In 1900, so the story goes, prominent physicist Lord Kelvin addressed the British Association for the Advancement of Science with these words: “There is nothing new to be discovered in physics now.”
How wrong he was. The following century completely turned physics on its head. A huge number of theoretical and experimental discoveries have transformed our understanding of the universe, and our place within it.
Don’t expect the next century to be any different. The universe has many mysteries that still remain to be uncovered—and new technologies will help us to solve them over the next 50 years.
Ira Pastor, ideaXme exponential health ambassador, interviews Dr. Ronald Mallett, Professor Emeritus, Theoretical Physics, Department of Physics at the University of Connecticut.
Ira Pastor Comments:
Time travel is the concept of movement between certain points in time, analogous to movement between different points in space, by an object or a person, typically with the use of a hypothetical device known as a time machine.
Time travel is a widely recognized concept in philosophy and fiction and the idea of a time machine was originally popularized by H. G. Wells’ 1895 novel The Time Machine.
Forward time travel, outside the usual sense of the perception of time, is an extensively observed phenomenon and well-understood within the framework of special relativity and general relativity and making one body advance a few milliseconds compared to another body has been demonstrated in experiments comparing atomic clocks on jets and satelites versus the earth.
As for backward time travel, it is possible to find solutions in general relativity that allow for it, in a theoretical system known as a “closed timelike curve” (sometimes abbreviated CTC), which is where the world line of an object (the path that an object traces in 4-dimensional space-time) follows a curious path where it eventually returns to the exact same coordinates in space and time that it was at previously. In other words, a closed timelike curve is the mathematical result of physics equations that allows for time travel to the past.
In 2016, Attila Krasznahorkay made news around the world when his team published its discovery of evidence of a fifth force of nature. Now, the scientists are making news again with a second observation of the same force, which may be the beginning of a unified fifth force theory. The researchers have made their original LaTeX paper available prior to acceptance by a peer-reviewed journal. Study of the hypothesized fifth force, a subfield all by itself, is centered on trying to explain missing pieces in our understanding of physics, like dark matter, which could be expanded or validated by an important new discovery or piece of evidence.
Scientists hope that the future of gravitational wave detection will allow them to directly observe a mysterious kind of black hole.
Gravitational wave detectors have seen direct evidence of black holes with roughly the mass of giant stars, while the Event Horizon Telescope produced an image of a supermassive black hole billions of times the mass of our Sun. But in the middle are intermediate-mass black holes, or IMBHs, which weigh between 100 and 100,000 times the mass of the Sun and have yet to be directly observed. Researchers hope that their new mathematical work will “pave the way” for future research into these black holes using gravitational wave detectors, according to the paper published today in Nature Astronomy.
Physicists use two types of measurements to calculate the expansion rate of the universe, but their results do not coincide, which may make it necessary to update the cosmological model. “It’s like trying to thread a cosmic needle,” explains researcher Licia Verde of the University of Barcelona, co-author of an article on the implications of this problem.
More than a hundred scientists met this summer at the Kavli Institute for Theoretical Physics at the University of California (U.S.) to try to clarify what is happening with the discordant data on the expansion rate of the universe, an issue that affects the very origin, evolution and fate of our cosmos. Their conclusions have been published in Nature Astronomy journal.
“The problem lies in the Hubble constant (H0), a parameter which value—it is actually not a constant because it changes with time—indicates how fast the Universe is currently expanding,” points out cosmologist Licia Verde, an ICREA researcher at the Institute of Cosmos Sciences of the University of Barcelona (ICC-UB) and the main author of the article.
Artificial muscles will power the soft robots and wearable devices of the future. But more needs to be understood about the underlying mechanics of these powerful structures in order to design and build new devices.
Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have uncovered some of the fundamental physical properties of artificial muscle fibers.
“Thin soft filaments that can easily stretch, bend, twist or shear are capable of extreme deformations that lead to knot-like, braid-like or loop-like structures that can store or release energy easily,” said L. Mahadevan, the Lola England de Valpine Professor of Applied Mathematics, of Organismic and Evolutionary Biology, and of Physics. “This has been exploited by a number of experimental groups recently to create prototypical artificial muscle fibers. But how the topology, geometry and mechanics of these slender fibers come together during this process was not completely clear. Our study explains the theoretical principles underlying these shape transformations, and sheds light on the underlying design principles.”