Posted: March 24th, 2023

What are Gravitational Waves?

Introduction

Einstein postulated the first existence of gravitational waves in 1916 as an outcome of his theory based on the General Relativity. Although there has not been direct detection of such waves, it is worth noting that the work of Russell Hulse and Joseph Taylor made a significant evidence when they observed two orbiting neutron stars around each other in the same aspect that would be expected if the same star with binary neutron would behave when emitting energy in the form of gravitational waves.[1]

Gravitational Waves

These fluctuate the movement of massive bodies generates gravitational fields. In fact, they create ripples in the space-time, making distortions that create a movement of the speed of light in the space-time travel. Therefore, the bodies that are on that path of the waves experience a gravitational tidal force, which is directed perpendicularly from the propagation direction of the wave (Kokktas 67). In the same aspect, these forces alter the distance between the points proportional to the size of the change.

Gravitational waves can be sensed by those devices that quantify the induced length changes. In this aspect, the amplitudes and frequencies of the waves are linked to the motion of the involved masses (Crocket 1). Therefore, the analysis and measure of the gravitational waves enhance our understanding of their source if the detectors involved in their observation are more than two during the estimation of position and distance of their source.

Theory of Gravitational Waves

The theory of gravity by Newton enjoyed great success in various aspects, including motions of celestial bodies as well as our everyday life. The theory is recognized as one of the most ingenious human mind creations. The general relativity laws differ from Newton’s theory because it introduces the aspect of the geometry of the space-time (Hughes 108). As an apple falls from the top of the tree, the theory has rearranged the distribution of earth mass, the changes of gravitational fields, the ability of observation of these changes using high-precision instrument by a distant observer.

In fact, the changes of the gravitational waves, according to Newton, are instantaneous, indicating that they use infinite speed. If this supposition by Newton were true, then the principle of causality would not stand. Therefore, no media can travel faster than the speed of light. In this aspect, the theory of Einstein avoids such ambiguity by indicating that gravitational waves spread at a finite speed, which is the speed of light and the ripple under the space-time fabric (Grant 6). In essence, the presence of gravitational waves is an instantaneous consequence of the relativity gravity theory. However, the form and strength depend on the gravitational theory details.

Importance of Gravitational Waves

Detecting these waves will open a new window for observational astronomy because the information transmitted by gravitational waves varies from that transmitted by electromagnetic waves. In fact, the new frontier of gravitational waves will accomplish the view of the cosmos and will unveil the concept of space-time surrounding black holes. In addition, it will assist the direct observation of the binary system, the merging and creation of neutron stars or black holes, and unveil the origin of the early moments of the universe, as well as observe the center of galaxies where black holes with supermassive solar masses are hidden (Grant 7).

As is evident from the above analysis, the knowledge of gravitational waves is a field of interest in the current world because it will enable the fundamental prediction of the general relativity concept that lacks direct confirmation, enhance the probing of the history of the universe, and offer the required technology, which may be capable of detecting the gravitational waves.   

Works Cited

Crocket, Christopher. “Gravitational wave discovery gives way to dust.” Science News 2014: 7. JSTOR Journals. Web. 3 Apr. 2016.

Grant, Andrew. “Physicists detect gravitational waves: LIGO experiment’s discovery opens a new window to the cosmos.” Science News 2016: 6. Academic OneFile. Web. 3 Apr. 2016.

Hughes, Scott A. “Gravitational Waves from Merging Compact Binaries.” Annual Review of Astronomy and Astrophysics 47.1 (2009): 107-157.

Kokktas, Kostas, D. Gravitational Wave Physics. Encyclopedia of Physical Science and Technology, Eighteen-Volume Set. 67-85, Jan. 1, 2003. ISSN: 978-0-12-227410-7. Print.

Weinstein, Galina. “Einstein’s Discovery of Gravitational Waves 1916-1918.” (2016): arXiv. Web. 3 Apr. 2016.

Galina Weinstein, “Einstein’s Discovery of Gravitational Waves 1916-1918.” (2016): arXiv. Web. 3 Apr. 2016.