Abstract
This research highlights the significance of observing and studying the deflections and redshifts of electromagnetic waves caused by gravitational waves. Gravitational waves are ripples in space-time that are generated by accelerating large celestial masses. Gravitational waves carry information about the source that they are generated from, but they can take a long time to reach and it is hard to detect them due to the waves getting weaker as they travel. By using multi-messengers (light, cosmic rays, etc.), tracking and measuring the gravitational waves can be easier. A study done by Thibault Damour showed that the deflection angle and the redshift on light caused by gravitational waves are minimal. However, advancements such as the Very Long Baseline Interferometer(VLBI) can help detect these redshifts and deflections. This study aims to highlight the advancements that can help detect those deflections and, therefore, leverage our understanding of the gravitational waves and their sources. More revelations and discoveries can be made by analyzing the interaction between gravitational waves and electromagnetic waves.
Introduction
Gravitational waves are distortions in the space-time fabric that are caused by the acceleration of the celestial bodies and large masses. These ripples on space-time fabric cause curvatures that look like ripples on a pond. The ripples propagate away from the source at the speed of light, carrying information about the source to the space. The detection of these gravitational waves revolutionized our understanding of the universe and helped us to get better insight into cosmic events. It has also improved our understanding of the existing theories and concepts such as general relativity, a theory by Einstein. Gravitational waves are not like electromagnetic or mechanical waves, they do not need a medium to propagate like mechanical waves, and they do not consist of photons like electromagnetic waves. Another type of wave that can propagate in space like gravitational waves is electromagnetic waves.
Both gravitational waves and electromagnetic waves do not need a medium to propagate, unlike mechanical waves. Electromagnetic waves consist of photons, and they vary in wavelengths that correspond to different light intensities. Because electromagnetic waves do not need a medium, the photons can travel from the stars to our planet through space where there isn’t a medium. Gravitational waves can interfere with the electromagnetic waves, causing deflections. Depending on how close the waves are or how powerful the gravitational waves are, the deflections can be different. This relationship can be observed further to reveal more information about the source. Gravitational waves depend on how big the mass of the celestial body is, and depending on that the electromagnetic waves curve towards the source. Measuring and observing the deflection of the electromagnetic waves caused by gravitational waves can lead to revelations and discoveries, as well as be used for several purposes such as mass measurements of the source body.
Literature review
Research done by Thibault Damour on “light deflection by gravitational waves from localized sources” highlights that the deflections caused by the gravitational waves are too minimal to be detected. In his study, Damour mentioned how perturbations are caused by gravitational waves, and how the deflections are minimal to the point where it is almost negligible. Damour had used the perturbation theory to express the spacetime as a flat sheet, and the gravitational waves as the small ripples that caused perturbations. Damour had proposed several equations that involved calculations of the deflection angle, geodesic equations, and the impact parameter to further provide explanations for his findings. The deflections caused by the gravitational waves cause the light to change in wavelength, therefore experiencing a redshift. Although this redshift can be used to gain further information about the magnitude of the gravitational waves, the redshift is too minimal and it
is overshadowed by cosmic expansion or other massive objects that produce larger redshifts, according to Damour. This study highlights the fact that the deflection is minimal and hard to observe, which is important for this research when it comes to studying the possibility of observing the redshift and the deflection angle. Damour’s study provides an in-depth explanation of the minimality of the redshifts and the deflections, highlighting the need for advanced technology. Taking into consideration that the study took place in 1998, a new technology to observe the redshift and the deflection angle can help our understanding of the perturbation of gravitational waves and potentially help us gain information about the sources of the waves. This research aims to bring out advancements that can help us further detect those minimal shifts, studying the gravitational wave sources more effectively and efficiently.
The first gravitational wave that was detected with an aftermath of electromagnetic waves was GW170817. It belonged to a binary pair of neutron stars from the galaxy NGC 4993 that collided together. It was observed on 17 August 2017, by LIGO and Virgo detectors. It was a wave that lasted 100 seconds, starting with a frequency of 24 Hz, and had approximately 3000 cycles. The importance of the detection of GW170817 is that this wave was a significant start for multi-messenger astronomy. Multi-messenger astronomy is the subfield of astronomy where multiple messengers from the same source are observed and interpreted to get further information about cosmic events. Events such as binary neutron stars, binary black holes, gamma-ray bursts, or supernovas can create multiple messengers. Messengers are of four types; electromagnetic waves(photons), gravitational waves, cosmic rays, and neutrinos. These messengers can be detected by different detectors and sources. The main benefit of multi-messenger astronomy is the detailed and accurate information gathered by combining different messengers. Another benefit is the time difference and the time saved. Some waves can take years to reach and get noticed by the detectors, so interpreting multiple waves at once can save a lot of time for astronomers.
Methodology
Even though the light that is deflected by the gravitational waves would have a slight red shift and there would be a tiny deflection angle, with the right detectors and advancements the light waves can be detected. This increases the possibility of detecting a gravitational wave and improving the information received from the source. VLBI technique can be used to detect these redshifts.VLBI(Very Long Baseline Interferometry) is a technique where multiple radio telescopes are used to get more accurate and high-angular resolution waves. This approach will allow for precise and detailed measurements. Since there are a lot of stars and events happening that produce light, overshadowing the redshifts caused by the gravitational waves would be a challenge for radio telescopes. VLBI can help detect minimal deflections and shifts in wavelength. Calculating the redshift caused by the gravitational waves and comparing the results gathered by the VLBI, the deflection can be tracked and the source of the gravitational wave can be found. By finding the source, more information can be gathered about the event, potentially leading to discoveries and revelations.
Conclusion
In this research, the interaction between electromagnetic waves and gravitational waves was investigated. Through the study of Thibault Damour, the minimality of the perturbations was highlighted, discussing the challenges and the complexities of investigating the multi-messenger interaction. By proposing the use of advancements such as VLBI, observing and identifying these deflections and redshifts can become more precise and efficient. This will lead to a more accurate identification of the gravitational waves, and more information about these sources can be gathered. These findings highlight the importance of the advancements in enhancing and improving our knowledge and abilities in the field of such cosmic events. In future research, improving and advancing the detection systems should be
focused on for discoveries that can get new insights into the nature of gravitational waves and how they interact with other cosmic phenomena through new advancements.
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