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Arrows of Time

quantamagazine.org

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Re: Arrows of Time

#11

Post by sieste »

euroderf wrote: post #4
lisper wrote: post #3

> In an influential [2008] paper, Noah Linden, Sandu Popescu, Tony Short and Andreas Winter argued that the arrow of time can be explained in terms of quantum mechanical entanglement. As a physical system becomes entangled with its surroundings, it moves closer to equilibrium — and this one-way evolution determines time’s arrow. There is an alternative, much simpler way of looking at it that dates back to an overlook…

This is way off-topic, but... I remember reading once the idea that cats can remember the future. But I am unable to re-locate the source of this idea. Can anyone help ?

episode 53, when jerry dropped the anvil on tom's head.

Re: Arrows of Time

#14

Post by QuesnayJr »

dartos wrote: post #13
chriscjcj wrote: post #12

The title reminds me of the old joke... "Time flies like an arrow. Fruit flies like a banana."

Isn’t that a Zilean voice line from league of legends?

You're probably joking, but it dates to the 1960s (https://en.wikipedia.org/wiki/Time_flies_like_an_arrow;_frui...).

Re: Arrows of Time

#15

Post by MarkusQ »

euroderf wrote: post #4
lisper wrote: post #3

> In an influential [2008] paper, Noah Linden, Sandu Popescu, Tony Short and Andreas Winter argued that the arrow of time can be explained in terms of quantum mechanical entanglement. As a physical system becomes entangled with its surroundings, it moves closer to equilibrium — and this one-way evolution determines time’s arrow. There is an alternative, much simpler way of looking at it that dates back to an overlook…

This is way off-topic, but... I remember reading once the idea that cats can remember the future. But I am unable to re-locate the source of this idea. Can anyone help ?

> I remember reading once the idea that cats can remember the future.

Uh, that won't be discovered until 2057.

You aren't by any chance a cat, are you?

Re: Arrows of Time

#16

Post by intrasight »

lelag wrote: post #10
1010s1011 wrote: post #2

They completely forget one of the most famous historical historical clocks which preceded the Chinese mechanical clock (1090CE) they listed by about 280 years (807CE). It was gifted to Charlemagne, the Holy Roman Emperor, by Harūn al-Rashīd: https://muslimheritage.com/baghdad-clock/

I wish they would have said something about the Antikyrthera mechanism, an analog computer from the 2nd century BC capable of complex astronomical predictions and that was about one and half thousand years early compared to the next time we saw similar devices.

Since we saw - yes. Since they saw - we don't know.

But certainly the knowledge of such advanced analog computers was lost to humanity for centuries. Is humbling for sure.

Re: Arrows of Time

#17

Post by 082349872349872 »

mind-blight wrote: post #9
euroderf wrote: post #4

Earlier quoted context omitted.

This is way off-topic, but... I remember reading once the idea that cats can remember the future. But I am unable to re-locate the source of this idea. Can anyone help ?

You might be thinking about about done cats and dogs can tell an earthquake is coming a minute or two before it hits. That's not as much remembering the future as it likely is having a sense that we don't. But, it can feel like it

Instead of a sense we don't, it's probably just picking up on the P-waves instead of first noticing with the S-waves: https://earthquake.usgs.gov/earthquakes/events/1906calif/18a...

Re: Arrows of Time

#18

Post by daveguy »

I'm a little disappointed that an article about our understanding of time across history didn't include the marine chronometer. It was a major breakthrough for nautical navigation in the 1700s. It allowed precise longitude determination long before GPS. Prior to the marine chronometer latitude could be precisely determined with celestial navigation, but longitudinal skew due to earth's rotation could not be compensated for without precise timekeeping.

https://en.m.wikipedia.org/wiki/Marine_chronometer

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