Arthur T Knackerbracket has found the following story:
New findings from University of Kansas experimental nuclear physicists Daniel Tapia Takaki and Aleksandr (Sasha) Bylinkin were just published in the European Physical Journal C. The paper centers on work at the Compact Muon Solenoid, an experiment at the Large Hadron Collider, to better understand the behavior of gluons.
Gluons are elementary particles that are responsible for "gluing" together quarks and anti-quarks to form protons and neutrons—so, gluons play a role in about 98% of all the visible matter in the universe. Previous experiments at the now-decommissioned HERA electron-proton collider found when protons are accelerated close to light-speed, the density of gluons inside them increases very rapidly.
"In these cases, gluons split into pairs of gluons with lower energies, and such gluons split themselves subsequently, and so forth," said Tapia Takaki, KU associate professor of physics & astronomy. "At some point, the splitting of gluons inside the proton reaches a limit at which the multiplication of gluons ceases to increase. Such a state is known as the 'color glass condensate,' a hypothesized phase of matter that is thought to exist in very high-energy protons and as well as in heavy nuclei."
The KU researcher said his team's more recent experimental results at the Relativistic Heavy Ion Collider and LHC seemed to confirm the existence of such a gluon-dominated state. The exact conditions and the precise energy needed to observe "gluon saturation" in the proton or in heavy nuclei are not yet known, he said.
"The CMS experimental results are very exciting, giving new information about the gluon dynamics in the proton," said Victor Goncalves, professor of physics at Federal University of Pelotas in Brazil, who was working at KU under a Brazil-U.S. Professorship given jointly by the Sociedade Brasileira de Física and the American Physical Society. "The data tell us what the energy and dipole sizes are needed to get deeper into the gluonic-dominated regime where nonlinear QCD effects become dominant."
Although experiments at the LHC don't directly study interaction of the proton with elementary particles such as those of the late HERA collider, it's possible to use an alternative method to study gluon saturation. When accelerated protons (or ions) miss each other, photon interactions occur with the proton (or the ion). These near misses are called ultra-peripheral collisions (UPCs) as the photon interactions mostly occur when the colliding particles are significantly separated from each other.
[...] The researchers said the work is significant because it's the first establishment of four measured points in terms of the energy of the photon-proton interaction and as a function of the momentum transfer.
"Previous experiments at HERA only had one single point in energy," Tapia Takaki said. "For our recent result, the lowest point in energy is about 35 GeV and the highest one is about 180 GeV. This does not sound like a very high energy point, considering that for recent J/psi and Upsilon measurements from UPCs at the LHC we have studied processes up to the 1000s GeV. The key point here is that although the energy is much lower in our Rho0 studies, the dipole size is very large."
(Score: 2) by bzipitidoo on Wednesday September 11 2019, @05:29PM (13 children)
Relativity is weird stuff. How can a particle's gluons differ just because it's traveling near light speed relative to a lot of other, nearby mass? From its point of view, why don't gluons multiply in all that other matter? I can only suppose it's acceleration itself that's providing the energy for this weird gluon multiplication effect.
I would guess it does make sense, it's just our bad terminology that's making things difficult to comprehend. Why is it not possible (so far as we know) to travel faster than light? Faster than light travel certainly need not violate causality, fun though it is to think about time travel paradoxes. Another one is temperature scales and absolute zero. Gets people to wondering if it's possible to go colder than absolute zero. Why can't we have -10 Kelvin, or -100 Kelvin? But if you put temperature in terms of motion, and absolute zero is absolute stillness, then, yeah, it doesn't make sense to have even more stillness than total stillness.
(Score: 2) by DannyB on Wednesday September 11 2019, @06:00PM (6 children)
Similarly with absolute darkness. It doesn't make sense to have even more dark than total dark. Or total absence of light. But like absolute zero temperature, can you ever really quite get there? Speaking of dark, a total absence of photons?
From TFA . . .
Maybe it only appears to us, from our frame of reference that gluon density increases very rapidly. Maybe those accelerated protons see our gluon density decreasing very rapidly?
Ah! In the same town with this local headline that could have been better written . . .
Suicides on the rise locally; Lawrence summit will offer tools to help [ljworld.com]
The lower I set my standards the more accomplishments I have.
(Score: 3, Touché) by hendrikboom on Wednesday September 11 2019, @06:06PM (4 children)
Not clear to me whether the increased gluon presence is during acceleration or after it, i.e., when velocity is near light-speed. If it's the latter, we'll be near light-speed in the proton's reference frame. so the protons would see *our* protons has having extra gluons as well.
(Score: 2) by DannyB on Wednesday September 11 2019, @06:15PM (3 children)
Good point. Sorry no mod points left for a Touche. Just like how contraction (foreshortening) of length works both ways.
<sarcasm>but since we are "at rest", our protons should have extra gluons as seen from the protons moving near light speed</sarcasm>
Based on my layman's understanding, an electron "orbiting" a nucleus, is not really at any single physical location. It is really at all points around the nucleus at the same time, just with higher probabilities of being at certain locations. ("everyman's guide to science") Maybe our thinking of and describing of gluons as particles limits our thinking. Is there a way gluons could have higher density without having an increased "count"? Not that I would know.
The lower I set my standards the more accomplishments I have.
(Score: 2) by hendrikboom on Wednesday September 11 2019, @08:59PM
I supposed they could be a mixed state whose eigenstates have different counts. Those eigenstates would of course be the eigenstates of the "count 'em" operator.
(Score: 2) by Snotnose on Wednesday September 11 2019, @09:06PM (1 child)
It's even weirder. The electron can not only be inside the nucleus itself, it can be inside the protons and neutrons.
When the dust settled America realized it was saved by a porn star.
(Score: 2) by DannyB on Wednesday September 11 2019, @09:23PM
I did notice that the electron could be inside the proton.
Of course, it's just the probability that the electron is there.
The lower I set my standards the more accomplishments I have.
(Score: 2) by c0lo on Wednesday September 11 2019, @10:32PM
Nope, even if, paradoxically, you can reach in the territory of negative absolute temperatures (all lasers are operating in this mode).
The highest temperature theoretically possible is minus-zero-absolute; as for the case of positive zero temperatures, you approach it asymptotically.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 4, Interesting) by hendrikboom on Wednesday September 11 2019, @06:02PM
Temperature is the derivative of energy with respect to entropy. So if you have a physical system in which there is a maximum possible particle energy (and there are quantum-mechanical systems with this property), when the energy gets close to the maximum there is the same paucity of available states as when normal systems come close to their minimum energy. The result is that the derivative of energy with respect to entropy becomes negative (add more energy and the entropy decreases), and thus you have a negative absolute temperature.
Absolute zero is still a barrier temperature. The route from positive temperature to negative takes the long detour via infinity rather than cross the zero point. It's as if the significant physical property is the reciprocal of temperature, rather than the temperature.
-- hendrik
(Score: -1, Redundant) by Anonymous Coward on Wednesday September 11 2019, @06:20PM
The heavy nuclei bit is a clue.
There is a mismatch in our terminology, but I wouldn't call it "bad." It just doesn't describe the physics very intuitively, but it does describe our everyday experiences more intuitively than tensors do.
(Score: 2) by Barenflimski on Wednesday September 11 2019, @08:30PM (1 child)
This is how I think of all of this. To me it seems to make sense in terms of a wave.
If a Gluon is accelerated, the potential energy rises, so therefore the gluon-wave/particle will resonate at a higher frequency, thereby allowing it to split into smaller "gluons." I simply have trouble imagining that there is a sticky particle. I can imagine a wave of energy that is say negatively charged that holds together two positively charged gluons. Again, this is simply my laymans terms for this as I have no idea about the actual charges, this is more of a metaphor for me at this point. Does that make sense?
Maybe someone can help me out and tell me which version of Physics this falls into. I enjoy the Copenhagen view of Physics. I find Pilot wave theory interesting. I don't believe that there are separate particles and waves though. It seems to me that they are one in the same and that particles are the physical manifestation of waves. It seems to me that the particles condensate (for lack of a better word) out of the wave.
Can someone help me out... is that view the same as the Copenhagen view? Is there another view out there that I've missed being an armchair physicist?
(Score: 3, Interesting) by hendrikboom on Wednesday September 11 2019, @09:12PM
I like the so-called multiple universes interpretation, because that's a direct interpretation of the mathematics. Though I like to call it relative state theory, because I like to emphasize that the state of any system is relative to the observer.
And if you assume that there's essentially one observer (who is the totality of classical physical reality) it specializes down to the Copenhagen interpetation.
As for particles versus waves, I have to go to my own armchair physics. When you observe something, you hit it with a measurement operator, and the something jumps into a state that is one of the eigenstates of the operator that you are measuring with. And (here comes the armchair) presumably if your operator is one whose eigenstates are particles, you get particles.
-- hendrik
(Score: -1, Redundant) by Anonymous Coward on Wednesday September 11 2019, @09:10PM
The temperature is an illusion all the way down. It is actually a phenomenon of speed, a movement. Zero means, there is no movement. Absolutely negative temperature would mean a negative speed, movement in negative space, which has no physical interpretation currently.
(Score: 0) by Anonymous Coward on Thursday September 12 2019, @06:00AM
You know, instead of spending 20 minutes writing a shitpost about not understanding anything, go and spend 20 minutes understanding it.
Not saying I am up with teh gluons but you can get "in the ballpark" with electrons and protons. Physics *must* be the same from every reference frame.
Start here: https://www.youtube.com/watch?v=1FE0Z4lov7Y [youtube.com]
(Score: 4, Funny) by DeathMonkey on Wednesday September 11 2019, @05:32PM (2 children)
Near misses? You had one job, collider!
(Score: 0) by Anonymous Coward on Wednesday September 11 2019, @05:39PM (1 child)
Can we just put someone's hand in the collider again?
(Score: 3, Informative) by SunTzuWarmaster on Wednesday September 11 2019, @06:58PM
(Score: 2) by SunTzuWarmaster on Wednesday September 11 2019, @06:55PM
(Score: 0) by Anonymous Coward on Wednesday September 11 2019, @09:24PM
>the density of gluons inside them increases very rapidly
So is this the cause of relativistic mass increase?
(Score: 2) by hendrikboom on Wednesday September 11 2019, @10:00PM
I wonder if there's any relationship to Unruh radiation, which is radiation you see while you are being accelerated. likely not, but ...
(Score: 2) by hendrikboom on Thursday September 12 2019, @01:19AM (2 children)
The summary left out one of he more interesting lines in the original paper.
If this is what it seems to be (perhaps a big IF) this is intriguing. There has been speculation for a while that the quantum mechanics we know is but a linear low-energy approximation to another, more comprehensive, nonlinear high-energy physics. If that's true, we need the nonlinearity to truly understand black holes, big bangs, and the like.
I've seem the blackboard-sized equations for the Lagrangian of all physics taken together, and wondered, isn't there something simpler that this can be derived from? Maybe by differentiation or maximization or some such?
I've been given hope when someone took the Lagrangian for general relativity (the one that gives rise to Einstein's field equation) and introduced one more source of variability -- that the gravitational constant G, the speed of light, and one other number (I forget what) might not be in constancy with respect to one another, but they can vary. This gave one other thing to vary into the minimization math, and out came the Einsteinian field equations with a cosmological constant, with a specific value, and that value matched observed astronomical results.
So this is a case where something was gained from a more general framework. Could the same happen with a nonlinear quantum mechanics?
- hendrik
(Score: 1, Funny) by Anonymous Coward on Thursday September 12 2019, @03:57AM (1 child)
If you differentiate 42 then... it gets complicated. Don't do that.
(Score: 2) by hendrikboom on Tuesday September 17 2019, @04:19PM
Too simple.
Things should be as simple as possible, but no simpler.