Bo Thidé

Bo Thidé
Bo Thidé
Born	8 January 1948 (age 76); Gothenburg, Sweden
Alma mater	Uppsala University
Known for	Quantum Mechanics, Electrodynamics, Plasma, Space physics
	Scientific career
Fields	Physicist
Institutions	Swedish Institute of Space Physics and Uppsala University
Doctoral advisor	Per Olof Fröman

Bo Yngve Thidé (born 8 January 1948) is a Swedish physicist and professor emeritus at Uppsala University. He has studied radio waves and other electromagnetic radiation in space, particularly their interaction with matter and fields.

Thidé was born in Gothenburg, Sweden.^{[citation needed]} He received his B.Sc. in 1972,^[1] his M.Sc. in 1973,^[2] and defended his Ph.D. thesis on semiclassical quantum theory at Uppsala University in 1979. His Ph.D. was obtained under the supervision of professor Per Olof Fröman at the Department of Theoretical Physics, Uppsala University. He has worked at the Swedish Institute of Space Physics in Uppsala^[3] since 1980, where he has been a professor since 2000.

In 1981, Bo Thidé discovered electromagnetic emissions stimulated by powerful radio waves in the ionosphere during experiments in August 1981 at the EISCAT facility in Tromsø, Norway.^[4] For the first time it was shown that the plasma turbulence excited by powerful radio waves in the ionosphere radiates secondary electromagnetic radiation that can be detected and analysed on the ground. These stimulated electromagnetic emissions (SEE) exhibit a rich spectral structure, particularly near harmonics of the ionospheric electron gyro frequency. The SEE technique is now a useful tool in plasma turbulence research. For his discovery, Thidé was awarded the Edlund Prize of the Royal Swedish Academy of Sciences in 1991.

In the mid-1980s, Thidé published a series of papers together with Bengt Lundborg on a highly accurate analytic approximation method to calculate the full three-dimensional wave pattern, spin angular momentum (polarization) and other properties of radio waves propagating in an inhomogeneous, magnetized, collisional plasma.

Thidé was involved in a project in The Netherlands where 12 500 antenna designed to analyse solar storms were built.^[5] In 2001 he led the LOIS-project, that placed tens of thousands of antenna in southern Sweden. The project was a subsidiary of the multinational LOFAR project headed by The Netherlands and aimed to find traces of the first hydrogen atom formed during Big Bang.^[6]

Together with colleagues from Italy and Spain, Thidé discovered in 2010 a new phenomenon in General Relativity which allows the detection of spinning black holes by analysing the orbital angular momentum and optical vortex structure of radiation from the accretion disk near the black holes. The results were published in Nature Physics.^[7] He was later part of a team which discovered that radio beams from fast-spinning black holes are twisted.^[8]

Thidé has advocated Orbital angular momentum multiplexing for radio transmissions, opening up additional degrees of freedom.^[9] Thidé is the author of the book Electromagnetic Field Theory, which is used in the course Classical Electrodynamics at Uppsala University and University of Padua. He has also worked on fiber optics technology.^[10]^[11]

Since 2016, he lives outside Söderhamn, where he continues his research from home.^[8]

References

^ "akademiska examina". Svenska Dagbladet (in Swedish). 8 May 1972. p. 2.
^ "Akademiska examina". Svenska Dagbladet (in Swedish). 16 July 1973. p. 12.
^ Städje, Jörgen (16 September 2010). "Tumlande radiovågor ändrar bilden av universum". TechWorld (in Swedish). No. 8/2010. pp. 70–72. Retrieved 27 July 2022.
^ B. Thidé; H. Kopka & P. Stubbe (1982). "Observations of Stimulated Scattering of a Strong High-Frequency Radio Wave in the Ionosphere". Physical Review Letters. 49 (21): 1561–1564. Bibcode:1982PhRvL..49.1561T. doi:10.1103/PhysRevLett.49.1561.
^ Westman, Henrik (16 October 2004). "Små klot håller koll på rymden". Dagens Industri (in Swedish). p. 9.
^ Peruzzi, Britt (21 October 2001). "Växsjö kan lösa universums gåta". Aftonbladet (in Swedish). p. 12.
^ F. Tamburini; B. Thidé; G. Molina-Terriza; G. Anzolin (2011). "Twisting light around rotating black holes". Nature Physics. 7 (3): 195–197. arXiv:1104.3099. Bibcode:2011NatPh...7..195T. doi:10.1038/NPHYS1907. S2CID 28065268.
^ ^a ^b Andersson, Felicia (21 May 2020). "Rymdforskare kastar nytt ljus över svarta hål". Borlänge Tidning (in Swedish). p. 5.
^ Fabrizio Tamburini, Elettra Mari, Anna Sponselli, Bo Thidé, Antonio Bianchini and Filippo Romanato (2012) "Encoding many channels on the same frequency through radio vorticity: first experimental test" New J. Phys. 14 033001 doi:10.1088/1367-2630/14/3/033001
^ Dahlberg, Markus (5 May 2015). "Rymdforskare tar fram ny bredbandsteknik". Sveriges Television (in Swedish). Retrieved 27 July 2022.
^ Tomassen, Emil. "Framtidens fiber forskas fram av Bo". Hudiksvalls Tidning (in Swedish). p. 7.