Lifeboat Foundation

Gamma-ray bursts (GRBs) have been detected by satellites orbiting Earth as luminous flashes of the most energetic gamma-ray radiation lasting milliseconds to hundreds of seconds. These catastrophic blasts occur in distant galaxies, billions of light years from Earth.

A sub-type of GRB known as a short-duration GRB starts life when two neutron stars collide. These ultra-dense stars have the mass of our sun compressed down to half the size of a city like London, and in the final moments of their life, just before triggering a GRB, they generate ripples in space-time—known to astronomers as gravitational waves.

Until now, space scientists have largely agreed that the “engine” powering such energetic and short-lived bursts must always come from a newly formed black hole (a region of space-time where gravity is so strong that nothing, not even light, can escape from it). However, new research by an international team of astrophysicists, led by Dr. Nuria Jordana-Mitjans at the University of Bath, is challenging this scientific orthodoxy.

Spin glasses are alloys formed by noble metals in which a small amount of iron is dissolved. Although they do not exist in nature and have few applications, they have nevertheless been the focus of interest of statistical physicists for some 50 years. Studies of spin glasses were crucial for Giorgio Parisi’s 2021 Nobel Prize in Physics.

The scientific interest of spin glasses lies in the fact that they are an example of a complex system whose elements interact with each other in a way that is sometimes cooperative and sometimes adversarial. The mathematics developed to understand their behavior can be applied to problems arising in a variety of disciplines, from ecology to machine learning, not to mention economics.

Spin glasses are magnetic systems, that is, systems in which individual elements, the spins, behave like small magnets. Their peculiarity is the co-presence of ferromagnetic-type bonds, which tend to align the spins, with antiferromagnetic-type bonds, which tend to orient them in opposite directions.

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 on all scales.

General relativity has passed many years of observational tests, from Eddington’s measurement of the deflection of starlight by the Sun in 1919 to the recent detection of gravitational waves.

Physicists agree, one day it may be possible for a person to create a universe. It won’t happen tomorrow, but the idea is in the works. There’s already one problem with the idea: If a universe is created, physicists say they wouldn’t know how to communicate with it.

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Continue reading “What If Humanity Is Among The First Spacefaring Civilizations?” »

As in physics, paradoxes in biology really are just unsolved puzzles. Enter Peto’s paradox. Biologist Richard Peto noticed in the 1970s that mice had a much higher rate of cancer than humans do, which doesn’t make any sense. Humans have over 1,000 times as many cells as mice, and cancer is simply a rogue cell that goes on multiplying out of control. One would expect humans to be more likely to get cancer than smaller creatures such as mice. This paradox occurs across all species, too: blue whales are much less likely to get cancer than humans, even though they have many more cells in their bodies.

Fermi paradox

Continue reading “10 Paradoxes That Will Stretch Your Mind” »

Physicists are devising clever new ways to exploit the extreme sensitivity of gravitational wave detectors like LIGO. But so far, they’ve seen no signs of exotica.

Earth’s low orbit is filling up, meaning radiation-tolerant cell designs are required as satellites head to higher orbits. Will these new ones do?

Scientists have developed a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material. According to a new study published today (Nov .08) in the Journal of Applied Physics by AIP Publishing.

Significantly, the ultra-thin solar cells not only surpass earlier suggested thicker solar cells in resilience to irradiation; they also produce the same amount of power from converted sunlight after 20 years of use. Additionally, the novel photovoltaic cells could reduce load and considerably lower launch expenses. Barthel.

You can imagine starting at the beginning, evolving the Universe forward according to the laws of physics, and measuring those earliest signals and their imprints on the Universe to determine how it has expanded over time. Alternatively, you can imagine starting here and now, looking out at the distant objects as we see them receding from us, and then drawing conclusions as to how the Universe has expanded from that.

Both of these methods rely on the same laws of physics, the same underlying theory of gravity, the same cosmic ingredients, and even the same equations as one another. And yet, when we actually perform our observations and make those critical measurements, we get two completely different answers that don’t agree with one another. This is, in many ways, the most pressing cosmic conundrum of our time. But there’s still a possibility that no one is mistaken and everyone is doing the science right. The entire controversy over the expanding Universe could go away if just one new thing is true: if there was some form of “early dark energy” in the Universe. Here’s why so many people are compelled by the idea.