Problem: General relativity includes a dynamical spacetime, so it is difficult to see how to identify the conserved energy and momentum. Noether's theorem allows these quantities to be determined from a Lagrangian with translation invariance, but general covariance makes translation invariance into something of a gauge symmetry. The energy and momentum derived within general relativity by Noether's presecriptions do not make a real tensor for this reason. Einstein argued that this is true for fundamental reasons, because the gravitational field could be made to vanish by a choice of coordinates. He maintained that the non-covariant energy momentum pseudotensor was in fact the best description of the energy momentum distribution in a gravitational field. This approach has been echoed by Lev Landau and Evgeny Lifshitz, and others, and has become standard. The use of non-covariant objects like pseudotensors was heavily criticized in 1917 by Erwin Schrodinger and others.

Question: "Did Landau use dynamical spacetime in his theory, if not, what?"

Answer: "Non-covariant"
Answer: yes

Problem: (CNN) -- A Christian evangelical group said Thursday that a Bible school -- backed by American evangelist Franklin Graham -- was destroyed in the latest bombing raid to hit South Kordofan, an oil-rich Sudanese province that borders the newly created independent country of South Sudan. At least eight bombs were dropped in the area Wednesday during the school's first day of classes, according to a statement by Samaritan's Purse, Graham's Christian humanitarian group, which supports the school. Two bombs landed inside the compound -- located in the region's Nuba Mountains -- destroying two Heiban Bible College buildings and igniting grass fires across the area, the group said in a statement No injuries were reported. "It was a miracle that no one was injured," the statement added. Graham, who has called on the international community to take out Sudan's air assets and establish a no-fly zone in the region, said in a statement Thursday that he blamed Sudan's air force for the strike. At least four churches have been destroyed since August, the group said. "We are deeply concerned for the welfare and lives of the people of South Kordofan and we condemn the bombing of churches and Christian facilities," added Graham, son of the famed Rev. Billy Graham. More than 78,000 people have fled South Kordofan and Blue Nile states since August of last year after an armed rebellion took root, the United Nations reported. The Sudanese government is thought to have responded to the rebellion by conducting sustained air raids with the use of Russian-made Antonov bombers, which have raised concerns over civilian casualties. Decades of civil war between the north and south, costing as many as 2 million lives, formally ended with a U.S.-brokered peace treaty in 2005.

Question: "Where did the bombs drop?"

Answer: "South Kordofan"
Answer: yes

Problem: From Babylon, Alexander went to Susa, one of the Achaemenid capitals, and captured its legendary treasury. He sent the bulk of his army to the Persian ceremonial capital of Persepolis via the Royal Road. Alexander himself took selected troops on the direct route to the city. He had to storm the pass of the Persian Gates (in the modern Zagros Mountains) which had been blocked by a Persian army under Ariobarzanes and then hurried to Persepolis before its garrison could loot the treasury. On entering Persepolis, Alexander allowed his troops to loot the city for several days. Alexander stayed in Persepolis for five months. During his stay a fire broke out in the eastern palace of Xerxes and spread to the rest of the city. Possible causes include a drunken accident or deliberate revenge for the burning of the Acropolis of Athens during the Second Persian War.

Question: "Did Alexander storm the Persian Gates and enter Persepolis?"

Answer: "Yes"
Answer:
yes