Physicists are interested in the big questions like “Where did we come from?” and “What is all this stuff?”. But the answers to some of these questions, just lead to more questions.
Hosted by: Michael Aranda.
Continue reading “4 of Physics’ (Other) Greatest Mysteries” »
When we look into the night sky, we see the universe as it once was. We know that in the past, the universe was once warmer and denser than it is now. When we look deep enough into the sky, we see the microwave remnant of the big bang known as the cosmic microwave background. That marks the limit of what we can see. It marks the extent of the observable universe from our vantage point.
The cosmic background we observe comes from a time when the universe was already about 380,000 years old. We can’t directly observe what happened before that. Much of the earlier period is fairly well understood given what we know about physics, but the earliest moments of the big bang remain a bit of a mystery. According to the standard model, the earliest moments of the universe were so hot and dense that even the fundamental forces of the universe acted differently than they do now. To better understand the big bang, we need to better understand these forces.
One of the more difficult forces to understand is the weak force. Unlike more familiar forces such as gravity and electromagnetism, the weak is mostly seen through its effect of radioactive decay. So we can study the weak force by measuring the rate at which things decay. But there’s a problem when it comes to neutrons.
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Find out how scientists are mapping the black holes throughout the Milky Way and beyond as well as the answer to the Escape the Kugelblitz Challenge Question. Were you able to save humanity?
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Speaking at the 6th International FQXi Conference, “Mind Matters: Intelligence and Agency in the Physical World.”
The Foundational Questions Institute (FQXi) catalyzes, supports, and disseminates research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality but unlikely to be supported by conventional funding sources.
Continue reading “Joscha Bach — Reconciling consciousness with physicalism” »
Solutions to the problems of interstellar travel
Given the insane scale of interstellar distances, how might we extrapolate from the physics we do understand to envisioning possible ways that aliens (or us in the future) could cross the cosmic void? There are a few possible solutions to the problem of interstellar travel.
A bold claim, I know. It won’t surprise you to find out that I want to stick some qualifiers on it. For the purposes of this article, “futurists” means educated industry analysts and hard science fiction authors with a comprehensive knowledge of physics.
On Wednesday, CEO Elon Musk outlined how the company’s under-development rocket will deliver a “high fly rate” of a dozen launches in 2022. This will enable the ship to deliver actual payloads in 2023 before moving on to more ambitious goals like sending humans to the Moon and Mars.
https://www.youtube.com/watch?v=rLydXZOo4eA
The comments, made at the joint meeting of the Space Studies Board and the Board on Physics and Astronomy, outline how the stainless steel rocket taking shape in Texas will move from prototype curiosity to working ship.
Continue reading “SpaceX Starship 2022: How next year will pave way for Mars City and Artemis” »
Today, the greatest mysteries facing astronomers and cosmologists are the roles gravitational attraction and cosmic expansion play in the evolution of the Universe.
To resolve these mysteries, astronomers and cosmologists are taking a two-pronged approach. These consist of directly observing the cosmos to observe these forces at work while attempting to find theoretical resolutions for observed behaviors – such as dark matter and dark energy.
In between these two approaches, scientists model cosmic evolution with computer simulations to see if observations align with theoretical predictions. The latest of which is AbacusSummit, a simulation suite created by the Flatiron Institute’s Center for Computational Astrophysics (CCA) and the Harvard-Smithsonian Center for Astrophysics (CfA).
If you think of very low temperatures, there’s a good chance you are picturing ice. Ice is a quintessential “cold” thing for us. But at extreme pressures, like in the core of large planets, something peculiar can happen. Ice can remain solid but have a temperature hotter than the surface of the Sun.
This type of water ice is called “superionic ice” and has been added to the list of around 20 phases water can structurally form, including ice, liquid, and vapor. Now, researchers report in Nature Physics the discovery and characterization of two superionic ice phases, having found a way of reliably and stably recreating the ice for longer than has previously been achieved to be able to study it.
One superionic phase extends between 200,000 and 60,000 times the atmospheric pressure at sea level and at a temperature of several hundred to over 1,000 ° C. The other phase extends to half the pressure experienced at the center of the Earth and with temperatures of thousands of degrees.
