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.
Contact electrification (CE) was humanity’s earliest and sole source of electricity until about the 18th century, but its real nature remains a mystery. Today, it is regarded as a critical component of technologies such as laser printers, LCD production processes, electrostatic painting, plastic separation for recycling, and more, as well as a major industrial hazard (damage to electronic systems, explosions in coal mines, fires in chemical plants) due to the electrostatic discharges (ESD) that accompany CE. A 2008 study published in Nature found that in a vacuum, ESDs of a simple adhesive tape are so powerful that they generate enough X-rays to take an X-ray image of a finger.
For a long time, it was believed that two contacting/sliding materials charge in opposing and uniform directions. However, after CE, it was discovered that each of the separated surfaces carries both (+) and (-) charges. The formation of so-called charge mosaics was attributed to experiment irreproducibility, inherent inhomogeneities of contacting materials, or the general “stochastic nature” of CE.
What is driving the mulitverse theory? Are the multiverse stories only a sticky-plaster solution to the Big Bang theory problem? Leading thinkers Sabine Hossenfelder, Roger Penrose and Michio Kaku debate.
00:00 Introduction. 02:22 Michio Kaku | Multiverse theory has now dominating cosmology; it is unavoidable. 06:03 Sabine Hossenfelder | Believing in the multiverse is the logical equivalent to believing in God. 07:57 Roger Penrose | Universes are sequential and so are not independent worlds. 16:36 Theme 1 | Do scientifc theories need to be testable? 28:45 Theme 2 | Are tales of the multiverse solutions to the Big Bang theory in trouble? 42:49 Theme 3 | Will theories of the universe always be bound by untestable elements?
Multiverses are everywhere. Or at least the theory is. Everyone from physicists Stephen Hawking and Brian Greene to Marvel superheroes have shown their support for the idea. But critics argue that not only is the multiverse improbable, it is also fantasy and fundamentally unscientific as the theory can never be tested — a requirement that has defined science from its outset.
Should we reject the grand claims and leave multiverse theories to the pages of comic books? Are tales of the multiverse really sticking-plaster solutions for Big Bang theory in trouble? Or should we take multiverse theory as seriously as its proponents, and accept that modern science has moved beyond the bounds of experiment and into that of imagination?
Michio Kaku is the co-founder of string field theory and the author of several books including several New York Times best sellers such as ‘The God Equation: The Quest for a Theory of Everything became.’ He is also professor of theoretical physics in the City College of New York and CUNY Graduate Center.
Debates about the existence of free will have traditionally been fought by two competing camps: those who believe in free will and those who don’t because they believe the Universe is deterministic.
Determinism is the thesis that every event — from when a volcano erupts to what cereal you buy at the supermarket — is a theoretically predictable result of the long chain of events that came before it. Free will, it was long thought, cannot exist in a world where all events are already causally determined.
But free will and determinism aren’t necessarily mutually exclusive. As physicist Sean Carroll told Big Think, the compatibilist conception of free will argues that it makes sense to conceptualize ourselves as able to make free decisions, regardless of whether the Universe is deterministic or indeterministic.
Why? The main argument centers on the phenomenon of emergence.
A recent study of the star’s surface, published in the journal Nature Astronomy, says that we’re seeing Gamma Columbae in a short, deeply weird phase of a very eventful stellar life, one that lets astronomers look directly into the star’s exposed heart.
What’s New – The mix of chemical elements on the surface of Gamma Columbae look like the byproducts of nuclear reactions that should be buried in the depths of a massive star, not bubbling on its surface.
The observations could not be explained by Newton’s law of universal gravitation. An alternative theory of gravity might provide the answer. Astrophysicists observed mysterious behavior in star clusters that could lead to a rewrite of fundamental principles of the theory of gravity and even disprove the existence of dark matter, a press release explains.
The new findings challenge existing preconceptions based on widely-accepted principles from Newton’s law of universal gravitation, which explain the large-scale structure and movements of the universe.
An analysis of more than two decades’ worth of supernova explosions convincingly boosts modern cosmological theories and reinvigorates efforts to answer fundamental questions.
A powerful new analysis has been performed by astrophysicists that places the most precise limits ever on the composition and evolution of the universe. With this analysis, dubbed Pantheon+, cosmologists find themselves at a crossroads.
Pantheon+ convincingly finds that the cosmos is made up of about two-thirds dark energy and one-third matter — predominantly in the form of dark matter — and is expanding at an accelerating pace over the last several billion years. However, Pantheon+ also cements a major disagreement over the pace of that expansion that has yet to be solved.
A team of astrophysicists has revealed an unusual discovery they say appears to challenge our current understanding of gravity based on Newton’s law of universal gravitation, according to a newly published paper.
The controversial claim, published in the Monthly Notices of the Royal Astronomical Society, appears to be consistent with alternative interpretations about one of physics’ most mysterious fundamental interactions.
In their new study, an international team of astrophysicists says that they came upon the discovery while investigating open star clusters. These formations are created as a gas cloud emerges following the birth of thousands of stars within a relatively short time, the remnants of which are ejected as these clusters of stars ignite and begin to expand, which can result in the formation of anywhere from several dozen, to several thousands of new stars.
