For the first time scientists have experimentally demonstrated that sound waves can exceed the speed of light.
Not only sound but some previous experiments have also demonstrated that the group velocities of other material components such as optical, microwave and electric pulses can also exceed the speed of light.
The experiment was conducted by two undergraduate students, a high school teacher and two high school students. The students were able to achieve speed more than that of light by rephrasing the spectral components of sound pulses. So we can say that it is not the actual sound waves but the group velocity of the waves that can exceed the speed of light.
To change the phase of the sound the waves were sent through an asymmetric loop filter on a waveguide of PVC pipe that was about 8m long. The waves then undergo anomalous dispersion and the sound pulses that are traveling through the loop filter arrived at the exit earlier than the pulses that were traveling through the PVC pipe.
Although the results may look like they are violating the theory of Relativity that was proposed by Einstein. The theory stated that no material object can exceed the speed of light but we have to consider the fact that the waves are not material as the researchers are passing them through a filter.
Though the research will not be able to develop space ships that can reduce the Earth and Mars transit time yet they are a significant breakthrough in the fields of science.
Via: physorg
