Question Condensates

Page 7 - Seeking answers about space? Join the Space community: the premier source of space exploration, innovation, and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier.
Hello Adoni
You are right Gravity is directly related to mass.

Hurricanes spin is controlled by external difference in pressures.

The core of a Blackhole has a spin property is internal forces that unites all the core.
The Chiral Super Symmetry creates Dipolar Electromagnetic fields that eject droplets of condensates. These droplets can be 10^18 to 10^30 plus compaction. A droplet of this matter can seed stars.
The jets created can explain the spiral arms of Spiral Galaxies.

This is why I'm encouraging you to keep doing what you are doing and at the same time research Transient Phase Condensates, it may take you some time.
 
The scientists that keep at it, trying to understand, are given full credit, I take my hat off for doing so.

[Submitted on 22 Jan 2024]

The earliest phase of relativistic heavy-ion collisions​

Margaret E. Carrington, Stanislaw Mrowczynski
According to the Color Glass Condensate approach to relativistic heavy-ion collisions, the earliest phase of the collision is a glasma which is made of highly populated gluon fields that can be treated classically. Using a proper time expansion we study analytically various properties of the glasma. In particular, we compute the glasma energy-momentum tensor which allows us to obtain the energy density, longitudinal and transverse pressure, collective flow, and angular momentum. We also study the role of the glasma in jet quenching by computing collisional energy loss and transverse momentum broadening.
 
Jun 11, 2023
181
9
85
Visit site
Hello Adoni
You are right Gravity is directly related to mass.

Hurricanes spin is controlled by external difference in pressures.

The core of a Blackhole has a spin property is internal forces that unites all the core.
The Chiral Super Symmetry creates Dipolar Electromagnetic fields that eject droplets of condensates. These droplets can be 10^18 to 10^30 plus compaction. A droplet of this matter can seed stars.
The jets created can explain the spiral arms of Spiral Galaxies.

This is why I'm encouraging you to keep doing what you are doing and at the same time research Transient Phase Condensates, it may take you some time.
Thanks for the comments, Harry!! But what I argue is that gravity is directly related to mass and the rate at which the matter particles of the mass heat up!!

I argue that unless matter particles heat up by net imploding GP1 Aether Particles that matter CANNOT GENERATE gravitational force/ low GP1 Aether Particle Pressure!!
And that the proof is given by the history of our Sun which is given as heating up from a hydrogen-helium molecular cloud at 10 degrees Kelvin for the past 5 billion years to 5850 Kelvin in our Sun's photosphere, now.

I argue that when our Sun stops heating up in 5 billion years and starts to cool that the stored potential dark energy in our Sun comes out transforming our Sun to a Red Giant!!

My concepts are novel and original and go against people’s ordinary views!!

You may say to yourself that I see that the Earth generates gravitational force but I don’t see our planet heating up except by green house emissions so what in the universe is Adoni talking about??

Consider that the Earth’s mass and each of its individual particles is given to be a “perpetual” gravitational force energy machine forever and ever and ever!!

To understand): Just ask yourself is the Earth’s mass given to generate gravitational force in direct proportion to its mass forever and ever and ever?? and is perpetual energy possible?? The answer should be a resounding no!!

The fact that our Sun’s rays heat up air particles at the Equator that create low air pressure systems that strengthen to hurricanes from warm water and sunlight and weaken over cooler land will not convince you, right now, that EM waves heating air atoms up result in low GP1 Aether Particle Pressure systems that result in low air pressure systems but give it time reread my old posts at your leisure and, one day, you will be among the few to know the exact physical mechanical processes that generate gravity while storing potential dark energy!! And Much Much More!!

Talk more, soon!! Have a great day!!
 
Last edited:
Jun 11, 2023
181
9
85
Visit site
The scientists that keep at it, trying to understand, are given full credit, I take my hat off for doing so.
According to the Color Glass Condensate approach to relativistic heavy-ion collisions, the earliest phase of the collision is a glasma which is made of highly populated gluon fields that can be treated classically. Using a proper time expansion we study analytically various properties of the glasma. In particular, we compute the glasma energy-momentum tensor which allows us to obtain the energy density, longitudinal and transverse pressure, collective flow, and angular momentum. We also study the role of the glasma in jet quenching by computing collisional energy loss and transverse momentum broadening.
[Submitted on 22 Jan 2024]

The earliest phase of relativistic heavy-ion collisions​

Margaret E. Carrington, Stanislaw Mrowczynski
Your Reference’s Abstract Says): “According to the Color Glass Condensate approach to relativistic heavy-ion collisions, the earliest phase of the collision is a glasma which is made of highly populated gluon fields that can be treated classically.”

Very interesting that the authors define glasma as a highly populated gluon fields that can be treated classically.

So, I believe that from relativistic heavy-ion collisions researchers observe something for an instant that they consider to be highly populated gluon fields which the researchers named “glasma”!!

But like other of your posts on condensates, there is, absolutely, no connection but conjecture with what happens with relativistic heavy-ion collisions and what happens on the large scale like with neutron star compact objects!!

Let’s try to limit this post's discussion to the question): Is the “singularity” or mass inside black holes just 3 or more solar masses of the neutronium of neutron star material at 200 trillion or more times Earth density?? Or, Just, a larger neutron ball of neutronium?? Which I suggest is composed of embryonic neutron permeable sacs that when warmed up to Absolute Zero decay through Beta Decay Minus to atomic hydrogen and observed in the 21 centimeter wavelength throughout the cosmos at 1.42 GHz that translates to a temperature of 0.0681 Kelvin so very very close to absolute zero??

Anyway, do you see why atomic hydrogen which results, right, after neutron beta decay minus is observed to be so close to absolute zero at 0.0682 Kelvin and far far below the given 2.75 Kelvin temperature of the Cosmic Microwave Background Radiation (CMBR)??

Talk more, soon!! Have a great day!!
 
Last edited:
Hello Atlan thank you for the paper.

Scientists will continue to keep researching quantum mechanics.


"This exciting discovery is part of ongoing research by Csathy's team. The team continues to push the limits of discovery in their persistent pursuit of topological electron physics."
 
This may interest some of you.

[Submitted on 12 Mar 2024]

Spatially oscillating correlation functions in (2+1)-dimensional four-fermion models: The mixing of scalar and vector modes at finite density​

Marc Winstel
In this work, we demonstrate that the mixing of scalar and vector condensates produces spatially oscillating, but exponentially damped correlation functions in fermionic theories at finite density and temperature. We find a regime exhibiting this oscillatory behavior in a Gross-Neveu-type model that also features vector interactions within the mean-field approximation. The existence of this regime aligns with expectations based on symmetry arguments, that are also applicable to QCD at finite baryon density. We compute the phase diagram including both homogeneous phases and regions with spatially oscillating, exponentially damped correlation functions at finite temperature and chemical potential for different strengths of the vector coupling. Furthermore, we find that inhomogeneous condensates are disfavored compared to homogeneous ones akin to previous findings without vector interactions. We show that our results are valid for a broad class of (2+1)-dimensional models with local four-fermion interactions.
 
I would advise people to research condensates and their Transient phases.


[Submitted on 29 Feb 2024]

Quantum droplets with magnetic vortices in spinor dipolar Bose-Einstein condensates​

Shaoxiong Li, Hiroki Saito
Motivated by the recent experimental realization of a Bose-Einstein condensate (BEC) of europium atoms, we investigate the self-bound droplet state of a europium BEC with spin degrees of freedom. Under a sufficiently weak magnetic field, the droplet has a torus shape with circulating spin vectors, which is referred to as a magnetic vortex. The ground state transforms from the torus to cigar shape through bistability with an increase in the magnetic field. Dynamical change of the magnetic field causes the torus to rotate due to the Einstein-de Haas effect. The magnetic vortices form a supersolid in a confined system.
 
The research in this field is very important in explaining Star formation and galaxy formation. Jets formed within stars and from Black hole mainly large ones found in the center of a galaxy, although Black Hole do exist throughout the Galaxy.

[Submitted on 18 Sep 2007]

A search for Very High Energy gamma-ray emission from Passive Super-massive Black Holes​

G. Pedaletti, S. Wagner, W. Benbow (for the HESS collaboration)
Jets of Active Galactic Nuclei (AGN) are established emitters of very high energy (VHE; >100 GeV) gamma-rays. VHE radiation is also expected to be emitted from the vicinity of super-massive black holes (SMBH), irrespective of their activity state. Accreting SMBH rotate and generate a dipolar magnetic field. In the magnetosphere of the spinning black hole, acceleration of particles can take place in the field gaps. VHE emission from these particles is feasible via leptonic or hadronic processes. Therefore quiescent systems, where the lack of a strong photon field allows the VHE emission to escape, are candidates for emission. The H.E.S.S. experiment has observed the passive SMBH in the nearby galaxy NGC 1399. No VHE gamma-ray signal is observed from the galactic nucleus. Constraints set by the NGC 1399 observations are discussed in the context of different mechanisms for the production of VHE gamma-ray emission.

and

[Submitted on 5 Feb 2020]

Plasmoid formation in global GRMHD simulations and AGN flares​

Antonios Nathanail, Christian M. Fromm, Oliver Porth, Hector Olivares, Ziri Younsi, Yosuke Mizuno, Luciano Rezzolla
One of the main dissipation processes acting on all scales in relativistic jets is thought to be governed by magnetic reconnection. Such dissipation processes have been studied in idealized environments, such as reconnection layers, which evolve in merging islands and lead to the production of plasmoids, ultimately resulting in efficient particle acceleration. In accretion flows onto black holes, reconnection layers can be developed and destroyed rapidly during the turbulent evolution of the flow. We present a series of two-dimensional general-relativistic magnetohydrodynamic simulations of tori accreting onto rotating black holes focusing our attention on the formation and evolution of current sheets. Initially, the tori are endowed with a poloidal magnetic field having a multi-loop structure along the radial direction and with an alternating polarity. During reconnection processes, plasmoids and plasmoid chains are developed leading to a flaring activity and hence to a variable electromagnetic luminosity. We describe the methods developed to track automatically the plasmoids that are generated and ejected during the simulation, contrasting the behaviour of multi-loop initial data with that encountered in typical simulations of accreting black holes having initial dipolar field composed of one loop only. Finally, we discuss the implications that our results have on the variability to be expected in accreting supermassive black holes.
 
So! Scientist are forging onwards, step by step to find the properties of condensates and how they mimic Black Hole Properties.

[Submitted on 25 Apr 2024]

Deci-Hz gravitational waves from the self-interacting axion cloud around the rotating stellar mass black hole​

Hidetoshi Omiya, Takuya Takahashi, Takahiro Tanaka, Hirotaka Yoshino
Gravitational waves from condensates of ultra-light particles, such as axion, around rotating black holes are a promising probe to search for unknown physics. For this purpose, we need to characterize the signal to detect the gravitational waves, which requires tracking the evolution of the condensates, including various effects. The axion self-interaction causes the non-linear coupling between the superradiant modes, resulting in complicated branching of evolution. Most studies so far have considered evolution under the non-relativistic approximation or the two-mode approximation. In this paper, we numerically investigate the evolution of the axion condensate without these approximations, taking higher multipole modes into account. We also investigate the possible signature in gravitational waves from the condensate. We show that the higher multipole modes are excited, leading to the gravitational wave signal by the transition of the axion between different levels. The most prominent signal of gravitational waves arises from the transition between modes with their angular quantum numbers different by two. The gravitational wave signal is emitted in the deci-Hz band for stellar mass black holes, which might be observable with the future gravitational wave detectors.
 
Phase Transitions is one of the most important types of research in the field from compact atomic to Neutron matter to Quark matter to partonic matter to Axion matter and Neutrino Matter.
This subject is so interesting, I can't wait to see how far we can go in 5 to 10 years.

[Submitted on 25 Apr 2024]

Identifying the ground state phases by spin-patterns in the Shastry-Sutherland model​

Yun-Tong Yang, Fu-Zhou Chen, Hong-Gang Luo
Exploring the influence of frustration on the phases and related phase transitions in condensed matter physics is of fundamental importance in uncovering the role played by frustration. In the two-dimensional square lattice, a minimal frustration has been formulated in 1981 as the Shastry-Sutherland (SS) model described by competitions between the nearest-neighbor bond (J1) and the next-nearest-neighbor one (J2). In the two limits of α=J2/J1, i.e. α≪1 and α≫1, the corresponding phases are the N{é}el antiferromagnet (AFM) and the dimer-singlet(DS). Unfortunately, the intermediate regime remains controversial, and the nature of transition from the N{é}el AFM to the intermediate state is also unclear. Here we provide a pattern language to explore the SS model and take the lattice size L=4×4 with periodic boundary condition. We firstly diagonalize the Hamiltonian in an operator space to obtain all fundamental spin-patterns and then analyze their energy and occupancy evolutions with the frustration parameter κ=α/(1+α). Our results indicate that the intermediate regime is characterized by diagonal two-domain spin-pattern while the N{é}el AFM state has a diagonal single-domain and the DS has mixings of diagonal single- and four-domain. While the transition from the DS to the intermediate phase occurred around αc=1.5 is the first-order in nature, consistent with that in literature, the one from the intermediate phase to the AFM is clearly seen around αc=1.277, where it has a reversal of the contributions from the single- and two-domain patterns to the ground state. The result indicates that the pattern language is powerful in identifying the possible phases in frustrated models.
 
Compact objects to mimic black holes.

[Submitted on 23 Feb 2024 (v1), last revised 11 Mar 2024 (this version, v2)]

Workshop on the limiting compactness objects: Black holes and Buchdahl stars​

Dawood Kothawala, Sahil Saini
The workshop was organized at IUCAA on Oct 30 - Nov 3, 2023 as a compact discussion and discourse meeting with a threadbare exposition and discussion of the various aspects and the questions arising. It was occasioned by the visit of Professor Hakan Andreasson of the Gothenburg Technical University, Sweden. He has been exploring with his collaborators the Einstein - Vlasov system for over a decade and a half as a possible matter source for compact objects. This system characterizes itself by free particles in motion and interacting only through gravity. For a limiting compactness, this may be the most appropriate state. The main thrust of the workshop was to understand this new object, Buchdahl Star (BS), of limiting compactness without a horizon. It is almost as compact as a black hole (BH) and yet has no horizon and hence is open for interaction with the outside world. Ever since the proposal of the membrane paradigm envisaging a timelike fiducial surface near BH horizon, BS offers an excellent possibility of the existence of such a real astrophysical object. It could very well compete with BH as a mimicker for various physical and astrophysical phenomena. Thus, it opens up a new vista of study and investigation of all the questions that one asks for BH, for this new creature, BS. The workshop was intended to identify certain interesting questions as well as the people interested in studying them. On this count, the workshop has been a huge success as several interesting questions have been identified, a few groups have been formed to take up different problems, and the work has already started. Nothing more could one have asked from such an exercise. A brief summary of some of the talks is included, followed by a brief discussion of the projects identified as a result of the discussions during the workshop.
 
It's always good to extend your research into the unknown.
Relevant to Condensates.

[Submitted on 20 Jun 2024]

Black holes with electroweak hair​

Romain Gervalle, Mikhail S. Volkov
We construct static and axially symmetric magnetically charged hairy black holes in the gravity-coupled Weinberg-Salam theory. Large black holes merge with the Reissner-Nordström (RN) family, while the small ones are extremal and support a hair in the form of a ring-shaped electroweak condensate carrying superconducting W-currents and up to 22% of the total magnetic charge. The extremal solutions are asymptotically RN with a mass {\it below} the total charge, M<|Q|, due to the negative Zeeman energy of the condensate interacting with the black hole magnetic field. Therefore, they cannot decay into RN black holes. As their charge increases, they show a phase transition when the horizon symmetry changes from spherical to oblate. At this point they have the mass typical for planetary size black holes of which ≈11% are stored in the hair. Being obtained within a well-tested theory, our solutions are expected to be physically relevant.
 
The properties of condensates are properly the most important research in explaining the formation of stars, galaxies supernova formation such as the hourglass, Dipolar vortices etc.

[Submitted on 21 Jun 2024]

To explain the muon excess phenomenon in cosmic rays based on the gluon condensation model​

Bingyang Liu, Zhixiang Yang, Jianhong Ruan
Ultrahigh-energy cosmic rays are often characterized indirectly by analyzing the properties of secondary cosmic ray particles produced in the collisions with air nuclei, the particle number Nμ of muon and the depth of shower maximum Xmax after air shower cascade are mostly studied to infer the energy and mass of the incident cosmic rays. While, researches have shown that there is a significant excess comparing the observed number of muons arriving at the ground from extensive air showers (EAS) with the simulations by using the existing cosmic ray hadronic interaction model. To explain this muon excess phenomenon, a new theoretical model, the gluon condensation model (GC model), is introduced in this paper and simulated by using the AIRES engine. We asumme that the GC effect appearing mainly in the first colliding of the cascade, leads to a significant increase in the strangeness production, accodingly, the production rate of kaons is improved appearantly. The model assumes that only pions and kaons are the new prodcutions in the hadron cascades. It is found that, considering the GC effect, the value of nK/nπ increases and more energy of the incident cosmic rays paticipate in hadron cascades, and then increase the number of mouns finally. This model provides a new theoretical possibility to explain the muon excess puzzle.
 
The vortices that are formed from Condensates (BH) are very important in the formation of stars.

[Submitted on 30 Jun 2024]

The evolution and detection of vector superradiant instabilities​

Yin-Da Guo, Nayun Jia, Shou-Shan Bao, Hong Zhang, Xin Zhang
Ultralight vectors can extract energy and angular momentum from a Kerr black hole (BH) due to superradiant instability, resulting in the formation of a BH-condensate system. In this work, we carefully investigate the evolution of this system numerically with multiple superradiant modes. Simple formulas are obtained to estimate important timescales, maximum masses of different modes, as well as the BH mass and spin at various times. Due to the coexistence of modes with small frequency differences, the BH-condensate system emits gravitational waves with a unique beat signature, which could be directly observed by current and projected interferometers. Besides, the current BH spin-mass data from the binary BH merger events already excludes the vector mass in the range 5×10−15 eV<μ<9×10−12 eV.
 
Condensates properties allow us to think outside the square.
Transient Condensates may allow us to understand Condensates that have the properties of Black Holes without a singularity. The dipolar property prevents a singularity from forming.

[Submitted on 7 May 2024 (v1), last revised 8 May 2024 (this version, v2)]

Ground-state properties of dipolar Bose-Einstein condensates with spin-orbit coupling and quantum fluctuations​

Xianghua Su, Wenting Dai, Tianyu Li, Jiyuan Wang, Linghua Wen
We study the ground-state properties of dipolar spin-1/2 Bose-Einstein condensates with quantum fluctuations and Rashba spin-orbit coupling (SOC). The combined effects of dipole-dipole interaction (DDI), SOC, and Lee-Huang-Yang (LHY) correction induced by quantum fluctuations on the ground-state structures and spin textures of the system are analyzed and discussed. For the nonrotating case and fixed nonlinear interspecies contact interaction strengths, our results show that structural phase transitions can be achieved by adjusting the strengths of the DDI and LHY correction. In the absence of SOC, a ground-state phase diagram is given with respect to the DDI strength and the LHY correction strength. We find that the system exhibits rich quantum phases including square droplet lattice phase, annular phase, loop-island structure, stripe-droplet coexistence phase, toroidal stripe phase, and Thomas-Fermi (TF) phase. For the rotating case, the increase of DDI strength can lead to a quantum phase transition from superfluid phase to supersolid phase. In the presence of SOC, the quantum droplets display obvious stretching and hidden vortex-antivortex clusters are formed in each component. In particular, weak or moderate SOC favors the formation of droplets while for strong SOC the ground state of the system develops into a stripe phase with hidden vortex-antivortex clusters. Furthermore, the system sustains exotic spin textures and topological excitations, such as composite skyrmion-antiskyrmion-meron-antimeron cluster, meron-antimeron string cluster, antimeron-meron-antimeron chain cluster, and peculiar skyrmion-antiskyrmion-meron-antimeron necklace with a meron-antimeron necklace embedded inside and a central spin Neel domain wall.
 
How jets form is extremely important
M87 has stable dipolar jets that are over 100,000 light yrs.
What is the force that allows such a stubbily.
Are we getting closer to understanding.
Slowly yes
The answer lies within the condensate core. It's worth looking at transients of condensates.

[Submitted on 11 Jun 2024]

Jet quenching in the glasma phase: medium-induced radiation​

João Barata, Sigtryggur Hauksson, Xoán Mayo López, Andrey V. Sadofyev
Inspired by the recent considerations of parton momentum broadening in the glasma phase, we study the medium-induced soft gluon radiation of jet partons at early times in heavy-ion collisions. The glasma state is assumed to be comprised of independent color domains with homogenous longitudinal fields that vary event by event, and we further complete this model with an event-averaging procedure accounting for the finite correlation length. Using this description, we evaluate the rate of medium-induced radiation from an energetic parton at midrapidity in the glasma phase. We mainly focus on SU(2) color fields for simplicity, also referring to the U(1) case and comparing with the BDMPS-Z rate to gain further insight. Our results show that there is an intricate interplay of the synchrotron-like radiation in a single color domain with the destructive interference between different color domains, after the medium averaging is performed. Thus, we find that the emission rate is sensitive to the matter structure, decreasing for a glasma state populated by smaller color domains, i.e. for a glasma with a larger characteristic saturation scale. Our approach can be applied to more realistic backgrounds, and sets the stage for the modelling of jet evolution in the early stages of heavy-ion collisions.
 
To explain the jets formed from stars and AGN and black holes. One needs to understand the properties of condensates.


[Submitted on 6 Aug 2024]

Jet definition and TMD factorisation in SIDIS​

Paul Caucal, Edmond Iancu, A. H. Mueller, Feng Yuan
Using the colour dipole picture of Deep Inelastic Scattering (DIS) and the Colour Glass Condensate effective theory, we study semi-inclusive jet production in DIS at small x in the limit where the photon virtuality Q2 is much larger than the transverse momentum squared P2⊥ of the produced jet. In this limit, the cross-section is dominated by aligned jet configurations, that is, quark-antiquark pairs in which one of the fermions -- the would-be struck quark in the Breit frame -- carries most of the longitudinal momentum of the virtual photon. We show that physically meaningful jet definitions in DIS are such that the effective axis of the jet sourced by the struck quark is controlled by its virtuality rather than by its transverse momentum. For such jet definitions, we show that the next-to-leading order (NLO) cross-section admits factorisation in terms of the (sea) quark transverse momentum dependent (TMD) distribution, which in turn satisfies a universal DGLAP and Sudakov evolution.
 
They are approaching this by looking at near Horizon condense.
They could be right.
But! I feel that more focus should be on the core of the Black Hole Condensate.
The core can generate dipolar fields that can remain stable for thousands of years eg, M87 jets.

[Submitted on 21 Aug 2024]

Supergravity Spectrum of AdS5 Black Holes​

Nizar Ezroura, Finn Larsen
We embed Kerr-Newman-AdS black holes into N=8 gauged supergravity and study quadratic fluctuations around the black hole backgrounds of all fields in the larger theory. The equations of motion of the perturbations are partially diagonalized by the group theory of broken symmetry. Nearly all fields in theory have non-minimal couplings, so their equations of motion are not merely massive Klein-Gordon equations with minimal coupling to background gauge fields, and their analogues for fields with spin. In the special case of extremal black holes we identify specific modes of instability, some of which touch supersymmetric locus. For example, we identify scalar fields in supergravity that condense in the near horizon region and transition the black hole into a superconducting phase. We also identify supergravity modes that are susceptible to superradiant instability.
 
Harry, how long after Mankind opens the Space Frontier do you think it will be until Mankind farming SPACE's solar and/or cosmic energies via Star Wars and Star Trek Enterprise-like condensation to matter materials processor processes, quantum information qubits (materials DNA), and artificial to natural life (dealing with organics and possible starfish-like growths and re-growths), to produce what fuels, fusions, plasmas, gases, liquids and solids, individually and in-mass for whatever is required, needed and wanted at some particular time?

Essentially making alchemist chemistry a reality.
 
Last edited:
Hello Atla
You said: Essentially making alchemist chemistry a reality.

I never thought that way.
Maybe so

To control a condensate is a very dangerous activity.

Making weapons of extreme mass distraction.
Advance spacefaring life is probably extremely spread out, always accelerating in its expansion to and into frontier, a diluted infinity lost in all the countless other varying infinities. Weapons of extreme mass destruction count only in densely packed, naturally or artificially, tyrannically boxed in closed world systems. There, only, weapons and wielders of such will have the reach for extreme mass destruction. Life spreads out as far and as wide, and in as large numbers and variations, as it can to survive mass destructions / mass extinctions.
 
Last edited:
Condensed Transient phases are not a new subject. But! one that needs to be investigated. The answer to many images that we observe lies in understanding this subject.

[Submitted on 29 May 2024]

Exact results, transient generalized Gibbs ensembles, and analytic approximations for spacetime propagators of massive, real scalar fields in one spatial dimension​

Tobias Boorman, Bernd Braunecker
The massive, real scalar field described by the Klein-Gordon equation in one spatial dimension is the most elementary example of a bosonic quantum field theory, and has been investigated for many decades either as a simple academic theory or as a realistic emergent many-body theory in low-dimensional systems. Despite this, the space and time behavior of its propagators have rarely been in the foreground, and although exact results are known, there remain gaps in the description and a lack of an in-depth physical analysis. The aim of this paper is to address the deficits by providing a comprehensive discussion of the results, and to show that this old theory still allows for several new results and insights. To start, known results are rederived in full detail, with an added discussion on how exactly space and time variables need to be extended to complex values to ensure analyticity throughout spacetime. This procedure shows also how singularities on the lightcone need to be regularized to remain compatible with the analyticity and the physical limit of a vanishing mass. An extension to nonzero temperatures is provided by considering the contact of the field to a nonrelativistic thermal reservoir, such as is necessary for emerging field theories in condensed matter systems. Subsequently, it is shown that the transient, short spacetime propagation can be understood in the context of the modern development of a generalized Gibbs ensemble, which describes a massless theory with an effective temperature that is set by the Klein-Gordon mass and the physical temperature. Finally, an approximation scheme is presented that captures the non-trivial mass dependence of the propagators throughout all spacetime but involves only elementary functions.