General relativity is a theory of gravitation that was developed by
Albert Einstein. According to general relativity, the observed
gravitational attraction between masses results from the warping of
space and time by those masses. Before the advent of general
relativity, Newton's law of universal gravitation had been accepted.
Experiments show that Einstein's description accounts for several
effects that are unexplained by Newton's law. Some general relativity
predictions have been confirmed by experiment, while others are the
subject of ongoing research. General relativity has developed into an
essential tool in modern astrophysics. It provides the foundation for
the current understanding of black holes and of the standard Big Bang
model of cosmology. Although general relativity is not the only
relativistic theory of gravity, it is the simplest such theory that is
consistent with the experimental data. Nevertheless, a number of open
questions remain: the most fundamental is how general relativity can be
reconciled with the laws of quantum physics to produce a complete and
self-consistent theory of quantum gravity.
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Today's selected anniversaries:
Bolesław I Chrobry became the first King of Poland.
Construction of the current St. Peter's Basilica in Vatican City, to
replace the old St. Peter's Basilica built in the 4th century, began.
A major earthquake and resulting fires devastated San Francisco,
killing at least 3,000 people and leaving more than half of the city's
World War II: Sixteen B-25 Mitchell bombers from the aircraft carrier
USS Hornet carried out the Doolittle Raid, the first Allied attack on
the Japanese home islands.
A suicide bomber destroyed the United States Embassy in Beirut with a
car bomb, killing over 60 people.
Israeli forces shelled Qana, Lebanon, during Operation Grapes of Wrath,
killing over 100 civilians and injuring over 110 others at a UN
Wiktionary's word of the day:
1. To heal a wound through scarring (by causing a scar or cicatrix to
2. To form a scar
Wikiquote quote of the day:
I believe that music can be an inspirational force in all our lives —
that its eloquence and the depth of its meaning are all-important, and
that all personal considerations concerning musicians and the public
are relatively unimportant — that music come from the heart and returns
to the heart — that music is spontaneous, impulsive expression — that
its range is without limit — that music is forever growing — that music
can be one element to help us build a new conception of life in which
the madness and cruelty of wars will be replaced by a simple
understanding of the brotherhood of man.
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