The IceCube Neutrino Observatory, operated by the University of Wisconsin-Madison (UW-M), located at the Amundsen–Scott South Pole Station in Antarctica, is one of the most ambitious neutrino observatories in the world. Behind this observatory is the IceCube Collaboration, an international group of 300 physicists from 59 institutions in 14 countries. Relying on a cubic kilometer of ice to shield from external interference, this observatory is dedicated to the search for neutrinos. These nearly massless subatomic particles are among the most abundant in the Universe and constantly pass through normal matter.
Someday, in the not-too-distant future, humans may send robotic probes to explore nearby star systems. These robot explorers will likely take the form of lightsails and wafercraft (a la Breakthrough Starshot) that will rely on directed energy (lasers) to accelerate to relativistic speeds – aka. a fraction of the speed of light. With that kind of velocity, lightsails and wafercraft could make the journey across interstellar space in a matter of decades instead of centuries (or longer!) Given time, these missions could serve as pathfinders for more ambitious exploration programs involving astronauts.
Of course, any talk of interstellar travel must consider the massive technical challenges this entails. In a recent paper, a team of engineers and astrophysicists considered the effects that relativistic space travel will have on communications. Their results showed that during the cruise phase of the mission (where a spacecraft is traveling close to the speed of light), communications become problematic for one-way and two-way transmissions. This will pose significant challenges for crewed missions but will leave robotic missions largely unaffected.
“Oh My God,” someone must have said in 1991 when researchers detected the most energetic cosmic ray ever to strike Earth. Those three words were adopted as the name for the phenomenon: the Oh-My-God particle. Where did it come from?
Near the end of his life Einstein worked tirelessly to find a way to unite electromagnetism with gravity. He could not, and never did, the notes scattered on his desk scrawled with fruitless probes and useless hypotheticals. Indeed, Einstein passed without even understanding why the two forces could not be united.
It started with a simple experiment that was all the rage in the early 20th century. And as is usually the case, simple experiments often go on to change the world, leading Einstein himself to open the revolutionary door to the quantum world.
In Einstein’s famous theory of relativity the concepts of immutable space and time aren’t just put aside, they’re explicitly and emphatically rejected. Space and time are now woven into a coexisting fabric. That is to say, we truly live in a four-dimensional universe. Space and time alone cease to exist; only the union of those dimensions remains.
The theory of relativity is at once simple and elegant but also maddeningly nonintuitive. There’s no need to get into the full guts and glory of that theory here, but there is one feature of Einstein’s work that takes center stage, and would eventually lead him into a complete reshaping of Newton’s gravity, altering our very conceptions of the fabric of the universe.
But who else? In a new book titled “Her Space, Her Time,” quantum physicist Shohini Ghose explains why women astronomers and physicists have been mostly invisible in the past — and profiles 20 researchers who lost out on what should have been Nobel-level fame.
“This issue around having low representation of women in physics is something that’s common all around the world,” Ghose says in the latest episode of the Fiction Science podcast. “And I’ve certainly faced it in my own experiences as a physicist growing up. I really didn’t know of any woman physicist apart from Marie Curie.”
Time travel. We’ve all thought about it at one time or another, and the subject has been explored extensively in science fiction. Once in a while, it is even the subject of scientific research, typically involving quantum mechanics and how the Universe’s four fundamental forces (electromagnetism, weak and strong nuclear forces, and gravity) fit together. In a recent experiment, researchers at the University of Cambridge showed that by manipulating quantum entanglements, they could simulate what could happen if the flow of time were reversed.