Tag

Cosmological Horizon

All articles tagged with #cosmological horizon

Cosmic Acceleration May Be a Signature of Quantum Gravity on the Horizon
science2 hours ago

Cosmic Acceleration May Be a Signature of Quantum Gravity on the Horizon

Physicist Savvas Koushiappas suggests the Universe’s accelerating expansion could arise from a quantum modification to cosmic geometry at the cosmological horizon, meaning dark energy might be replaced by a macroscopic imprint of quantum gravity. By tying the uncertainty in simultaneously knowing the Universe’s size and expansion rate to altered expansion equations, the model could explain acceleration and even allow a bouncing origin instead of a Big Bang, though it leaves several questions unresolved. Future data from DESI, Euclid, and the Vera Rubin Observatory could test these ideas and refine our understanding of cosmic expansion.

Cosmic Acceleration Could Be a Quantum Gravity Imprint, Not Dark Energy
science4 hours ago

Cosmic Acceleration Could Be a Quantum Gravity Imprint, Not Dark Energy

A new Physical Review D paper by Savvas Koushiappas suggests the Universe’s accelerating expansion may arise from a macroscopic quantum uncertainty in simultaneously knowing the Universe’s size and expansion rate, effectively tying cosmic acceleration to quantum gravity at the cosmological horizon rather than to dark energy. The model can modify the expansion history and even allow a Big Bang replacement by a bounce in some configurations. Observations from DESI, Euclid, and the Vera C. Rubin Observatory could test these ideas, but the proposal remains speculative with open questions about consistency and interpretation.

James Webb Telescope Unveils Ancient Light Sources Shaping the Universe
science-and-space2 years ago

James Webb Telescope Unveils Ancient Light Sources Shaping the Universe

The James Webb Space Telescope (JWST) has observed the galaxy JADES-GS-z14-0, located 33.8 billion light-years away, challenging our understanding of the universe's age and expansion. Despite the universe being 13.8 billion years old, the expansion of space allows us to see such distant objects. This phenomenon is explained by the universe's accelerating expansion due to dark energy, making it possible for JWST to observe galaxies that were once causally connected to Earth but are now moving away faster than the speed of light.