In 1900, Einstein's paper "Folgerungen aus den Capillaritätserscheinungen" ("Conclusions from the Capillarity Phenomena") was published in the journal Annalen der Physik. On 30 April 1905, Einstein completed his thesis, with Alfred Kleiner, Professor of Experimental Physics, serving as pro-forma advisor. As a result, Einstein was awarded a PhD by the University of Zürich, with his dissertation A New Determination of Molecular Dimensions.
In April 1908, another uprising was launched in Yunnan, Hekou, called the Hekou Uprising. Huang Mingtang led two hundred men from Vietnam and attacked Hekou on 30 April. Other revolutionaries who participated include Wang Heshun and Guan Renfu. They were outnumbered and defeated by government troops, however, and the uprising failed.
On 30 April, French Foreign Minister Stéphen Pichon summoned Ion I.C. Brătianu, the Romanian representative to the Paris Peace Conference. Romania was told to cease its advance at the Tisza River and retreat to the first demarcation line imposed by the Allied council. Brătianu promised that Romanian troops would not cross the Tisza River.
As Soviet forces continued to fight their way into the centre of Berlin, Hitler and Braun committed suicide on the afternoon of 30 April. Braun took cyanide and Hitler shot himself. Pursuant to Hitler's instructions, their bodies were carried up to the Reich Chancellery garden and burned.
In accordance with Hitler's last wishes, Bormann was named as Party Minister, thus officially confirming his top position in the Party. Grand Admiral Karl Dönitz was appointed as the new Reichspräsident (President of Germany) and Goebbels became head of government and Chancellor of Germany. Goebbels and his wife Magda committed suicide later that day.
Yaeko Sakano, more often referred to as Yaeko Ueno, was an unmarried partner to Hidesaburō Ueno for about 10 years until his death in 1925. Hachikō was reported to have shown great happiness and affection towards her whenever she came to visit him. Yaeko died on 30 April 1961 at the age of 76 and was buried at a temple in Taitō, further away from Ueno's grave, despite her requests to her family members to be buried with her late partner.
He soon instituted phased U.S. troop withdrawals (From Vietnam), but also authorized incursions into Laos, in part to interrupt the Ho Chi Minh trail, which passed through Laos and Cambodia and was used to supply North Vietnamese forces. Nixon announced the ground invasion of Cambodia to the American public on April 30, 1970.
On 30 April 1975, NVA troops entered the city of Saigon and quickly overcame all resistance, capturing key buildings and installations. A tank from the 324th Division crashed through the gates of the Independence Palace at 11:30 am local time and the Viet Cong flag was raised above it. President Dương Văn Minh, who had succeeded Huong two days earlier, surrendered to Colonel Bùi Tín.
In the early morning hours of 30 April, the last U.S. Marines evacuated the embassy by helicopter, as civilians swamped the perimeter and poured into the grounds. Many of them had been employed by the Americans and were left to their fate.
Pressure from the U.S. government and critical sectors of Colombian society was met with further violence, as the Medellín Cartel and its hitmen, bribed or murdered numerous public officials, politicians and others who stood in its way by supporting the implementation of extradition of Colombian nationals to the U.S. Victims of cartel violence included Justice Minister Rodrigo Lara Bonilla, assassinated in 1984, an event which made the Betancur administration begin to directly oppose the drug lords.
The government's tone grew increasingly conciliatory as Zhao Ziyang returned from Pyongyang on 30 April and resumed his executive authority. In Zhao's view, the hardliner approach was not working, and concession was the only alternative. Zhao asked that the press be opened to report the movement positively, and delivered two sympathetic speeches on 3–4 May.
On 1 May 2007, Nintendo acquired an 80% stake in video game development company Monolith Soft, previously owned by Bandai Namco. Monolith Soft is best known for developing role-playing games such as the Xenosaga, Baten Kaitos, and Xenoblade series.
On April 30, 2009, the U.S. State Department reported that al-Zawahiri had emerged as al-Qaeda's operational and strategic commander and that Osama bin Laden was now only the ideological figurehead of the organization. However, after the 2011 death of bin Laden, a senior U.S. intelligence official was quoted as saying intelligence gathered in the raid showed that bin Laden remained deeply involved in planning: "This compound (where bin Laden was killed) in Abbottabad was an active command-and-control center for al-Qaeda's leader. He was active in operational planning and in driving tactical decisions within al-Qaeda."
On 29 April 2011, Middleton and Prince William got married in Westminster Abbey, with the day declared a bank holiday in the United Kingdom. Estimates of the global audience for the wedding ranged around 300 million or more, whilst 26 million watched the event live in Britain. On marriage, Catherine assumed the style "Her Royal Highness The Duchess of Cambridge".