International team of physicists continues search for new physics

January 30, 2019, Purdue University
International team of physicists continues search for new physics
The Compact Muon Solenoid detector is a general-purpose detector at the Large Hadron Collider (LHC) in Switzerland, designed to observe any new physics phenomena that the LHC might reveal. Credit: CERN

Dark matter, which is thought to account for nearly a quarter of matter in the universe (but has yet to be observed), has perplexed physicists for decades. They're constantly looking for something surprising to show up in experiments—results that deviate from the standard model that defines elementary physics.

It's no wonder the was abuzz when an experiment at CERN, known as ATLAS, detected a slight deviation in an experiment in July 2018. Researchers thought they might have finally uncovered evidence of new physics, which could be a sign of . But a recent improvement of the measurement by the CMS collaboration produced results that are nearly consistent with the expectations of the . The findings were published in the January issue of the CERN Courier.

"We wanted to produce a more accurate result than ATLAS had, so we improved the way we reconstruct quantities by using a better correction algorithm, and our results indicate there might not actually have been a deviation there," said Andreas Jung, an assistant professor of physics and astronomy at Purdue University. "This doesn't mean there isn't anything interesting going on here, it just means we don't have the data to prove it right now."

The standard model explains how the basic building blocks of matter interact. It explains , radioactive decays, electrodynamics and more—but not gravity or dark matter. It's the best description of the subatomic world, but it doesn't tell the whole story.

It's what is yet to be included in the standard model, or anything that might contradict it, that physicists are searching for. They primarily use , playfully referred to as "atom smashers" by some, in these experiments.

The Compact Muon Solenoid (CMS) is one of four detectors at the world's largest and most powerful particle accelerator, the Large Hadron Collider. The collider uses to propel charged particles to relativistic speeds and high energies, contains them in beams and sends them smashing into one another. The process remains fairly stable throughout the CMS data-collecting process, but how the information from the detector is analyzed and processed is constantly being tweaked.

"The detector has holes, inefficiencies and missing coverage. All of that has to be accounted for, and the process for that is called data unfolding or data correction," Jung said. "We developed an improvement of this unfolding method that provides a result less sensitive to the input model."

As the methods for interpreting data improve, the collider itself is taking some time off from experiments for renovations. While physicists, engineers and technicians work to make the machine stronger and more efficient, scientists will sift through the incredible amount of untouched data collected thus far. Despite not seeing any strong deviations from the standard model as we know it, Jung remains hopeful.

"Some believe there's a mediator that talks to dark particles. If that's the case, and it couples to the Higgs, we might be able to see it in top quark physics," he said. "We've only looked at a fraction of the data we've collected so far. There could still be something there."

Matthew Jones, an associate professor of physics and astronomy at Purdue, is also a member of the CMS Collaboration, which brings together members of the particle physics community from across the globe in a quest to advance humanity's knowledge of the very basic laws of our Universe. CMS has over 4,000 particle physicists, engineers, computer scientists, technicians and students from around 200 institutes and universities from more than 40 countries.

Explore further: Electrically charged Higgs versus physicists: 1-0 until break

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18 comments

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Bob West
1 / 5 (6) Jan 30, 2019
Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. 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 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 supersolid dark matter is curved spacetime.
Old_C_Code
1.8 / 5 (5) Jan 30, 2019
The center black hole is 4.6 million solar masses.The galaxy of stars orbiting it is almost a trillion solar masses. You'd figure an individual star would orbit per Newton's laws, but how does a group of them with a solar mass much much greater than the center react? Obviously not like Newton's law, as they all cruise around at same speed regardless of radial distance from center. And there is no dark matter effects in elliptical galaxies, only spiral galaxies.
valeriy_polulyakh
2 / 5 (4) Jan 30, 2019
If we believe that our World has started sometimes ago we are still in the position to decide which hypothesis, Lemaître's or Gamow's was closer to reality. There is an opinion that the problems in the standard cosmology could be solved by adjusting of details. Our suggestion is that we have to go back to the conceptions and use the observations accumulated since.
https://www.acade...osmology
https://www.acade...k_Energy
torbjorn_b_g_larsson
3.9 / 5 (7) Jan 30, 2019
And there is no dark matter effects in elliptical galaxies, only spiral galaxies.


Why are you still making these erroneous claims?

First, despite that the article likes the popular science wording, dark matter has been observed in many ways - you even admit to it but only in spiral galaxies for some reason - :

"The primary evidence for dark matter is that calculations show that many galaxies would fly apart instead of rotating, or would not have formed or move as they do, if they did not contain a large amount of unseen matter.[2] Other lines of evidence include observations in gravitational lensing,[3] from the cosmic microwave background, from astronomical observations of the observable universe's current structure, from the formation and evolution of galaxies, from mass location during galactic collisions,[4] and from the motion of galaxies within galaxy clusters....

- tbctd -
torbjorn_b_g_larsson
4.1 / 5 (9) Jan 30, 2019
... In the standard Lambda-CDM model of cosmology, the total mass–energy of the universe contains 5% ordinary matter and energy, 27% dark matter and 68% of an unknown form of energy known as dark energy.[5][6][7][8] Thus, dark matter constitutes 85%[note 2] of total mass, while dark energy plus dark matter constitute 95% of total mass–energy content.[9][10][11][12]"

[ https://en.wikipe...k_matter ]

- tbctd-
torbjorn_b_g_larsson
4.1 / 5 (9) Jan 30, 2019
Second, dark matter is observed in ellipticals, obviously:

"The general conclusion, taking into account all these studies, could be, in summary, that dark matter amounts comparable to visible matter could be present in the visible part of the galaxy, and that larger dark matter amounts, probably as large as in spirals, are present in a halo surrounding the galaxy, but that, in any case, the evidence of dark matter in ellipticals is less than in the case of spirals. Even the complete absence of dark matter cannot be easily ruled out.

Several reviews have been written on the topic (e.g. Ashman, 1992; Trimble, 1987; de Zeeuw, 1992; Kent, 1990; Bertin and Stavielli, 1993). "

[ https://ned.ipac....e11.html ]

-tbctd-
torbjorn_b_g_larsson
4 / 5 (8) Jan 30, 2019
Note that this was 30 years ago! Now we know so much more, LCDM - note dark matter - based simulations produce them:

"... hydrodynamic simulations have begun to produce the right number of galaxies of the right masses and shapes—spiral disks, squat ellipticals, spherical dwarfs, and oddball irregulars ..."

[ https://www.scien...s-cosmic ]

So why can't you keep up with the science, yet think you should opinionate - no references - on side issues that articles do not discuss, and in such an erroneous manner?
arcmetal
2.3 / 5 (6) Jan 30, 2019
Note that this was 30 years ago! Now we know so much more, LCDM - note dark matter - based simulations produce them:

This idea that "we know so much more now ... because of ... computer simulations" is the problem. If you know what answers you want, you can create the computer simulation to produce any outcome you want.

The point is, computer simulations are not observations.
donjoseph
2 / 5 (2) Jan 30, 2019
Excuse me author but Sean Carroll , Brian Greene among others indicate more like 70 to 80 percent dark matter in THE UNIVERSE
Old_C_Code
2.6 / 5 (5) Jan 30, 2019
Second, dark matter is observed in ellipticals, obviously


And your evidence is 25 year old obscure studies? You dopes think you're so smart and the very basis of your studies is flawed, i.e. no observational evidence.
Archi
3 / 5 (4) Jan 31, 2019
"Dark matter, which is thought to account for nearly a quarter of matter in the universe" - I think this statement is not correct. it accounts, however, for 85 % of MATTER in the universe. I think its important here to distinguish the terms matter, energy and energy density.
torbjorn_b_g_larsson
4.3 / 5 (6) Feb 02, 2019
If you know what answers you want, you can create the computer simulation to produce any outcome you want.


Not true, which a reading of the simulation link shows. If you do not care about the subject, why do you make unsupported - even erroneous - claims.

And your evidence is 25 year old obscure studies?


Can't you follow the comments? I put that in to show you that *you* are using older, even more obscure ideas. Then I showed you fresh, and better, results.

So why can't you keep up with the science - or even a comment thread -, yet think you should opinionate?
Whydening Gyre
3.7 / 5 (3) Feb 02, 2019
The center black hole is 4.6 million solar masses.The galaxy of stars orbiting it is almost a trillion solar masses. You'd figure an individual star would orbit per Newton's laws, but how does a group of them with a solar mass much much greater than the center react?

Your missing the fact that gravity is accretive. Each successive "layer" of stars add some to the gravitational affect of what's closer to the center.

savvys84
1 / 5 (2) Feb 05, 2019
hey cern, you want new physics, sky is the limit. chk this out
https://www.scrib...savvys84
Osiris1
not rated yet Feb 05, 2019
Supermassive black holes....no, not your cousin Susie...fall to the center of galaxies that weigh far more, collectively, than most any BH. They fall to the center because that is the centroid of all the mass in the galaxy, and the BH is the most dense and the heaviest cow pie around.
antialias_physorg
4.2 / 5 (5) Feb 05, 2019
Anyone who thinks that scientists are just defending the status quo read this
They're constantly looking for something surprising to show up in experiments—results that deviate from the standard model that defines elementary physics.

Then read it again.
Then read it again.
Then understand it.
Then say you're sorry for wasting everyone's time all these years.
Da Schneib
2.3 / 5 (3) Feb 05, 2019
The most important thought in science is, "Gee, that's funny. I wonder why it did that."
SCVGoodToGo
5 / 5 (2) Feb 05, 2019
@Da Schneib

I prefer the less verbose "Neat."

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