension universe except by how it affects the rotation of each galaxy.
Dark matter is a supersolid that fills ’empty’ space, strongly interacts with ordinary matter and is displaced by ordinary matter.
The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.
Displaced dark matter is curved spacetime. More correctly, what is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.
The supersolid dark matter displaced by the quarks the Earth consists of, pushing back and exerting pressure toward the Earth, is gravity.
“Dark matter is a supersolid which is displaced by ordinary matter” is the physics version of saying “the Earth is flat.” Grow up and learn some proper CERN-related physics about axions.
So, if dark mater is displaced by normal mater, then our solar system has had 4.5 Billion years to displace all the dark mater away from us. This might be wny we haven’t detected any. There simply is no dark mater here. It has all been displaced away. Maybe a collection of various detectors could be put in a space probe, and sent out of the solar system perpendicular to the ecliptic. When the space probe gets far enough away, maybe it would have a chance of seeing a dark mater signal. Then again, the space probe is made of normal mater, and could it’s self displace the dark mater away from it’s self. If dark mater is displaced by normal mater we may not have any way of detecting it.
I like the concept of a ‘supersolid’ in the discussion of gravitational forces, but I still contend that dark matter displacement is actually the insulation between the dark energy medium, that is our space-time template [i.e. pre-existing matter], and ordinary matter. Indeed ordinary matter and dark matter are part and parcel of the existence of the whole matter as created from within the medium of dark energy. For without contentious relationship of dark matter to dark energy, there would be no ordinary matter. Dark energy represents the force responsible for the effect of universal inflation and Dark Matter represents the force responsible for the effect of universal gravitation. Dark Matter fills the empty space within and about ordinary matter, as the complementary force of displacement created by the introduction of the whole matter within the medium of dark energy. Upon the creation of matter, these three participants take upon their innate forces in relationship to each other.
Thinking of gravity as the force involved in the paired creation of matter, as a whole, it then follows that this complementary dark matter is representative of the gravitational force that binds ordinary matter. Consequently, dark matter is what engenders the force of gravity through the displacement, or warping, of space-time. Subsequently when this complementary relationship is severed, ordinary matter is disintegrated and discarded out back into the cosmos, leaving dark matter to remain as a displacement in space-time. This is what happens when matter, as a whole, is separated upon the event horizon of a black hole.
Whereupon the black hole is not infinitely dense, but rather it is a degree of negative mass density. The greater the negative mass density, the greater the space-time displacement (or warping). Currently there is no known calculation as to what degree of negative mass density displacement is considered to much or too little. The greater the space-time warp, the deeper the gravity well and the greater the force of gravitational acceleration. So black holes can be very small or really chock-full of dark matter. The smaller it is the greater the chance it can reacquire its relationship with ordinary matter.
It is a relationship that intertwines itself even unto the smallest constituents of mass to accrete and form much larger molecular bodies, like planets. So, as it turns out, the gravitational force of a planet is also based on its negative mass density, where the greatest accumulation is situated at its gravitational center.
If you want to understand black hole, dark matter, and dark energy better, read ‘Evolutioning of Creation: Volume 2’, and such possible interaction as portrayed in the sci-fi novel, ‘Shadow-Forge Revelations’.
Instead of continuing to chase imaginary pixie dust based on a theory that can never be scientifically disproven, perhaps energy, attention, and funds should be directed to alternative theories that don’t require invisible supernatural entities.
Why couldn’t dark mater be what’s inside of black holes? There are a lot of really big black holes.