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Feb 22, 2024

Microscopic Origin of the Entropy of Black Holes in General Relativity

Posted by in categories: cosmology, quantum physics

In the 1970s, physicists Bekenstein and Hawking used general relativity and quantum mechanics in curved spacetime to propose that black holes behave as thermodynamic objects. They found that black holes carry an entropy described by a remarkable formula that applies for any mass, charge, angular momentum, or spacetime dimension. Here, we use new results at the interface of quantum information theory and quantum gravity to address an outstanding challenge: how to explain the microscopic origin of this formula.

In quantum mechanics, entropy measures the logarithm of the dimension of the space of microstates consistent with the macroscopic description of a system. We show that, in any theory of gravity that reduces to general relativity with matter at low energies, there are infinite families of states that have geometries identical to the black hole outside the horizon but different structures inside. We show that these states overlap quantum mechanically because of gravitational wormholes. The overlaps have a dramatic consequence: The microstates span a space whose dimension equals the exponential of the Bekenstein-Hawking entropy formula.

This explanation of black-hole entropy does not require new forms of matter and involves a novel description of all black-hole microstates as quantum superpositions of objects having geometric semiclassical descriptions. Our results also imply a macroscopic manifestation of quantum mechanics in cosmic settings: We show that one can understand long Einstein-Rosen bridges between universes as quantum superpositions of short bridges.

Feb 22, 2024

A New Sensor for Rapid, Simple Skin Cancer Detection

Posted by in categories: biotech/medical, electronics

A new tool has been developed to detect skin cancer; it utilizes a biosensor that can identify small changes in the characteristics of cells. | Clinical And Molecular Dx.

Feb 22, 2024

NASA-built tech lets paralyzed people communicate with eye movements

Posted by in categories: biotech/medical, innovation

Envision a game-changing technology that grants the power of expression to those facing speech challenges.

An innovative solution has emerged thanks to an incredible collaboration between NASA’s Jet Propulsion Laboratory and Eyegaze Inc.

They have created Eyegaze Edge, an eye-driven communication device.

Feb 22, 2024

MEGA-CRISPR tool gives a power boost to cancer-fighting cells

Posted by in category: biotech/medical

A system that edits RNA rather than DNA can give new life to exhausted CAR T cells.

Feb 22, 2024

Opinion: Brilliant adoption of AI

Posted by in category: robotics/AI

Khan Academy has come up with a safe and accurate ChatGPT tutor. It’s also the best model we have for how to develop and implement AI for the public good.

Feb 22, 2024

Unearthing Mars’ Watery Past: Insights from Groundwater Recharge Dynamics

Posted by in categories: computing, space

“The fact that the groundwater isn’t as big of a process could mean that other things are,” said Eric Hiatt. “It might magnify the importance of runoff, or it could mean that it just didn’t rain as much on Mars. But it’s just fundamentally different from how we think about [water] on Earth.”

How much water on ancient Mars fell into aquifers to refill groundwater? This is what a recent study published in Icarus hopes to address as a team of international researchers led by The University of Texas at Austin (UTA) used computer models to calculate groundwater recharge rates in the southern highlands of ancient Mars. This study holds the potential to help scientists better understand the amount of water that potentially existed on ancient Mars and what this could mean for finding ancient life on the Red Planet.

For the study, the researchers used a combination of previously used and new computer modeling techniques to estimate how much groundwater recharge occurred in the Martian southern highlands, since most of the liquid water that existed on Mars billions of years ago resided in a vast ocean in the northern lowlands. In the end, the researchers found the aquifers in the southern highlands on Mars experienced an average groundwater recharge of only 0.03 millimeters (0.001 inches) per year. For context, the Trinity and Edwards-Trinity Plateau aquifers that are responsible for providing water for the city of San Antonio range between 2.5 to 50 millimeters (0.1 inches to 2 inches) per year, or between 80 and 1,600 times that of the Martian aquifers.

Continue reading “Unearthing Mars’ Watery Past: Insights from Groundwater Recharge Dynamics” »

Feb 22, 2024

Sagittarius A*: Spinning Black Hole Shapes Spacetime into Football

Posted by in categories: cosmology, physics

“A spinning black hole is like a rocket on the launch pad,” said Dr. Biny Sebastian. “Once material gets close enough, it’s like someone has fueled the rocket and hit the ‘launch’ button.”

The center of our Milky Way Galaxy is exhibiting spinning behavior while warping the spacetime environment, according to a recent study published in the Monthly Notices of the Royal Astronomical Society. A team of international researchers led by Penn State University investigated the spinning patterns of the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A, which is located approximately 26,000 light-years from Earth, and holds the potential to help astrophysicists better understand the behavior of black holes throughout the cosmos.

“A spinning black hole is like a rocket on the launch pad,” said Dr. Biny Sebastian, who is a researcher in the Department of Physics & Astronomy at the University of Manitoba and a co-author on the study. “Once material gets close enough, it’s like someone has fueled the rocket and hit the ‘launch’ button.”

Continue reading “Sagittarius A*: Spinning Black Hole Shapes Spacetime into Football” »

Feb 22, 2024

The Zombie Star That Could Solve the Mystery of the Universe’s Strongest Magnets

Posted by in category: space

Magnetars are the strongest magnets in the universe. These super-dense dead stars with ultra-strong magnetic fields can be found all over our galaxy but astronomers don’t know exactly how they form.

Now, using multiple telescopes around the world, including European Southern Observatory (ESO) facilities, researchers have uncovered a living star that is likely to become a magnetar. This finding marks the discovery of a new type of astronomical object—massive magnetic helium stars—and sheds light on the origin of magnetars.

Despite having been observed for over 100 years, the enigmatic nature of the star HD 45,166 could not be easily explained by conventional models, and little was known about it beyond the fact that it is one of a pair of stars, is rich in helium and is a few times more massive than our sun.

Feb 22, 2024

Man feels hot and cold again with prosthetic hand breakthrough

Posted by in categories: biotech/medical, cyborgs

Researchers have built a device that helps users feel temperature through a prosthetic arm. A new study shows it works with high accuracy.

Feb 22, 2024

24 Best Longevity Conferences and Events for 2024

Posted by in category: life extension

For this long overdue update of top longevity conferences we’ve removed 5 old events no longer happening and added a whopping 12 new ones!

We’ve put together the most up-to-date list of longevity conferences where you can learn about life-extension research in-person and online.

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