Smashing time with ALICE.
A picture shows the tracks of particles produced in a lead ion smashup in the Large Hadron Collider.
A picture shows the tracks of particles produced in a lead ion smashup in the Large Hadron Collider.
Image: ALICE/CERN
Like all good scientists, cosmologists are re-examining what they thought they knew and, because there are new facts, they are allowing these facts to dictate their understanding. The issue is when exactly the matter in the Universe was created by natural forces.
But before creationists start celebrating, these cosmologists would laugh at the childish notion that it was all made by magic 10,000 years ago. In fact, the revision is over whether it was all produced in the first few picoseconds after the Big Bang, or 0.000001 seconds later. There is no doubt about whether the Big Bang happened or how long ago it happened and it was many orders of magnitude longer ago than Creationists like to imagine.
The problem is that in the immediate aftermath (and we are talking of picoseconds) the Universe was far too hot (some 250,000 times hotter than the sun's core) for even elementary particles to form in the high-energy electromagnetic field in which quarks couldn't even interact.
Tell me all about the first few nanoseconds after the Big Bang and how matter coalesced from it. The first few nanoseconds (1 nanosecond = 10-9 seconds) after the Big Bang represent an incredibly complex and dynamic period in the evolution of the universe. During this time, the universe transitioned through several critical phases, leading to the formation of matter as we know it. Here's an overview of what happened:Now two cosmologists, Joseph Dominicus Lap from Department of Physics, Yale University, New Haven, CT, USA and Berndt Müller, from Department of Physics, Duke University, Durham, NC, USA, have applied a new calculation and shown that 70% of particles were created later than previously thought. These new calculations come from recreating the conditions in the early universe by smashing together lead (Pb) atoms travelling at near light speed. By measuring the shower of elementary particles this creates, scientists are able to calculate back to the earliest moments of the Universe.
First Few Nanoseconds after the Big Bang
Planck Epoch (up to 10-43 seconds)
- Time Frame: From 0 to approximately 10-43 seconds.
- Description: All fundamental forces were unified. The universe was at the Planck temperature (~1032 Kelvin).
Grand Unification Epoch (10-43 to 10-36 seconds)
- Time Frame: From 10-43 to 10-36 seconds.
- Description: Gravity separated from the unified fundamental force. The temperature was still extremely high.
Inflationary Epoch (10-36 to 10-32 seconds)
- Time Frame: From 10-36 to 10-32 seconds.
- Description: The universe underwent rapid exponential expansion. Quantum fluctuations during this period laid the foundation for the universe's large-scale structure.
Electroweak Epoch (10-36 to 10-12 seconds)
- Time Frame: From 10-36 to 10-12 seconds.
- Description: The strong force separated from the electroweak force, which later split into the electromagnetic and weak nuclear forces. Particles such as quarks and leptons formed.
- Conditions: The temperature was around 1015 Kelvin by the end of this epoch.
Quark Epoch (10-12 to 10-6 seconds)
- Time Frame: From 10-12 to 10-6 seconds.
- Description: The universe was filled with a hot, dense plasma of quarks, gluons, and leptons. Quarks began to bind together to form hadrons (protons and neutrons) as the universe cooled.
- Conditions: The temperature dropped to around 1012 Kelvin by the end of this epoch.
Hadron Epoch (10-6 seconds to 1 second)
- Time Frame: From 10-6 seconds to 1 second.
- Description: Quarks combined to form hadrons, such as protons and neutrons. Most antimatter annihilated with matter, leaving a slight excess of matter.
- Conditions: The temperature continued to decrease, reaching about 1010 Kelvin by the end of this epoch.
Glossary of Particles
- Quark: Fundamental particles that combine to form protons and neutrons. There are six types (flavors): up, down, charm, strange, top, and bottom.
- Lepton: A family of fundamental particles that includes electrons, muons, tau particles, and neutrinos. Leptons do not experience the strong nuclear force.
- Gluon: The exchange particles (bosons) responsible for the strong nuclear force that binds quarks together inside hadrons.
- Proton: A hadron composed of two up quarks and one down quark, carrying a positive electric charge.
- Neutron: A hadron composed of two down quarks and one up quark, electrically neutral.
- Photon: The quantum of electromagnetic radiation, acting as the force carrier for the electromagnetic force.
- Neutrino: A very light, neutral lepton that interacts only via the weak nuclear force and gravity.
- Hadron: Composite particles made of quarks held together by the strong force. Protons and neutrons are the most stable hadrons.
- Antimatter: Particles that are counterparts to regular matter particles, with opposite charges. For example, the positron is the antimatter counterpart to the electron.
Key Processes
- Baryogenesis: The hypothetical process that produced an imbalance between matter and antimatter in the early universe.
- Cosmic Inflation: A rapid expansion of the universe by a factor of at least 1026 in a tiny fraction of a second.
- Recombination: The process by which electrons combined with protons and other nuclei to form neutral atoms, allowing photons to travel freely through space and leading to the Cosmic Microwave Background radiation.
These stages and processes illustrate the intricate development of the early universe, leading from a hot, dense state to the formation of matter as we observe it today.
The cosmologists' highly technical paper was published in Physics Letters B last November, and is explained in Phys.Org News from information supplied by the US Department of Energy.
Discovery sheds light on the origins of matter in the early universeAs I said, the open access paper is highly technical and way above my paygrade as a humble biologist, but here it is if any creationists want to lie about it or try to discredit it in some way:
The early universe was 250,000 times hotter than the core of our sun. That's far too hot to form the protons and neutrons that make up everyday matter. Scientists recreate the conditions of the early universe in particle accelerators by smashing atoms together at nearly the speed of light.
Measuring the resulting shower of particles allows scientists to understand how matter formed. The particles that scientists measure can form in various ways: from the original soup of quarks and gluons or from later reactions.
These later reactions began 0.000001 seconds after the Big Bang, when the composite particles made of quarks began to interact with each other.
A new calculation determined that as much as 70% of some measured particles are from these later reactions, not from reactions similar to those of the early universe. The research is published in the journal Physics Letters B.
This finding improves scientific understanding of the origins of matter. It helps identify how much of the matter around us formed in the first few fractions of a second after the Big Bang, versus how much matter formed from later reactions as the universe expanded.
This result implies large amounts of the matter around us formed later than expected. To understand the results of collider experiments, scientists must discount the particles formed in the later reactions.
Only those formed in the subatomic soup reveal the early conditions of the universe. This new calculation shows that the number of measured particles formed in reactions is much higher than expected.
In the 1990s, physicists realized that certain particles form in significant numbers from the later reactions following the initial formation phase of the universe. Particles called D mesons can interact to form a rare particle, charmonium.
Scientists lacked consensus on how important the effect is. Since charmonium is rare, it is difficult to measure. However, recent experiments provide data on how many charmonium and D mesons colliders produce.
Physicists from Yale University and Duke University used the new data to calculate the strength of this effect. It turns out to be much more significant than expected. More than 70% of charmonium measured could be formed in reactions.
As the hot soup of subatomic particles cools, it expands in a ball of fire. This all happens in less than one hundredth of the time it takes for light to cross an atom. Since this is so fast, scientists are unsure exactly how the fireball expands.
The new calculation shows that scientists do not absolutely need to know the details of this expansion. The collisions produce a significant amount of charmonium regardless. The new result brings scientists one step closer to understanding the origins of matter.
AbstractWell, I said it was technical, but it gets even more technical later on.
We make use of published yields for D-mesons and \({J/\psi}\) in Pb+Pb collisions at ALICE and a schematic description of the expansion of the hadron gas to study D-meson collisions during the hadronic break-up phase as a production mechanism for charmonium in relativistic heavy ion collisions at the Large Hadron Collider. Our calculation is based on chemical reaction rates with thermal cross sections for an effective meson interaction among pseudoscalar and vector mesons. We find that due to regeneration, the newly measured \({J/\psi}\) yields are consistent with anywhere from roughly 25% to 110% of the total yield present at hadronization time. This allows us to bound the fractional abundance of \({J/\psi}\) immediately after hadronization: \(0.28 \leq \frac{\frac{dN_0^{J/\psi}}{dy}}{\frac{dN_{eq}^{J/\psi}}{dy}} \leq 1.13\). Our results are robust under the relaxation of the particulars of our schematic description and imply that it will be difficult to distinguish regeneration during hadronization from regeneration by final-state hadronic interactions. Therefore, regeneration must be taken into account when modeling.
Lap, Joseph Dominicus & Müller, Berndt
Hadronic \({J/\psi}\) regeneration in Pb+Pb collisions Physics Letters B (2023) 846 138246; DOI: 10.1016/j.physletb.2023.138246
Copyright: © 2023 The authors.
Published by Elsevier B.V., Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
So, all creationists need do now is explain why the evidence and the maths fail to support them and why we should go with their evidence-free superstition for no better reason than that their mummy and daddy believed it, and they were brainwashed into being too morbidly theophobic the even question them.
If you aren't bothered about the truth, it's easier to claim to know the answer to all questions, regardless of whether it’s the right answer or not, so long as you have an answer, then, from a position of ignorance, you can pretend to be more expert than the experts.
But what creationists don't seem to be able to grasp is the reason that the experts don't agree with them after they've learned the facts and understood the subject. Why is there this yawning chasm between what scientist say the facts show and what creationists think the facts should show?
Why do they imagine that learning things leads you to the wrong answer whilst remaining ignorant guarantees you have the right answer?
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