Results 41 to 50 of about 738 (163)

Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the String‐Theoretical Swampland Programme

Fortschritte der Physik, Volume 74, Issue 4, April 2026.
Abstract String theory has strong implications for cosmology, implying the absence of a cosmological constant, ruling out single‐field slow‐roll inflation, and that black holes decay. The origins of these statements are elucidated within the string‐theoretical swampland programme.
Kay Lehnert
wiley   +1 more source

Feature importance for machine learning redshifts applied to SDSS galaxies

, 2015
Accepted —-. Received —-; in original form —-. We present an analysis of importance feature selection applied to photometric redshift estimation using the machine learning architecture Random Decision Forests (RDF) with the ensemble learning routine ...
Markus Michael Rau, Roman Zitlau, Rau, M., Stella Seitz, Jochen Weller, Ben Hoyle, Hoyle, B., Weller, J., Zitlau, R., Seitz, S.   +9 more
core   +1 more source

Unified Analysis of Fermionic Tunneling, Barrow‐Exponential Entropy Corrections, and Plasma Lensing in Carrollian Reissner‐Nordström Spacetime

Annalen der Physik, Volume 538, Issue 3, March 2026.
Carrollian Reissner‐Nordström black holes are investigated through fermionic tunneling, entropy‐corrected thermodynamics, and plasma‐modified gravitational lensing. The generalized uncertainty principle introduces minimal‐length corrections to the Hawking temperature, while the combined Barrow‐Exponential entropy reveals smooth thermodynamic crossovers
Erdem Sucu, İzzet Sakallı, Yusuf Sucu
wiley   +1 more source

Can Cosmological Simulations Reproduce the Spectroscopically Confirmed Galaxies Seen at $z\geq 10$?

, 2023
Recent photometric detections of extreme $(z>10)$ redshift galaxies from the JWST have been shown to be in strong tension with existing simulation models for galaxy formation, and in the most acute case, in tension with $\Lambda CDM$ itself.
M. Tremmel, Trebitsch, M., B. W. Keller, Munshi, F., Tremmel, M., Keller, B. W., F. Munshi, M. Trebitsch   +7 more
core   +1 more source

A New Padé Approach to Modeling Wormholes in Dekel‐Zhao Dark Matter Halos

Annalen der Physik, Volume 538, Issue 3, March 2026.
A matter‐first Padé strategy is introduced to build traversable wormholes from prescribed dark‐matter halos. Rational Padé fits approximately the Dekel–Zhao density and are analytically integrated to obtain a shape function that exactly reproduces the intended matter content, avoiding spurious poles of geometry‐first schemes.
Jonathan Alves Rebouças, Francisco Tiago Barboza Sampaio, Francisco Bento Lustosa, Leonardo Tavares de Oliveira, C. R. Muniz   +4 more
wiley   +1 more source

Clustering and redshift-space distortions in QSO and galaxy surveys [PDF]

, 2006
In this thesis, we exploit the potential of existing QSO and galaxy surveys for investigating the nature of the large scale structure in the Universe. A detailed analysis of clustering and redshift- space distortions allows us to constrain cosmological ...
Cruz da Angela, José Antonio, José Antonio Cruz da Angela   +1 more
core  

Logarithmic and Strong Coupling Models in Weyl‐Type f(Q,T)$f(Q,T)$ Gravity

Annalen der Physik, Volume 538, Issue 1, January 2026.
This work explores Weyl‐type f(Q,T) gravity using recent observational datasets — CC, Pantheon+, Union 3.0, and DESI DR2. Through MCMC analysis of logarithmic and strong coupling models, the study reveals a transition from deceleration to acceleration, quintessence‐to‐phantom dynamics, and late‐time consistency with LCDM, offering a geometry‐driven ...
Rahul Bhagat, S. K. Tripathy, B. Mishra
wiley   +1 more source

Adsorption of Helium on Cationic or Anionic Tetracene and Pentacene

Small Structures, Volume 7, Issue 1, January 2026.
How does the arrangement of helium atoms that are adsorbed on tetracene or pentacene ions change with increasing coverage? When does the adsorption layer change from 1D to 2D, and to 3D? Is the transition abrupt? Are the helium atoms localized? Is the arrangement the same for cations and anions? What changes as the acene grows in length?
Miriam Kappe, Florent Calvo, Rasif William, Bilal Rasul, Masoomeh Mahmoodi‐Darian, Paul Scheier, Olof Echt   +6 more
wiley   +1 more source

Two Micron‐Size Dark Dimensions

Fortschritte der Physik, Volume 73, Issue 8, August 2025.
Abstract Two extra dimensions of micron scale might simultaneously address the gauge and cosmological hierarchy problems. In this paper various observational bounds in scenarios with one and two large extra dimensions are examined, to see if they are compatible with the micron scale.
Luis A. Anchordoqui, Ignatios Antoniadis, Dieter Lüst   +2 more
wiley   +1 more source

Low-resolution VLT spectroscopy of GRBs 991216, 011211 and 021211 [PDF]

, 2006
Gamma rays: bursts, galaxies:, abundances, galaxies: distances and redshifts, galaxies: quasars: absorption ...
Watson, D., PALAZZI, E, Fruchter, A. S., Rol, E., Wijers, R.A.M.J., Vreeswijk, P. M., C. Kouveliotou (7590188), L. Kaper, KOUVELIOTOU, C, P. T. O'Brien, N. Masetti (7612289), L. Piro (7620851), P. Jakobsson (7590599), VREESWIJK, P. M, Fruchter, S., L. Kaper (7603490), J. P. U, JAKOBSSON, D. Watson, F, HJORTH, PIAN, E, Fynbo, J.P.U., E. Palazzi (7603466), P. T. O'Brien (7604567), A. Smette, L, FYNBO, P, WATSON, Fruchter, A.S., J. Hjorth (2463328), D. Watson (6553337), Jakobsson, P., O'Brien, P.T., Ledoux, C., ROL, E, FRUCHTER, A. S, F. Frontera, C. Ledoux (7613075), Hjorth, J., Frontera, F., P. T, LEDOUX, A. S. Fruchter, P. M. Vreeswijk (7601714), J, PIRO, D, O'BRIEN, N. Masetti, C. Kouveliotou, A. S. Fruchter (7590185), Kouveliotou, C., R. A. M. J. Wijers (7590200), A. Smette (7620935), E. Pian, MASETTI, N, C., E. Rol, E. Pian (7612277), J. Gorosabel (7603436), P. M. Vreeswijk, WIJERS, R. A. M. J, J, GOROSABEL, L. Piro, FRONTERA, Filippo, E. Palazzi, J. Hjorth, J. P. U. Fynbo (7603457), SMETTE, A, Palazzi, E., J. P. U. Fynbo, Masetti, N., P. Jakobsson, Smette, A., Piro, L., C. Ledoux, R. A. M. J. Wijers, Kaper, L., Gorosabel, J., KAPER, L, F. Frontera (7581629), J. Gorosabel, Pian, E., Vreeswijk, P.M., E. Rol (7601738), Fynbo, J., O'Brian, P. T.   +81 more
core   +1 more source