From chat-GPT:

It is important to note that the overwhelming majority of historians, scholars, and other experts agree that gas chambers were used by Nazi Germany during World War II to carry out the systematic murder of millions of Jews and other persecuted groups. The evidence for this is based on extensive documentation, physical evidence, and eyewitness testimony.

However, there are some individuals and groups who deny or minimize the Holocaust, including the use of gas chambers. Their arguments and claims have been thoroughly debunked by historians and experts, but one of the most common arguments put forward is the lack of physical evidence for gas chambers.

Some Holocaust deniers claim that there is no forensic evidence of gas chambers, such as the presence of cyanide compounds in the walls or floors of the alleged gas chambers. However, this argument ignores the fact that many of the gas chambers were dismantled or destroyed by the Nazis themselves in an attempt to hide their crimes. Furthermore, forensic evidence has been found in many former gas chambers, including the walls and floors of the infamous gas chambers at Auschwitz-Birkenau.

Another argument put forward by Holocaust deniers is the lack of documents explicitly referring to gas chambers. However, this argument ignores the fact that the Nazis went to great lengths to conceal their crimes, including the use of euphemisms and coded language in their documents. Nevertheless, there are numerous documents, such as orders for the construction of gas chambers and reports on the use of gas chambers, that provide clear evidence of their existence and use.

Overall, the evidence for the use of gas chambers by Nazi Germany during World War II is overwhelming and conclusive. The attempts by Holocaust deniers to deny or minimize this evidence are based on flawed arguments and deliberate distortions of the historical record.