Can discovery of Gravitational waves unravel the mystery of quantum gravity?

With the discovery of gravitational waves, ripples in the fabric of space-time, scientists have finally been able to provide convincing evidence for the existence of black holes and confirming an enigmatic part of Einstein’s theory of relativity. The discovery is one of the most important climaxes of the century and may finally provide the fundamental understanding of the formation of the Universe.

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This article will not be related to gravitational waves fully, but will cover up another most important theory that has been the target of decades of study by physicists worldwide. If this idea is established, then the General Theory of Relativity can be combined with quantum mechanics eventually revolutionizing the field of subatomic particles.

Quantum gravity is a field of theoretical physics that deals with the force of gravity rendering to the principles of quantum mechanics, and where quantum effects cannot be ignored. Subatomic particles have different characteristics and some of them are quantized meaning they can only move or exist in particular whole number states. Many physicists believe gravitational waves are similarly quantized and are made up of individual quantum particles of gravity known as gravitons.

While there is no concrete proof of the existence of gravitons, quantized theories of matter may necessitate their existence. Some physicists believe that gravitons join together, forming gravitational waves that travel through space in the form of ripples. Like photons of light, gravitons are also considered massless and move at the speed of light.

In the center of black holes, effects of quantum gravity are predicted to be quite definite, however it is impossible to accumulate data from the events happening near a singularity. The scientists form LIGO (Laser Interferometer Gravitational Wave Observatory) used a set of instruments which was very sensitive, yet they could only identify a distortion in space-time, which is a thousandth the diameter of one atomic nucleus across a 4 km strip of laser-beam and mirror.

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LIGO Gravitational wave detected on Feb 11,2016

It is impossible for the LIGO detector or any advanced gravitational wave detector to detect a graviton in the space-time, leave alone proving the theory of relativity. But maybe in future a device so precisely modified is build, that it could finally detect the evidence of quantum gravity by examining the emission spectrum of energy surrounding the event horizons of black holes.

With LIGO , the astronomers have so far detected intangible ripples in space-time which is only the beginning of a new kind of physics. Further into the advancement of astronomical devices, they may come across other evidence of astrophysical theories such as cosmic strings, theoretical one-dimensional strings of energy, which may be there in the depth of space-time since the very beginning.

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The recorded data of the gravitational waves may also give the physicists to analyze the ripples in order to finally examine some evidence of gravitons which will eventually solve the mysterious puzzle of relativity theory. If the existence of gravitons is established, it could change the way of understanding gravity. Such a finding could suggest that other notions of gravity, such as string theory, could prove to be the basis of future work on the nature of gravity.

But until that time comes, the existence of gravitons are strictly theoretical.

Coupling of perovskites and quantum dots could improve LED and Solar technologies

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Solar energy is one of the cleanest and abundant form of free energy sources available. Already, the contribution of solar energy have a significant impact on human needs, solar technology is a growing, multibillion-dollar industry. But today’s commercial solar cells, most often made from silicon, typically convert sunlight into electricity with an efficiency of only 10 percent to 20 percent, although some test cells do a little better. This efficiency factor is the main concern for the scientists to deal with. Theoretically maximum efficiency of a solar cell can reach only up to 31 percent due to the electronic properties of the silicon material.

Researchers from Valencia have proposed a promising way to improve solar efficiency. They have successfully coupled two different components halide perovskites and colloidal quantum dots (QDs) and have come to a conclusion that the interaction between these two materials could improve LED and solar technologies. Both halide perovskites and colloidal quantum dots are separately known for their optoelectronic properties when interacted together these materials produce much longer wavelengths than can be achieved by either material alone.

Perovskite materials are the fastest advance solar technology in the photo-voltaic industry to date, plus they are cheap to produce, simple to manufacture and extremely efficient. The perovskite materials have a lot of potential to improve the efficiency further and are still very much in the research area. They are also used in LED technology.
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Quantum dots (QDs), on the other hand, are semiconductor devices that tightly restrain electrons or holes in all three spatial dimensions. They can be made via several possible routes including colloidal synthesis, plasma synthesis, or mechanical fabrication. Quantum Dots has the ability to tune whatever wavelengths light is been emitted at it. They are also very useful in both LEDs and solar cells.

The two materials were coupled together in a lab research experiment and the results showed a new “exciplex” state where light can be emitted at much longer wavelengths, reaching well into the infrared spectrum. It also allowed controlling over the emission color by varying the applied voltage. Both the material (perovskite and the QDs) emitted light at a different color, each of which can be weighted within the overall light emission to pick out the desired color.

The success of this experiments has paved a new way in LED designing where it can now emit light over both the visible and infrared spectrum at the same time, which have both theoretical and practical aspects in the field of telecommunications.

Presently solar cells can only transform light emitted over a relatively
narrow band of wavelengths. But if it is possible to produce light at longer wavelengths via an electrical input, then the theoretical procedure of obtaining electrical energy by absorbing light of longer wavelengths will also be made possible, thereby helping in increasing the efficiency of solar cells.

The result of these two materials will have a greater impact on improving solar technology and will help solar power to affirm its superiority to fossil fuels as a sustainable motive force for civilization’s continued prosperity.

Galactic climate being affected by Black Holes

A prevailing galactic explosion produced by a giant black hole situated almost 26 million light years away from Earth has provoked a new leap in the field of cosmology. This is one of the nearest super-massive black holes to Earth and its frequent violent outbursts can somehow change the galactic climate is been proposed by a team of researchers led by Eric Schlegel, Professor of Physics at The University of Texas at San Antonio.

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The inset image shows X-ray arcs that astronomers say are signs of galactic burping in the Messier 51 galaxy system

Schlegel’s team used NASA’s Earth-orbiting Chandra X-ray Observatory to locate the black hole blast in the famous Messier 51 system of galaxies. The Messier 51 system contains a large spiral galaxy, NGC 5194, colliding with a smaller companion galaxy, NGC 5195.

“Just as powerful storms here on Earth impact their environments, so too do the ones we see out in space,” Schlegel said. “This black hole is blasting hot gas and particles into its surroundings that must play an important role in the evolution of the galaxy.”

Schlegel and his colleagues, including Fisk University graduate student and UTSA alumna Laura Vega, detected two X-ray emission arcs near to the center of NGC 5195, where the super-massive black hole is located.

“We think these arcs represent artifacts from two enormous gusts when the black hole expelled material outward into the galaxy,” said co-author Christine Jones, astrophysicist, and lecturer at the Harvard-Smithsonian Center for Astrophysics. “We think this activity has had a big effect on the galactic landscape.”

The researchers detected a willowy region of hydrogen gas emission just beyond the outer arc, suggesting that X-ray emitting gas expatriate the hydrogen gas from the center of the galaxy.

Furthermore, the properties of the gas around the arcs propose that the outer arc has flounced up enough material to trigger the formation of new stars. This type of phenomenon, where a black hole affects its host galaxy, is called feedback. Continue reading