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<h1>Welcome to the<br>
<br>
Gravitation and Relativity Group,
<br>
including Scientific Computing,
<br><br>
at the University of Cologne</h1>
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<tr align=center><td><a href="research.html"><b>
Research
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<tr align=center><td><a href="groupMembers.html"><b>
Group members
</b></a></td></tr>
<tr align=center><td><a href="visitors.html"><b>
Visitors
</b></a></td></tr>
<tr align=center><td><a href="address.html"><b>
Address
</b></a></td></tr>
<tr align=center><td><a href="seminars.html" target="text"><b>
Seminars
</b></a></td></tr>
<tr align=center><td><a href="courses.html" target="text"><b>
Courses
</b></a>(in german)</td></tr>
<tr align=center><td><a href="events.html"><b>
Events
</b></a></td></tr>
<tr align=center><td><a href="links.html" target="text"><b>
Links
</b></a></td></tr>
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<a href=mailto:bs324@thp.uni-koeln.de><font
color=black>Contact</font></a></td></tr>
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<p align="justify">
Among the known interactions in Nature, gravitation is unique
in that it exerts a universal action on all kinds of matter
and energy. It dominates on large scales (cosmology) and for
compact objects (neutron stars, black holes), but is also important
for everyday physics. The gravitational interaction plays a
central role in the interplay between astrophysics, cosmology,
and particle physics.
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<p align="justify">
Modern gravitational theory started with Newton's universal attraction
law (1687): The gravitational force between two bodies is proportional
to mass 1 times mass 2 divided by their distance squared. As soon as
high velocities are involved between the masses, Newton's theory is
superseded by Einstein's gravitational theory (1915), also called
theory of general relativity. Therein, gravitation is a manifestation of the
geometry of four-dimensional spacetime.
For macroscopic phenomena, general relativity is an
experimentally well established theory.
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<p align="justify">
Our group investigates Einstein's theory and its possible extensions
in both the classical and quantum regime.
The methods involved
include quantisation of general relativity, an analysis of its
gauge structure, and quantum theory in curved backgrounds.
Particular applications are cosmology and the physics of black holes.
Because of
the complicated formalism, computer methodes such as numerics,
computer algebra, and visualisation are heavily used.
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