Lifeboat Foundation

Last week, NASA’s Perseverance Rover captured a gorgeous view of Phobos eclipsing the Sun, from the surface of Mars. From the point of view of any Martian microbes lurking out there, the eclipse may have seemed more ominous (yeah ok, there might not be living organisms up there, let alone ones sentient enough to grasp the concept of an eclipse) as the moon is destined by physics to one day slam into the red planet.

Phobos – the closest of Mars’ two moons – is set to get ever closer to the planet, before its final descent, while Deimos will drift ever outwards until it leaves Mars’ orbit.

Have you ever made a mistake that you wish you could undo? Correcting past mistakes is one of the reasons we find the concept of time travel so fascinating. As often portrayed in science fiction, with a time machine, nothing is permanent anymore – you can always go back and change it. But is time travel really possible in our universe, or is it just science fiction?

Our modern understanding of time and causality comes from general relativity. Theoretical physicist Albert Einstein’s theory combines space and time into a single entity – “spacetime” – and provides a remarkably intricate explanation of how they both work, at a level unmatched by any other established theory.

Continue reading “There’s One Way Time Travel Could Be Possible, According to This Physicist” »

An international team of astronomers reports the discovery of a rare double neutron star millisecond pulsar. The newfound binary pulsar, designated PSR J1325−6253, consists of two neutron stars orbiting one another every 1.8 days. The finding is detailed in a paper published April 14 on arXiv.org.

The most rapidly rotating pulsars, those with rotation periods below 30 milliseconds, are known as millisecond pulsars (MSPs). It is assumed that they are formed in binary systems when the initially more massive component turns into a neutron star that is then spun-up due to accretion of matter from the secondary star.

Some pulsars consist of two neutron stars (dubbed double neutron star systems—DNS). They are one of the most important classes of objects used to test and understand numerous astrophysical and fundamental physics phenomena, including general relativity in the strong-field regime.

As the early universe cooled shortly after the Big Bang, bubbles formed in its hot plasma, triggering gravitational waves that could be detectable even today, a new study suggests.

For some time, physicists have speculated that a phase transition took place in the early universe shortly after the Big Bang. Phase transition is a change of form and properties of matter that usually accompanies temperature changes such as the evaporation of water into vapor or the melting of metal. In the young and fast expanding universe, something similar likely took place as the plasma, which was filling the space at that time, cooled down.

The BBC gets an exclusive look at the upgraded machine helping to overhaul our understanding of the Universe.

The first detection of gravitational waves in 2016 provided decisive confirmation of Einstein’s general theory of relativity. But another astounding prediction remains unconfirmed: According to general relativity, every gravitational wave should leave an indelible imprint on the structure of space-time. It should permanently strain space, displacing the mirrors of a gravitational wave detector even after the wave has passed.

Since that first detection almost six years ago, physicists have been trying to figure out how to measure this so-called “memory effect.”

“The memory effect is absolutely a strange, strange phenomenon,” said Paul Lasky, an astrophysicist at Monash University in Australia. “It’s really deep stuff.”

Can we find order in chaos? Physicists have shown, for the first time that chaotic systems can synchronize due to stable structures that emerge from chaotic activity. These structures are known as fractals, shapes with patterns which repeat over and over again in different scales of the shape. As chaotic systems are being coupled, the fractal structures of the different systems will start to assimilate with each other, taking the same form, causing the systems to synchronize.

If the systems are strongly coupled, the fractal structures of the two systems will eventually become identical, causing complete synchronization between the systems. These findings help us understand how synchronization and self-organization can emerge from systems that didn’t have these properties to begin with, like chaotic systems and biological systems.

One of the biggest challenges today in physics is to understand chaotic systems. Chaos, in physics, has a very specific meaning. Chaotic systems behave like random systems. Although they follow deterministic laws, their dynamics still will change erratically. Because of the well-known “butterfly effect” their future behavior is unpredictable (like the weather system, for example).

Josh SeehermanI don’t think he’s wrong.

Art ToegemannIt’s adjusting to users sharing a password.

Shubham Ghosh Roy shared a link.

Continue reading “Revolutionary images of the birth of crystals” »