IWARA2026 - 12th International Workshop on Astronomy and Relativistic Astrophysics

Aug 31, 2026, 8:45 AM → Sep 4, 2026, 6:00 PM America/Mexico_City

Auditorio José Adem, Mexico

J Alberto Vazquez, Peter Hess, Tonatiuh Matos

The event will be exclusively in person.

Our understanding of the origin of the Universe, of its evolution and the physical laws that govern its behavior, as well as on the different states of matter that makes up its evolutionary stage, reached in recent years levels never before imagined. This is due mainly to the new and recent discoveries in astronomy and relativistic astrophysics as well as to experiments on particle and nuclear physics that made the traditional boundaries of knowledge on physics to be overcome. As a result we have presently a new understanding about the Universe in its two extreme domains, the very large and the very small: the recognition of the deep connections that exist between quarks and the cosmos.

The intimate relationship between quarks and cosmos has motivated the organization of the series of international events known by the acronym IWARA – International Workshop on Astronomy and Relativistic Astrophysics.

The event is the 12th in a series of meetings gathering scientists working on astroparticle physics, cosmology, gravitation, nuclear physics, and related fields. As in previous years, the IWARA 2026 meeting sessions will consist of exclusively in person invited and contributed talks, poster sessions, and will cover recent developments in the following topics:

• New phenomena and new states of matter in the Universe
• General relativity, gravitation, cosmology
• New directions for general relativity: past, present and future of general relativity
• FRW cosmologies
• Cosmic microwave background radiation
• First Stars, hypernovae, and faint supernovae in the early Universe
• Quantum gravity and quantum cosmology
• Gravity and the unification of fundamental interactions
• Supersymmetry and Inflation
• String theory
• White dwarfs, neutron stars and pulsars
• Black hole physics and astrophysics
• Gamma-ray emission in the Universe
• High energy cosmic rays
• Gravitational waves
• Dark energy and dark matter
• Strange matter and strange stars
• Antimatter in the Universe
• High-energy cosmic neutrinos
• Blazars
• Quantum chromodynamics, nuclear and particle physics and new states of matter in the Universe.
• Heavy ion collisions and the formation of the quark-gluon plasma in heavy ion collisions and in the first instants of the Universe
• Strong magnetic fields in the Universe, strong magnetic fields in compact stars and in galaxies, ultra-strong magnetic fields in neutron star mergers, quark stars and magnetars, strong magnetic fields and the cosmic microwave background
• Laboratories, observatories, telescopes and other experimental and observational facilities that will define the future directions of astrophysics, astronomy, cosmology, nuclear and astroparticle physics as well as the future of physics at the energy frontiers, and topics related to these.

 

The event will be organized by Universidad Nacional Autónoma de México (UNAM).

During the IWARA2026 event, the Sandoval Vallarta Prize will be awarded to the top five student contributions of the poster session. 

Some important dates. 

June 30: Last day to register an abstract
July 31: Last day to pay the reduced registration fee
August 31: Last day to pay the registration fee
Workshop: August 31 to September 4

 

 

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Poster_IWARA.jpeg

anouncements

• CODE OF CONDUCT IOP.pdf
• First-Announcement_IWARA2026.pdf
• Safety in Mexico City.pdf
• Second-Announcemente_IWARA2026.pdf
• Time Table.pdf

Poster IWARA 2026_20251106_154704_0000_251112_120516.pdf Poster_IWARA.jpeg

Mon, August 31

8:45 AM → 9:00 AM Opening

9:00 AM → 9:30 AM The 500 m Precision Floor in Neutron Star Radius Measurements

abstract. Multi-messenger observations of neutron stars aim to constrain the dense-matter equation of state via mass-radius measurements. We demonstrate that, for a canonical 1.4 M⊙ star, current crust-modeling uncertainties impose a persistent∼500 m precision floor in radius predictions. This threshold is comparable to—and in some cases exceeds—the radius differences predicted for quark-hadron transitions, hyperonic cores, dark matter admixture, and modified gravity. Consequently, in the one-dimensional mass-radius plane, these scenarios remain effectively degenerate. Breaking this degeneracy requires either reducing crustal uncertainties to σR ≪500 m—a challenge for current missions—or shifting toward multi-observable tomography. The 500 m precision floor thus reframes the inverse problem, motivating a move beyond radius measurements alone.

Speaker: CESAR AUGUSTO Zen Vasconcellos (UFRGS/ICRANet)

9:30 AM → 10:20 AM M Alcubierre

10:20 AM → 11:10 AM F S Guzmán

11:10 AM → 11:30 AM Coffee break

11:30 AM → 11:50 AM VPOS from multistate Scalar Field Dark Matter

Observations have confirmed that satellite galaxies of the Milky Way, as well as those of Andromeda and Centaurus A, exhibit a non-homogeneous distribution known as the Vast Polar Structure (VPOS), where satellites show orbits aligned perpendicular to the host galaxy's plane. Conventional Cold Dark Matter (CDM) models face significant challenges in explaining this anisotropic distribution across multiple galaxies. In this work, we propose that the quantum nature of the Scalar Field Dark Matter (SFDM) model offers a natural explanation for the VPOS. By incorporating finite temperature corrections for a complex, self-interacting scalar field at early cosmological epochs, we demonstrate that the SFDM halo behaves as a macroscopic gravitational atom. We show that the system's quantum character allows for the formation of ground and excited states, specifically, p-states that resemble lobes along the north-south direction, which can explain the observed VPOS. By fitting these multistate SFDM solutions to rotation curves for the Milky Way, Andromeda, Centaurus A, and additional galaxies, we find that this model effectively accounts for the anisotropic distribution of satellite galaxies, suggesting that this structure may be a general characteristic of galaxies in the Universe.

Speaker: Tula Bernal (Universidad Autónoma Chapingo)

11:50 AM → 12:10 PM M Hernández

12:10 PM → 12:30 PM L Sánchez

12:30 PM → 1:20 PM Lam Hui

1:20 PM → 3:00 PM Lunch

3:00 PM → 3:50 PM A González

3:50 PM → 4:20 PM Constructing de Sitter space and Dark Matter with Dynamical Tension Strings

The string tensions can be dynamical in the modified measure formalism and appear as an additional dynamical degrees of freedom . These tensions may not be universal, instead, each string generates its own tension. We then consider a new bulk field that can couple to the strings, the tension scalar which changes locally the tension along the world sheet. In the case with two string tensions there is a braneworld solution which gives rise to an induced de Sitter space in the brane, avoiding swampland constraints of the standard string theory. Strings with different tension to ours can appear also as Dark Matter and since they share the same space and compactifications as visible matter, they should lead to Dark copies of the standard model,

Speaker: Eduardo Leon Guendelman (Ben Gurion University)

4:20 PM → 4:40 PM L Bixano

4:40 PM → 5:00 PM Gravitational Waves from Mergers of Asymmetric Dark Stars

A strongly self-interacting component of asymmetric dark matter (DM) particles can form compact dark stars (DSs). These objects have a broad spectrum of masses and radii, with distinct evolution histories from both neutron stars and black holes (BHs). We argue that these differences allow a population of DSs to contribute significantly to the astrophysical merger rate in unique and discernible ways. Specifically, their merger rate could dominate at low redshifts over other sources, while their mass function may populate windows outside known astrophysical processes. We investigate the structure and formation of DSs within a dissipative model, and calculate the enhancement of their merger cross-section due to tidal deformation effects. From this, we derive the cosmological DS merger rate and discuss the DM parameter space available for observation. These findings open a new window to probe DM substructure and particle interactions through present and future gravitational wave (GW) observatories.

Speaker: Boris Betancourt Kamenetskaia (Institute for Basic Science CTPU-CGA)

5:00 PM → 5:20 PM Coffee break

5:20 PM → 5:40 PM S Mendoza

5:40 PM → 6:00 PM A León

Tue, September 1

9:00 AM → 9:30 AM S Mendoza

9:30 AM → 10:20 AM L Ureña

10:20 AM → 11:10 AM J Cervantes

11:10 AM → 11:30 AM Coffee break

11:30 AM → 11:50 AM M G Aspeitia

11:50 AM → 12:10 PM Deformed phase-space for a non-singular cosmology

We present the implications of incorporating noncommutativity into f(R) gravity. In particular, we explore the proposed framework in a flat FRLW background. We introduced a deformation in a 2n-dimensional phase space.

Speaker: Dr ERI ATAHUALPA MENA BARBOZA (Centro Universitario de la Ciénega, Universidad de Guadalajara)

12:10 PM → 12:30 PM Reparametrization Invariance and the Phenomena of Dark Energy & Dark Matter

The nature of dark energy (DE) challenges our comprehension of the cosmos, appearing as the source responsible for the Universe’s accelerating expansion. This work considers the Einstein Cosmological Constant (ΛE) as a manifestation of DE, interpreted through the lens of Reparametrization Invariant Scaling Symmetry (RISS). Within this paradigm, ΛE emerges as a “kinetic energy” term, derived from relative temporal motion, setting it apart from the conventional kinetic energy based on spatial relative motion.

Central to this exploration is the scale factor λ(t) representing a reparametrization capable of rendering ΛE dynamically within the extended equations of Einstein’s General Relativity(EGR) as Λ=ΛE*λ^2. Through meticulous derivations, the governing equations of λ(t) and its interplay with ΛE are articulated. Imposing reparametrization symmetry on the equations of motion reveals a new avenue for addressing the missing mass problem evident at galactic and extragalactic scales. Here, improper/non-affine (non co-moving) temporal parameterizations introduce fictitious forces, whose presence is reconciled through the symmetry framework.

This symmetry-based approach naturally yields the MOND-like relationship, g^2 ∼ (a0gN), where g denotes gravitational acceleration, a0 represents the fundamental MOND acceleration, and gN is the Newtonian acceleration. The theoretical predictions for ΛE and a0 demonstrate remarkable alignment with their observed magnitudes, lending credence to this interpretation. This synthesis underscores a potential unifying principle in our understanding of dark energy and dark matter phenomena.

Speaker: Dr Vesselin Gueorguiev (NCIS, RIIS 2.0, and IAPS)

12:30 PM → 1:20 PM Cesar Zen

1:20 PM → 3:00 PM Lunch