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# Is there really 100 tredicillion Planck Time seconds each second?

## 31 posts in this topic

Regarding speed of transitions from on to off - we can (in very special circumstances) already work with spin flips and the hyperfine transition (which in simple terms is spin parallel to spin anti-parallel).

I just don't know the answer to this question - but how quickly can an electron flip? In a caesium atom it can do it just under 10 billion times a second - and I believe that in a rubidium atom it is significantly quicker. The energy levels involved are also miniscule (fractions of an electron volt).

Funnily enough the hyperfine transition straddles both branches of this thread; it was deemed basic enough and so unambiguously representable that it was included by Drake and Sagan on the Pioneer plaque. If I remember correctly it is the hyperfine transition time of hydrogen which the plaque uses to provide humanity's notions of both time and distance - the line for distance is 21 and a bit centimetres which is how long light travels for one cycle of transition

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Regarding speed of transitions from on to off - we can (in very special circumstances) already work with spin flips and the hyperfine transition (which in simple terms is spin parallel to spin anti-parallel).

I just don't know the answer to this question - but how quickly can an electron flip? In a caesium atom it can do it just under 10 billion times a second - and I believe that in a rubidium atom it is significantly quicker. The energy levels involved are also miniscule (fractions of an electron volt).

Funnily enough the hyperfine transition straddles both branches of this thread; it was deemed basic enough and so unambiguously representable that it was included by Drake and Sagan on the Pioneer plaque. If I remember correctly it is the hyperfine transition time of hydrogen which the plaque uses to provide humanity's notions of both time and distance - the line for distance is 21 and a bit centimetres which is how long light travels for one cycle of transition

The successor, I think, will be ones based on strontium.

In optical lattice clocks strontium atoms are trapped in the interference pattern of two laser beams. In this so called “optical lattice”, the atomic “pendulum”, i.e. the absorption frequency of the atoms, can then be determined very precisely – currently with an accuracy of 17 digits. http://www.ptb.de/cms/en/ptb/fachabteilungen/abt4/fb-43/ag-432/strontium-lattice-clock.html

This means that the time difference at a 1cm difference in elevation can be measured and won't gain or lose a second in 15 billion years!

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Let's do a thought experiment here:

If we speed-up an atom to 99-percent light-speed, it would at least travel a distance that could fit around Earth 2 times in 1 second, agree?

And can we agree that, when we "shoot" the atom out, at the Starting line, and when it reaches the Finish line (after 1 second), that it will have passed trillions of atoms? 400 million hydrogen atoms an fit in an inch, a ruler is like billions. Our atom went far, indeed.

And can we agree that atoms have been seen under microscopes where they aren't perfectly aligned with each-other like a atomic-grid? For example, if you make an L made of 3 atoms, and push the top atom over so it's a triangle, that is un-alignment, even over a crack.

--- This means our fired atom not only passes trillions of atoms, but also manyyyy many protons. So instead of saying it passes trillions (of atoms), we should say it passes like quintillions. That right there means there is quintillions of instances/moments/computational-ness each second for a computing transistor!

But there are things smaller than atoms and proteins, so what is the point of using them to measure the distance travelled?

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The successor, I think, will be ones based on strontium.

This means that the time difference at a 1cm difference in elevation can be measured and won't gain or lose a second in 15 billion years!

Rubidium Fountains can already exhibit mid 10^-17 of a second accuracy/stability for periods of a year - if I have read the paper correctly

https://arxiv.org/abs/1607.06776

These are functioning atomic clocks used for practical purposes

BTW - note the author

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BTW - note the author

For a dollar, I can put you in touch with this physicist. Actually touching him costs more.

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Rubidium Fountains can already exhibit mid 10^-17 of a second accuracy/stability for periods of a year - if I have read the paper correctly

https://arxiv.org/abs/1607.06776

These are functioning atomic clocks used for practical purposes

BTW - note the author

I think he said rubidium clocks are good for 20cm differences, which is still amazing in my book.

Edited by StringJunky
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