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Monitoring nuclear weapons stockpiles with radio waves

An international research team has proposed a new method for monitoring nuclear disarmament treaties. The IT security experts developed a mechanism that uses radio waves to remotely monitor whether any changes are being made ...

Security

Q&A: Assessing the risks of existential terrorism and AI

Gary Ackerman, an associate professor and associate dean at the State University of New York's University at Albany College of Emergency Preparedness, Homeland Security and Cybersecurity (CEHC), has spent decades studying ...

Machine learning & AI

'Oppenheimer' a warning to world on AI, says director Nolan

The story of the invention of the atomic bomb told in the new film "Oppenheimer" is a "warning" to the world as we grapple with artificial intelligence, insists the movie's director Christopher Nolan.

Machine learning & AI

AI is an existential threat—just not the way you think

The rise of ChatGPT and similar artificial intelligence systems has been accompanied by a sharp increase in anxiety about AI. For the past few months, executives and AI safety researchers have been offering predictions, dubbed ...

Machine learning & AI

Scientists warn of AI dangers but don't agree on solutions

Computer scientists who helped build the foundations of today's artificial intelligence technology are warning of its dangers, but that doesn't mean they agree on what those dangers are or how to prevent them.

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Nuclear weapon

A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter; a modern thermonuclear weapon weighing little more than a thousand kilograms can produce an explosion comparable to the detonation of more than a billion kilograms of conventional high explosive. Even small nuclear devices can devastate a city. Nuclear weapons are considered weapons of mass destruction, and their use and control has been a major aspect of international policy since their debut.

In the history of warfare, only two nuclear weapons have been detonated offensively, both near the end of World War II. The first was detonated on the morning of 6 August 1945, when the United States dropped a uranium gun-type device code-named "Little Boy" on the Japanese city of Hiroshima. The second was detonated three days later when the United States dropped a plutonium implosion-type device code-named "Fat Man" on the city of Nagasaki, Japan. These bombings resulted in the immediate deaths of around 120,000 people (mostly civilians) from injuries sustained from the explosion and acute radiation sickness, and even more deaths from long-term effects of ionizing radiation. The use of these weapons was and remains controversial. (See atomic bombings of Hiroshima and Nagasaki for a full discussion.)

Since the Hiroshima and Nagasaki bombings, nuclear weapons have been detonated on over two thousand occasions for testing purposes and demonstration purposes. The only countries known to have detonated nuclear weapons—and that acknowledge possessing such weapons—are (chronologically) the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, the People's Republic of China, India, Pakistan, and North Korea. Israel is also widely believed to possess nuclear weapons, though it does not acknowledge having them. (For more information on these states' nuclear programs, as well as other states that formerly possessed nuclear weapons or are suspected of seeking nuclear weapons, see list of states with nuclear weapons.)

This text uses material from Wikipedia, licensed under CC BY-SA