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Black holes form natural time machines that allow travel to both the past and the future. But don’t expect to be heading back to visit the dinosaurs any time soon.

At present, we don’t have spacecraft that could get us anywhere near a black hole. But, even leaving that small detail aside, attempting to travel into the past using a black hole might be the last thing you ever do.

Black holes are areas of space-time where gravity rules supreme: A black hole’s gravitational pull is so strong that nothing, not even light, can escape. They range in size from stellar-mass black holes, whose masses can range from five to 100 times that of the Sun, to supermassive black holes, whose masses can exceed a billion solar masses. Astronomers now believe that supermassive black holes exist at the center of most galaxies. (A notable exception to this rule is M33, which appears to lack a central supermassive black hole despite being the third largest member of our Local Group.)

In November 2018, three physicists from the Perimeter Institute for Theoretical Physics in Waterloo, Canada, offered an unusual idea: from the Big Bang not only the Universe we know but also ‘its mirror image’ created.

Twin spiral galaxies and stars in space. NASA provided picture elements. A universe that extends backward in time. From our perspective, the Universe “after the Big Bang” moves… backwards.

The physicists Latham Boyle, Keran Finn, and Neil Turok suggested in a Physical Review Letters article that the Universe we live in is merely a fragment of the true Universe and that if so, dark matter and inflation would no longer make sense.

Black Holes are fascinating yet mysterious cosmic objects scattered across the Universe. Unfortunately, we don’t know much about them, and we barely managed to snap a photo of one located in another galaxy.

But, what exactly are black holes?

Per definition, a black hole is an astronomical object with such a strong gravitational pull that nothing, not even light, can escape from it. The “surface” of a black hole, called the event horizon, defines the limit where the speed required to evade it exceeds the speed of light, which is the speed limit in the cosmos. As a result, matter and radiation are trapped and cannot get out.

Sam Baron, Australian Catholic University.

Black holes form natural time machines that allow travel to both the past and the future. But don’t expect to be heading back to visit the dinosaurs any time soon. At present, we don’t have spacecraft that could get us anywhere near a black hole. But, even leaving that small detail aside, attempting to travel into the past using a black hole might be the last thing you ever do.

Neutron stars and black holes may be stellar corpses, but they are among the most active celestial objects. They produce some of the highest-energy radiation ever observed, and scientists have long puzzled over the physics that underlies the process powering their energetic emissions.

Now, in a recent paper published in Physical Review Letters, a Dartmouth physics major and an assistant professor have proposed a new theory that explains how can be very quickly released with explosive energy into charged particles in these .

Similar magnetic explosions also occur closer to home, setting off and the Northern Lights. They can be observed wherever charged gases, called plasma, are found—even in a lab, says Matthew Goodbred ‘23, the paper’s lead author.

Using NASA’s Fermi spacecraft, Chinese astronomers have investigated the variability and spectral behavior of gamma-ray flares in a distant blazar known as 3C 279. Results of the study, presented in a paper published in the Publications of the Astronomical Society of the Pacific, could help researchers better understand the flaring activity of blazars.

Blazars are very compact quasars associated with at the centers of active, giant elliptical galaxies. Based on their optical emission properties, astronomers divide blazars into two classes: (FSRQs) that feature prominent and broad optical emission lines, and BL Lacertae objects (BL Lacs), which do not.

At a distance of about 5 billion , 3C 279 is an FSRQ with an estimated black hole mass of 300–800 million solar masses. It is a bright and powerful source in the high– sky and is known as the first blazar showing strong and rapid variability at GeV energies.

It can also rotate 220 degrees and lift up to 26.5 ounces of weight.

Supernova, a South Korean startup, has designed HUENIT, a robotic arm to help people with various household chores and creative tasks. Supernova showcased its AI Camera and Robot Arm at CES 2023. The company has been developing innovative robots to help people with everyday tasks.

Although many innovative technologies were showcased at the CES 2023, the Huenit Robot Arm captured the attention of visitors. HUENIT is an easy-to-use AI-based multi-functional robotic arm that combines advanced AI technologies with a modular arm to work on complex tasks with high precision. The robot can do everything from making coffee to 3D printing a prototype.