Einstein’s Predictions for Gravity Have Been Tested at the Largest Possible Scale

According to the Standard Model of Particle Physics, the Universe is governed by four fundamental forces: electromagnetism, the weak nuclear force, the strong nuclear force, and gravity. Whereas the first three are described by Quantum Mechanics, gravity is described by Einstein’s Theory of General Relativity. Surprisingly, gravity is the one that presents the biggest challenges … Read more

Something is wrong with Einstein’s theory of gravity

Everything in the universe has gravity – and feels it too. Yet this most common of all fundamental forces is also the one that presents the biggest challenges to physicists. Albert Einstein’s theory of general relativity has been remarkably successful in describing the gravity of stars and planets, but it doesn’t seem to apply perfectly … Read more

Pregnancy in space: studying stem cells in zero gravity may determine whether it’s safe

This article was originally published at The Conversation. (opens in new tab) The contributed the article to Space.com’s Expert Voices: Op-Ed & Insights. Joanna Bridger (opens in new tab)Director of the Center for Genome Engineering and Maintenance (CenGEM), Professor of Genome Organisation, Brunel University LondonEmmanouil Karteris (opens in new tab)Reader in Biomedical Sciences, Brunel University … Read more

Mars did Have Moving Glaciers, but They Behaved Differently in the Planet’s Lower Gravity

On Earth, shifts in our climate have caused glaciers to advance and recede throughout our geological history (known as glacial and inter-glacial periods). The movement of these glaciers has carved features on the surface, including U-shaped valleys, hanging valleys, and fjords. These features are missing on Mars, leading scientists to conclude that any glaciers on … Read more

Want to Stay Healthy in Space? Then you Want Artificial Gravity

Space travel presents numerous challenges, not the least of which have to do with astronaut health and safety. And the farther these missions venture from Earth, the more significant they become. Beyond Earth’s protective atmosphere and magnetosphere, there’s the threat of long-term exposure to solar and cosmic radiation. But while radiation exposure can be mitigated … Read more

A New Study Confirms That Gravity has Remained Constant for the Entire age of the Universe

For over a century, astronomers have known that the Universe has been expanding since the Big Bang. For the first eight billion years, the expansion rate was relatively consistent since it was held back by the force of gravitation. However, thanks to missions like the Hubble Space Telescope, astronomers have since learned that roughly five … Read more

Scientists help probe dark energy by testing gravity

This image – the first released from NASA’s James Webb Space Telescope – shows the galaxy cluster SMACS 0723. Some of the galaxies appear smeared or stretched due to a phenomenon called gravitational lensing. This effect can help scientists map the presence of dark matter in the universe. Credit: NASA, ESA, CSA, STScI Could one … Read more

Why is gravity so weak? The answer may lie in the very nature of space-time

Why is gravity so weak compared to the other four fundamental forces? Even if it were a billion times stronger, it would still be the weakest force — by a factor of a billion billion. The strange feebleness of gravity sticks out, almost demanding an answer. Strangely, the solution to gravity’s weakness may not lie … Read more

To get Artificial Gravity on the Moon, you’d need a Giant Rotating Lunar Base

Living and working in space for extended periods of time presents a number of challenges. These include radiation, as locations beyond Earth’s protective magnetosphere are exposed to greater levels of solar and cosmic rays. There’s also the need for self-sufficiency since Lunar or Martian bases are too far to rely on regular resupply missions like … Read more

It’s time to ditch dark matter in favor of a new theory of gravity.

The barred spiral galaxy UGC 12158. (Image credit: Wikimedia , CC BY-SA) This article was originally published at The Conversation. (opens in new tab) The contributed the article to Space.com’s Expert Voices: Op-Ed & Insights. Indranil Banik (opens in new tab)Postdoctoral Research Fellow of Astrophysics, University of St Andrews We can model the motions of … Read more