| Texto completo | |
| Autor(es): |
Torres, Theo
;
Patrick, Sam
;
Coutant, Antonin
;
Richartz, Mauricio
;
Tedford, Edmund W.
;
Weinfurtner, Silke
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Nature Physics; v. 13, n. 9, p. 833+, SEP 2017. |
| Citações Web of Science: | 46 |
| Resumo | |
When an incident wave scatters off of an obstacle, it is partially reflected and partially transmitted. In theory, if the obstacle is rotating, waves can be amplified in the process, extracting energy from the scatterer. Here we describe in detail the first laboratory detection of this phenomenon, known as superradiance(1-4). We observed that waves propagating on the surface of water can be amplified after being scattered by a draining vortex. The maximum amplification measured was 14% +/- 8%, obtained for 3.70 Hz waves, in a 6.25-cm-deep fluid, consistent with the superradiant scattering caused by rapid rotation. We expect our experimental findings to be relevant to black-hole physics, since shallow water waves scattering on a draining fluid constitute an analogue of a black hole(5-10), as well as to hydrodynamics, due to the close relation to over-reflection instabilities(11-13). (AU) | |
| Processo FAPESP: | 15/14077-0 - Superradiância em sistemas dissipativos |
| Beneficiário: | Maurício Richartz |
| Modalidade de apoio: | Bolsas no Exterior - Pesquisa |
| Processo FAPESP: | 13/15748-0 - Modelos análogos: superradiância e estabilidade |
| Beneficiário: | Maurício Richartz |
| Modalidade de apoio: | Bolsas no Exterior - Pesquisa |
| Processo FAPESP: | 10/20123-1 - Modelos análogos de gravitação |
| Beneficiário: | Maurício Richartz |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 05/04219-0 - Limites da gravitação semi clássica: o regime transplanckiano |
| Beneficiário: | Maurício Richartz |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado Direto |
| Processo FAPESP: | 13/09357-9 - Física e geometria do espaço-tempo |
| Beneficiário: | Alberto Vazquez Saa |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |