Using a chain of atoms in single-file to simulate the event horizon of a black hole, a team of physicists has observed the equivalent of what we call Hawking radiation – particles born from disturbances in the quantum fluctuations caused by the black hole’s break in spacetime.
This, they say, could help resolve the tension between two currently irreconcilable frameworks for describing the Universe: the general theory of relativity, which describes the behavior of gravity as a continuous field known as spacetime; and quantum mechanics, which describes the behavior of discrete particles using the mathematics of probability.
For a unified theory of quantum gravity that can be applied universally, these two immiscible theories need to find a way to somehow get along.
The cosmic optical background (COB) is the visible light emitted by all sources outside of the Milky Way. This faint glow of light, which can only be observed using very precise and sophisticated telescopes, could help astrophysics to learn more about the origins of the universe and what lies beyond our galaxy.
Last year, physicists working at different institutes across the United States published the most precise COB measurements collected so far, gathered by the New Horizons spacecraft, an interplanetary space probe launched by NASA over a decade ago. These measurements suggested that the COB is two times brighter than theoretical predictions.
Researchers at Johns Hopkins University have recently carried out a theoretical study exploring the possibility that this observed excess light could be caused by the decay of a hypothesized type of dark matter particles, known as axions. In their paper, published in Physical Review Letters, they showed that axions with masses between 8 and 20 eV could potentially account for the excess COB flux measured by the New Horizons team.
The most jaw-dropping pictures of space this year.
From the Pillars of Creation to the Milky Way’s black hole, 2022 has been full of incredible photos from space. Here are the best space pictures of 2022.
How could we one day travel between the stars with real physics? Perhaps the greatest challenge to interstellar flight is energetics — it takes vast amounts of energy to accelerate even small ships to 20% the speed of light. But what if we could steal that energy from where? Perhaps even a black hole. Enter the “halo drive”, a video by Prof David Kipping based on his new peer-reviewed research paper on the subject.
This video is based on research conducted at the Cool Worlds Lab at Columbia University, New York. You can now support our research program directly here: https://www.coolworldslab.com/support.
There’s an error in the video at around 8:30, 2 trillion joules is the cumulative energy output of a typical nuclear power station after 2000 seconds, not 20 days.
Backwards through time? We travel forwards every day, but traveling back could let us change our past, visit old friends, or manipulate the timeline to our benefit… Although our knowledge of space and time remains incomplete, we can still use what we know to consider possible time machines. But what kind of paradoxes would this entail and how can we resolve them? Join us today on a special journey through time.
An educational video written and presented by Professor David Kipping.
This video is based on research conducted at the Cool Worlds Lab at Columbia University, New York. You can now support our research program directly here: https://www.coolworldslab.com/support.
Further reading and resources: ► Echeverria, F., Klinkhammer, G. & Thorne, K. S. (1991), “Billiard balls in wormhole spacetimes with closed timelike curves: Classical theory”, Phys. Rev. D., 44, 1077: https://ui.adsabs.harvard.edu/abs/1991PhRvD…44.1077E/abstract. ► S. Kalyana Rama & Siddhartha Sen (1994), “Inconsistent Physics in the Presence of Time Machines”: https://arxiv.org/abs/gr-qc/9410031v1 ► Stephen Hawking (1992), “Chronology protection conjecture”, Phys. Rev. D., 46603: https://ui.adsabs.harvard.edu/abs/1992PhRvD…46…603H/abstract. ► Max Tegmark (1997), “On the dimensionality of space time”, CQG, 14, L69: https://arxiv.org/abs/gr-qc/9702052
A study reveals that light from these galaxies traveled for 13.4 billion years.
A study by an international team of astronomers has identified a group of the earliest galaxies confirmed to date. The team based its findings on the data processed by NASA’s James Webb Space Telescope (JWST). The galaxies are estimated to be less than 400 million years after the big bang, and light from these sources has taken roughly 13.4 billion years to reach the Earth’s atmosphere.
Sololos/iStock.
Astronomer and co-author, Emma Curtis-Lake from the University of Hertfordshire in the United Kingdom said that “it was crucial to prove that these galaxies do, indeed, inhabit the early universe. It’s very possible for closer galaxies to masquerade as very distant galaxies.”
Big Bang theory is widely accepted, it is still a theory and there is ongoing research & debate whether the Big Bang didn’t happen or not. Lets discuss in detail.
Light that has traveled for over 13.4 billion years to reach our neighborhood of space has been confirmed as originating from the earliest, most distant galaxy detected yet.
That places the most distant of these four very young objects at the very dawn of the Universe, just a short time after the Big Bang – a time period when the Universe was still foggy and bleary and the first rays of light were penetrating the darkness.
So detailed are the JWST’s long spectroscopic observations that researchers can not only measure the distance the light of these galaxies has traveled, they can also infer some of the galaxies’ properties.
