:: OSEL.CZ :: – 247 asksseconds: The shortest measured time period in history

German physicists took a hydrogen molecule and fired an X-ray photon from a PETRA III laser source in DESY. From the observed interference between the photon and the electrons of this molecule, they ingeniously derived the time it takes for a photon to fly from one atom to another. It is a world record in measuring the shortest time.

How to measure in questionsseconds? Credit: Sven Grundmann / Goethe University Frankfurt.

Egyptian chemist Ahmed Zewail received the 1999 Nobel Prize for measuring the rate of change of shape of molecules. He founded a completely new field of femtochemistry, which works with ultrashort laser beams. With their help, it is possible to measure the femtosecond times required to form or break a chemical bond.

The year is now 2020, and a team of physicists led by Reinhard Dörner from Johann Wolfgang Goethe-Universität Frankfurt in Germany has gone much deeper into femtoseconds. In their groundbreaking study, they measured the time it takes for a photon to fly the distance corresponding to a hydrogen molecule. It takes up to 247 questions per second, ie 247 trillionths (10-21) seconds. This is the shortest time we have ever measured reliably.

Reinhard Dörner.  Credit: / Goethe University Frankfurt.

Reinhard Dörner. Credit: / Goethe University Frankfurt.

What did such an experiment look like? They used hydrogen molecules H for this2, which were irradiated with X – rays from the PETRA III X – ray laser source at the German research facility DESY in Hamburg. At the same time, they adjusted the energy of the X-rays so that one X-ray photon “kicked out” both electrons from the molecule with hydrogen, which the molecule normally contains.

Goethe University Frankfurt, logo.

Goethe University Frankfurt, logo.

Electrons behave like particles as well as waves. And in this case, the photon acts like a plaid thrown to the surface. The result is specific interference that can be analyzed. Dörner’s team used a special device (COLTRIMS reaction microscope) that can visualize ultrafast processes in atoms and molecules. COLTRIMS also determines how oriented the hydrogen molecule is.

When researchers knew the orientation of the hydrogen molecule under study, they could deduce from the X-ray photon interference pattern exactly when the photon “kicked” the first electron of the molecule and when the second electron. As a result, it takes up to 247 seconds, depending on the orientation of the molecule relative to the incoming photon. Dörner adds that they were the first to observe how the electron envelope did not react to the whole light beam in a single moment. The slight time lag is due to the fact that information cannot propagate through a molecule faster than the speed of light.

Video: Reinhard Dörner – 2019 Schawlow-Townes Symposium



Goethe University Frankfurt October 16, 2020.

Science 370: 339 –341.


This is how it will be to play old games on the new Xbox consoles

Microsoft tempts with better graphics and higher refresh rates on selected titles.

About a month before the Xbox Series X and S launches, Microsoft will release new details on how older Xbox games will run on the new consoles.

Series X and S will support thousands of games from older generations, and Microsoft claims that the games will run better on the new consoles, thanks to stronger machine power and some other ingenious technical solutions.

According to the company, this will lead to, among other things, better graphics performance and shorter loading times.

Auto HDR

Microsoft announced yesterday that the new consoles come with an Auto HDR mode that is enabled by default for backward compatible games.

Below you can see how Auto HDR gives more vibrant colors:

«Auto HDR is implemented in the system so that developers do not have to do any work to take advantage of this feature », explains Peggy Lo, Head of Xbox Compatibility Program.

In addition to the Auto HDR function, players will experience that selected older games run at 60 frames per second, instead of 30.

Fallout 4 with 60 frames per second

An example of this can be seen in the video below, where Fallout 4 runs at a refresh rate of 60 frames per second on the Xbox Series S. In today’s Xbox One X version, the same game is locked at 30 frames per second.

Higher resolution

Microsoft also confirms that the “Heutchy” method, which made it possible to upgrade selected Xbox and Xbox 360 titles to 4K resolution on Xbox One X, will also be used on the new consoles. This means that more games will be able to run in 1440p on Xbox Series S and in 4K on Xbox Series X.

«Taking care of our games from the past is fundamental to our DNA in the Xbox, and a promise we give you. Backward compatibility allows you to relive your finest game memories in new ways. Your favorite games keep everything the original developers wanted, but at the same time you get to experience improvements and exciting new features », Microsoft writes in the blog post.

If you want to read more about Xbox ‘backward compatibility, we recommend that you read this blog post from Microsoft.



UN: Venezuela, Maduro attacks the US, Guaidó asks for ‘actions’ – Ultima Ora

(ANSA) – CARACAS, SEPTEMBER 24 – Venezuelan President Nicolás Maduro and opposition leader Juan Guaidó virtually intervened on behalf of Venezuela in the 75th general session of the UN: the first to attack United States policy and the second to ask the international community to consider “appropriate actions” to restore freedom to Venezuelans.

In his speech Maduro accused the US of being “a threat to global peace” with its violations of the principles of international law and the United Nations Charter.

“We want to tell the supremacist government in Washington – he later said – that the world is watching it, and that it can still return to the rules of international law, overturning the discredit and malaise that its arbitrariness and arrogance cause”.

By continuing to follow the path of violating the UN charter, he continued, for the US there will be isolation, discredit and condemnation by the peoples “.

For his part, Guaidó, self-proclaimed interim president of Venezuela, reminded UN Secretary-General Antonio Guterres of his 2018 statement, according to which “the fundamental principles mean little if they are not applied when necessary”.

The opposing leader then underlined that with the help of international allies, mechanisms of “preventive diplomacy” have been used in recent years, but that “we have almost reached the end of the options available to solve the problem using peaceful and diplomatic mechanisms”.

Therefore, “today I ask the representatives of the member states to take responsibility for assisting the legitimate government of Venezuela in its mission to protect the Venezuelan people, and to consider a strategy that contemplates other options after the diplomatic path is exhausted. the moment – he concluded – for opportune and decisive actions “. (ANSA).